neutral third party - ohio department of transportation · december 31, 2003. upon issuing its...

Neutral Third Party Ohio Pavement Selection Process Analysis

Final Report

Prepared for Ohio Department of Transportation

Pavement Selection Advisory Council 1980 W. Broad Street

Columbus, Ohio 43223

Prepared by ERES Consultants Division of Applied Research Associates, Inc.

505 W. University Avenue Champaign, Illinois 61820

December 12, 2003

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FOREWORD During the 2003–2004 regular session of the General Assembly, the Ohio State Legislature included in Section 12 of House Bill 87 the following provision calling for an evaluation of the Ohio Department of Transportation’s (ODOT’s) pavement type selection process:

The Ohio Department of Transportation shall contract with a neutral third-party entity to conduct an analysis of the Department's pavement-selection process including but not limited to life cycle cost analysis; user delay; constructability and environment factors. The entity shall be an individual or an academic, research, or professional association with an expertise in pavement-selection decisions and shall not be a research center for concrete or asphalt pavement. The analysis shall compare and contrast the Department's pavement-selection process with those of other states and with model selection processes as described by the American Association of State Highway and Transportation Officials and the Federal Highway Administration. An advisory council shall be appointed to approve the scope of study and to select the neutral third-party entity. The advisory council shall consist of the following members:

(1) The director of the Ohio Department of Transportation, who shall act as Chairman of the council;

(2) A member of the Ohio Society of Certified Public Accountants; (3) A member of a statewide business organization representing major

corporate entities from a list of three names submitted to and appointed by the Speaker of the House of Representatives;

(4) A member of the Ohio Society of Professional Engineers; (5) A member of a business organization representing small or independent

businesses from a list of three names submitted to and appointed by the President of the Senate;

(6) A representative of the Ohio Concrete Construction Association; (7) A representative of Flexible Pavements Association of Ohio, Inc.

Members of the advisory council representing the Ohio Society of Certified Public Accountants, the Ohio Society of Professional Engineers, the small or independent businesses and the major corporate entities shall have no conflict of interest with the position. For purposes of this section, "conflict of interest" means taking any action that violates any provision of Chapter 102. or 2921. of the Revised Code. The advisory council shall be appointed no later than July 31, 2003. Once appointed, the council shall meet, at a minimum, every thirty days. The council shall publish a schedule of meetings and provide adequate public notice of these meetings. The meetings are also subject to the applicable public meeting requirements. The council shall allow a comment period of not less than thirty

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days before issuing its final report. The report shall be issued on or before December 31, 2003. Upon issuing its final report, the council shall cease to exist. The Department shall make changes to its pavement-selection process based on the recommendations included in the third-party entity's report.

This report presents the findings and recommendations reached by the neutral third party (NTP), the ERES Consultants Division of Applied Research Associates, Inc. The NTP interviewed and took testimony from representatives of the Flexible Pavements of Ohio, Ohio Concrete Construction Association, and ODOT. In addition, the NTP team traveled to 10 States/Provinces where they interviewed respective DOT staff members regarding the processes they follow in making pavement type selections. Informal discussions were also held with representatives of the asphalt and concrete pavement associations in those 10 States/Provinces, as well representatives of the Federal Highway Administration (FHWA) in the Ohio Division and Washington Headquarters offices. This report was prepared by key staff members of the NTP. These individuals include Mr. John P. Hallin (Project Manager), Mr. David K. Hein (Assistant Project Manager), Mr. Harold L. Von Quintus, Dr. Michael I. Darter, Mr. Kelly L. Smith, and Mr. Jag Mallela.

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TABLE OF CONTENTS INTRODUCTION ...........................................................................................................................1 BACKGROUND .............................................................................................................................3 ISSUES ............................................................................................................................................4 Flexible Pavement Industry Issues...................................................................................................4 Rigid Pavement Industry Issues.......................................................................................................5 Issues Raised by the General Public ................................................................................................7 PRACTICES OF COMPARISON STATES/PROVINCES............................................................8 Background......................................................................................................................................8 Agency Type Selection Processes .................................................................................................10 Detailed Findings of State Practices ..............................................................................................15 FHWA AND AASHTO GUIDANCE...........................................................................................25 FHWA Policy and Guidance .........................................................................................................25 AASHTO Guidance .......................................................................................................................27 CONCLUSIONS AND RECOMMENDATIONS ........................................................................29 Conclusions....................................................................................................................................29 Recommendations..........................................................................................................................30 REFERENCES ..............................................................................................................................40 APPENDIX A: “PAVEMENT SELECTION THE ODOT WAY” APPENDIX B: PAVEMENT TYPE SELECTION FLOW CHARTS FOR 10 COMPARISON STATES APPENDIX C: COMPLETED CURRENT QUESTIONNAIRES FOR THE COMPARISON

STATES APPENDIX D: COMPARISON OF STATE PAVEMENT PRACTICES APPENDIX E: CONCEPTS FOR DEVELOPMENT OF SURVIVAL CURVES AND

PROCEDURES FOR ADJUSTMENT OF SURVIVAL CURVES TO ACCOUNT FOR NEW TECHNOLOGY

APPENDIX F: MEETING FACILITATOR SCOPE OF WORK APPENDIX G: EVALUATION OF THE FUTURE MAINTENANCE SCHEDULE

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INTRODUCTION Pavement type selection is one of the more challenging engineering decisions that highway administrators face today. They must balance issues of both short- and long-term performance with initial and long-term costs. The stakeholders that highway administrators answer to, the traveling public, generally do not express strong feelings on the type of pavement constructed, as long as reasonable levels of service, safety, and ride quality are provided. However, administrators must deal with the spirited competition that exists between the asphalt and concrete pavement industries. Competition can be healthy when it leads to improvements in overall quality and cost reductions. It becomes unhealthy when it results in engineering decisions being moved to the political arena. It is an agency’s responsibility to provide its constituents (the traveling public) with cost effective, good-performing roads. Conversely, it is the responsibility of the industries to illustrate that their products meet or exceed established performance criteria and are cost effective. It is prudent for both parties to use innovation and new technologies to improve the overall performance and long term cost effectiveness of Ohio’s roads. The dilemma facing the highway engineer or administrator can be summarized best by the following quote from the American Association of State Highway and Transportation Officials (AASHTO) Guide for Design of Pavement Structures [1]:

The selection of pavement type is not an exact science but one in which the highway engineer or administrator must make a judgment on many varying factors such as traffic, soils, weather, construction, maintenance, and environment. The selection process may be facilitated by comparison of alternative structural designs for one or more pavement types using theoretical or empirically derived methods. However, such methods are not so precise as to guarantee a certain level of performance from any one alternate or comparable service for all alternatives. Also, comparative cost estimates can be applied to alternate pavement designs to aid in the decision-making process. The cost for the service of the pavement should include not only the initial cost but also subsequent cost to maintain the service level desired. It should be recognized that such procedures are not precise since reliable data for maintenance, subsequent stages of construction, or corrective work and salvage value are not always available, and it is usually necessary to project costs to some future point in time. Also, economic analyses are generally altruistic in that they do not consider the present or future capabilities of the contracting agency.

To further cloud the issue of pavement type selection, highway administrators face a high degree of uncertainty regarding the types of loadings a pavement will experience during a pavement life that can range from 20 to 50 years. During the nearly 50 years since the beginning of the

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Interstate program, the United States has experienced a number of unforeseen changes in traffic and traffic loadings. These have included legislative changes that increased the size and weight of trucks, a large move from rail freight movement to truck freight, and just-in-time delivery. Because of this uncertainty, pavement type selection processes are largely subjective and tailored to the needs of each individual State highway agency. The neutral third party (NTP) was tasked by the Ohio Pavement Selection Advisory Council (PSAC) with minimizing the subjectivity of Ohio’s pavement selection process by reviewing the existing process and making recommendations for improvement. We began this assignment with a number of beliefs, and those beliefs were not altered during our review of what other States are doing:

• Pavement type selection is an engineering decision that is the sole responsibility of the highway agency.

• In most cases where pavement type selections are made on high-volume routes (Interstates, freeways, toll roads), properly designed and constructed flexible or rigid pavements will provide an excellent level of service.

The recommendations provided in this document are based largely on practices of the States/Provinces selected for review, along with guidance provided by AASHTO and the Federal Highway Administration (FHWA). When reviewing the practices of other States, we tried to identify advantages and disadvantages with specific aspects of their systems. We also consulted the trade organizations in a number of the States to get their views on pavement type selection. This report is structured to present a summary of the issues that were raised by the pavement industries in Ohio, a review of the pavement design and selection processes of 10 highway agencies, a review of AASHTO and FHWA guidance on pavement type selection, and conclusions and recommendations to address the issues raised for the pavement type selection process in Ohio. Detailed information collected during the study is presented in the appendices.

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BACKGROUND The Ohio Department of Transportation (ODOT), as part of its responsibility to make economically sound decisions that provide the most benefit for each dollar spent, began an effort in the fall of 2001 to develop a formalized, objective, unbiased pavement selection process. It was envisioned that the revised pavement type selection would be developed through a consensus process by a committee composed of members from the ODOT Office of Pavement Engineering, Ohio/Kentucky Chapter of the American Concrete Pavement Association (now Ohio Concrete Construction Association), Flexible Pavements of Ohio, FHWA, ODOT Office of Construction Administration, ODOT Multi-Lane Coordinator, and ODOT District Offices. The committee held three meetings between September 2001 and May 2002. Shortly after the May 2002 meeting, ODOT management became impatient with the progress being made by the committee and charged the Office of Pavement Engineering with developing a new pavement type selection by July 31, 2002. The first draft of the revised pavement type selection was submitted for industry and FHWA review in August 2002. The revised system was a matrix type of analysis that considered various cost, traffic, and engineering factors objectively. It was based on a concept presented in National Highway Institute (NHI) Course 13114, “Highway Pavements,” and the 1993 AASHTO Design Guide (section 3, chapter 2), as well as suggestions received from Flexible Pavements of Ohio. Each industry provided extensive comments on the first draft. A second draft was issued in December. Again, numerous comments were received. On April 17, 2003, a final version of “Pavement Selection the ODOT Way” was issued. This document is included in appendix A. The controversy over the draft pavement selection documents resulted in the Ohio Legislature including Section 12 of House Bill 87 requiring a NTP review of the pavement type selection process in Ohio.

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ISSUES As the majority of the pavement type selection issues were raised by the industry trade organizations in Ohio, the first step in the review process was to conduct detailed interviews with each of the paving industries. The significant issues raised by each trade organization are summarized in the following sections. Flexible Pavement Industry Issues Flexible Pavements of Ohio was interviewed on September 3, 2003, with a follow-up interview on October 14, 2003. Transcripts were made of these interviews, and they are available on the Internet at http://www.ohiopavementselection.org/. The following were the significant comments and issues raised by Flexible Pavements of Ohio at these interviews:

• The first scheduled rehabilitation for flexible pavements should be revised from 12 to 17 years. Furthermore, the mill and overlay should be limited to the mainline only. Currently, the first rehabilitation is mill and overlay of 1.5 inches. The second mill and overlay should be 14 years after the first rehabilitation and should consist of a 2-inch thick overlay instead of 3.75 inches. Industry feels that the initial pavement design provides adequate structural capacity for the full analysis period.

• The cost analysis should consist of a life cycle cost and a future cost, which should be considered separately.

• The cost analysis would be easier to understand if both initial and life cycle costs had the same weight but different levels of importance (e.g., I=10 initial, I=8 future).

• Spread factors for initial cost, life cycle cost, initial user delay, and future user delay should be 1.0, 0.75, 0.50, 0.25, and 0 to provide a uniform separation.

• There is a need to evaluate engineering and administration costs and relate the percentages to the type of work. Currently, a figure of 7 percent is used by ODOT, and industry believes that this is excessive. The costs for engineering and administration should be commensurate with the complexity of the project.

• There should be an attempt to quantify the actual maintenance of traffic cost (the industry believes that the 10 percent currently applied to all projects may not reflect actual costs).

• Maintenance of traffic, and engineering and administration costs should be added to both the initial costs and the future costs.

• Noise is an important consideration and should be included in the scoring evaluation. Noise should be a scoring factor with an importance of 8 in urban areas and 6 in rural areas. The spread factor should be quantified as follows:

- 0 to 2 decibels of the quietest pavement equals 1. - 2 to 4 decibels of the quietest pavement equals 0.5. - 4 to 6 decibels of the quietest pavement equals 0.25. - 6 to 8 decibels of the quietest pavement equals 0.125. - Greater than 8 decibels of the quietest pavement equals 0.

• Warranty asphalt unit price tables should be based on a trend line of average price. • The price for warranty asphalt for quantities greater than 100,000 cubic yards does not

agree with the source data that ODOT used to develop the tables.

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• User delay should have an importance factor for future maintenance of 3 instead of 6, which gives it the same importance as initial construction user delay.

• The reliability of ride should be increased from 3 to 5, since the measurement of ride quality is standard for pavement construction projects in Ohio.

• Flexible reconstruction projects should be treated the same as rigid pavement reconstruction projects in terms of construction traffic management. In other words, if traffic is diverted to one side for rigid pavements, it should be the same for flexible pavements.

• Step 4 of the pavement selection process should be modified to evaluate other factors, such as bridge construction, that could be the primary factor influencing traffic disruption.

• Revise layer coefficients. - Increase surface and intermediate layers from 0.35 to 0.45 - Revise bituminous base from 0.35 to 0.37 (these revisions would reduce the

required layer thicknesses and, therefore, initial cost). • Recycled asphalt.

- ODOT should review the current limitations on use based on an ODOT study performed by CTL Engineering.

• Break and seat. - ODOT should allow the use of break and seat rehabilitation, based on a study

completed by the University of Cincinnati. Rigid Pavement Industry Issues The Ohio Concrete Construction Association (OCCA) was interviewed on September 4, 2003. A transcript was made of the meeting and is available on the Internet at http://www.ohiopavementselection.org/. The following were the significant comments and issues raised at this interview:

• There is an inherent bias at ODOT that favors hot mix asphalt (HMA). - Bias = systemic familiarity with HMA. - Much of Ohio’s interstate system was built using long jointed reinforced concrete

(JRCP). The JRCP designs still carried several times their initial design traffic. - Many early portland cement concrete (PCC) pavements in Ohio suffer from D-

cracking, which is caused by the deterioration of certain aggregates under freeze thaw conditions. Improved aggregate selection has largely addressed this problem.

• Industry has a major concern with the methods used to estimate initial construction costs for PCC pavements.

- There are insufficient representative projects and geographical diversity to develop an accurate unit cost for life cycle cost analysis (LCCA).

- The unit cost data being used to establish unit costs include non-mainline paving and/or small projects that are not representative of the true costs of concrete pavement construction.

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- The estimating procedure should be similar to that used by contactors and include items such as materials, labor, equipment, and placement costs at a specific project location.

- A shorter time horizon than 3 years should be used for the development of unit prices.

- Unit prices should be developed and published every 6 months. • “Pavement Selection the ODOT Way.”

- The OCCA is not in favor of the scoring system used in this document, preferring decisions based primarily on life cycle cost analysis. There is no basis or documentation for the scoring factors (weight, importance, reliability, spread). OCCA feels that the scoring system is unnecessarily complex and that any system should be readily understandable and transparent.

- User delay costs, not user delay days, should be factored into the LCCA calculations.

- There is no provision for making future changes (e.g., how would you include another pavement type, such as composite pavements?).

- No provision for specification changes. - No factor for pavement-related safety (e.g., rutting, lighting). - Should include routine maintenance in LCCA (e.g., crack sealing, pothole

patching, seal coats, joint sealing). - Due to the limited use of the current PCC pavement design in Ohio, consideration

should be given to using pavement performance data from other agencies to assist in developing the future rehabilitation schedule for concrete pavements.

- ODOT does not plan to review post-bid information to see if their procedure for determining unit prices is valid or to assess the impact of the asphalt price adjustment on the unit price of HMA.

- There is general agreement with the schedule for future rehabilitation for PCC; however, an asphalt overlay should not be required as a structural enhancement at year 32.

- The maintenance repair quantities for PCC pavements at Year 22 are too high. - The initial cost is over-weighted in the decision matrix. - Ride should not be included in the scoring system because it is already accounted

for in the pavement smoothness specifications. - Recycling should not be used as a scoring factor, and even if it is used, the spread

factors for recycling should be the same for PCC and HMA. - Discount rate should be based on factors in Ohio, not OMB A94.

• Pavement design. - The relationship used to convert California Bearing Ratio (CBR) to resilient

modulus may not be appropriate for use in Ohio. - The improvement in the CBR value due to soils stabilization is questionable. - The quantity of undercutting during construction should be less for PCC than

HMA. - Since both pavement types are constructed to the same ride quality specifications,

the same initial serviceability level should be used for both pavement types. - Pavement type selection should be revisited if the projects have been delayed for

any significant time, as the traffic data may be out of date.

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• Construction/specifications. - The asphalt price adjustment provides an unfair advantage to the HMA. - PCC should be considered recyclable. - The method of payment for HMA and PCC should be the same (i.e., by the square

yard for a specified thickness). Currently, HMA is paid by the cubic yard not to exceed planned quantity and PCC is paid by the square yard with a penalty for thickness less than the plan thickness, which results in PCC contractors increasing the quantity of concrete placed to ensure that they are not penalized for low thickness.

Issues Raised by the General Public There was a presentation by two private citizens on tire/pavement noise for PCC pavements at the August 7 meeting of the PSAC. In addition, numerous e-mails were received at the project Web site related to the subject of pavement noise. It is these citizens’ opinion that it will be a disservice to roadway users if pavement noise is not included in the list of pavement selection process criteria.

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PRACTICES OF COMPARISON STATES/PROVINCES Background A major component of this study was to visit 10 highway agencies and to document their pavement type selection procedures to permit comparison with ODOT’s selection process. The selection of the States/Provinces to be interviewed was made in consultation and with the concurrence of the Pavement Selection Advisory Council. Selection of the 10 States interviewed was based on the following criteria:

• Climate similar to Ohio—This evaluation was accomplished using the climatic zones contained in Part III, Section 3.3.5 of the AASHTO Guide for Design of Pavement Structures [1]. As shown in figure 1, the United States is divided into nine regional zones that are formed by the intersection of three moisture regions and three temperature regions. The three moisture regions are:

I. High potential for moisture presence in the entire pavement structure throughout

the year II. Seasonal variability of moisture in the pavement structure III. Very little moisture in the pavement structure during the year

The three temperature regions are:

A. Severe winters with a high potential for frost penetration to appreciable depths

into the subgrade B. Freeze-thaw cycles in the surface and base. Severe winters may produce frozen

subgrade, but long-term freezing problems are minor. C. Low temperatures are not a problem. Stability at high temperature should be

considered.

Pavements within a given climatic zone typically exhibit similarities in performance, moisture-related distress, and drainage-related rehabilitation work required.

• Traffic volumes similar to Ohio—The selected State was to have interstate routes

carrying high volumes of total traffic and truck traffic. • Existence of sizeable metropolitan areas—The selected State was to have several medium

to large urban areas. • Balance of pavement types used—The selected States were to represent a mix of

pavement types on their system. This would include a balance of States that predominately build one type of pavement.

Table 1 provides a list of the States selected for review, along with details concerning their conformance with the selection criteria.

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Figure 1. Climatic zones in the United States [1].

Table 1. States selected for comparison and their conformance with selection criteria.

Interstate System Rank State Climatic Zone

Truck Volumes

Total Traffic

Urban Areas

NHS Divided ≥

4 lanes (Miles)

% ACP

% PCC

% Comp1

1 Illinois I-A High High Large 3408 3.0 25.2 71.8 2 Michigan I-A High High Large 2243 12.3 50.7 37.0 3 Pennsylvania I-A Med-

High High Large 3217 11.0 32.7 56.2

4 Indiana I-A High High Large 1984 7.9 14.4 77.8 5 New York I-A Med-

High High Large 3060 27.7 17.7 54.6

6 Maryland I-B High High Large 1205 88.6 6.2 5.2 7 Wisconsin I-A Med-

High Med High

Medium

2012 0.0 49.5 50.5

8 Ontario I-A High High Large 1286 69.1 6.6 24.2 9 Washington II-A/III-

A/I-C Med-High

High Large 1306 60.4 36.0 2.2

10 Minnesota I-A/II-A Med Med High

Large 1930 12.2 54.7 33.1

1. Includes pavements originally constructed as PCC and overlaid with asphalt concrete (AC) as a rehabilitation activity.

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The highway agency reviews were performed in September and October 2003. Each review consisted of meeting with the person responsible for developing the pavement type selection documentation and/or overseeing its application/use within the agency. During the interview a review questionnaire was completed. The completed questionnaires for each of the agencies are included in appendix C. Copies of manuals containing the agencies’ procedures for pavement type selection were also obtained during the interview. In addition, the agency’s construction specifications, available at each agency’s Web site, were reviewed for information on methods of payment for pavement items and specifications related to the use of recycled materials. A flow chart was developed for each agency summarizing their pavement type selection process. These flow charts are included in appendix B. A spreadsheet was also developed as an aid in comparing each of the agencies procedures with those of ODOT. This spreadsheet is included in appendix D. Agency Pavement Type Selection Processes In our reviews, we found three processes that were being followed. For later reference, we will label them as methods A, B, and C. The processes are described in the following sections. Pavement Type Selection Method A This is the process generally followed by Indiana, Maryland, Washington, Illinois, Wisconsin, and Pennsylvania. This process, which is illustrated in figure 2, consists of two principal steps:

1. Alternatives are developed and LCCA is performed. If the life cycle cost is within a set range, generally 10 percent (Washington 15 percent, Wisconsin 5 percent), the life cycle costs are considered equivalent.

2. Alternatives with equivalent life cycle costs are evaluated subjectively. Factors that may be considered include adjoining pavement types, constructability, traffic control, subgrade support, and traffic volumes. A variation of this method is currently under consideration by Maryland. They are considering a modification to their system, as shown on page B-5, to replace the subjective evaluation of other factors with a matrix driven of evaluation of these factors.

The range of 10± percent at which deterministic life cycle cost values are considered equal is based on the fact that all of the inputs used in the LCCA are estimates with potential for significant variability. Table 2 is from the FHWA Technical Bulletin on Life Cycle Cost [2]. This table highlights the fact that there are no fixed values used when performing a LCCA.

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Figure 2. Pavement type selection method A.

Subjectively Consider otherfactors such as:Scope of Project

Adjoining pavementConstructabilityTraffic ControlCompetition

Make Type Selection

SelectionDocument

Issued

Perform Life Cycle CostAnalysis

Cost within 10% of lowest

estimate

Yes

EliminateAlternativeNo

Identify FeasibleAlternatives

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Table 2. LCCA input variables (from FHWA).

Pavement Type Selection Method B This is the process followed by New York and Ontario. The process is illustrated in figure 3 and involves two principal steps:

1. Each alternative is evaluated to determine if it meets the engineering criteria for the project site.

2. If the alternative satisfies the engineering criteria, preliminary designs are developed and a life cycle cost analysis is performed on each design. The design with the lowest life cycle cost is selected. In the case of Ontario, for projects longer than 10 lane km and annual equivalent single axle load repetitions expected to be greater than 1,000,000 within the next 4 to 5 years, detailed designs for flexible and rigid design are prepared and the pavement type is selected through an alternate bidding process.

LCCA Component Input Variable Source Preliminary Engineering Estimate Construction Management Estimate Construction Estimate

Initial and Future Agency Costs

Maintenance Assumption Timing of Costs Pavement Performance Projection

Current Traffic Estimate Future Traffic Projection Hourly Demand Estimate Vehicle Distributions Estimate Dollar Value of Delay Time Assumption Work Zone Configuration Assumption Work Zone Hours of Operation Assumption Work Zone Duration Assumption Work Zone Activity Years Projection Crash Rates Estimate

User Costs

Crash Cost Rates Assumption Net Present Value Discount Rate Assumption

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Figure 3. Pavement type selection method B.

Perform EngineeringAnalysis

Alternative Satisfies Engineering

Criteria

Develop PreliminaryDesigns

Make PavementType Selection

Issue PavementSelection


Yes

Perform Life CycleCost Analysis

Alternativehas Lowest Life

Cycle Cost


Yes

Project Length > 10 Lane km and ESAL’s > 1,000,000within next 4 to 5 years

Detailed Design PlusDevelopment of

LCCA CostAdjustment Factors

forFlexible/RigidAlternative Bid

Present Designs toPavement Selection

Committee

AlternateBidding

1 rigid Design1 Flexible

Design

Yes

No

ONTARIO

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Pavement Type Selection Method C Pavement type selection method C (figure 4) is the process followed by Minnesota and Michigan. In this process, type selection is based solely on LCCA. In reviewing the flow chart for Minnesota in appendix B, one might get the impression that traffic loadings rather than cost result in the type of pavements selected. Between 1990 and 1995, Minnesota completed life cycle cost comparisons on all projects involving new or reconstructed pavements. In all cases where the design traffic loadings were greater than 7 million, based on bituminous equivalent axle loadings (BESAL’s), they found that the rigid design had the lowest life cycle cost. Where the design BESAL’s were less than 7 million and the subgrade soil R-value was greater than 40, flexible pavement always had the lowest life cycle cost. Therefore, in 1997 it was concluded that performing LCCA on projects falling into these categories was not a worthwhile exercise. In 2001, the process was modified to raise the threshold for determining that all pavements would be a rigid design from 7 million to 10 million BESAL’s. Minnesota has indicated that when the new AASHTO mechanistic/empirical design process is adopted, they will begin performing LCCA on all designs. In Michigan, legislation drives the format of the pavement type selection process. Senate Bill No. 303 of the 1997 Session of the Michigan Legislature contained the following section:

Sec. 1g. The department shall develop and implement a life cycle cost analysis for each project for which total pavement costs exceed $1,000,000 funded in whole, or in part, with state funds. The department shall design and award paving projects utilizing material having the lowest life cycle cost. All pavement design life shall ensure that state funds are utilized as efficiently as possible. (2) As used in this section, “life-cycle cost” means the total cost of the initial project plus all anticipated costs for subsequent maintenance, repair, or resurfacing over the life of the pavement. Life-cycle cost shall also compare equivalent designs and shall be based upon Michigan’s actual historic project maintenance, repair, and resurfacing schedules and costs as recorded by the pavement management system, and shall include estimates of user costs throughout the entire pavement life.

Because of the wording of this section, there are several questionable aspects of the Michigan process. Future costs must be based on the historic performance of pavements in Michigan. In reality, most pavements constructed in Michigan today use different designs and/or materials than were used in the past. For example, in the past Michigan used JRCP; now they are using short jointed plain pavements. Michigan has adopted Superpave mix design and stone matrix asphalt (SMA) design for their HMA pavements. However, none of the expected improvements in performance can be reflected in the LCCA.

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Figure 4. Pavement type selection method C. Neither the Minnesota procedure nor the Michigan procedure considers the variability of the inputs for the LCCA when evaluating their results. In their approach, assumptions, projections, and estimates are used for input, but the results are considered final, no matter how small the difference in the results of the LCCA. Detailed Findings of State Practices Life Cycle Cost Analysis All of the highway agencies interviewed utilize LCCA as part of their pavement type selection. Nine of the States use the net present value approach for calculating the life cycle cost. These States use the same analysis period for all alternatives considered in the analysis. Michigan uses

Develop PreliminaryDesignsAt Least1 Rigid

1 Flexible





Cycle Cost

EliminateAlternativeNoYes

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the equivalent uniform annual cost (EUAC) approach and varies the analysis period for the strategy. The length of Michigan’s analysis period is equal to the service life of the alternative being considered. A summary of the State highway agency practices is provided in the paragraphs below and in table 3. Life Cycle Cost Analysis: All highway agencies interviewed use a life cycle cost analysis that

consists of the sum of initial construction costs and discounted future costs. Ohio does not use the typical LCCA and is not considered consistent with other highway agency practice.

Analysis Period: Ranges from 35 to 60 years, with most agencies using 40 years.

Ohio and Minnesota have the lowest analysis period of 35 years. Ohio is considered consistent with other highway agency practice.

Discount Rate: Discount rates ranged from a low of 3 percent in Illinois to a high

of 6 percent in Pennsylvania. Ohio is using the OMB A94 specified discount rate of 3.2 percent. Ohio is considered consistent with other highway agency practice.

Sensitivity Analysis: Sensitivity analysis is used by only three highway agencies. Ohio

does not currently use a sensitivity analysis. Ohio is considered consistent with other highway agency practice.

Initial Cost: Four agencies, including Ohio, have centrally developed cost data

for LCCA. The other agencies interviewed have project-specific costs or are centrally developed with discretionary adjustments for the LCCA. While there is a similarity in the general practice, several States have addressed life cycle cost issues more rigorously. For example, Wisconsin and Michigan complete a statistical analysis of their unit cost data. If sufficient cost data are not available in a specific project area, the data included in the analysis are expanded until sufficient information is available to develop a confident estimate of the costs. In Minnesota, cost estimates are based on site-specific factors such as materials costs.

LCCA Quantity Adjustment: No agencies surveyed developed or used any adjustment factors to

account for the difference between estimated and as-built quantities. Ohio is considered consistent with other highway agency practice.

Routine Maintenance: Only two agencies include the cost of annual routine maintenance.

Ohio does not include annual routine maintenance in its LCCA, which is considered consistent with other highway agency practice.

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Table 3. State highway agency LCCA practices.

Practices

Illin

ois

Indi

ana

Mar

ylan

d

Mic

higa

n

Min

neso

ta

New

Yor

k

Ont

ario

Penn

sylv

ania

Was

hing

ton

Wis

cons

in

Ohi

o

Use LCCA Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Mod 1

Analysis Period (years) 40 40 40 var.2 35 503 503 40 60 50 35 Discount Rate (%) 3 4 4 OMB4 4.55 OMB4 5.36 6 4 57 OMB4

Sensitivity analysis No 0%-10%

3%-5% No No No ±2% No 2%-

5%8 No No

Initial Cost Centrally developed Yes No Yes Yes9 No No No No No No Yes Project-discretionary No Yes No No Yes10 Yes Yes Yes Yes Yes No Adjust LCCA for as built quantities No No No No No No No No No No No

Routine Maintenance ($/lane mile) Yes11 No No No No No No Yes No No No

Scheduled Maintenance Yes Yes No Yes Yes Yes Yes Yes No Yes No How estimated Com

12 MM13 n/a Hist14 Com

12 Est15 Est15 MM13 n/a MM13 n/a Rehabilitation Cost Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes How estimated Est15 PM16 PM16 PM16 Est15 Est15 Est15 PM16 PM16 PM16 Est15

HMA 1st rehab (years) var.17 Proj18 Proj18 1019 15 15 19 10 15 18 12 2nd rehab (years) var.17 Proj18 Proj18 1319 27 27 31 20 30 Proj18 22 PCC 1st rehab (years) 20

Proj18 Proj18 919 17 15 18 20 20 25 22 2nd rehab (years) none

Proj18 Proj18 1519 27 30 28 30 40 Proj18 32 Residual Value No No No No No No No No No No No Salvage Value No RL20 RL20 No No RL20 RL20 No RL20 RL20 No Const. Traffic Control Initial No No Yes No Yes No No No Yes No No Rehabilitation No No No Yes No No No Yes Yes No Yes Engr. and admin. cost Initial No No No No No No No No Yes No No Rehabilitation No No No Yes No 27% No Yes Yes No Yes User Delay No No Yes Yes Fut21 Fut21 Fut21 Yes Yes No Ind22

Spread of LCCA Considered Equal 10% 10% 10% 0% 0% 0% 0% 10% 15% 5% Var23

Notes: 1. Consider and weigh initial cost and future cost separately. 2. Analysis period varies to match pavement service life. 3. 50 years for new and reconstruction and 30 years for

rehabilitation. 4. Office of Management and Budget Circular A94 5. Currently 4.5% but going to Office of Management and Budget

Circular A94 6. Ministry of Finance social discount rate 7. Set by long standing policy 8. Use a probabilistic analysis 9. Regionally adjusted 10. Not unit cost based. Develop costs based on materials and

construction costs at the specific site. 11. Fixed cost, includes striping, lane delineators, reflectors, etc.

12. Developed by committee 13. Maintenance management system 14. Past history 15. Best estimate 16. Pavement management system 17. Four categories based on traffic 18. Project specific 19. The strategies reflect the overall maintenance approach that

has been used network wide for a specific fix based on historical maintenance and pavement management records.

20. Remaining life 21. Plan to incorporate user delay costs into the life cycle cost

analysis in the near future 22. Consider user delay days in the type selection process 23. 3% initial cost and 10% future cost

18

Scheduled Maintenance: Eight agencies include the cost of regularly scheduled

maintenance, such as crack sealing, joint resealing, and seal coats. Ohio does not include these items in its LCCA and is therefore not considered consistent with other agency practice.

Rehabilitation: All agencies, including Ohio, include the cost of rehabilitation

activities, such as overlays and concrete pavement restoration. Ohio is considered consistent with other highway agency practice.

Time for First Rehabilitation: The year of the first rehabilitation for flexible pavements varies

considerably, from 10 to 19 years, with a median of 15 years. Ohio, at 12 years, is lower than the median.

The year of the first rehabilitation for rigid pavements is highly variable, ranging from 9 to 25 years, with a median value of about 18 years. Ohio currently uses a time to first rehabilitation for rigid pavements of 22 years, which is higher than the 18-year median.

Second Rehabilitation: The year of the second rehabilitation for flexible pavements varies

considerably, from 13 to 30 years, with a median of 27 years. Ohio, at 22 years, is below the median of the other highway agencies.

The year of the second rehabilitation for rigid pavements is highly variable, ranging from 15 to 40 years, with a median value of about 30 years. Ohio currently uses a time to second rehabilitation for rigid pavements of 32 years, which is considered consistent with other highway agency practice.

Method for Rehab Schedule: Six agencies used pavement management data as the basis for the

rehabilitation schedule used in the LCCA and four agencies used engineering opinions. Ohio bases its rehabilitation schedules on engineering opinions.

Residual Value: No highway agencies use residual value in their LCCA. Ohio is

considered consistent with other highway agency practice. Salvage Value: Six highway agencies consider remaining life in the LCCA, so that

each alternative is relatively equal from a condition standpoint at the end of the analysis period. Michigan is included, as their analysis period equals their service life. Ohio does not consider salvage value in the LCCA. The last overlay for flexible pavements is placed at 34 years, while the last overlay for rigid pavements is placed at 32 years. The maintenance schedules currently contained in “Pavement Selection the ODOT Way” result

19

in equal remaining service lives for both pavement types negating the need for consideration of salvage value.

Traffic Control Costs: Only three of the highway agencies interviewed included the cost

of initial construction traffic control costs in their analysis. Ohio is considered consistent with other highway agency practice.

Three of the highway agencies interviewed included the cost of

future rehabilitation construction traffic control costs in their analysis. Ohio does include the cost of future rehabilitation traffic control. However, there is some controversy over the accuracy of these costs.

Engineering and Admin. One highway agency includes the cost of engineering and

administration costs in its initial construction cost estimate for LCCA. Ohio is considered consistent with other highway agency practice.

Three agencies include the costs of engineering and administration

in their cost estimate for future rehabilitation activities. Ohio includes the cost of future rehabilitation engineering and administration costs; however, there is some controversy over the accuracy of these costs.

User Delay: Four highway agencies consider user delay in their LCCA, and

three others are considering including user delay in the future. Ohio does not currently include user delay costs for LCCA.

LCCA Spread Equivalency: Four highway agencies consider life cycle costs within ±10 percent

to be equivalent. One agency uses 15 percent and another uses 5 percent. Four highway agencies use 0 percent. Ohio does not use the typical LCCA.

Pavement Design Practices A summary of the State pavement design practices is provided in table 4 and in the paragraphs below. Flexible Design Design Method: Seven of the highway agencies interviewed use the AASHTO 1993

design procedure. One agency uses the AASHTO 1972 design procedure, one agency uses a modified procedure based on AASHTO data, and one agency uses a mechanistic-empirical procedure. Ohio uses the AASHTO 1993 design procedure.

20

Table 4. State pavement design practices.

Practices

Illin

ois

Indi

ana

Mar

ylan

d

Mic

higa

n

Min

neso

ta

New

Yor

k

Ont

ario

Penn

sylv

ania

Was

hing

ton

Wis

cons

in

Ohi

o

Flexible pavements Design method M-E1 A932 A932 A932 MN3 A934 A932 A932 A932 A725 A932

Design life 20 20 15 20 20 50 20 20 40 20 20 “a” surface n/a .34 .44 .42 n/a .42 .42 .44 .44 .44 .35 “a” intermediate n/a .36 .40 .36 n/a .42 .42 .44 .44 .44 .35 “a” bound base n/a .34 .25 .36 n/a .42 .42 .40 .30 .30 .35

Rigid pavements Design method M-E1 A932 A932 A932 A866 A934 A932 A932 A932 A725 A932

Design life 20 30 25 20 35 50 30 20 40 20 20 PCC Mr (S’c) psi 6507 652 700 670 675 650 7258 6318 650 650 700 PCC Ec psi x 106 3.4 5.0 4.2 4 4.35 4.0 4.2 5.0

Flexible/rigid foundations equal Yes Yes Yes No No Yes Yes No Yes Yes Yes

Initial serviceability same for PCC and HMA n/a Yes No9 Yes n/a n/a10 Yes No9 Yes No11 No12

Notes 1. Mechanistic/empirical design procedure developed in Illinois 2. AASHTO – 1993 version 3. Procedure developed by Minnesota based on AASHO Road Test data 4. Modified procedure based on AASHTO – 1993 version 5. AASHTO – 1972 version 6. AASHTO – 1986 version 7. 14-day center point loading 8. Based on actual field data 9. po = 4.5 for PCC pavements and 4.2 for flexible pavements 10. Not directly considered in the modified procedure 11. Not an input variable in the 1972 Guide where po is fixed in the equation at 4.5 for PCC pavements

and 4.2 for flexible pavements 12. po = 4.2 for PCC pavements and 4.5 for flexible pavements, based on measurements of new pavements

Traffic Design Life: The range is from 15 to 50 years with a median of 20 years. Ohio

uses 20 years and is consistent with the other highway agencies. Asphalt Layer Coefficients: For surface courses, the range was from 0.34 to 0.44 with a median

of 0.42. Ohio currently uses a surface course layer coefficient of 0.35.

For intermediate asphalt courses, the range was from 0.36 to 0.44 with a median of 0.42. Ohio currently uses an intermediate asphalt course layer coefficient of 0.35.

21

For base courses, the range was from 0.25 to 0.42 with a median of 0.36. Ohio currently uses a base course layer coefficient of 0.35.

Rigid Design Design Method: Seven of the highway agencies interviewed use the AASHTO 1993

design procedure. One agency uses the AASHTO 1972 design procedure, one agency uses a modified procedure based on AASHTO data, and one agency uses a mechanistic-empirical procedure. Ohio uses the AASHTO 1993 design procedure.

Traffic Design Life: The range is from 20 to 50 years with a median of about 25 years.

Ohio uses 20 years and is consistent with the other highway agencies.

PCC Modulus of Rupture: The modulus of rupture ranges from 631 to 725 psi with a median

of 650 psi. Ohio uses a modulus of rupture of 700 psi. Based on a limited amount of test data provided for our review, the value of 700 psi appears reasonable.

PCC Modulus of Elasticity The modulus of elasticity (Ec) varies from 3,408,390 to

5,000,000psi. Ohio uses an Ec of 5,000,000. This value is based on testing of concrete on Ohio SHRP Project DEL-23. Further, as shown in figure 5 the impact of Ec on pavement thicknesses designed using the 1993 AASHTO Guide is minimal.

Figure 5. The impact of the elastic modulus of concrete on thickness.

10.7

10.75

10.8

10.85

10.9

10.95

11

2500000 3000000 3500000 4000000 4500000 5000000 5500000Elastic Modulus Concrete, Ec, psi

Pave

men

t Thi

ckne

ss, i

n

Subgrade (K) - 130pci Concrete Strength (MR) – 700psi Load Transfer Coeff. (J) – 2.8 Drainage Coeff. (C) – 1 Initial Serviceability (Po) – 4.2 Terminal Serviceability (Pt) – 2.5 Reliability – 90% Standard Deviation – 0.39 Cumm. 18-kip ESAL’s – 25,000,000

22

Common Design Parameters Foundation Requirements: Seven highway agencies treat the foundation requirements the

same for flexible and rigid pavements. Ohio also treats the foundation requirements the same for both pavement types.

Initial Serviceability: Four highway agencies use the same initial serviceability for both

flexible and rigid pavement types. Three agencies do not use initial serviceability for both pavement types. Two agencies use an initial serviceability value of 4.2 for flexible and 4.5 for rigid pavements. Ohio uses an initial serviceability of 4.5 for flexible and 4.2 for rigid pavements. ODOT indicated that the initial serviceability values used were based on measurements of newly constructed pavements, in conformance with the 93 AASHTO Guide; however the original study could not be located. In late 2002, the State reviewed the serviceability values on one-year old pavements constructed since 1997. The data indicated that the initial serviceability of asphalt pavements was approximately 0.5 higher for flexible pavements than rigid pavements. The study indicated that recently constructed flexible pavements were smoother than rigid pavements and provides support for the initial serviceability numbers being used. Because of the limited nature of the study, ODOT decided not to modify the values being used at this time.

Construction-Related Issues As part of the review, methods of payment and the reuse of salvaged materials were investigated. The findings are summarized in table 5 and discussed in the paragraphs below. Payment for HMA: Eight agencies use tonnage produced as a method of payment for

HMA. Two agencies pay by square yards. Ohio pays for HMA based on a cubic yard using a unit weight conversion factor based on laboratory-measured density.

Payment for PCC: Seven agencies pay for PCC based on plan area. One agency uses

a combination of square yards and cubic yards based on plan area and thickness. One agency uses cubic yards based on plan area and thickness. One agency pays based on plan area and measured thickness up to 0.5 inch over the plan thickness. Ohio pays based on plan square yards and is consistent with the majority of the other highway agencies.

23

Table 5. State pavement construction practices.

Practices

Illin

ois

Indi

ana

Mar

ylan

d

Mic

higa

n

Min

neso

ta

New

Yor

k

Ont

ario

Penn

sylv

ania

Was

hing

ton

Wis

cons

in

Ohi

o

Method of payment Hot mix asphalt sq y ton ton ton ton ton ton sq y ton ton cu y Concrete pavement sq y sq y sq y sq y 1 cu m sq m sq y 2 sq y sq y

Recycling PCC Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Uses 3 sb4 b/sb5 b/sb5 b/sb5 b/sb5 b/sb5 Bf6 g m7 8 gm7

HMA Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Uses HMA HMA HMA HMA HMA HMA HMA HMA HMA 9 HMA

Max % surface 3010 2511 15 1412 3013 20 14 15 2016 2017 2018

Max % intermediate. 3010 2511 2812 5013 20 14 15 2016 3517 3518

Max % base 3010 2511 25 2812 5013 30 30 15 2016 3517 3518

Liq. asphalt price adj. No No Yes No No Yes Yes Yes No Yes Yes Notes: 1. Payment is a combination of sq. yd. plus cu. yd. based on plan quantity 2. Payment is cu. yd based on core thicknesses up to 0.5 over design 3. Capping, subbase, concrete, shoulders, fill 4. Subbase 5. Base and subbase 6. Backfill for structures 7. Granular materials 8. Unbound base (generally) and portland cement concrete (rarely) 9. HMA and unbound base 10. The maximum percentage of RAP is a function of mix design and ranges from 0 percent for an

Ndesign of 105 to 30 percent for an Ndesign of 30 and is not allowed in polymer modified mixes. 11. Up to 15% use grade of asphalt binder specified for the project. 15% to 25% asphalt softer required 12. Percentage is by weight of total binder in the mix. Above 17% binder grade adjustments required 13. Subject to meeting mix design requirements 14. Varies between 10% and 30% 15. Permit 5% to 15%. For mixtures with more than 15 percent RAP, the department evaluates the asphalt

cement content of the RAP source material and determines the grade of the asphalt cement and recycling agent the contractor will be required to use in the final mixture. When RAP is used, a plan to control RAP and procedures to handle the RAP of different compositions must be developed and provided to the department.

16. Up to 20% no new mix design, over 20% required a new mix design 17. Combined RAP and virgin aggregate shall meet percent crushed and natural sand quality requirements.

The blend of new asphaltic material with extracted RAP asphaltic material shall meet the penetration or viscosity requirements for the specified asphaltic material.

18. Whenever more than 10% of reclaimed asphalt concrete pavement is used it must be included in the mix design to establish the job mix formula and conform to the requirements of the specified asphalt binder for the asphalt binder proposed for use in the mixture, by the combination of reclaimed asphalt, virgin asphalt, and rejuvenating agents. A maximum of 10% RAP is allowed in polymer modified surface mixtures.

24

Liquid AC Price Adjustment: Five highway agencies use a liquid AC price adjustment. Ohio

uses a liquid AC price adjustment. PCC Recycling: All highway agencies interviewed permit the use of recycling PCC

on the project. Generally, the recycled materials must meet the specification requirements for which the material is being substituted. In most agencies, the PCC material removed from the project becomes the property of the contactor who uses this material for other non-highway agency projects. Ohio is consistent with the practices of the other States.

HMA Recycling: HMA recycling is permitted by all highway agencies interviewed.

All agencies permit the use of recycled asphalt pavement (RAP) in HMA from 10 to 30 percent. For amounts ranging from 10 to 20 percent, mix design adjustments are not generally required. Above these values, the HMA must meet the requirements of virgin HMA. Ohio permits varying amounts of RAP in new HMA mixes.

25

FHWA AND AASHTO GUIDANCE FHWA Policy and Guidance The FHWA’s policy on pavement design and type selection is contained in Part 626 of Tile 23 of the Code of Federal Regulations.

Sec. 626.1 Purpose. To set forth pavement design policy for Federal-aid highway projects. Sec. 626.2 Definitions. Unless otherwise specified in this part, the definitions in 23 U.S.C. 101(a) are applicable to this part. As used in this part: Pavement design means a project level activity where detailed engineering and economic considerations are given to alternative combinations of subbase, base, and surface materials which will provide adequate load carrying capacity. Factors which are considered include: Materials, traffic, climate, maintenance, drainage, and life-cycle costs. Sec. 626.3 Policy. Pavement shall be designed to accommodate current and predicted traffic needs in a safe, durable, and cost effective manner.

As written, the policy provides a broad framework under which the State highway agencies are required to operate. The regulation does not specify procedures to be followed to meet this requirement. Instead, each highway agency is expected to use procedures that are appropriate for their conditions. In a non-regulatory supplement, the FHWA provides the following additional guidance on pavement type selection:

4) Engineering Economic Analysis. The design of both new and rehabilitated pavements should include an engineering and economic evaluation of alternative strategies and materials. The project specific analysis should be evaluated in light of the needs of the entire system. The "1993 AASHTO Guide for Design of Pavement Structures" (Appendix B) and the "FHWA Pavement Rehabilitation Manual," provide guidance on engineering considerations. The engineering evaluation should include consideration of the use of recycled materials and/or pavement recycling techniques, where feasible. Economic considerations include an economic analysis based on Life Cycle Costs (LCC). The FHWA Final Policy Statement on LCC analysis published in the September 18, 1996, Federal Register provides guidance on LCC Analysis. The FHWA Memorandum "National Highway System Designation Act - Life Cycle Cost Analysis Requirements" (April 19, 1996), provides supporting information and guidance to assist in

26

implementing Life-Cycle Cost Analysis (LCCA) requirements in the National Highway System (NHS) Designation Act of 1995. The FHWA Office of Pavement Technology's "Interim Technical Bulletin: Life Cycle Cost Analysis in Pavement Design FHWA-SA-98-079, September 1998" and FHWA's "Demonstration Project 115: Probabilistic Life Cycle Cost Analysis in Pavement Design" provide technical guidance and training on good practice. (a) Pavements are long-term public investments and all the costs (both agency and user) that occur throughout their lives should be considered. LCCA identifies the long-term economic efficiency of competing pavement designs. However, the resulting numbers themselves are less important than the logical analysis framework fostered by LCCA in which the consequences of competing alternatives are evaluated. When performing LCCA for pavement design, the variability of input parameters needs to be considered. The results of LCCA should be evaluated to determine whether differences in costs between competing alternatives are statistically significant. This evaluation is particularly important when the LCC analysis reflects relatively small economic differences between alternatives. (b) The FHWA's policy on alternate bids, which would include bids for alternate pavement types, is addressed in 23 CFR 635.411(b). This section requires the use of alternate bid items "When ... more than one... product... will fulfill the requirements... and these... products are judged...equally acceptable on the basis of engineering analysis and the anticipated prices... are estimated to be approximately the same.

(1) The FHWA does not encourage the use of alternate bids to determine the mainline pavement type, primarily due to the difficulties in developing truly equivalent pavement designs. (2) In those rare instances where the use of alternate bids is considered, the SHA's engineering and economic analysis of the pavement type selection process should clearly demonstrate that there is no clear cut choice between two or more alternatives having equivalent designs. Equivalent design implies that each alternative will be designed to perform equally, and provide the same level of service, over the same performance period and have similar life-cycle costs.

In reading the policy and supplement guidance, the conclusion can be drawn that both engineering factors and LCCA should be considered in selection pavement alternatives. They further highlight the non-deterministic nature of LCCA in their supplemental guidance when they state:

When performing LCCA for pavement design, the variability of input parameters needs to be considered. The results of LCCA should be evaluated to determine

27

whether differences in costs between competing alternatives are statistically significant.

A number of highway agencies recognize the uncertainty and variability of LCCA and have adopted a spread factor to account for these differences. For example, if the life cycle costs of two alternatives are within a certain percentage of each other (e.g., 10 percent), they are considered equal in terms of life cycle cost. The guidance is also clear that the FHWA discourages the use of alternate bidding as a routine means of pavement type selection. One of the primary problems with the bidding of pavement alternates is that the contract may not be awarded to the contactor with the lowest bid for initial construction. Because the two pavement types have different rehabilitation costs, the contractor’s bid incorporates the bid for construction plus a valuation for future rehabilitation costs. The valuation for future costs is a value determined by the agency based anticipated performance. However, over the past 7 years a number of agencies have expressed the desire to utilize alternate bidding. This interest developed as a result of both the agencies’ and industries’ desire to foster additional competition. The FHWA has accommodated this desire by incorporating alternative pavement design bidding under Special Experimental Project No. 14 (SEP-14), Innovative Contracting Practices. The objective of SEP-14 is to evaluate contracting processes that have the potential to reduce life cycle costs, while at the same time maintain quality. Missouri (5 projects), Kentucky, Louisiana (7 projects), Michigan (2 projects), and Maryland have used alternate pavement bidding procedures under SEP-14. AASHTO Guidance AASHTO’s guidance on pavement type selection is found in appendix B of the AASHTO Guide for Design of Pavement Structures [1]. Figure 6 outlines the pavement selection process contained in the Guide. The Guide lists factors that may have some influence on the decision-making process. These factors are placed into two groups. Principal factors are those factors that may have a major influence and may dictate the pavement type in some instances. Secondary factors include those factors that have a lesser influence and are taken into account when there are no overriding considerations or one type is clearly not superior from an economic standpoint. The principal and secondary factors are listed below:

Principal Factors 1. Traffic. 2. Soils characteristics (problem soils). 3. Weather. 4. Construction consideration (stage construction, maintenance of traffic). 5. Recycling (opportunity to recycle from existing pavement or future opportunities). 6. Cost comparison.

28

1. Are thereoverridingprincipal factorswhich dictatepavement type

2. Developpreliminarydesigns fortypical sections

3. EconomicAnalysis oftypical sections.Is one typeclearly superior?

4. Evaluatesecondaryfactors

8. Select finalpavement typeand design

7. Is designreasonably closeto typical designused in analysis

6. Performdetailedpavementdesign

5. Preliminarypavement type

selection

No

Yes

No

Yes

Yes

No

Figure 6. Pavement type selection process (figure B.1, AASHTO Guide).

Secondary Factors 1. Performance of similar pavements in the area 2. Adjacent existing pavements 3. Conservation of materials and energy 4. Availability of local materials or contractor capabilities 5. Traffic safety 6. Incorporation of experimental features 7. Stimulation of completion 8. Municipal preference, participating local government preference and recognition of local

industry

29

CONCLUSIONS AND RECOMMENDATIONS This study called for a review and analysis of ODOT’s pavement type selection process. The primary benchmark for the analysis was to be based on comparing and contrasting Ohio’s process with those used by other highway agencies and recommendations of AASHTO and the FHWA. The NTP team visited 10 highway agencies and reviewed and discussed their processes. When reviewing the practices of other highway agencies, we tried to identify advantages and disadvantages with specific aspects of their systems. We also consulted the trade organizations in a number of the States to get their views on pavement type selection. The team has reviewed the written guidance provided by AASHTO and the FHWA. In addition, we have had informal discussions with FHWA officials in their Ohio Division Office and the Pavement Division and Contract Administration Group in the headquarters Office of Infrastructure. Conclusions As the review of the highway agencies indicated, there are many and diverse approaches to the pavement selection process. The team’s approach was to extract and evaluate, from the highway agencies visited, those attributes that address issues in Ohio. Further, we attempted to comply as closely as possible with the recommendations of both AASHTO and FHWA. ODOT has attempted to develop an objective process that will eliminate second-guessing of their project-level decisions, by industry or other affected groups. As we have observed in Ohio and other highway agencies that have objective systems, the affected pavement industries realize that every detail in the process may have a significant impact on their future ability to obtain work in Ohio. This is in contrast to a more subjective system followed by a majority of the highway agencies interviewed, where, when net-present value is approximately equal, the highway agency has more flexibility in choosing secondary factors to help make the decision on pavement type. While in our opinion the Department has the sole authority to develop and implement a pavement type selection procedure, it is imperative that both the public and the pavement industries perceive the process as unbiased. In the development of an objective type selection process it is important that the agency and the paving industries work together to try and reach some type of accord on the factors being considered. From what we have observed, coupled with the history and issues raised, this will be difficult in Ohio. The problem with this type of controversy is that it can lead to direction from outside sources. One avenue that is often pursued is a legislative remedy. This has been tried in the past, often with less than satisfactory results. One example was Section 1038(d) of the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA), which mandated the use of quantities of asphalt pavement containing recycled rubber. This Section also contained specific penalties for those States unable to certify to the annual usage requirement. Section 205(b) of the NHS Designation Act of 1995 amended Section

30

1038 by striking subsection (d) eliminating the crumb rubber mandate and all associated penalties. One of the consequences of the Act was the inappropriate (from an engineering standpoint) application of the material resulting in excessive costs and in some cases to premature pavement failure. The problems encountered during the time of the mandate hampered implementation after the mandate ended. In addition, the mandate caused political fallout within the rubber asphalt industry and thus created a rift from its parent industry. The issue of systemic bias raised by OCCA was not something that the NTP believes can be solved through technical modifications of the selection process. This must be addressed by the OCCA through effective marketing, education, product improvement, etc. Recommendations Based on all the above considerations, the NTP makes the following recommendations concerning the pavement type selection process in Ohio. Recommendation #1—Improve Communication Both the pavement industry and ODOT need to make a strong commitment to implement a plan to improve communications. The assertions of bias, legislative involvement, and the large number of detailed issues raised by both industries, indicate a need to improve the communication process. We strongly encourage that all parties minimize the level of rhetoric and establish a more effective approach to address the many detailed issues that arise relative to pavement design, construction, and type selection. It is apparent that this will not be an easy recommendation to implement. As a first step we recommend that a facilitator be used to conduct meetings between industry and ODOT. The facilitator would work with the participants to develop a common understanding of the issues, to understand the interests of all the parties, to identify and evaluate solutions and to create an agreement that parties can implement. Meetings should be held on a regularly scheduled basis. The meetings should focus on technical issues. Industry suggestions should be supported with facts/data, and ODOT responses should also be supported by facts/data. The primary ODOT participants should be those technical managers responsible for pavement design and pavement type selection. We would expect the use of a facilitator to be limited to approximately 6 one- to two-day meetings occurring during calendar year 2004. A scope of work for obtaining and selecting a facilitator is included in appendix F. Implementation—Facilitator selected and meetings initiated during the first quarter of calendar year 2004. Benefit—The benefit of implementing Recommendation #1 is that it will promote a more productive interaction between ODOT and the paving industries. It will provide a forum more conducive to addressing and resolving pavement design, pavement type selection, and specification issues. It is believed that many of the technical issues raised by the paving

31

industries during the NTP interviews could have been resolved if there was an effective communication system in place. Recommendation #2—Adopt a Modified Pavement Type Selection Procedure This recommendation consists of modifying “Pavement Selection the ODOT Way” to more closely follow a management decision-making process. In the recommended process, the primary and secondary engineering factors and the economic factors would be evaluated. Rather than basing a decision on the absolute values developed by the process, the manager responsible for pavement type selection would weigh all the factors and make a decision. The current system has most of the components in place, and the intent of this recommendation is to strengthen certain aspects of the process and provide ODOT managers with needed flexibility. The NTP does not believe ODOT’s current procedure is so flawed that pavement selection should be deferred pending implementation of a new process. Rather, we would expect that recommended modifications to the process will occur incrementally over the next 12 months. Based on our review of the practices used by other highway agencies and the recommendations of AASHTO and FHWA, it is recommended that ODOT modify its pavement type selection procedure to follow the process shown in figure 7. This procedure is a modification of method A (see figure 2). The modifications are based on the AASHTO procedure outlined in figure 6. The key components of the procedure are as follows:

1. Complete an engineering review and analysis of the principal factors (as defined by AASHTO and ODOT) to determine which pavement alternatives are feasible for the project site.

2. Perform a LCCA in accordance with Recommendations 2a thru 2f below.

3. Evaluate the differences in life cycle costs between the various alternatives. This

evaluation should consider the uncertainty and variability of the input factors used in the LCCA. Because of the uncertainty and variability in input factors, when the life cycle cost of an alternative is within 10 percent of the lowest life cycle cost alternative, they should be considered equivalent. The value of 10 percent is the typical value used by other highway agencies in evaluating equivalent costs. It is expected that the appropriateness of the 10 percent value will be better addressed as more highway agencies apply the probabilistic approach to LCCA outlined in FHWA’s Technical Bulletin on Life-Cycle Cost Analysis in Pavement Design [2].

At ODOT’s discretion, an industry review of the LCCA would be appropriate at this time. This review would be primarily for the purpose of insuring that appropriate input factors used in the analysis are appropriate for the specific project.

4. For those alternatives with equivalent life cycle costs as defined above, an engineering

analysis of the secondary factors as identified by AASHTO and ODOT should be completed. This process could follow a matrix type approach similar to the one currently being used in ODOT’s type selection process.

32

Figure 7. Recommended pavement type selection procedure for Ohio.


Identify Alternatives

Engineering Review ofSecondary Factors

Consider all factors related toengineering performance andcost and make a pavement

type selection

SelectionDocument

Issued


estimate

Yes


Engineering Reviewand Analysis of thePrincipal Factors

Is theAlternativeFeasible?

Yes


Industry review of LCCAfor accuracy

MeetsEngineering

Criteria

Yes


33

5. Upon completion of the secondary analysis those alternatives identified as being

essentially equivalent from both engineering and LCCA standpoint would be evaluated. If the alternatives being evaluated are considered equivalent, it would be appropriate to consider factors such as first cost, minor differences in life cycle cost, or uncertainty about the expected level of performance.

Implementation—It is expected that the decision-making process outlined above can be implemented for all pavement type selections (on major rehabilitation projects longer than 4 lane miles calling for new or reconstructed pavements) made after January 1, 2004, using the data currently being developed for use in “Pavement Selection the ODOT Way.” Incremental improvements in the development of the data used in the pavement selection process are expected to occur over the following 12 months. The NTP expects that over time ODOT may also find it necessary to make modifications to the process to meet their management needs. Benefit—While the “Pavement Selection the ODOT Way” process is objective in its application, it is composed entirely of subjective factors. The NTP-recommended process recognizes the subjectivity of pavement type selection. It permits ODOT management to weigh the engineering and economic factors on a project-by-project basis, permitting site conditions to be addressed. The recommended process fully complies with the recommendations of AASHTO and FHWA. The following are recommended modifications to strengthen the process: Recommendation #2a—Adopt a Traditional LCCA Approach The factors for initial construction and future maintenance should be eliminated and combined into one factor, life cycle cost. The LCCA should calculate a net present value that includes an initial cost comprised of all differential agency costs between the pavement alternatives and the total discounted future agency costs including all expected contract resurfacing and rehabilitation work. Where the remaining lives of the alternatives being considered are not equal, a salvage value based on remaining life should be included in the analysis. This type of LCCA is used by all of the 10 highway agencies interviewed. Implementation—Traditional LCCA is expected to be used on all pavement type selections made after January 1, 2004. The data currently being used to estimate current and future costs can be used as input for the initial implementation of the LCCA, with recommended improvements to the data occurring incrementally. Benefit—Adoption of a traditional LCCA approach will provide a process that is more transparent and easier to explain and understand than the weighting system currently used to evaluate current and future costs.

34

Recommendation #2b—Develop Pavement Survival Curves to Better Establish Pavement and Overlay Lives for Use in LCCA The State should undertake a program to utilize pavement survival curves for Ohio pavements to evaluate and adjust the maintenance and rehabilitation schedules in their LCCA. ODOT should critically review the features of its pavement management database to ensure that the database will support the continued development and updating of project-related survival curves. The survival curves should reflect the current designs that are being used, age and traffic, etc. Examples of agencies that have developed survival curves include Illinois [3] and Ontario [4]. Other highway agencies that have reported using survival curves include Wisconsin and Michigan. During the course of the review it was suggested that the NTP undertake the development of survival curves. However, it was determined that ODOT had an ongoing research project, “Evaluation of the Variation in Pavement Performance Between ODOT Districts,” that includes the development of an informational database of all relevant pavement performance data and analysis procedures that will allow for the development and updating of pavement survival curves. This work is scheduled to be completed in April 2004. Appendix E contains a discussion on the application of survival curves. At the request of the PSAC, the NTP explored the development of interim maintenance schedules for use in the LCCA pending the implementation of Recommendation 2b. The results of the NTP’s analysis are contained in appendix G. Based on this analysis, the NTP believes the schedules currently included in “Pavement Selection the ODOT Way” are suitable for use on an interim basis. However, based on the practices followed by ODOT during the last 5 years, the NTP recommends that the width of planing for the 1.5-inch functional overlays of flexible pavements be reduced to mainline only. Implementation—Within 6 months of the completion date of the research project, ODOT will adjust the pavement rehabilitation schedules in the LCCA procedure to reflect the expected performance of Ohio pavements. Benefit—Developing and maintaining survival curves for pavements constructed in Ohio will provide the basis for developing logical and defensible pavement maintenance and rehabilitation schedules for Ohio pavements. Although this recommendation will require a commitment of resources to implement, it will eventually form the basis for most of the inputs required to evaluate future costs in the LCCA. The survival curves will also provide a benchmark for measuring the effectiveness of design changes or the implementation of new technologies. Recommendation #2c—Continue to Use the OMB A94 Discount Rates The OMB A94 30-year real discount rate should continue to be used in the LCCA. This is the rate recommended in FHWA’s Technical Bulletin on Life-Cycle Cost Analysis in Pavement Design, dated September 1998 [2].

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All of the highway agencies reviewed are using the discount rate contained in OMB A94 or one closely paralleling that rate (3 to 6 percent). Benefit—The OMB A94 discount rate is widely accepted for LCCA and is easily defended. The development and basis of this rate is described in the circular prepared by OMB. Recommendation #2d—Evaluate the Application of Engineering and Administration Costs and Traffic Maintenance Costs in LCCA ODOT should not include the current 7% engineering and administration and 10% traffic maintenance costs in their LCCA. There are questions relative to proportion of these factors directly applicable to the pavement portion of a project and whether the percentage should vary by the type of rehabilitation work. The majority of highway agencies interviewed do not consider maintenance of traffic costs and engineering and administration costs in their LCCA. Most agencies consider these costs to be equal for each pavement type or the difference is considered to be insignificant between pavement types. Implementation—This recommendation is expected to be incorporated into all pavement type selections performed after January 1, 2004. In the future, ODOT may wish to reconsider application of these factors as the LCCA process matures and improvements are made to the cost database. Benefit—There has been controversy over the magnitude of the maintenance of traffic and engineering and administration costs that should be included in LCCA. Removal of these factors, pending the future availability of conclusive data to develop the factors, eliminates controversy over factors that many other States are not including in their analysis. Recommendation #2e—Develop Alternate Methods of Determining Unit Costs for PCC Until such time as ODOT has an adequate number of PCC projects to provide reliable unit costs for PCC pavements, ODOT should evaluate alternative procedures for developing initial cost estimates for PCC pavements. Because of the limited number of projects being constructed in Ohio, there is the possibility that cost estimates for some locations in the State may not be accurate. In areas where sufficient unit cost data are not available, it is recommended that estimating processes that consider the differences in materials or labor costs be used to adjust statewide unit prices for that area. Implementation—Full implementation of this recommendation is expected within 6 months. In the interim, it is recommended that ODOT solicit industry comments on the unit costs being incorporated into the LCCA. Benefit—Estimated initial cost is one of the most significant factors in LCCA. Improvement in procedures for estimating initial cost will make LCCA a more effective tool for managing the limited resources available for highway construction.

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Recommendation #2f—Develop User Delay Costs Procedure Four of the highway agencies that were interviewed are using (and three are developing) user delay models to include in their LCCA. It is recommended that ODOT undertake a research project develop a user delay cost procedure for incorporation in its LCCA. Since this research may take several years, in the interim, it is recommended that the current ODOT method of determining user delay days be used as a secondary factor in the pavement selection process. As indicated in FHWA’s Interim Technical Bulletin on LCCA [2] the decision to include or exclude user costs can significantly affect LCCA results. They describe several approaches for considering user costs, including consideration of the combined agency and user costs, as well as the separate evaluation of user costs. Development work for the user cost element of the LCCA process should include a state-of-the-art review of the various State practices for incorporation of these costs into the analysis process. Implementation—This is a long-term effort expected to take 1 to 3 years for full implementation. Benefit—Including user delay costs in the LCCA ensures that the impact on the highway user is considered during the pavement design process. With the advent of techniques such as just-in-time delivery, even minor impacts on traffic flow can have an adverse impact on the local economy. Recommendation #3—Implement Alternative Bidding Trial Projects Because of the issues raised relative to the lack of reliable unit costs for PCC pavements, we recommend that ODOT utilize FHWA Special Experimental Project 14 (SEP-14), Innovative Contracting Practices, to let (sell) a number of alternative pavement bidding projects over the next 2 years. It is recommended that 5 to 10 projects involving new or reconstructed pavements be selected for this effort. Projects selected should be those for which there are no significant engineering reasons for selecting a specific pavement type and the estimated life cycle costs show a difference of less than 10 percent. Projects selected should be on Interstate routes or non-Interstate routes with greater than 35 million rigid ESAL’s for the 20-year design period or average daily traffic (ADT) greater than 30,000 vehicles/day, based on the most recent Traffic Survey Report and be approximately 5 centerline miles or greater in length. At least five States have utilized alternative pavement type bidding under SEP-14. Its use is recommended for Ohio as a means of addressing issues raised regarding the development of initial cost estimates in the life cycle cost analysis. Michigan, Missouri, and Louisiana have used the process on a number of projects and have documentation on specifications and procedures followed. The Province of Ontario is also using the alternative bid process. ODOT should consult with these highway agencies to assist in establishing the most appropriate alternative bid process for Ohio. The typical approach followed by each of the agencies is to develop a life cycle adjustment factor for each of the pavement alternatives to be bid. The life cycle adjustment factor is a fixed-dollar amount added to each bid and is based on the agencies’ estimate of the net present value of future rehabilitation work to be performed over the analysis

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period for each alternative. Since a certain amount of consensus with industry will be required to accomplish this, facilitated meetings are recommended. Because of the increased engineering costs involved in developing plans for alternative bidding and the ongoing controversy that will arise in applying future costs to the contract bids, the NTP is not recommending that the use of alternative bid be adopted as a routine practice or extend beyond a maximum of 10 projects. Implementation—This recommendation is expected to be accomplished during calendar years 2004 and 2005. Benefit—This recommendation will go a long way toward improving the cost competitiveness of the two pavement types in Ohio. Alternative bidding provides a means of insuring that Ohio gets the most cost-effective pavement on major projects. It will also address the issue of appropriate initial costs for use in LCCA. Recommendation #4—Address Pavement-Tire Noise Issues ODOT should undertake a review to determine which noise mitigation techniques will ensure that future pavements provide suitable noise levels to adjacent property owners and motorists. Further, test sections should be constructed to verify the suitability of the techniques. Pavement-tire noise is an issue that ODOT should address. Based on experience in other highway agencies, the concerns raised by a number of citizens in Ohio are real. There are four methods currently being used by agencies to address pavement-tire noise. They are as follows:

• Overlaying with open-graded HMA. • Performing longitudinal tining of the PCC surface. • Using the random transverse spacing developed in Australia. • Using a random-spaced tining pattern developed in Wisconsin.

According to the FHWA, there has been good success with the first three techniques and varied success with the Wisconsin random tining concept. Good results with the longitudinal tining concept have been reported by California, Michigan, Kansas, and Colorado. The tining spacing and size is critical in reducing noise on PCC-surfaced pavements. Diamond grinding has also been shown to reduce the tire pavement noise levels on existing pavements. FHWA is currently developing a Technical Advisory on this subject and may be able to provide additional guidance. Implementation—The full study is expected to take approximately 2 years. In the interim, the most promising techniques, based on FHWA recommendations should be incorporated into noise sensitive projects. Benefit—There are techniques available to address the pavement-tire noise issue at little or no additional first cost. Addressing the pavement-tire noise issue after the fact can lead to large expenditures by the highway agency to mitigate the problem.

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Miscellaneous Issues Table 6 contains a listing of a number issues raised by the industries during our review. The types of issues raised are of the type that we would normally expect States and industry to resolve in a fairly routine basis through effective communication. We have provided a recommendation for each item; however, we believe further communication between ODOT and the affected industry would be appropriate.

Table 6. Issues that should be resolved by ODOT and Industry on a routine basis.

Issue Recommendation 1. Warranty asphalt unit price tables should be

based on a trend line of average price. The price for warranty asphalt for quantities greater than 100,000 cubic yards does not agree with the source data that ODOT used to develop the tables.

It is recommended that the asphalt unit price tables should be based on a trend line of average prices and the apparent discrepancy for quantities greater than 100,000 cubic yards be resolved.

2. Flexible reconstruction projects should be treated the same as rigid pavement reconstruction projects in terms of construction traffic management (i.e., if traffic is diverted to one side for rigid pavements, it should be the same for flexible pavements).

Limited Concurrence. The evaluation of traffic management plans was felt to be outside the scope of the NTP’s review. However, this is an area of continued disagreement and therefore, the NTP recommends that ODOT establish procedures for evaluating each flexible reconstruction project and determining the most advantageous traffic management plan from the standpoint of construction operations and user safety and convenience.

3. Suggest that Step 4 of the pavement selection process be modified to evaluate other factors such as bridge construction that could be the primary factor influencing traffic disruption.

We concur.

4. Revise layer coefficients Surface and intermediate layers -increase from 0.35 to 0.45.

Bituminous base from 0.35 to 0.37 (these revisions would reduce the required layer thicknesses and, therefore, cost).

Layer coefficients should be increased in accordance with the study recently completed for ODOT by the University of Toledo and an AASHTO Bulletin Board survey. The increase is supported with data, generally conforms to the 1993 AASHTO Guide, and follows practices of other States.

5. Recycled asphalt ODOT should review the current limitations on use based on a study done for the ODOT completed by CTL Engineering.

We do not concur. While many States may appear more liberal, most require recycled mixes to meet the same specification as virgin mixes for surface courses on high volume routes. This is an area where further discussion between ODOT and industry appears warranted.

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Table 6. Issues that should be resolved by ODOT and Industry on a routine basis (continued).

Issue Recommendation

6. Break and seat ODOT should allow the use of break and seat rehabilitation based on a study completed by the University of Cincinnati.

Recommend further study. Break and seat has very limited use. This item is not in the scope of work of the NTP study.

7. The relationship used to convert CBR to resilient modulus may not be appropriate for use in Ohio.

We do not concur. The current method used to convert CBR to resilient modulus is within the range recommended in the AASHTO 93 Design Guide.

8. The improvement in the CBR value due to soils stabilization is questionable.

We do not concur. No data were presented that indicated that the long-term durability of soils stabilization is a problem in Ohio. The State indicates they currently do not increase CBR when soil stabilization is performed.

9. Since both pavement types are constructed to the same ride quality specifications, the same initial serviceability level should be used for both pavement types.

We do not concur. ODOT’s selection of initial serviceability is based on measurement of completed pavement sections. We recommend that ODOT develop a process for continually monitoring the ride of newly constructed pavements and update the initial serviceability value annually based on this process.

10. Pavement type selection should be revisited if the projects have been delayed for any significant time, as the traffic data may be out of date.

We do not concur. It would be prudent to verify the pavement designs for substantial differences in traffic expected from the original design values. Generally, time constraints and designs costs would preclude repeating the pavement type selection.

11. The asphalt price adjustment provides an unfair advantage to the HMA.

NTP makes no recommendation on this issue. The current stability of asphalt prices makes this a minor issue at this time. Asphalt prices adjustments are used by half of the highway agencies interviewed.

12. PCC should be considered recyclable. ODOT specifications relative to the use of recycled concrete generally conform to the practices of the States reviewed. FHWA is currently reviewing the use of PCC materials and may provide further guidance on this issue.

13. Method of payment for HMA and PCC should be the same (i.e., by the square yard for a specified thickness). Currently, HMA is paid by the cubic yard not to exceed planned quantity. PCC is currently paid by the square yard with a penalty for thickness less than the plan thickness, which results in PCC contractors increasing the quantity of concrete placed to ensure that they are not penalized for low thickness.

We do not concur. The method of payment used by ODOT is in general conformance with that used by other highway agencies.

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REFERENCES 1. American Association of State Highway and Transportation Officials, AASHTO Guide for

Design of Pavement Structures, Washington, D.C., 1993.

2. J. Walls, III, and Michael R. Smith, Life-Cycle Cost Analysis in Pavement Design Interim Technical Bulletin, FHWA-SA-98-079, Washington, D.C., 1998.

3. N.G. Gharaibeh and M.I. Darter, Longevity of Highway Pavements In Illinois—2000 Update, Final Report FHWA-IL-UI-283, Illinois Department of Transportation, Springfield, Illinois, 2002.

4. K.L. Smith, N.G. Gharaibeh, M.I. Darter, H.L. Von Quintus, B. Killingsworth, R. Barton, and K. Kobia, “Review of Life Cycle Costing Analysis Procedures” (in Ontario), Final Report prepared for the Ministry of Transportation of Ontario, Toronto, Ontario, Canada, 1998.

5. A. Bradbury, T. Kazmierowski, K.L. Smith, and H.L. Von Quintus, “Life Cycle Costing of Freeway Pavements in Ontario,” paper presented at the 79th Annual Meeting of the Transportation Research Board, Washington, D.C., 2000.

Appendix A

“Pavement Selection the ODOT Way”

APPENDIX A

A-1

The ODOT Way Pavement Selection Scoring System Draft 4/17/03

Wt. = Weight Imp. = Importance Rel. = Reliability Total possible points = 4500

Scoring Category Wt. Imp. RelAvailable Points

Life-Cycle Cost Spread 0-3% 3.01-6% 6.01-10% 10.01-15% >15%Initial Cost 40 8 5 Points 1 0.8 0.5 0.3 0 1600

Spread 0-10% 10.01-20% 20.01-30% 30.01-40% >40%Future Maint. Cost 25 8 2 Points 1 0.8 0.5 0.3 0 400

User Delay Spread 0-25% 25.01-50% 50.01-75% 75.01-100% >100%Initial Construction 30 3 3 Points 1 0.8 0.5 0.3 0 270

Spread 0-25% 25.01-50% 50.01-75% 75.01-100% >100%Future Maintenance 30 6 2 Points 1 0.8 0.5 0.3 0 360Constructability 20 7 3Subgrade Unbonded Concrete Overlay and Whitetopping = 1.0 420

New pavement and pavement replacement, all types = 0.7Rubblize and Roll, and Crack and Seat = 0.6

Drainage 20 2 4 New pavement and pavement replacement, all types = 1.0 160Unbonded Concrete Overlay, Whitetopping, Rubblize and Roll, and Crack and Seat 0.8

Uniformity of X-section 20 6 5 If no widening: All alternatives = 1.0 600If widening (permanent lane addition):New pavement and pavement replacement, all types = 1.0Rubblize and Roll = 0.8Unbonded Concrete Overlay, Whitetopping, and Crack and Seat 0.6

Maintenance of Traffic 20 7 3 Alternatives with an advantage = 1.0 420Alternatives with a disadvantage = 0.5When no alternative has any advantage, all alternatives

EnvironmentRecycle-ability 10 3 4 New Flexible and Flexible Replacement = 1.0 120

Rubblize and Roll = 0.9Crack and Seat = 0.8New Rigid, Rigid Replacement, and Whitetopping = 0.7Unbonded Concrete Overlay = 0.3

Ride 10 5 3 All asphalt alternatives = 1.0 150JAII concrete alternatives = 0.7

Spread Factors

APPENDIX A

A-2

Pavement Selection the ODOT Way 4-17-03

The Purpose of Pavement Selection

The Pavement Selection Committee (PSC) is charged with selecting pavement type for new pavements and major rehabilitations. This authority is granted by the Pavement Design and Selection Process (Policy 515-002(P)). The selection of pavement type is not a simple one as the competing products both have advantages and disadvantages and both can provide excellent service for many years. This document describes the process the Ohio Department of Transportation (ODOT) uses to select pavement type.

There are many factors to be considered when selecting pavement type. Some factors relate to all projects, others may be project specific or may have varying importance on a project by project basis. Weighing the various factors requires a documented process for open, informed decision making. While any pavement type may be acceptable, this process provides fact-based reasoning for the pavement type selection.

Changes in the Pavement Selection Process

Several changes in the pavement selection process have been instituted to improve the process, provide more consistency, provide better documentation, and result in more fact-based decisions. Significant changes are as follows:

• Life-cycle cost analysis (LCCA) performed by Office of Pavement Engineering (OPE);

• Unit prices determined by Office of Estimating (OoE); • Added engineering and administrative costs on future maintenance projects; • Added maintenance of traffic costs on future maintenance projects; • Included industry involvement prior to the final selection; • Eliminated Discount Rate Sensitivity Analysis in favor of a single discount rate

provided annually by the federal Office of Management and Budget; and • Developed scoring system to select one alternative.

The New Pavement Selection Process

The new process provides a holistic approach to pavement type selection. This process depends on open and honest communication among various ODOT Divisions and Offices. To improve consistency, most of the work is performed by OPE. Increased attention to subgrade conditions is achieved by early involvement of the Office of Geotechnical Engineering (OGE) in the design process. The process includes industry involvement to allow time to identify any project specific concerns prior to the final decision.

In short, the process works as follows: the Office of Systems Analysis Planning (OSAP) identifies the projects, OGE provides subgrade recommendations, OPE designs the alternatives and prepares the LCCA and pavement selection package, OoE provides unit prices, District develops conceptual maintenance of traffic, OPE scores the alternatives

APPENDIX A

A-3

and informs District and industries, and the PSC selects the approved alternative. The actual selection of the alternatives is based on a scoring system which encompasses many factors including construction and maintenance costs, user impact, constructability issues, and environmental factors.

Pavement Selection Steps

1. OSAP identifies projects as potential major rehabilitation candidates. Also, new pavement alignments identified.

2. OPE organizes a meeting with the District, Priority System Manager, and OGE to determine the critical path time line, date for delivery of soils recommendation and other issues as needed.

3. OPE schedules and performs Dynaflect testing and coring, and researches the pavement history.

4. OPE performs field review with the District and Priority System Manager to discuss potential alternatives, determine which alternatives are feasible, review the existing conditions, and determine the preliminary scope. At this time it may be determined that some projects do not require major rehabilitation and they will become minor rehabilitation.

5. Upon receipt of the soils recommendation, OPE designs the rehabilitation alternatives.

6. OPE calculates LCCA quantities and initial and future user delay. Alternatives such as rubblize or unbonded concrete overlay that require more than 40% removal and replacement due to bridge clearances, etc., will be eliminated from the analysis. The 40% figure was selected by the PSC as the amount beyond which alternatives will not be considered. Below that amount, economics and the scoring system will judge the worthiness of the alternative.

7. OoE provides unit prices. District provides documentation of any maintenance of traffic differences.

8. OPE calculates LCCA, prepares selection package and score, and distributes to District and industries.

9. OPE corrects any errors, submits LCCA package and scoring, and any District or industry comments to PSC.

10. PSC meets and selects the approved alternative. Pavement Selection the ODOT Way - 4-17-03 Page 3 of 10

11. OPE notifies District, FHWA, and industry of the approved alternative and maintains a file of the selection documents.

APPENDIX A

A-4

Roles and Responsibilities

OPE Coordinate with OSAP

Coordinate with District

Coordinate with OGE

Perform Dynaflect testing

Perform coring

Research pavement history and determine the existing buildup

Perform traffic loading predictions

Design pavement alternatives

Calculate LCCA initial construction quantities for all alternatives

Select future maintenance schedule for all alternatives

Calculate LCCA future maintenance quantities for all alternatives

Perform LCCA calculations

Calculate initial and future lane closure days

Score the alternatives

OSAP Supply list of potential major rehabilitation candidate projects

Revise list based on feedback or changes from OPE and District

OGE Coordinate with OPE

Coordinate with District

Perform subgrade investigation

Analyze subsurface investigation

Provide subgrade CBR recommendation

Provide stabilization and undercut recommendations

Determine feasibility of alternatives based on subgrade conditions

OoE Determine unit prices for all items

APPENDIX A

A-5

District Coordinate with OPE

Coordinate with OGE

Supply OPE with needed information

Develop conceptual maintenance of traffic for each alternative and define advantages or disadvantages to each

PSC Review the pavement selection scoring

Select approved alternative

Unit Price Determination

Unit prices will be estimated by the Office of Estimating in accordance with their business rules.

Future Maintenance Schedules

The new process has defined future maintenance schedules for the different pavement types. There are both advantages and disadvantages to this approach. The main advantage is that this removes another variable and a potential area for conflict. The disadvantages are that it does not account for local differences in performance and the schedules may not always be revised quickly to respond to changes in performance, materials, etc.

The schedules are divided by traffic levels. Interstate and other high traffic routes receive more maintenance than low traffic routes. On all future maintenance, once the pavement costs are calculated, they will be increased by an additional 7% to account for the Department’s engineering and administrative costs. Also, the pavement costs will be increased by 10% to account for maintenance of traffic costs. The future maintenance schedules are as follows:

I. Interstates (all), Non-interstate routes with greater than 35 million rigid ESAL’s in the 20- year design period or greater than 30,000 ADT in the most recent Traffic Survey Report from the Office of Technical Services.

A. Flexible, Rubblize, and Crack and Seat Pavements:

1. Year 12: 1.5" overlay with planing (full width of mainline and shoulders);

2. Year 22: 3.25" overlay with planing (full width of mainline and shoulders) and with 1% patching planed surface (percent of planed area); and

3. Year 34: 1.5" overlay with planing (full width of mainline and shoulders).

APPENDIX A

A-6

B. Rigid, Unbonded Concrete Overlay and Whitetopping Pavements:

1. Year 22: Diamond grinding (mainline plus one foot of shoulder), full depth repair 4% of mainline surface area; and

2. Year 32: 3.25" asphalt overlay, full depth repair 2% of mainline surface area.

II. Non-interstate routes with less than 35 million rigid ESAL’s in the 20-year design period and less than 30,000 ADT in the most recent Traffic Survey Report from the Office of Technical Services.

A. Flexible, Rubblize, and Crack and Seat Pavements:

1. Year 14: 1.5" overlay with planing (mainline only); and

2. Year 25: 3.25" overlay with planing (full width of mainline and shoulders) and with 1% patching planed surface (percent of planed area).

B. Rigid, Unbonded Concrete Overlay and Whitetopping Pavements:

1. Year 25: Diamond grinding (mainline plus one foot of shoulder) and full depth repair 4% of mainline surface area.

Pavement Selection Scoring System

A scoring system was developed to weigh and combine all the factors important to pavement type selection. This approach is expected to provide for a more criteria-based pavement type selection.

The scoring system includes many factors. The four major categories are: Cost, User Delay, Constructability, and Environment. A weighting factor is applied to each of the scoring items to differentiate them from one another. This allows the importance factor, discussed later, to be judged independent of how it affects the final score. Initial Construction Cost receives a weight of 40, Future Maintenance Cost receives a weight of 25, all User Delay items receives a weight of 30, all Constructability items receives a weight of 20, and all Environment items receives a weight of 10. The four major categories are further broken down into individual sub-categories where the actual scores are applied.

There are four parts to the score for each factor. Part one is the weighting factor, 40, 25, 30, etc., discussed above. The second part is an importance factor. The importance factor is the relative importance of the item to ODOT. It is to be expected that other entities would assign different levels of importance but as the pavement selection decision belongs to ODOT, so does determining the importance factors. Importance factors vary between one and ten. The third part is a reliability factor. The reliability factor is the accuracy of or confidence in the data. For example, initial cost data is well established and has a high reliability factor but since future maintenance of traffic techniques are

APPENDIX A

A-7

unknown, the reliability of future user delay is low. Reliability factors vary between one and five. The final part is a spread factor. The spread factor accounts for the differences between the alternatives. Spread factors vary between 0 and 1.0 depending on the difference between the alternatives. All of the factors, their weight, importance, and reliability are given below. Spread factors are detailed later.

1. Cost

a. Initial Construction, Weight = 40, Importance (I) = 8, Reliability (R) = 5 b. Future Maintenance, Weight = 25, I = 8, R = 2

2. User Delay (Weight = 30)

a. Initial Construction, I = 3*, R = 3 b. Future Maintenance, I = 6, R = 2

3. Constructability (Weight = 20)

a. Subgrade, I = 7, R = 3 b. Drainage Concerns, I = 2, R = 4 c. Uniformity of Cross-Section, I = 6, R = 5 d. Maintenance of Traffic, I = 7, R = 3

4. Environment (Weight = 10)

a. Recycle-ability, I = 3, R = 4 b. Ride, I = 5, R = 3

* User Delay - Initial Construction is given a low importance rating because it is expected that the same number of lanes as currently exist will be maintained during the initial construction in accordance with ODOT policy 516-003(P). Since the number of lanes is not reduced, the importance is judged to be low.

Definitions

1.a. Cost - Initial Construction

Cost of initial construction for each alternative. Initial construction cost is not affected by discount rate. Lower initial cost is preferable.

1.b. Cost - Future Maintenance

Total cost to maintain the pavement for the entire 35-year analysis period, using the real discount rate for 30-year or greater programs published in the current revision of Circular A-94, Appendix C from the federal Office of Management and Budget. Lower future maintenance cost is preferable.

APPENDIX A

A-8

2.a. User Delay - Initial Construction

Time in lane closure days to complete initial construction of the pavement items. Less time is preferable, however, time to construct the pavement may not be the controlling factor. This factor will not be used for pavements built in new locations or when it is determined that bridge or other work is the controlling factor.

2.b. User Delay - Future Maintenance

Time in lane closure days to complete all of the future maintenance activities. Less time is preferable.

3.a. Constructability - Subgrade

Potential risk due to unanticipated subgrade problems during initial construction. Higher risk could result in higher costs for initial construction due to change orders or could result in reduced performance if problems are not identified and corrected. Various alternatives and their level of risk are as follows:

Unbonded Concrete Overlay No risk

Whitetopping No risk

Rubblize and Roll High risk

New Flexible Pavement Medium to high risk

New Concrete Pavement Medium to high risk

New Composite Pavement Medium to high risk

Lower risk is preferable.

3.b. Constructability - Drainage Concerns

This relates to the ability to provide drainage. When the existing pavement is removed, a new drainage system can be properly located and easily installed. If the existing pavement is left in place, retrofitting new underdrains or replacing outlets of the existing drains is more difficult, may not be properly located, can undermine the existing pavement if the underdrain trench collapses, and may not provide the same level of drainage a new system would. New drainage is preferable to retrofitting.

3.c. Constructability - Uniformity of Cross-Section

Alternatives that do not include removing the existing pavement usually result in a large elevation increase and may require pavement removal and undercutting to lower the elevation at bridges. The result is non-uniform typical section along the

APPENDIX A

A-9

length of the project. Also, if a new lane is being added, there will be non-uniformity across the width unless the existing pavement is removed. Non-uniform sections can result in differential performance. The entire pavement may have to be treated because a part of it is distressed. Uniformity across the length and width of the project is preferable.

3.d. Constructability - Maintenance of Traffic

This relates to the cost and ability to maintain traffic during the initial construction. District must develop a conceptual maintenance of traffic plan for each alternative and define the differences between alternatives. Alternatives with cheaper and/or easier maintenance of traffic are preferable.

4.a. Environment - Recycle-ability

This concerns the future recycle-ability of the pavement to be constructed. There are environmental and performance concerns with using recycled concrete in many applications. Disposal of old concrete may be expensive if no locations exist within the right of way to bury it. Recycled asphalt has none of these concerns when used according to the specifications. The ability to recycle is preferable.

4.b. Environment - Ride

A smooth ride is one of the most noticeable and important factors affecting the traveling public. Pavements built smoother initially tend to maintain smoothness longer. Smoother pavement is preferable.

Spread Factor

The spread factor accounts for the differences between the alternatives. Spread factors vary between 0 and 1.0 depending on the difference between the alternatives.

Initial Construction Cost

Alternatives within the specified percentage of the alternative with the lowest initial cost are assigned the given spread factor. Lowest cost alternative always receives 1.0.

0-3% 3.01-6% 6.01-10% 10.01-15% >15% 1.0 0.8 0.5 0.3 0

Future Maintenance Cost

Alternatives within the specified percentage of the alternative with the lowest future maintenance cost at the real discount rate for 30-year programs published in the most recent federal Office of Management and Budget Circular A-94

APPENDIX A

A-10

Appendix C (3.2% as of Jan. 2003) are assigned the given spread factor. Lowest cost alternative always receives 1.0.

0-10% 10.01-20% 20.01-30% 30.01-40% >40% 1.0 0.8 0.5 0.3 0

User Delay - Initial Construction

Alternatives within the specified percentage of the alternative with the fewest number of days of lane closure for initial construction are assigned the given spread factor. Alternative with fewest days always receives 1.0.

0-25% 25.01-50% 50.01-75% 75.01-100% >100% 1.0 0.8 0.5 0.3 0

User Delay - Future Maintenance

Alternatives within the specified percentage of the alternative with the fewest number of days of lane closure for future maintenance are assigned the given spread factor. Alternative with fewest days always receives 1.0.

0-25% 25.01-50% 50.01-75% 75.01-100% >100% 1.0 0.8 0.5 0.3 0

Subgrade

Unbonded Concrete Overlay and Whitetopping = 1.0

New pavement and pavement replacement, all types = 0.7

Rubblize and Roll, and Crack and Seat = 0.6

Drainage Concerns


Unbonded Concrete Overlay, Whitetopping, Rubblize and Roll, and Crack and Seat = 0.8

Uniformity of Cross Section

If no widening (permanent lane addition), all alternatives = 1.0

If widening:


Rubblize and Roll = 0.8

APPENDIX A

A-11

Unbonded Concrete Overlay, Whitetopping, and Crack and Seat = 0.6

Maintenance of Traffic

Alternatives with an advantage = 1.0

Alternatives with a disadvantage = 0.5

When no alternative has any advantage, all alternatives = 1.0

Recycle-ability

New Flexible and Flexible Replacement = 1.0

Rubblize and Roll = 0.9

Crack and Seat = 0.8

New Rigid, Rigid Replacement, and Whitetopping = 0.7

Unbonded Concrete Overlay = 0.3

Ride

All asphalt alternatives = 1.0

All concrete alternatives = 0.7

The table below shows each factor, its weight, importance, reliability, and the possible spread values.

Factor Weight Importance Reliability Spread Initial Const. Cost 40 8 5 1 0.8 0.5 0.3 0 Future Maint. Cost 25 8 2 1 0.8 0.5 0.3 0 User Delay - Initial Construction 0 3 3 1 0.8 0.5 0.3 0 User Delay - Future Maintenance 30 6 2 1 0.8 0.5 0.3 0 Subgrade 20 7 3 1 0.7 0.6 Drainage 20 2 4 1 0.8 Uniformity of Cross Section 20 6 5 1 0.8 0.6 Maintenance of Traffic 20 7 3 1 0.5 Recycle-ability 10 3 4 1 0.9 0.8 0.7 0.3 Ride 10 5 3 1 0.7

APPENDIX A

A-12

Other factors considered for the scoring system include: force account work, snow and ice differences, late season paving, highway lighting, and pavement markings. These factors were discarded because of low importance, low reliability or both, lack of any defensible spread difference between alternatives, or current research in the area. For example, highway lighting is designed the same for all pavement types so there is no difference between alternatives.

The score for each factor is determined by multiplying the weight by the importance by the reliability by the spread. For example, the alternative with the lowest initial construction cost would get a score for initial construction cost of 40*8*5*1.0 = 1600. The total score for each alternative is the sum of the individual scores for each factor. The total number of points available is 4500.

Future Updates to the Pavement Selection Process

It is expected that this process will be revised and updated in the future. A documented process will be developed to consider and implement or reject any changes which will affect pavement type selection. This will include design changes, specification changes, changes to the future maintenance schedules, changes to the scoring system, and all supporting information such as rules for estimating unit prices, production rates for lane delay, etc.

Summary

The new process provides a more holistic approach to pavement selection. It is intended to account for all of the important differences between different pavement types and rehabilitation treatments. Each step in the process is clearly documented and the responsibilities are clearly defined. The process is not intended nor expected to make everyone happy. In a competitive environment between two industries, there will always be a winner and a loser on each project. This process will clearly show why one alternative was selected since decisions are made on technical criteria. The new process is an improvement and provides ODOT with a valuable tool to select the proper pavement type for a long-life, quality pavement.

Appendix B

Pavement Type Selection Flow Charts

for

10 Comparison States

APPENDIX B

B-1

Sta

rt

Spe

cial

Des

ign?

(Not

e)S

ubm

it to

des

ign

New

Con

st./

Rec

onst

.

Des

ign

HM

A &

PC

CPe

rform

Life

-cyc

leco

st a

naly

sis

Life

-cyc

le c

ost

Diff

eren

ce>1

0%

Sel

ect p

avem

ent

type

and

des

ign

base

d on

low

est

life

cycl

e co

st

Type

and

des

ign

sele

cted

by

pave

men

tse

lect

ion

com

mitt

e

Wid

enin

g>6

'

Shor

t Seg

men

t

Bene

ficia

l to

mat

ch e

xist

ing

pave

men

t ?

Wid

enin

g w

ithre

surfa

cing

Pav

emen

tw

iden

ing

>4'

Des

ign

JPC

P, F

ull

dept

h A

C

Des

ign

full-

dept

hA

C &

com

posi

tepa

vem

ent

Res

trict

ions

dict

ate

PC

Cba

se

Use

PC

C B

ase

9"th

ick

Base

type

cont

ract

ors

optio

nU

se B

itum

inou

sba

se 9

" Thi

ck

Perfo

rm 1

st c

ost

anal

ysis

and

sel

ect

type

and

des

ign

base

d on

1st c

ost

Spe

cify

Bas

e to

Mat

ch e

xist

ing

pave

men

t

No

No

Yes

Yes

No

Yes

Yes

Yes

Yes

No

No

No

Yes

Yes

No

No

Yes

No

Spec

ial D

esig

n N

ote

Incl

udes

;H

igh

stre

ss in

ters

ectio

nsU

se o

f JR

CP

to m

atch

exi

stin

g pa

vem

ent

Use

of C

RC

P to

mat

ch e

xist

ing

pave

men

tD

esig

ns to

acc

omm

odat

e he

avily

load

ed v

ehic

les

ILLI

NO

IS D

EP

AR

TME

NT

OF

TRA

NS

PO

RTA

TIO

NP

AV

EM

EN

T TY

PE

SE

LEC

TIO

N P

RO

CE

SS

APPENDIX B

B-2

Subjectively Considerother factors such as:

Scope of ProjectAdjoining pavement

ConstructabilityTraffic ControlCompetition

Make Type Selection

SelectionDocument

Issued

INDIANA DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS

(Current)



estimate

Yes


APPENDIX B

B-3

Perform SubjectiveEngineering Analysis

Alternative SatisfiesEngineering

Criteria


Make Type Selection

SelectionDocument

Issued

MARYLAND DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS

(Existing)

Yes



estimate

Yes


APPENDIX B

B-4

Perform ObjectiveEngineering Analysis

Use weights andnumerical criteria forthe various non-cost

related factors

Alternative Scores the mostpoints


Make Type Selection

SelectionDocument

Issued

MARYLAND DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS

(Future)

Yes



estimate

Yes


APPENDIX B

B-5

MICHIGAN DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS

Develop PreliminaryDesignsAt Least1 Rigid

1 Flexible





Cycle Cost


APPENDIX B

B-6

TrafficBESAL’s

>10,000,000

TrafficBESAL’s7,000,000

to10,000,000

Rigid PavementSelected


TrafficBESAL,s1,000,000

to7,000,000

TrafficBESAL’s

<1,000,000

Subgrade SoilR-Value

>40

Flexible PavementSelected


Select PavementType with LowestLife Cycle Cost

Subgrade SoilR-Value

>40

Flexible PavementSelected



Yes

No

Yes

No


Yes Yes

No

Yes Yes

No

MINNESOTA DEPARTMENT OF TRANSPORTATIONPAVEMENT TYPE SELECTION PROCESS

APPENDIX B

B-7


Alternative Satisfies Engineering

Criteria

Develop PreliminaryDesigns




Yes

NEW YORK DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS



Cycle Cost


APPENDIX B

B-8


AlternativeSatisfies Engineering

Criteria

Develop Preliminary DesignsNew or Reconstruction, at least 2

(1 rigid and 1 flexible)Rehabilitation, at least 3



Committee


SelectionDocument

Issued


Yes

PROVINCE OF ONTARIOPAVEMENT TYPE SELECTION


Cycle Cost

No

Yes

No

Project Length > 10 Lane km and ESAL’s > 1,000,000within next 4 to 5 years

Detailed Design PlusDevelopment of LCCA

Cost AdjustmentFactors for

Flexible/RigidAlternative Bid


Committee

Alternate Bidding1 rigid Design

1 Flexible Design

Yes

EliminateAlternative

APPENDIX B

B-9

Prepare pavementdesigns

Construction CostsAre they > $10M

($1 M for interstates)?

LCCA not requiredDistrict determines

pavement type

Perform LCCA DeterminePresent Worth

Isdifference in costs

< 10%

Select alternativewith the lowestpresent worth

Options are consideredequal value to DOT;District determines

pavement type

Can LCCA bewaived on special

considerations

LCCA Required

Committee reviewDistrict makes pavement

type selection

SelectionDocumentPrepared

District determines equivalent sections(minimum of 2; ACP and PCCP): Field view committee

No Yes

Yes No

No Yes

PENNSYLVANIA DEPARTMENT OF TRANSPORTATIONPAVEMENT TYPE SELECTION PROCESS

APPENDIX B

B-10



Criteria


Pavement TypeSelection CommitteeConcurs in Selection

SelectionDocument

Issued

Results of theEngineering; LCCA; and

Environmental,Operational, and Societal

Factors Analysis areReviewed and type

Selection Made

Yes

Reanalyze

No

No

WASHINGTON STATE DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS

(Existing)

Yes



estimate

JustificationRequired for

FurtherConsideration

Alternativecan be Justified in

spite of cost

Yes

No


No

Yes

APPENDIX B

B-11



Criteria

EvaluateEnvironmental,

Operational, andSocietal Factors


Meets Criteria EliminateAlternative

Pavement TypeSelection CommitteeConcurs in Selection

SelectionDocument

Issued

Results of theEngineering; LCCA; and

Environmental,Operational, and Societal

Factors Analysis areReviewed and type

Selection Made

Yes

Reanalyze

No

No

WASHINGTON STATE DEPARTMENT OF TRANSPORTATIONTYPE SELECTION PROCESS

(Proposed revision)



estimate

No

JustificationRequired for

FurtherConsideration

Alternativecan be Justified in

spite of cost

Yes

Yes

No


No

APPENDIX B

B-12

1972 AASHTO Design Guide (WisPave AC & PCC Modules)(Inputs: soils, traffic, serviceability, mix parameters, etc.)

Determine Equivalent Sections(generally 2, but up to 8)

Determine SN

LCCA (WisPave LCCA Module)5% discount rate, 50-year analysis period

Performance Inputs(hard-coded service lives)

Initial StructureRehabs

Agency Cost Inputs(using WisPrice or other)Construction unit costs

Rehab unit costsMaint costs ($/lane mi)

Deterministic LCCA Results

CostDifference

>5%

Peer Review CommitteeDetermines Pavement

type

SelectedPavement

Type

SelectedPavement

Type

Select Low CostAlternative Yes No

WISCONSIN DEPARTMENT OF TRANSPORTATIONPAVEMENT TYPE SELECTION PROCESS

Appendix C

Completed Questionnaires

for the

Comparison States

Appendix C - Illinois

C-1

Purpose The purpose of this interview is to gain insight into the following Illinois Department of Transportation practices:

• Pavement type selection • Engineer’s estimate and life cycle cost analysis • Other items that affect cost

Agency Interviewed Illinois Department of Transportation I26 East Ash Street Springfield, IL 62704-4792 Interview conducted between 10:00 AM and 12:30 PM on October 22, 2003. Person(s) Interviewed

Name Title Phone Email David L. Lippert, P.E.

Engineer of Physical Research 217/782-7200 217/782-2572

[email protected]

Priscilla Tobias, P.E. David L. Piper, P.E.

Policy Engineer Highway Policy Engineer

217/524-1649 217/785-0720

[email protected] [email protected]

Matt Mueller, P.E. Technical Services Engineer 217/782-3479 [email protected]

1. Do you have a documented pavement type selection procedure for:

New Construction – Yes Reconstruction – Yes Rehabilitation – Yes (if the job is widening, the policy advises that selection be based on first cost.)

Special designs are not covered by policy. These include rubblization and unbonded concrete overlays, “high stress” locations, high traffic with traffic factor exceeding 35), etc. LCCA is not used for these situations. Page 54-1(9), Figure 54-1A of Pavement Design manual covers this procedure.

2. How long have you used the current type selection procedure? A procedure has been in place since mid 70s. Mechanistic-empirical (M-E) based design was adopted in 1989 by IDOT after 8 years of research and development. IDOT subjected the M-E procedures to field verifications and internal review prior to implementation. Issues ranging from design parameters and their effect on pavement design, to life cycle cost selection, were analyzed. An IDOT-Industry task force was set up to provide a forum for industry input during


C-2

the decision-making process. Based on these activities, IDOT adopted and implemented the new pavement design procedures and associated type selection processes in 1990. These continue to serve IDOT to this day. 3. Changes made over the last 5 years: The procedure has been “tweaked” slightly over the 5 years. Recently, the need to provide sealing of transverse joints in jointed concrete pavements has been eliminated. More changes are underway at this point, however, nothing has been made official as yet.

What prompted the change? Changes to design details (e.g., joint details such as saw cuts, dowel design, etc) prompted the minor “tweaks” to this point.

4. Have you used alternative bidding as a means of making a pavement type selection

during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval?

No. IDOT does not use alternative bidding. 5. Importance and extent of industry involvement in the development of type selection

process? An IDOT-Industry task force was set up to facilitate industry input into the pavement type selection process during its development (see question 2 for details). Based on the industry review, IDOT re-evaluated and refined its design and type selection process. However, industry has no involvement in the way projects are selected within IDOT’s pavement type selection process. 6. How was the selection process implemented within the agency? The selection process is implement through a design manual. Districts perform the design and economic analyses of alternatives using the established unit costs and scheduled maintenance and rehabilitation and routine maintenance quantities and forward the results to the central bureau. The central bureau reviews the designs and economic analyses for accuracy. For new construction or reconstruction, if the LCCA leads to a cost difference of greater that 10 percent for competing alternatives, the alternative with the lowest cost is chosen. If the costs are within 10 percent of each other, then the districts refer the design to the Pavement Selection Committee for final decisions. The Committee comprises of 5 voting members – 3 central bureau members and 2 members where the project is located. The committee evaluates several “secondary” factors subjectively before arriving at a decision. These include:

• Construction considerations (e.g., staging, shallow utilities) • Adjacent pavements (commonality, urban centers, signals, stop-go traffic, etc) • District’s local issues (past performance, impact on business due to construction, etc) • First cost • Project size and scope


C-3

7. How is the type selection process related to the overall project selection, budgeting,

planning process used by the agency? The type selection process is secondary to the overall programming of the DOT’s capital outlay process. Programming is done years in advance and type selection is performed months (in some cases years) in advance of actual letting of jobs. Pavement type selection is done in Phase I and provides a more realistic estimate of costs. 8. Pavement types used for new construction or reconstruction over the last 5 years

(guesstimate)

Approximate sq. yd. (do not track lane miles)

Pavement Type

Interstate Other 4 lane

Performance (Good Fair Poor)

Full depth ACP 3,139,851 Good Deep Strgth ACP N/A N/A ACP(less than 6”) agg base

N/A N/A

Jointed Plain (JPCP) 4,577,865 Good Jointed Reinforced (JRCP)

26038 N/A – Insufficient data since only small quantities built for compatibility with adjacent sections.

Continuously Reinf. (CRCP)

2,062,318 Good

*The last five years saw an unusual amount of interstate pavement being rehabilitated or reconstructed, which explains the high numbers for concrete.

9. Thickness design procedure used and design life

ACP (Full-depth AC) – M-E procedure (for new construction and reconstruction PCCP (JPCP) – M-E procedure for new construction and reconstruction PCCP (CRCP) – does not go through LCCA (special design); use modified AASHTO.

Widening jobs treated as special design. If widening is > 6’ and involves resurfacing, modified AASHTO used for flexible and composite pavements.

10. What analysis period used for each pavement type? For JPCP and full-depth AC, a 40-year life cycle capturing at least 1 rehabilitation is used. 11. Are there different foundation/base requirements for AC and PCC? No. Both are treated similarly. A minimum of 12” improved subgrade (pozzolonically modified (most often lime-treated or granular backfill) is required to serve as an adequate working platform. This layer is not given structural credit and is not considered in cost analysis. Generally, JPCP requires as stabilized base and CRCP a bituminous stabilized base.


C-4

12. Do you use smoothness as criteria and if yes, do you use the same initial serviceability in design?

Smoothness is not used as a design criterion. It is only used as a construction specification. 13. Typical costs and method of contract measurement (e.g., last year’s average bid price)

ACP in place $37/sy; Avg Thk = 14” JPCP (slab only) $34/sy; Avg Thk = 10” JRCP (slab only) N/A – Insufficient sample CRCP (slab only) $30 to $44/sy (price based on completion schedule – accelerated completion costs more; Avg thk = 13 to 14”

Note that the CRCP design is not equivalent to other designs since it is typically considered only if heavy traffic is present (TF > 35). 14. How important is first cost versus future costs? First cost, routine maintenance (paint markings, reflectors, lane markers, etc.), and maintenance and rehabilitation costs are all considered. There is not weighting attached to these categories in the LCCA process. All the dollar amounts are considered and reduced to present worth in LCCA. First cost is discussed in the committee as a secondary factor when two alternate designs are within 10 percent of each other. It is possible that sometimes, this may drive decisions when the costs are very close. 15. Is life cycle cost analysis used? Yes 16. Analysis period 40-year life cycle that ensures that at least 1 major rehab is covered. 17. Discount Rate (how established) Department hired an economist in 1988 who reviewed the information present and established a rate of 3% for all public work. Prior to that Interest rate and Inflation rate were used. 18. Initial Costs – Estimating procedure Quantity, material costs, and production costs enter the initial cost determination. Districts estimate costs and central bureau reviews them.


C-5

19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated.

There is a Statewide database of unit costs which are frequently updated. The Central office estimating engineer keeps a meticulous record of all the costs on unit cost worksheets and maintains a running total. 20. Are price adjustment factors used for any materials, and if so are they used in the life

cycle cost analysis. No. 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) No ongoing process of active comparison. Actual costs versus estimated costs could differ based on market forces which are current to the time of letting, however, this does not affect type selection. Estimates are done sometimes years in advance. Projects are evaluated if there are overruns but not all projects are evaluated for overruns. 22. Routine maintenance (how estimated, operations included) Routine maintenance as defined by IDOT refers to paint markings, lane markings, etc., which are common to both full-depth HMA and JPCP pavements. These quantities are assigned a fixed yearly value in the maintenance and rehabilitation schedule based on experience. Other maintenance activities such as crack sealing, patching, etc., are directly considered in the maintenance and rehabilitation schedule. The schedule specifies that certain maintenance activities be done at fixed time intervals based on IDOT experience. These are applied in the LCCA process. The unit costs for these activities are updated annually and are a function of pavement type, location, and highway class.


C-6

Engineering and Construction Considerations Note that all the factors listed below are secondary factors which will be considered by the Pavement Type Selection Committee only if the LCCA for the two design alternatives yields a difference of less than 10 percent.

Factor C P I Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage)

2. Highway functional class

3. Traffic Considered prior to LCCA being performed – in the design phase.

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc)

5. Construction considerations

a. Staging

b. Clearance for equipment

c. Construction operations

d. Traffic operations during construction

e. Construction seasons

6. Consideration of future maintenance operations (maintenance of traffic, ease of maintenance)

7. Performance of similar pavements in the area

8. Availability of local materials, contractor’s capabilities, and experienced agency personnel.

9. Pavement Continuity

a. Adjacent sections

b. Adjacent lanes

10. Noise issues

11. Subgrade soils

12. Climate

13. District or local preference

14. Ease of maintenance

15. Recycling Indirectly accounted for in the LCCA – unit prices reflect the used of recycled materials.

16. Conservation of materials and energy Indirectly accounted for in the LCCA – unit prices reflect the used of recycled materials.

17. Stimulation of Competition 18. Safety considerations (rutting, friction, lighting, etc) Addressed in specifications/maintenance rehabilitation schedule.

19. Smoothness Addressed in specifications. C = considered; P = primary or secondary choice; I = importance (on a scale from 1 to 5)


C-7

23. Rehabilitation (how is timing estimated, techniques used, etc.) Major rehabilitation activities such as overlays for full-depth AC pavements and CPR for JPCP are specified in the maintenance and rehabilitation schedule based on experience. The costs for these quantities are determined based on the cost worksheets maintained by IDOT.

Salvage Value (remaining life) – Not considered since it is assumed that life cycle is long enough. Residual value (recycling) – Indirectly considered in unit cost sheets. Construction traffic control (crossovers, added lanes, barriers, detours, etc.) – Secondary factor in type selection process. Engineering and administration – Not considered.

24. How are users costs weighted in relation to agency costs? N/A. User costs are not considered in LCCA. 25. Vehicle operating costs Not considered. 26. User Delay Not considered. 27. Description of the analysis process N/A 28. Routine maintenance IDOT definition differs from common perception. Definition could be revised. For full-depth AC and JPCP it includes lane striping, delineators, lane markets, etc. 29. Preventive maintenance Preventive maintenance concepts are not used by IDOT at the present time. 30. What are the state’s standard routine and preventive maintenance operation

and schedule by pavement type? As defined in Question 29, Routine maintenance is assigned a fixed cost which does not vary by pavement type. “Other” maintenance activities such as crack sealing, patching, etc., are provided in the schedules in the Pavement Design Manuals.


C-8

31. Allocation of resources between maintenance, rehab, new and reconstruction IDOT operates on the principle of maintaining the existing system at optimum conditions. Adequate resources are allocated in each category to meet this goal. 32. Do you have a formal system to track pavement condition, cost, and

survivability? There is a system to track pavement condition (condition rating system -- CRS) and survivability. There is no system to track costs and there is no “formal” pavement management system. IDOT performs a routine review of CRS and assesses needs. 33. Do you allow old concrete to be recycled? If so into what products? Percentage

limits? Yes. Recycled concrete is used in concrete, as subbase layer, as capping layer for working platform, in fills/embankments, as well as in shoulders. 34. Do you allow HMA materials to be recycled? If so into what products?

Percentage limits? Yes. RAP is used in binder courses, shoulders, capping layers for working platform.

Appendix C - Indiana

C-9

Purpose The purpose of this interview is to gain insight into the following Indiana Department of Transportation practices:


Agency Interviewed Indiana Department of Transportation 120 S. Shortridge Road Indianapolis, IN 46219 Person(s) Interviewed

Name Title Phone Email Dave Andrewski Pavement Design Engineer 317-610-7251 [email protected] Kumar Dave Pavement Design Engineer 317-610-7251


New Construction – In design Manual Reconstruction – In design Manual Rehabilitation

2. How long have you used the current type selection procedure? At least 10 years 3. Changes made over the last 5 years: Nothing significant 4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? No 5. Importance and extent of industry involvement in the development of type selection process? Try to maintain an open relationship with both industries


C-10

6. How was the selection process implemented within the agency? Included in the design manual 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? Not directly related. Selection process occurs after a determination is made to proceed with the project. 8. Pavement types used for new construction or reconstruction over the last 5 years

Approximate lane miles Pavement Type Interstate Other 4 lane


Full depth ACP Deep Strgth ACP * Good ACP (less than 6”) agg base

Jointed Plain (JPCP) * Good Jointed Reinforced (JRCP)


* Data not available from the State on miles of paving by type each year. However, subsequent conversations with industry reps indicated about 20 to 30 percent of the high reconstruction go to PCC each year. 9. Thickness design procedure used and design life (if AASHTO which version)

ACP AASHTO - DARWIN PCCP AASHTO - DARWIN

10. What design period used for each pavement type?

Flexible – 20 years Rigid – 30 years

11. Are there different foundation/base requirements for AC and PCC? No 12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Have ride specifications for both pavement types. Currently not the same but they are moving towards that goal. Use same initial serviceability.


C-11

13. Typical costs and method of contract measurement

ACP in place $/_______42_______/ton sy cy other JPCP (slab only) $/____10” 26.68, 11” 28.25____sy cy other JRCP (slab only) $/_____________sy cy other CRCP (slab only) $/_____________sy cy other

14. How important is first cost versus future costs? First cost is one of the subjective factors considered 15. Is life cycle cost analysis used? Yes - State currently has a research project underway at Purdue to improve the process 16. Analysis period 40 years 17. Discount Rate (how established) For general purposes a 4% discount rate can be assumed. However, it is recommended that a range of rates between 0% and 10% be evaluated. 18. Initial Costs – Estimating procedure Use recent unit costs for project let over the last 1 to 2 years 19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. Look at high and low bids, and then make a best estimate based on project factors. Industry is given the opportunity to provide input on the values used. 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. Not permitted by State law (constitution?) 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) Not considered


C-12

Engineering and Construction Considerations Factors used, scoring system, primary factors secondary factors, weights, importance, etc

Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)

Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) N

2. Highway functional class N 3. Traffic Y 5

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc) Y 5 Yes for white topping and break and seat

5. Construction considerations a. Staging Y 1 b. Clearance for equipment N c. Construction operations N

d. Traffic operations during construction N e. Construction seasons N


C-13

Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)

Comments

6. Consideration of future maintenance operations (maintenance of traffic, ease of maintenance) N

7. Performance of similar pavements in the area N

8. Availability of local materials, contractor’s capabilities, and experienced agency personnel. N

9. Pavement Continuity N a. Adjacent sections N b. Adjacent lanes N

10. Noise issues N Is becoming an issue. State changed tining to address the issue 11. Subgrade soils Y 3 Settlement 12. Climate N 13. District or local preference N 14. Ease of maintenance N 15. Recycling N

16. Conservation of materials and energy N 17. Stimulation of Competition Y Subjectively when cost are equal

18. Safety considerations (rutting, friction, lighting, etc) N 19. Smoothness N


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22. Routine maintenance (how estimated, operations included) Based on maintenance management system, historical data, and pavement management data. 23. Rehabilitation (how is timing estimated, techniques used, etc.) Based on pavement management data

Salvage Value (remaining life) – Consider the residual value of the pavements service life at the end of the analysis period Residual value (recycling) – Not considered Construction traffic control (crossovers, added lanes, barriers, detours, etc.) – Consider only if there is a significant difference between pavement types Engineering and administration – No since similar for both

24. How are users costs weighted in relation to agency costs? User costs will be incorporated when Purdue research is completed 25. Vehicle operating costs 26. User Delay 27. Description of the analysis process In design manual 28. Routine maintenance Reactive operations, pot holes, etc 29. Preventive maintenance Crack and joint sealing, chip seals 30. What are the state’s standard routine and preventive maintenance operation and schedule by pavement type? Crack sealing every 2 to 3 years Chip seal 4 to 6 years Contraction joint sealing 8 to 12 years 31. Allocation of resources between maintenance, rehab, new and reconstruction No formal allocation


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32. Do you have a formal system to track pavement condition, cost, and survivability? Pavement management system 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Becomes property of the contractor Encourage the contractor to use as subgrade strengthening layer. Cap off with granular layer to prevent leaching 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Becomes property of the contractor In HMA up to 25% Up to 15 % use grade of AC specified in contract. 15 to 25% an asphalt modifier is required to soften old asphalt.

Appendix C - Maryland

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Purpose The purpose of this interview is to gain insight into the following Maryland State Highway Administration practices:


Agency Interviewed State Highway Administration, Maryland Department of Transportation 2323 W. Joppa Road Lutherville, MD 21093 Person(s) Interviewed

Name Title Phone Email Tim Smith

Acting Pavement Division Chief

410-321-3110 [email protected]

Jeffrey N. Wthee Transportation Engineer 410-321-3115 [email protected] 1. Do you have a documented pavement type selection procedure for:

New Construction: Not formally, Using interim procedure while further revisions are under development Reconstruction: Not formally, Using interim procedure while further revisions are under development Rehabilitation

2. How long have you used the current type selection procedure? 6 months 3. Changes made over the last 5 years:

Currently being revised. New process expected to be completed and adopted early next year. What prompted the change? Trying to develop a more consistent and objective selection process. Being do to address issues raised by the HMA industry on a major project.


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4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? It was used on one project under experimental project SEP-14. Prices were very good and management is

5. Importance and extent of industry involvement in the development of type selection process? Partnering with Industry and FHWA. Provide review comments.

6. How was the selection process implemented within the agency?

Formal process when adopted will be included in Materials and Technology Manual 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? Assumptions of cost made during the planning stage may impact pavement strategy and/or type.

8. Pavement types used for new construction or reconstruction over the last 5 years



Full depth ACP Deep Strgth ACP X X Good ACP(less than 6”) agg base

Jointed Plain (JPCP) X X* Good Continuously Reinf. (CRCP)

*Only 13 lane miles of new or reconstructed pavements were constructed in the last 5 years and that went PCC

9. Thickness design procedure used and design life (if AASHTO which version)

ACP: AASHTO 93 PCCP: AASHTO 93

10. What design life used for each pavement type?

ACP - 15 years PCCP - 25 years

11. Are there different foundation/base requirements for AC and PCC? Treat subgrade based on site conditions not pavement type.


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12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Same smoothness criteria for both pavement types. Initial serviceability: PCC 4.5 HMA 4.2 13. Typical costs and method of contract measurement

ACP in place $/____36__________/ton sy cy other JPCP (slab only) $/_10” 40____________sy cy other JRCP (slab only) $/_____________sy cy other CRCP (slab only) $/_____________sy cy other

14. How important is first cost versus future costs? Straight LCCA is used with no weighting of initial vs future 15. Is life cycle cost analysis used? Yes – Probabilistic per FHWA 16. Analysis period 40 years 17. Discount Rate (how established) Probabilistic approach is used per FHWA Guidelines. Range of 3% to 5% with a mean of 4%. 18. Initial Costs – Estimating procedure Use last three years of low bid data. Statistically adjust data and throw out outliers. Then the process are broken out by low, medium, and high quantities. For concrete, because of the low number of projects, non-winning alternative bids are used. Also asking industry to supply regional input on prices.


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Engineering and Construction Considerations

Factors used, scoring system, primary factors secondary factors, weights, importance, etc

Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)

Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) Y 1

2. Highway functional class N 3. Traffic Y 3 Land use – impact of materials hauling

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc) N

5. Construction considerations a. Staging Y 3 b. Clearance for equipment N c. Construction operations Y 3

d. Traffic operations during construction Y 4 e. Construction seasons Y 1


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Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)

Comments 6. Consideration of future maintenance operations

(maintenance of traffic, ease of maintenance) Y 1


8. Availability of local materials, contractor’s capabilities, and experienced agency personnel. Y .5

9. Pavement Continuity a. Adjacent sections Y 2 b. Adjacent lanes Y 2

10. Noise issues Y .5 11. Subgrade soils N 12. Climate N 13. District or local preference Y .5 14. Ease of maintenance Y 1 15. Recycling N

16. Conservation of materials and energy N 17. Stimulation of Competition Y/N S

18. Safety considerations (rutting, friction, lighting, etc) Y 2 rutting 19. Smoothness N


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19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. Have just instituted the procedure and plan to update annually. 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. Yes – for liquid asphalt 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) No 22. Routine maintenance (how estimated, operations included) Not used 23. Rehabilitation (how is timing estimated, techniques used, etc.) Pavement management supplies average and standard deviation for different pavement types.

Salvage Value (remaining life): Yes – remaining life at end of the analysis period Residual value (recycling): No Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Yes Engineering and administration: No

24. How are users costs weighted in relation to agency costs? equal 25. Vehicle operating costs No 26. User Delay Yes per FHWA procedure 27. Description of the analysis process 28. Routine maintenance Reactive - potholes, etc.


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29. Preventive maintenance Slurry seals, thin overlays 30. What are the states standard routine and preventive maintenance operation and schedule by pavement type? Preventive maintenance applied occasionally. 31. Allocation of resources between maintenance, rehab, new and reconstruction Nothing formal 32. Do you have a formal system to track pavement condition, cost, and survivability? Yes – pavement management system 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes – but have not removed any in recent years 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Yes -15% surface, 25% base. May increase based on mix design. Above 15 % requires asphalt modifier.

Appendix C - Michigan

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Purpose The purpose of this interview is to gain insight into the following Michigan Department of Transportation practices:


Agency Interviewed Michigan Department of Transportation Construction and Technology 8885 Ricks Road Lansing, MI 48909 Person(s) Interviewed

Name Title Phone Email Curtis Bleech Pavement Engineer 517-322-1237 [email protected] Kevin Kennedy Capital Preventive

Maintenance Engineer


New Construction: Yes Reconstruction: Yes Rehabilitation: Unbonded overlays, break & seat

2. How long have you used the current type selection procedure? 3 years 3. Changes made over the last 5 years: Developed to meet the requirements of State legislation passed in 1979. Public Act 79, states that “the department shall develop and implement a life cycle cost analysis for each project for which total pavement costs exceed one million dollars funded in whole, or in part, with state funds. The department design and award paving projects utilizing material having the lowest life cycle costs.” The legislation also states “life cycle costs shall also compare equivalent designs and shall be based upon Michigan’s actual historic project maintenance, repair and resurfacing schedules and shall include estimates of user costs throughout the entire pavement life.” Note: Because of the wording of the legislation, rehabilitation schedules and costs must be based on the past performance of pavements in Michigan. This does not allow modification based on design improvements. For example, asphalt mixtures are now based on Superpave and PCC


C-24

design has been change from JRCP to JPCP. However, performance must be based on the old designs

What prompted the change? Legislation 4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? Two projects under SEP 14. No additional projects currently planned, but the State hasn’t ruled out future projects. 5. Importance and extent of industry involvement in the development of type selection process? Participated in an ad hoc committee, where consensus on the new procedure was developed. 6. How was the selection process implemented within the agency? Issued in a revised pavement design manual by the Chief Operations Officer 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? It isn’t 8. Pavement types used for new construction or reconstruction over the last 5 years

Pavement Type Approximate lane miles, Interstate & other 4 Lane


Full depth ACP Deep Strgth ACP 5% ACP(less than 6”) agg base

Jointed Plain (JPCP) & JRCP

95%

Jointed Reinforced (JRCP)



ACP: AASHTO 93 PCCP: AASHTO 93


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10. What analysis period used for each pavement type? 20 Years for both types 11. Are there different foundation/base requirements for AC and PCC? Yes – Flexible requires 18-inch sand subbase and 6-inch aggregate base, PCC requires 12-inch sand subbase and 4-inch open-graded base. 12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Yes-Currently based on Ride Quality Index measured with either profilograph or profilometer. Will be going to IRI. 13. Typical costs and method of contract measurement

ACP in place $/25.40 to 45.39/ton sy cy other $28 to $50 metric ton JPCP (slab only) $/10.25” 22.21sy cy other 260mm $26/m2, JRCP (slab only) $/10.25” 27.21_sy cy other 260mm $32.55/m2, CRCP (slab only) $/_____________sy cy other

14. How important is first cost versus future costs? Same importance, evaluated in LCCA 15. Is life cycle cost analysis used? Yes Based on Equivalent Uniform Annual Cost 16. Analysis period Varies depending on the design. 17. Discount Rate (how established) OMB A94


C-26



Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)

Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) NO

2. Highway functional class NO 3. Traffic NO


NO

5. Construction considerations NO

a. Staging NO b. Clearance for equipment NO c. Construction operations NO

d. Traffic operations during construction NO

e. Construction seasons NO


C-27

Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)


(maintenance of traffic, ease of maintenance) NO

7. Performance of similar pavements in the area NO

8. Availability of local materials, contractor’s capabilities,

and experienced agency personnel. NO

9. Pavement Continuity NO

a. Adjacent sections NO b. Adjacent lanes NO

10. Noise issues NO 11. Subgrade soils NO 12. Climate NO 13. District or local preference NO 14. Ease of maintenance NO 15. Recycling NO

16. Conservation of materials and energy NO

17. Stimulation of Competition NO

18. Safety considerations (rutting, friction, lighting, etc) NO

19. Smoothness NO


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18. Initial Costs – Estimating procedure Only costs that differ between alternatives are considered. Include cost items such as mainline pavement, shoulders, joints, subbase, base, underdrains, and traffic control. Unit prices are determined from past MDOT projects and are based on the weighted average of low bid data. 19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. Prices are updated on a semiannual basis based on low bid data from the previous 18 months. They are developed following procedures set forth in the Pavement Design Manual. 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. Not used 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) No 22. Routine maintenance (how estimated, operations included) Not 23. Rehabilitation (how is timing estimated, techniques used, etc.) Based on MDOT maintenance data (contract work only). Historical contract data and pavement condition data for the pavement management system are used to develop maintenance cost schedules.

Salvage Value (remaining life): None – Analysis period goes to the end of life Residual value (recycling): No Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Rehab only. Considered same for initial Engineering and administration: Included in future costs only.

24. How are users costs weighted in relation to agency costs? Not weighted, user delay included n LCCA 25. Vehicle operating costs


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26. User Delay Speed delay and lane closure delay costs are calculated using a University of Michigan program. 27. Description of the analysis process 28. Routine maintenance Reactive 29. Preventive maintenance Contract 30. What are the states standard routine and preventive maintenance operation and schedule by pavement type? Not stated 31. Allocation of resources between maintenance, rehab, new and reconstruction 32. Do you have a formal system to track pavement condition, cost, and survivability? Yes, serves as basis for the rehabilitation schedules. 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes. Contractors become owners and generally do not use in project but rather use it in their private work. The following are the Michigan specifications for recycling of PCC:

902.03 Coarse Aggregates for Portland Cement Concrete. Use Michigan Class 4AA, 6AAA, 6AA, 6A, 17A, and 26A coarse aggregate produced from natural aggregate, iron blast furnace slag, or reverberatory furnace slag sources. Michigan Class 6A, 17A and 26A may be produced by crushing Portland cement concrete, but only for uses stipulated by this specification. The bulk dry specific gravity must be within the limits established by freeze-thaw testing. Aggregates must conform to the grading requirements in Table 902-1, the physical requirements in Table 902-2, and the following. A. Slag Coarse Aggregate. Iron blast furnace slag or reverberatory furnace slag conforming to the grading specified for the concrete mixture must have a dry (loose measure) unit weight of not less than 70 pounds per cubic foot as determined by MTM 123. B. Crushed Concrete Coarse Aggregate. Use only crushed concrete coarse aggregate originating from concrete sources owned by the Department as part of the contracted project. Crushed concrete coarse aggregate may be used in concrete mixtures for curb and gutter, valley gutter, sidewalk, concrete barriers, driveways, temporary pavement, interchange ramps with commercial ADT below 250, and concrete shoulders. Crushed concrete coarse aggregate may not be used in mainline pavements or ramps with commercial ADT equal to or greater than 250, concrete base


C-30

course, bridges, box or slab culverts, head walls, retaining walls, prestressed concrete, or other heavily reinforced concrete. 693 902.03 Process crushed concrete coarse aggregate in a manner that avoids contamination with any non-concrete materials including joint sealants, HMA patching, and base layer aggregate or soil. Contamination particles retained on the-inch sieve are limited to 3.0 percent maximum by particle count of the total aggregate particles. The aggregate stockpile will be rejected totally when there is any evidence of contamination from non-Department sources such as building brick, wood, or plaster. Pieces of steel reinforcement are allowable in the stockpile provided they pass the maximum grading sieve size without hand manipulation. The fine aggregate portion of the gradation must not exceed a liquid limit of 25.0 percent or a plasticity index of 4.0. Crushed concrete coarse aggregate will be tested for freeze-thaw durability for each project. This testing requires a minimum of three months after samples of the produced aggregate are received in the laboratory. Use equipment and methods to crush concrete that will maintain uniformity in aggregate properties: specific gravity �0.05 and absorption �0.40, with no apparent segregation. This requirement includes separating crushed concrete aggregate according to its original coarse aggregate type, except for the following situations: 1. Different aggregate types may exist in the same stockpile if the quantities by weight of each aggregate type retained on the No. 4 sieve do not differ by more than �10 percent from the average quantity obtained from at least three representative samples. 2. When aggregate is produced from concrete pavement with only one aggregate type that has been repaired with concrete patches with a different aggregate type. 902.04 Coarse Aggregates for HMA Mixtures. Use natural aggregate, iron blast furnace slag, reverberatory furnace slag, steel furnace slag, or crushed concrete meeting the grading and physical requirements in the contract documents.

34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Yes). Contractors become owners and generally do not use in project but rather use it in their private work. The following is the Michigan Special Provision for recycling:

03SP501(G) MICHIGAN DEPARTMENT OF TRANSPORTATION SPECIAL PROVISION FOR RECYCLED HOT MIX ASPHALT MIXTURE C&T:GMM 1 of 1 C&T:APPR:JAR:MF:12-19-01 FHWA:APPR:08-06-02 Add the following subsection to Section 501.02.A.2 of the standard specifications. c. Reclaimed Asphalt Pavement (RAP) Percentages and Binder Grade Selection. The method for determining the binder grade in hot mix asphalt (HMA) mixtures incorporating RAP is divided into three categories designated Tier 1, Tier 2 and Tier 3. Each tier has a range of percentages that represent the contribution of the RAP binder toward the total binder, by weight. The tiers identified below apply to both Superpave and Marshall mixtures with the following exception: Superpave mixture types E3, E3 High Stress and E10 used as leveling or top course shall be limited to a maximum of 17% RAP binder by weight of the total binder in the mixture. Superpave Mixture types E10 High Stress, and all E30 and E50 mixtures used as leveling or top course shall be limited to a maximum of 14% RAP binder by weight of the total binder in the mixture. Tier 1 ( 0% to 17% RAP binder by weight of the total binder in the mixture) No binder grade adjustment is made to compensate for the stiffness of the asphalt binder in the RAP.


C-31

Tier 2 (18% to 27% RAP binder by weight of the total binder in the mixture) The selected binder grade for the asphalt binder is one grade lower for the high temperature than the binder grade required for the specified project mixture type. For example, if the specified binder grade for the mixture type is PG58-28, the required grade for the binder in the recycled mixture would be a PG52-28. The asphalt binder grade can also be selected using a blending chart for high and low temperatures. The Contractor shall supply the blending chart and the RAP test data used in determining the binder selection. Tier 3 ( A 28% RAP binder by weight of the total binder in the mixture) The binder grade for the asphalt binder is selected using a blending chart for high and low temperatures. The Contractor shall supply the blending chart and the RAP test data used in determining the binder selection.

Have difficulty meeting Superpave specifications Notes Most PCC is 11 to 12 inches thick, ACP bound layers are 12 to 15 inches Generally when BSEAL’s are above 10 million, the LCCA favors PCC.

Appendix C – Minnesota

C-32

Purpose The purpose of this interview is to gain insight into the following Minnesota Department of Transportation practices:


Agency Interviewed Minnesota Department of Transportation 1400 Gervais Ave. Maplewood, MN 55109-2044 Person(s) Interviewed

Name Title Phone Email Dave Van Deusen

Pavement Design/Grading and Base Engineer


Dave Janisch Pavement Management Engineer



New Construction: Yes Reconstruction: Yes Rehabilitation: Unbonded overlays

2. How long have you used the current type selection procedure? Issued in 1997 and modified in 2001 3. Changes made over the last 5 years: Modified in 2001 to increase the BESAL’s from 7 million to 10 million before pavement automatically went PCC. Process is currently being further modified.

What prompted the change? Request of the HMA industry 4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? No


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5. Importance and extent of industry involvement in the development of type selection process? Both industries serve as non-voting members on committee responsible for recommending changes. 6. How was the selection process implemented within the agency? Commissioner issues policy 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? No 8. Pavement types used for new construction or reconstruction over the last 5 years



Full depth ACP Deep Strgth ACP X* X Generally good, thermal cracking and

stripping have been prob. ACP(less than 6”) agg base

Jointed Plain (JPCP) X* X Generally good now. Using a premium design on high volume routes. Low w/c concrete and stainless steel clad dowels



*Mileage data not readily available, but most Interstate reconstruction goes concrete because design traffic exceeds 10 million BESAL’s


ACP: Modified AASHTO PCCP: AASHTO 86

10. What design life used for each pavement type?

Flexible – 20 years Rigid – 35 years

11. Are there different foundation/base requirements for AC and PCC? Flexible design requires subbase and minimum 30-inch total pavement thickness Rigid 12 inches select material and 4-inch granular base


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12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Use same smoothness criteria based on profilograph. Plan to change to and IRI specification. Modified flexible procedure does not directly consider initial serviceability 13. Typical costs and method of contract measurement

ACP in place $/_______43_______/ton sy cy other JPCP (slab only) $/________*_____sy cy other JRCP (slab only) $/_____________sy cy other CRCP (slab only) $/_____________sy cy other

* Concrete pavements are paid for based on a combination of surface area of concrete pavement specified and the volume based on planned thickness and the computed area of pavement. Typical for 13-inch pavement was $19/sy plus $58.10/cy 14. How important is first cost versus future costs? Straight LCCA 15. Is life cycle cost analysis used? Yes – Agency costs only 16. Analysis period 35 years currently, going to 50 years 17. Discount Rate (how established) Current 4.5 %, but going to OMB A94 18. Initial Costs – Estimating procedure Not bid unit cost based. Do cost estimates based materials costs at project site. Process looks at factors such as aggregate costs, haul, and construction costs. Additional costs for premium enhance designs are not included in the initial analysis. These features are included after pavement type has been selected.


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Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)

Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) N

2. Highway functional class N 3. Traffic Y P %


N

5. Construction considerations N

a. Staging N b. Clearance for equipment N c. Construction operations N

d. Traffic operations during construction N

e. Construction seasons N


C-36

Factor

Con

side

red

Prim

ary

or S

econ

dary

Impo

rtan

ce (0

to 5

)


(maintenance of traffic, ease of maintenance) N


8. Availability of local materials, contractor’s capabilities,

and experienced agency personnel. N

9. Pavement Continuity N

a. Adjacent sections N b. Adjacent lanes N

10. Noise issues N 11. Subgrade soils N 12. Climate N 13. District or local preference N 14. Ease of maintenance N 15. Recycling N

16. Conservation of materials and energy N

17. Stimulation of Competition N

18. Safety considerations (rutting, friction, lighting, etc) N

19. Smoothness N


C-37

19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. Project based. 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. No 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) No 22. Routine maintenance (how estimated, operations included) Rout and seal cracks, Joint reseal, minor CPR are included. Based on estimates by District Engineers 23. Rehabilitation (how is timing estimated, techniques used, etc.) Mill and Overlay, Major CPR, Some full depth and Grinding. Based on estimates by District Engineers and performance history in PMS database.

Salvage Value (remaining life): New System will consider for PCC high performance design. None for HMA. Residual value (recycling): No Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Consider for original construction Engineering and administration: No

24. How are users costs weighted in relation to agency costs? Not considered now. Plan to look at for future up date. 25. Vehicle operating costs 26. User Delay 27. Description of the analysis process 28. Routine maintenance Reactive


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29. Preventive maintenance Crack and joint sealing, minor CPR other than full depth patching, surface treatments, overlays less than 2 inches 30. What are the states standard routine and preventive maintenance operation and schedule by pavement type? 31. Allocation of resources between maintenance, rehab, new and reconstruction Districts allocate as needed. However, $40 million is allocated statewide to preventive maintenance. 32. Do you have a formal system to track pavement condition, cost, and survivability? Yes. Have targets for percent pavements in good category and percent with a remaining life of 12 years. 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes into aggregate base, and subbase. Contractors can’t meet the w/c ratio requirements if used in PCC 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? 30% max in wearing course 50% max on wearing course mixes However, mixes must meet mix design specification requirements

Appendix C – New York

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Purpose The purpose of this interview is to gain insight into the following State of New York Department of Transportation practices:


Agency Interviewed State of New York, Department of Transportation 1220 Washington Avenue Albany, NY 12232-0861 Person(s) Interviewed

Name Title Phone Email Russell Thielke, P.E. Head, Materials Bureau 518-457-4582 [email protected] Brad Allen, P.E. Engineer, Materials Bureau 518-457-4582 [email protected] Mike Brinkman Engineer, Materials Bureau 518-457-4582 [email protected]


New Construction: Yes. For new construction, consult Chapters 3 and 5 of the New York Comprehensive Pavement Design Manual. Available on the web. Reconstruction: Yes. For reconstruction, consult Chapters 3 and 5 of the New York Comprehensive Pavement Design Manual. Available on the web. Rehabilitation: Yes, there are two manuals. DKH provided with copies. They are also included as chapters in the Comprehensive Pavement Design Manual.

2. How long have you used the current type selection procedure? Rehabilitation has been in effect since 1989. The Comprehensive Pavement Design Manual was published in 2000. The manual brought together all of the designer’s tools into one comprehensive document. 3. Changes made over the last 5 years: On-going minor changes but nothing significant.

What prompted the change? Treatment selection hasn’t changed much but will in 2004.


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4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? No. Alternative bidding has not been used. 5. Importance and extent of industry involvement in the development of type selection process? Industry doesn’t have much involvement in pavement type selection. The industry tends to partner with the DOT in the review of new technology, specifications changes, etc. The industry has not generally questioned the State’s decisions on pavement type selection. 6. How was the selection process implemented within the agency? NY DOT started with the suggestions provided in the AASHTO 1993 Guide and modified them for NY State conditions. LCCA is used and at least 2 alternatives are evaluated for each project. 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? Project by project selection. The initial costs usually drive the selection process. The designs are done at the regional level and they are each provided with a pot of money. The central office reviews designs but generally in a cursory way. The regions have the autonomy to choose pavement type and to pay higher initial costs in favor of lower future maintenance if desired. 8. Pavement types used for new construction or reconstruction over the last 5 years



Full depth ACP 90 percent Good Deep Strgth ACP 0 ACP(less than 6”) agg base 0 Jointed Plain (JPCP) 10 % Good Jointed Reinforced (JRCP) 0 Continuously Reinf. (CRCP) 0


ACP – AASHTO 1993 as modified for New York State. Included in the Comprehensive Pavement Design Manual. PCCP – AASHTO 1993 as modified for New York State. Included in the Comprehensive Pavement Design Manual.

http://www.dot.state.ny.us/cmb/consult/cpdmfiles/cpdm.html


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10. What analysis period used for each pavement type? 50 years for new construction 30 years for rehabilitation 11. Are there different foundation/base requirements for AC and PCC? They are treated the same. 12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Initial serviceability is not directly considered in the modified procedure. Smoothness specifications for PCC require the use of the California Profilograph with a 5 mm blanking band to measure smoothness. There are no smoothness requirements for flexible pavements. They are working on an IRI based acceptance criteria for flexible pavements and may use this for rigid pavements as well although they are sensitive to the issues of using a light weight profiler on tined concrete surfaces. 13. Typical costs and method of contract measurement Varies widely and depends on local conditions. Typically, HMA is $ 30 - $ 80 /metric tonne and concrete is $ 140 to $ 250 per cubic metre. All designs and payment, etc. in New York is done in metric.

ACP in place $/______________/ton sy cy other JPCP (slab only) $/_____________sy cy other JRCP (slab only) $/_____________sy cy other CRCP (slab only) $/_____________sy cy other

14. How important is first cost versus future costs? Initial cost has about a 95 percent importance level. They are currently revising their pavement selection process to include probabilistic modeling and user costs so this may change. The expected date of implementation is summer 2004. 15. Is life cycle cost analysis used? Yes 16. Analysis period 50 years for all new construction and reconstruction 30 years for all rehabilitation


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Factor

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Comments 1. Roadway/lane geometrics (lane widths, cross slopes, ability

to provide drainage) Y P 5 2. Highway functional class Y P 5 3. Traffic Y P 5 4. Roadway peripheral features (overhead clearance, weigh-in-

motion, guardrails, etc) Y S 5 5. Construction considerations

a. Staging Y S 3 b. Clearance for equipment N c. Construction operations Y S 3 d. Traffic operations during construction Y S 5 e. Construction seasons Y S 3


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Factor

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(maintenance of traffic, ease of maintenance) Y S 3 If the Region wants to sacrifice some of their initial cost funds to save future maintenance costs, they can do that.

7. Performance of similar pavements in the area Y S 4 Only if traffic warrants a change. They will tend to build pavements similar to others in a particular area.

8. Availability of local materials, contractor’s capabilities, and experienced agency personnel. Y S 2 Regional preference.

9. Pavement Continuity a. Adjacent sections Y S 4 b. Adjacent lanes Y P 4 Very high importance. They would not build differing adjacent lanes

10. Noise issues Y S 1

They are not very worried about noise. They have longitudinal tined sections as experiments and like the results. They also have used turf drag instead of tining but FHWA doesn’t approve.

11. Subgrade soils Y S 2 12. Climate N 13. District or local preference Y S 4 Regions can have local preference. 14. Ease of maintenance N 15. Recycling N 16. Conservation of materials and energy N 17. Stimulation of Competition N

18. Safety considerations (rutting, friction, lighting, etc) Y P 5 Very cognizant of safety. 19. Smoothness N


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502-3.16 Profilograph. This section applies to profilographed projects and nonprofilographed projects when a full-width finishing pan or triple transverse screed paving operation is not employed, as discussed in §502-2.04B2, Paving Equipment. Use equipment meeting §502-2.04G, Profilograph. Provide traffic control and survey stationing for referencing measurements. The Engineer will divide the pavement into 160 m long reporting segments, but may group segments shorter than 160 m with previous or subsequent placements. The reporting segment width is the placement width. Develop a profile trace and determine an initial profile index (PI) for each travel lane of each reporting segment. Obtain the trace along the longitudinal center of the travel lane in accordance with Materials Method 24, PCC Pavement Profilograph Operations. Develop a referencing system that allows the Engineer to readily associate a trace and an initial PI to the actual corresponding reporting segment travel lane. Give the traces and initial PIs to the Engineer. The Engineer will identify bumps exceeding 10 mm in 7.6 m on each profile trace. Locate and diamond grind these bumps, if any, to 10 mm or less in 7.6 m. If no grinding is required for a given reporting segment, the initial PI may be used to determine the payable Quality Units of Smoothness Quality Adjustment per reporting segment, as discussed in §502-4.04, Smoothness Quality Adjustment. Then, up to 10% of any reporting segment’s surface area may be ground to increase the amount of Quality Units payable. This 10% includes areas ground to remove bumps exceeding 10 mm in 7.6 m. Whether diamond grinding was required through profile trace analysis, or performed as a Contractor option, reprofilograph the pavement and determine a final PI for each travel lane of each reporting segment. Give the Engineer the final profile traces and final PI determined by using both the 5 mm and zero blanking bands. The Engineer will report the final PI and payable Quality Units, if any, for each segment as discussed in §502-4.04, Smoothness Quality Adjustment. No Quality Units will be paid for a reporting segment if more than 10% of the segment’s surface area requires diamond grinding to achieve the minimum acceptable PI. If more than 20% of a reporting segment’s surface area requires diamond grinding to achieve the minimum acceptable PI, production grind the entire segment such that the minimum PI is achieved for the segment. 502-4.04 Smoothness Quality Adjustment (Profilographed Items Only). Quality Units of Smoothness Quality Adjustment, if any, payable for each reporting segment determined by the following: Quality Units (Per Segment) = (SAF - 1.00) x PCC Cubic Meters (Per Segment)

The Smoothness Adjustment Factor (SAF) from Table 502-5, Smoothness Adjustment Factors, is based on the final PI obtained for each reporting segment in accordance with §502-3.16, Profilograph. Refer to §502-3.16, Profilograph, for diamond grinding limits on Quality Unit determination. No Quality Units are computed for pavements originally specified as nonprofilographed as discussed in §502-2.04B2, Paving Equipment.


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TABLE 502-5 SMOOTHNESS ADJUSTMENT FACTORS Final Profile Index (mm/km.)

Level 1 SAF Level 2 SAF

0.0 - 16.0 1.05 1.05 16.1 - 32.0 1.04 1.04 32.1 - 48.0 1.03 1.03 48.1 - 64.0 1.02 1.02 64.1 - 79.9 1.01 1.01 80 1 1 80.0 + Grind 1 190.0 + Not Applicable Grind


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17. Discount Rate (how established) They use the OMB rate of 4 percent. This will be reviewed with the revised pavement selection methodology. 18. Initial Costs – Estimating procedure They have a unit price bid book which is updated at 6 month intervals. It contains bid prices for all contract bidders in all regions. The LCCA staff person can call up this information and decide to use averages, filtered values, etc. 19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. They have a unit price bid book which is updated at 6 month intervals. It contains bid prices for all contract bidders in all regions. The LCCA staff person can call up this information and decide to use averages, filtered values, etc. http://www.dot.state.ny.us/cmb/consult/awbpbp/awbpbp.html 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. Price adjustments are applied to HMA items only. They are not included in the LCCA. 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) No this is not done. 22. Routine maintenance (how estimated, operations included) Best guess based on local experience. 23. Rehabilitation (how is timing estimated, techniques used, etc.) Best guess based on local experience.

Salvage Value (remaining life): Included. Residual value (recycling): Not included. Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Not included. Engineering and administration: Not really considered in initial design as it is assumed that these costs would be similar for all alternatives. They do add a 27 percent overhead cost for future maintenance and rehabilitation treatments.


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24. How are users costs weighted in relation to agency costs? None used. This will change with the expected implementation of the probabilistic approach next year. 25. Vehicle operating costs None used. This will change with the expected implementation of the probabilistic approach next year. 26. User Delay None used. This will change with the expected implementation of the probabilistic approach next year. 27. Description of the analysis process Probabilistic will be used next year. Deterministic is currently being used. 28. Routine maintenance They use the term “corrective.” This includes spall repairs, pothole filling, grass cutting, sign repairs, etc. 29. Preventive maintenance See Chapter 10 of the Comprehensive Pavement Design Manual. Includes thin surface seals, crack sealing, etc. 30. Rehabilitation Includes all major items, mill and fill, unbonded overlay, rubblization, etc. 31. What are the state’s standard routine and preventive maintenance operation and schedule by pavement type? Best guess for each project type. No real standard.

Allocation of resources between maintenance, rehab, new and reconstruction— 90 percent focus on rehabilitation, 10 percent on maintenance. Not much in the way of any new construction

32. Do you have a formal system to track pavement condition, cost, and survivability? Yes. A formal pavement management system is in place.


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33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes, standard specifications allow for recycling of both asphalt and concrete. In HMA, asphalt can be recycled up to 20 percent in surface and intermediate courses and 30 percent in base courses. Concrete can be recycled into base/subbase. http://www.dot.state.ny.us/specs/2002specbook.html 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Yes, standard specifications allow for recycling of both asphalt and concrete. In HMA, asphalt can be recycled up to 20 percent in surface and intermediate courses and 30 percent in base courses. Concrete can be recycled into base/subbase. http://www.dot.state.ny.us/specs/2002specbook.html

401-2.05 Reclaimed Asphalt Pavement. Reclaimed Asphalt Pavement (RAP) will meet the requirements as written in MM 5.16. 304-2.02 Material Requirements. Provide suitable material conforming to the requirements of Section 203 and to the requirements contained herein. Provide a subbase material which meets the specification material requirements and is within the Contractor’s capabilities to place and fine grade to the required tolerances. Should the subbase course become unstable at any time prior to the placement of the overlying course, correct the unstable condition to the satisfaction of the Engineer at no additional cost to the State. Perform any required modification prior to placing the material on the grade. If used, glass shall conform to the applicable paragraph of Section 203. If RCA is used and it comes from other than a Department of Transportation project, provide documentation showing that the material obtained is from a NYSDEC registered or permitted construction and demolition (C&D) debris processing facility as specified in Section 360-16.1 of 6NYCRR Part 360, “Solid Waste Management Facilities”. If Blast Furnace Slag is to be used, provide documentation showing that it has undergone a NYSDEC beneficial use determination (BUD) prior to its use as specified in 6NYCRR Part 360-1.15, “Solid Waste Management Facilities”. For Types 1, 3 and 4 furnish materials consisting of approved Blast Furnace Slag, Stone, Sand, and Gravel, or blends of these materials with not more than 30 percent by weight of glass. Alternately, the following materials are also acceptable under these types as a replacement for the materials mentioned above:


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! Alternate A. At least 95 percent, by weight, of RCA, and free from organic and other deleterious material. This material may contain up to 5% by weight asphalt and/or brick. ! Alternate B. A mixture of RCA conforming to Alternate A above mixed with stone, sand, gravel or blast furnace slag. This material may contain up to 5% by weight asphalt and/or brick. ! Alternate C. Bituminous material that is reclaimed from bituminous pavement and/or shoulders (Reclaimed Asphalt Pavement, or RAP) on a project constructed by the Department of Transportation and is well-graded from coarse to fine and free from organic or other deleterious material, including tar. This material is at least 95 percent, by weight, reclaimed bituminous material and has a maximum top size, at time of placement, of 50 mm. The gradation requirements for the different Types listed below do not apply when the material consists of RAP. No soundness or Plasticity Index testing will be required for this Alternate. For Type 2, furnish materials consisting of approved Blast Furnace Slag or of Stone which is the product of crushing or blasting ledge rock, or a blend of Blast Furnace Slag and of Stone. If, in the opinion of the Regional Geotechnical Engineer, this material becomes unstable during construction, it may be necessary to add a mixture of natural suitable material to the RAP. Acceptance of the final product shall be based on an evaluation by the Regional Geotechnical Engineer. Provide written documentation that the reclaimed bituminous material originated on a Department of Transportation project. Include an identifier, such as State Highway, Construction Contract or Departmental Project Identification Number (PIN).

Appendix C – Ontario

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Purpose The purpose of this interview is to gain insight into the following Ontario Ministry of Transportation practices:


Agency Interviewed Ontario Ministry of Transportation 1201 Wilson Avenue Central Building, Room 232 Toronto, Ontario M3M 1J8 CANADA Person(s) Interviewed Name Title Phone Email Tom Kazmierowski Manager, Pavements and

Foundation Section 416-235-3512 [email protected]


New Construction: Yes – ERES Report Reconstruction: Yes – ERES Report Rehabilitation: Yes – for major rehabilitation - ERES

2. How long have you used the current type selection procedure? 1998 but other processes before that to the early 1970s. 3. Changes made over the last 5 years: A Geokom document spells out the need for pavement alternative selection for all projects.

What prompted the change? The change was prompted by changes in technology and the desire to go to alternative bidding.

4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? Yes. Alternative bidding was used for one project to date. All current projects that are at least 10 km in length and have at least 1 million ESALs in the design lane or are likely to have 1 millions ESALs in the design lane in the next 5 years are serious considered for alternative bid.


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5. Importance and extent of industry involvement in the development of type selection process? This is very important to MTO. The industry (Cement Association of Canada) and the Ontario Hot Mix Producers Association has been extensively involved in the pavement type selection process and sit on the evaluation committee. This is an on-going process and the committee met this week in Toronto to discuss developments including the expected inclusion of user costs. They are also consulted on new technology developments and specification changes. 6. How was the selection process implemented within the agency? It is done early in the process and is an integral part of the design process. It generally follows the schematic outlined in AASHTO 1993. Industry and consultant teams are involved in the implementation. 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? It is done early in the process and is an integral part of the design process. It generally follows the schematic outlined in AASHTO 1993. 8. Pavement types used for new construction or reconstruction over the last 5 years



Full depth ACP < 1 % Fair Deep Strgth ACP 95 % Good ACP(less than 6”) agg base

0

Jointed Plain (JPCP) <5 % Good Jointed Reinforced (JRCP)

0 There are old JRCP but they are all now composite as they have been overlaid with HMA.


0


ACP: AASHTO 1993 Modified for Ontario Conditions Ontario Pavement Analysis of Costs MTO Routine Method for low volume roads PCCP: AASHTO 1993 Modified for Ontario Conditions Ontario Pavement Analysis of Costs Portland Cement Association


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10. What analysis period used for each pavement type? 50 years for high volume freeways 30 years for secondary highways and rehabilitation 11. Are there different foundation/base requirements for AC and PCC? No. 12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Yes. 13. Typical costs and method of contract measurement Difficult to determine. It is regional and contract specific.

ACP in place $/______________/ton sy cy other JPCP (slab only) $/_____________sy cy other JRCP (slab only) $/_____________sy cy other CRCP (slab only) $/_____________sy cy other

14. How important is first cost versus future costs? They are weighted the same and used in the LCCA. The LCC dominates the decision process. 15. Is life cycle cost analysis used? Yes 16. Analysis period 50 years new and reconstruction 30 years rehabilitation 17. Discount Rate (how established) Ministry of Finance (similar to OMB) social discount rate for infrastructure. The current rate is 5.3 percent and they suggest a 2 percent sensitivity level.


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Factor

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Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) Y P 5 Is a given with all designs.

2. Highway functional class Y P 3 3. Traffic Y P 5

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc) Y S 3

5. Construction considerations a. Staging Y S 3 Is considered but minimal impact. b. Clearance for equipment N c. Construction operations Y S 2

d. Traffic operations during construction Y S 3 e. Construction seasons Y S 2 Scheduled to prevent late season paving.


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(maintenance of traffic, ease of maintenance) Y S 3

7. Performance of similar pavements in the area Y P 4 Tend to keep similar pavement types together.

8. Availability of local materials, contractor’s capabilities, and experienced agency personnel. Y P 5 If materials or expertise is not available, it will drive up costs.

9. Pavement Continuity a. Adjacent sections Y P 4 b. Adjacent lanes Y P 5 Would not put significantly differing materials in adjacent lanes.

10. Noise issues Y P 3 MTO has a policy on noise and pavement type. 11. Subgrade soils Y P 5 12. Climate Y S 4 13. District or local preference Y S 2 Regions can exercise local preference on a project by project basis 14. Ease of maintenance Y S 2 15. Recycling Y P 3

16. Conservation of materials and energy Y P 3 17. Stimulation of Competition Y P 3

18. Safety considerations (rutting, friction, lighting, etc) Y P 5 19. Smoothness Y P 3


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18. Initial Costs – Estimating procedure HiCo (Highway Cost) database is used. Contains an average of 3 lowest bids on recent projects in each regional area. Designer has the ability to review the prices to see what are reasonable for the project area. 19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. HiCo (Highway Cost) database is used. Contains an average of 3 lowest bids on recent projects in each regional area. Designer has the ability to review the prices to see what are reasonable for the project area. The costs are updated electronically continuously and are kept for the past 10 + years. 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. Yes. Most materials and placement have price adjustment. They are not included in the LCCA. 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) Only bid costs are used. 22. Routine maintenance (how estimated, operations included) Includes items such as ditching, grass cutting, etc. These are considered similar for all options and are not included in the LCCA. 23. Rehabilitation (how is timing estimated, techniques used, etc.) Based on LCCA models developed by a consultant (ERES) in conjunction with MTO and industry representatives. Based on serviceability levels, trigger values and performance measures.

Salvage Value (remaining life): Included. Residual value (recycling): Not included. Considered equal for all pavements. Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Not included. Part of normal design, not LCCA. Engineering and administration: Not included in LCCA. Assume that everything outside of the pavement section is the same. Not include in initial or future costs.

24. How are users costs weighted in relation to agency costs? Not used currently. Will likely be in 2004.


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25. Vehicle operating costs Not used currently. Will likely be in 2004. 26. User Delay Not used currently. Will likely be in 2004. 27. Description of the analysis process 28. Routine maintenance Shoulder grading, ditch cleanout, pothole filling, spall repairs, etc. 29. Preventive maintenance Crack sealing, surface seals, selective resurfacing (area patching), thin lift resurfacing, hot in-place recycling, micro-surfacing, NovaChip, Dynapatch, slurry seals, etc. 30. What are the state’s standard routine and preventive maintenance operation and schedule by pavement type? See ERES Benefits of New Technology Report

31. Allocation of resources between maintenance, rehab, new and reconstruction Current focus is on rehabilitation and preventive maintenance. Not much new construction. 32. Do you have a formal system to track pavement condition, cost, and survivability? Yes. Detailed pavement management system. 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes. 100 percent can be recycled into base/subbase. 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Yes. 30 percent can be recycled into base/subbase. Percentage in HMA varies from about 10 to 30 percent depending on the type of mix.

Appendix C – Pennsylvania

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Purpose The purpose of this interview is to gain insight into the following Pennsylvania Department of Transportation practices:


Agency Interviewed Pennsylvania Department of Transportation 400 North Street Sixth Floor Harrisburg, PA 17101-1900 Person(s) Interviewed

Name Title Phone Email Mr. Dan Dawood Chief, Pavement Analysis &

Design Section (717) 787-4246 [email protected]

Overview of Procedure and General Notes: The life cycle cost procedure is documented in a manual from the Pavement Design Analysis Section. The life cycle cost analysis procedure is in the form of an excel spreadsheet and is performed on all interstate project exceeding $1M and all other projects exceeding $10M, regardless of the funding source. A deterministic approach is used, and the inputs represent the median values, rather than the average values. The software can be obtained from PennDOT from their website. The procedure has been recently updated and can be downloaded from the Pennsylvania DOT website. FHWA is currently reviewing the updated procedure. The current update was prepared to answer questions and issues that had been raised by industry related to pavement type selection. The Department is considering adding a probabilistic approach to the procedure, but that has yet to be completed. The district determines the options to be considered. However, a field view or oversight committee that consists of district and central personnel and FHWA personnel is established that overviews the type of alternates that are considered for each project. Industry is not represented on this field view committee. The only external agency involved in the procedure is FHWA. A minimum of two alternates are considered for each project --- one PCC surfacing and one HMA surfacing option. The types of options that are considered consist of a decision between pavement preservation and reconstruction unless it is a new alignment project. The options for reconstruction are listed below.


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• Jointed plain concrete pavements with a 4-inch open-graded drainage layer stabilized with asphalt or cement. If 10 percent patching is required, this is considered total reconstruction.

• Full-depth hot-mix asphalt concrete pavements – a drainage layer is not required for the HMA pavement. If there are severe distresses (rutting and cracking), this is considered total reconstruction.

Rubblization is not used that much in Pennsylvania. However, crack and seat is used quite extensively. The crack and seat includes sawing the PCC slabs and cutting the steel. In some cases, the LCCA can be waived depending on the structure of adjacent lanes or adjoining sections with the same type of surface. Chapter 11-1 in the Pavement Design Analysis Manual gives a summary of when the rules can be bent or waived. Composite pavements are not considered and there is no bin with the LCCA for considering this type of pavement structure. The LCCA procedure is used to calculate the present worth costs for each alternate. Equivalent annual costs have been used on very few projects. If the cost between the two alternatives has a difference of greater than 10 percent, the alternative with the lowest costs is selected, unless the district has some reason for selecting the other alternative, which does not happen very often. If the cost between the two alternatives is less than 10 percent, the district selects the option based on other factors. The district executive reviews the recommendation and approves or rejects the recommendation. In most cases the district executive approves the recommendation. The final recommendation then goes to the central office for review and concurrence. User costs for initial construction are not considered as part of the LCCA because it is assumed that they will be equal for all alternatives. This assumption is dependent on the type and number of structures that occur along the project length. 1. Do you have a documented pavement type selection procedure for:

New Construction – Yes and it is documented in Chapter 11 of the Life Cycle Cost Analysis Procedure of the Pavement Design Analysis Manual. Reconstruction – Yes and it is documented in Chapter 11 of the Life Cycle Cost Analysis Procedure of the Pavement Design Analysis Manual. Rehabilitation – Yes and it is documented in Chapter 11 of the Life Cycle Cost Analysis Procedure of the Pavement Design Analysis Manual.

The following types of design strategies, new construction and rehabilitation by surface type are considered as part of the LCCA: Bituminous Pavements: HMA or bituminous overlay

HMA overlay – crack-n-seat HMA Reconstruction – Rubblization HMA Reconstruction – Remove & replace


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PCC Pavements: Concrete pavement rehabilitation

Bonded & Unbounded PCC overlays PCC overlays – Unbounded; crack-n-seat PCC Reconstruction – Rubblization PCC Reconstruction – Remove & replace

2. How long have you used the current type selection procedure? The procedure was developed around 1985. It is about 18 years old. The current procedure has been automated and the software is available for use from the PennDOT website. However, there is no periodic review of the procedure. 3. Changes made over the last 5 years: The maintenance schedules and initial service lives are routinely updated from data that has been collected through or for their pavement management system. In addition, the difference in costs between two alternatives of 5 percent was increased to 10 percent during the last update.

What prompted the change? New data had been collected for their pavement management system and to answer questions or concerns that the asphalt industry had on the procedure regarding the comparison of different alternatives

4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? The Pennsylvania DOT does not plan to use the alternative bidding process in the future. The Department has used the alternative bidding process once, which is on-going. This is a federal aid project, but has yet to be reviewed and approved by FHWA. This project has two alternatives which have a 3 percent cost difference between the two alternatives, based on the engineers estimate. This first project is considered to be a pilot project. However, the Department has no intentions to continue or implement this process in the future. 5. Importance and extent of industry involvement in the development of type selection process? Industry was not involved in the development of the life cycle cost analysis procedure. Industry is only involved when they ask to be involved. FHWA is the only external agency involved in the process. The Department wants two strong industries in Pennsylvania from a competitive standpoint.


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6. How was the selection process implemented within the agency? The Department developed the process or procedure in-house without involving industry. The LCCA is completed at the district level. The district engineer recommends the pavement type to be considered from the LCCA. The recommendation is forwarded to the district executive. The district executive recommends the selection to the central office for review. The central office evaluates the recommendation and forwards the recommendation to the FHWA for concurrence. 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? There is no interrelationship between project selection, budgeting and planning within the pavement type selection process. The budget is predetermined for each project. The Department assumes that both or all alternatives considered within the LCCA procedure provide the same benefit to the DOT. The winning bid for the construction project must be within 10 percent of the engineers estimate. If the bid is greater than 10 percent of the engineers estimate, then the project is pulled, evaluated and re-advertised. However, the pavement type selection will not change once established for a particular project. 8. Pavement types used for new construction or reconstruction over the last 5 years



Full depth ACP This group really falls under ACP with 6-inch or less aggregate base.

Deep Strgth ACP Does not use asphalt treated base layers.

ACP(less than 6”) agg base

75 – 125 225 – 250 Within the last 2 to 3 years. Rated between good to fair. The Department has had some problems with Superpave mixes in the past.

Jointed Plain (JPCP) 450 – 500 225 – 275 Rated between good to fair. The Department has had some problems on a few projects with mid-slab cracking.


Does not use this type of pavement.


Does not consider this type of pavement.


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9. Thickness design procedure used and design life (if AASHTO which version) A 20-year design period is used for both ACP and PCCP.

ACP: The 1993 AASHTO Design Guide is used. In addition, the Department uses a frost factor for designing ACP. This frost factor is separate from the DARWin program. The increase in pavement structural thickness is applied to the HMA base thickness. The Department does not like to use more than 12 inches of an unbound aggregate base material for any design or roadway. The standard deviation used in design is 0.45. Moisture coefficients are also used in the design and are dependent on the type of material. The following table summarizes the layer coefficients that are used in the procedure.

Layer Material Type Structural Layer Coefficient

Superpave 0.44 ID-2, ID-3 0.44 FB-1, FB-2 0.20

Wearing & Binder Layers

FJ-1, FJ-1C, FJ-4 0.35 Superpave 0.40 Bituminous Concrete Base 0.40 Crushed Aggregate 0.14 Crushed Aggregate, Type DG 0.18 Bituminous Base 0.30 Aggregate Cement Base 0.40

Base Layer

Aggregate Lime Base 0.40 Open-Graded 0.11 No. 2 Subbase 0.11 Asphalt Treated Permeable Base 0.20 Cement Treated Permeable Base 0.20

Subbase Layer

Rubblized PCC 0.20 PCCP: The 1993 AASHTO Design Guide is used. The frost factor used or considered in the design of ACP is not used or considered in PCCP designs. The average 28-day flexural strength used in design is 631 psi, and the modulus of elasticity is 4,000,000 psi. However, the District can use other values based on their experience and data. A loss of support is used in design --- values of 0.5 and 1.0 are used and depend on the material. The standard deviation used is 0.35.

10. What analysis period used for each pavement type? A 40-year analysis period is used for both ACP and PCCP. 11. Are there different foundation/base requirements for AC and PCC? Yes, as noted below.


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• Subgrade preparation is the same for all alternatives. Lime or lime-fly ash stabilization is considered for both ACP and PCCP. This subgrade stabilization process is being used more routinely in Pennsylvania. The stabilization process has provided good performance in areas with frost susceptible or very weak soils. The Department has over-excavated frost susceptible soils for both pavement types. This is the other process that is being used to improve the subgrade foundation for both pavement types. The subgrade improvement process used is the same for both or all alternatives of a project or LCCA procedure.

• The ACP alternative, however, always includes a 6 to 8-inch dense- graded aggregate base for thick HMA bases (greater than 7 inches), but not for PCCP.

• The PCCP alternative always includes a 4 to 6-inch asphalt or portland cement open-graded drainage layer under PCCP, but not under ACP.

12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? No. The following summarizes the values used in design for ACP and PCCP.

PSI-Value for LCCA and Design

Roadway Type PCCP ACP

Interstate or Limited Access Roadways

4.5 4.2 Initial Value

All Other Roadways 4.5 4.2 Interstate or Limited Access Roadways

3.0 3.0

All other 4-lane Roadways

2.5 2.5

Terminal Value

Local Roadwdays 2.0 2.0 NOTE: However, the department uses a lower IRI-value for ACP in accepting pavement construction as part of their acceptance program. The IRI-value for PCCP is higher because of the tinning requirements.

The above values are given in Chapter 6-12 of the Pavement Design Analysis Manual.

13. Typical costs and method of contract measurement

ACP in place $/____See below__________/ton sy cy other HMA Thickness, inches Layer Type In-Place Costs, $/sy 1.5 Wearing Surface 4.5 to 5.5 2 Binder Layer 6.25 to 6.8 5 to 7 Base Layer About 7.0 NOTE: The Department pays for the binder separately. The binder costs is not included in the in place cost tabulated above. The cost for the liquid asphalt includes a price adjustment factor for HMA. The costs noted above have been reasonably stable over the past years. JPCP (slab only) $/___65 to 75__________sy cy other Price adjustment factors for PCCP are not used. JRCP (slab only) $/____NA_________sy cy other CRCP (slab only) $/____NA_________sy cy other


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14. How important is first cost versus future costs? The Pennsylvania DOT does not use any kind of scoring system in selecting the pavement surface type. It is based on the total life cycle costs for each alternate or option. Present Worth cost is what matters and used in selecting the type of pavement. First costs and future costs is an issue, but not considered --- not open for discussion. 15. Is life cycle cost analysis used? Yes. As noted above, the total life cycle costs for each alternate or option to select the type of design strategy or type of pavement surface. 16. Analysis period The analysis period is 40 years for both types of pavements or for each design strategy considered in the LCCA. 17. Discount Rate (how established) A discount rate of 6 percent is used. Industry has complained with the value, but has not been changed since the procedure was developed. This value is considered fixed but could be up for future consideration. 18. Initial Costs – Estimating procedure The Department does not have an estimating procedure. The unit costs for each cost item are collected from the bid items. The median value for each cost item is used in the LCCA. 19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. The unit costs are complied for every bid item on a state wide basis and stored in the Contract Management System (CMS) database. These costs can be broken down by district, quantities, high and low bids, averages of all winning bids. The age of the price data is updated after every letting. 20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. For ACP, price adjustment factors are used. For PCCP, price adjustment factors are only considered for the HMA permeable base layers. The price adjustment factors are not used directly in the LCCA, but are indirectly included in the cost computations.


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Factor

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Comments 1. Roadway/lane geometrics (lane widths, cross slopes,

ability to provide drainage) Yes S 2 Steep grades can be a factor if the difference in cost between the two alternatives in less than 10 percent.

2. Highway functional class No Generally defines that a LCCA should be done; i.e.; interstate and limited access roadways.

3. Traffic; Truck Overall Traffic

Yes Yes

P S

3 3

These items or factors are considered when there is less than a 10 percent difference between the costs.

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc) Yes S 3

5. Construction considerations a. Staging Yes P 3 b. Clearance for equipment No

c. Construction operations No This factor maybe considered in the future based on comments or complaints from industry.

d. Traffic operations during construction Yes S 3

A factor that is considered, but most traffic control and delay costs are assumed to be equal between each alternate or option for initial construction.

e. Construction seasons No 6. Consideration of future maintenance operations

(maintenance of traffic, ease of maintenance) Yes P 5 Definitely has an effect on the user or delay costs for the maintenance cycling and cost of the maintenance.

7. Performance of similar pavements in the area Yes P 4

Considered on a project by project bases. This factor is implemented on a system wide analysis and will change the maintenance cycles, and can have a significant effect on the LCCA. These are updated on a 4 to 5 year basis.


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Factor

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Comments 8. Availability of local materials, contractor’s capabilities,

and experienced agency personnel. No

9. Pavement Continuity Pavement continuity factors do have an effect but only when the cost difference between the two options are less than 10 percent.

a. Adjacent sections Yes S 2 b. Adjacent lanes Yes S 2

10. Noise issues Yes S 2

11. Subgrade soils Yes S 2 The foundation for all pavement designs or options must have a good foundation, which is considered in design.

12. Climate No 13. District or local preference Yes S 4 When the costs difference is less than 10 percent. 14. Ease of maintenance Yes S 4 When the costs difference is less than 10 percent.

15. Recycling No However, this factor could have an effect on the rehabilitation strategy selection.

16. Conservation of materials and energy No

17. Stimulation of Competition Yes S 5 [More than just those projects where the difference in costs is less than 10 percent.]

18. Safety considerations (rutting, friction, lighting, etc) Yes S 4 When the costs difference is less than 10 percent. 19. Smoothness Yes S 4 When the cost difference is less than 10 percent.


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21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) Not during the LCCA process or within the LCCA procedure. Overruns are evaluated from a CMS construction management systems approach. 22. Routine maintenance (how estimated, operations included) Routine maintenance if included from a pavement surface type. The type and timing of the routine maintenance applications if obtained from the maintenance department. This information and data are included in the Maintenance Operations Reporting Information System (MORIS). The following lists the annual maintenance costs for each surface type. The maintenance and rehabilitation activity time lines are included as figure 1.

Pavement Surface Type Annual Maintenance Cost, $/Lane Mile PCCP 825 ACP 1,825

23. Rehabilitation (how is timing estimated, techniques used, etc.) The type and timing of the rehabilitation activities for a pavement surface type is determined though the data included in the pavement management system database. The median values are included in the LCCA. This information is input initially from the county managers. The resurfacing schedule can be shortened but not extended on high-volume heavy truck routes based on the district’s experience. Currently the type of approach is solely based on the PMS data. The following lists the time to first resurfacing and the interval between resurfacings.

Pavement Surface Type Time to First Resurfacing, yrs. Interval of Resurfacing, yrs. PCCP 30 10 ACP 10 10

Salvage Value (remaining life): No, none is used or considered in the LCCA. Residual value (recycling): No, none is used or considered in the LCCA. Construction traffic control (crossovers, added lanes, barriers, detours, etc.): The traffic control costs during construction are considered to be equal between the different options or alternatives. Engineering and administration: No, none is used or considered in the LCCA.

24. How are users costs weighted in relation to agency costs? No; Agency costs are not considered. 25. Vehicle operating costs Yes the vehicle operating costs are a part of the user delay costs. Idling costs, stopping costs, and time value costs are determined by vehicle type. An inflation factor is determined by vehicle class and multiplied by the time value costs. This is described and discussed in the appendix and Chapter 11.6 of the Pavement Design Analysis Manual.


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26. User Delay User delay costs are not considered for initial construction, but are included for the maintenance cycling and rehabilitation times. 27. Description of the analysis process A detailed analysis of the maintenance cycles are done and related to traffic control, user patterns, etc. 28. Routine maintenance Refer to figure 1 as summarized in the Pavement Design Analysis Manual. 29. Preventive maintenance Refer to figure 1. Basically mill and fill; more rehabilitation type activities are noted in the manual and in figure 1. 30. What are the states standard routine and preventive maintenance operation and schedule by pavement type? See figure 1 (next page). These are defined by the central office from the database. 31. Allocation of resources between maintenance, rehab, new and reconstruction No; built into the maintenance cycles. 32. Do you have a formal system to track pavement condition, cost, and survivability? The PMS database is used for performance. The RMOIS is used for the maintenance cycles and costs. 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes, as an aggregate base, but only used as backfill for structures. Recycled PCC is not used or allowed in the PCC mixtures. 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Yes, 15 percent is allowed in HMA mixtures. This material is used heavily is shoulders and widening projects and as unbound aggregate base materials.


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Pavement Type

Activity and Time in years of Activity

5 10 15 20 30 35 New Bituminous, Bit. Reconstruction & Bit. Overlay

Seal coat Shoulders or do nothing as defined by mix type.

1.5 – 2.0 in. mill & fill; full-depth patches over 2% of area; saw & seal joints; seal coat shoulders; maintenance. & protection of traffic; user delay.

Seal coat shoulders depending on mix type.

Full-depth patches over 2% of area; HMA leveling course; saw & seal joints; adjust rails & drainage features; Type 7 paved shoulders; maintenance & protection of traffic; user delay.

Same as for 10 years. Seal coat shoulders.

5 10 15 20 30 35 New PCCP, reconstruction, & Unbounded concrete overlays

Clean & seal 25% of longitudinal joints & 5% of transverse joints; seal coat type 1 paved shoulders.

Concrete patch 2% of area; diamond grind 50% of area; clean & seal all longitudinal & transverse joints; maintenance & protection of traffic; user delay.

Concrete patch 5% of area; clean & seal all joints; HMA leveling course; 3.5-4 inch HMA overlay; saw & seal joints in overlay; type 7 paved shoulders; adjust rails & drainage features; maintenance & protection of traffic; user delay.

Seal coat shoulders.

5 10 15 20 25 30 35 PCCP Bonded Concrete Overlay

Clean & seal 25% of longitudinal joints & 5% of transverse joints.

Concrete patch over 5% of area; spall repair over 5% of transverse joints; diamond grind 10% of area; clean & seal 25% of longitudinal joints & 10% of transverse joints; seal coat shoulders (Type 6 or 7); maintenance & protection of traffic; user delay.

Clean & seal 25% of longitudinal joints & 10% of transverse joints; seal coat shoulders.

Concrete patch over 10% of area; spall repair 10% of transverse joints; slab stabilization of 25% of transverse joints; diamond grind 100% of area; clean & seal all joints; type 6 shoulders; maintenance & protection of traffic; user delay.

Clean & seal 25% of longitudinal joints & 10% of transverse joints; seal coat type 6 shoulders.

Concrete patch 2% of area; clean & seal all joints; HMA leveling course; 3.5-4 inch HMA overlay; saw & seal joints in overlay; type 7 paved shoulders; adjust rail & drainage features; maintenance & protection of traffic; user delay.

Seal coat shoulders.

5 10 18 26 32 PCCP - Restoration Seal coat

shoulders; clean & seal 25% of all joints.

Concrete patch over 25% of initial quantity; slab stabilization of 25% of initial quantity; clean & seal all joints; HMA leveling course;3.5-4 inch HMA overlay; saw & seal joints in overlay; type 6 or 7 paved shoulders; adjust rail & drainage features; maintenance & protection of traffic; user delay.

Full-depth path over 1% of area; HMA leveling course; 1.5-2 inch HMA overlay; saw & seal joints in overlay; type 7 paved shoulders; adjust rail & drainage features; maintenance & protection of traffic & user delay.

1.5-2 inch mill & fill with HMA; full-depth patch over 3% of area; saw & seal joints; seal coat shoulders; maintenance & protection of traffic; user delay.

Same as year 18.

Figure 1. Standard routine and preventive maintenance and rehabilitation schedules used in the LCCA.

Appendix C – Washington

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Purpose The purpose of this interview is to gain insight into the following Washington State Department of Transportation practices:


Agency Interviewed Washington State Department of Transportation 2655 South 2nd Avenue Tumwater, WA 98512 Person(s) Interviewed

Name Title Phone Email Linda Pierce, PE State Pavement Engineer 360 709-5470 [email protected]


New Construction - yes Reconstruction - yes Rehabilitation - no

2. How long have you used the current type selection procedure? Approximately 15 years (current procedure is under revision) 3. Changes made over the last 5 years: Probability analysis, focus on other factors (engineering, environmental, operational, and societal) and not only LCCA.

What prompted the change? Need to update 15 year old document. 4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? No


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5. Importance and extent of industry involvement in the development of type selection process? Both industries are currently reviewing and commenting on WSDOT Pavement Type Selection Protocol revision 6. How was the selection process implemented within the agency? WSDOT Directive issued by DOT Secretary requires use of a pavement type selection process on new and reconstructed pavements. 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? A new or reconstruction project is deemed necessary, during the design stage, the pavement type selection process is activated and incorporated into the final design recommendations. 8. Pavement types used for new construction or reconstruction over the last 5 years



Full depth ACP Deep Strgth ACP ACP(less than 6”) agg base

Jointed Plain (JPCP) 243 36 Good performance, approximately 210 lane miles are pending construction due to funding limitations


N/A N/A


N/A N/A


ACP – AASHTO 1993 PCCP – AASHTO 1993

10. What design life used for each pavement type? 40 years for high volume designs 11. Are there different foundation/base requirements for AC and PCC? Require use of 2 to 4 inches of HMA beneath PCCP to minimize mitigation of fines beneath PCCP.


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12. For those agencies that use smoothness as criteria do they use the same initial serviceability in design? Smoothness for PCC based on profilograph. Working on a specification covering both pavement types based on IRI. Same initial serviceability used for both pavement types. 13. Typical costs and method of contract measurement

ACP in place $/_____35_________/ton sy cy other JPCP (slab only) $/_____74________sy cy* other JRCP (slab only) $/_____________sy cy other CRCP (slab only) $/_____________sy cy other *Quantity is based on core thickness up to 0.5 inches over plan thickness

14. How important is first cost versus future costs? Equated as the same importance. 15. Is life cycle cost analysis used? Yes. Probabilistic 16. Analysis period 20 years on low volume and 60 years on high volume routes. 17. Discount Rate (how established) 4 percent, based on FHWA recommendation and OMB Circular A-94 18. Initial Costs – Estimating procedure Conducted by Project Office based on past project bid items and costs. Performed in the district office on a project-by-project basis. Reviewed by headquarters pavement design office 19. How does agency determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data. How often updated. Analysis is conducted project by project using up-to-date cost information from the bid item summary. Since many projects have varying lane configurations, ramp tapers, acceleration-deceleration lanes, etc., Project Offices are requested to conduct analysis based on a typical one-mile section.


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Factor

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Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) X S

2. Highway functional class X S 3. Traffic X S

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc) X

S

5. Construction considerations S

a. Staging X S b. Clearance for equipment X S c. Construction operations X S

d. Traffic operations during construction X

S

e. Construction seasons X S


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Factor

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(maintenance of traffic, ease of maintenance) X

S

7. Performance of similar pavements in the area X

S

8. Availability of local materials, contractor’s capabilities, and experienced agency personnel. X

S

9. Pavement Continuity S

a. Adjacent sections X S b. Adjacent lanes X S

10. Noise issues X S 11. Subgrade soils X S 12. Climate X S 13. District or local preference S Reasoning for preference must be quantified 14. Ease of maintenance X S 15. Recycling X S

16. Conservation of materials and energy X

S

17. Stimulation of Competition S

18. Safety considerations (rutting, friction, lighting, etc) X

S

19. Smoothness


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20. Are price adjustment factors used for any materials, and if so are they used in the life cycle cost analysis. No 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) Currently investigating this issue on past projects. 22. Routine maintenance (how estimated, operations included) Since routine maintenance is such a small item, it is typically excluded in the LCCA. WSDOT intends to collect this data in the future to confirm this assumption. 23. Rehabilitation (how is timing estimated, techniques used, etc.) The Washington State Pavement Management System is utilized to determine typical pavement service life. Adjustments have made based on improved performance as a result of the use of dowel (all existing pavements were undoweled). In addition, stainless steel clad dowels being used on premium pavements. Performance of HMA is based on performance of adjacent projects. Currently the State does not require contractor QA/QC. Some Superpave. No much use of stone matrix mixes.

Salvage Value (remaining life): Used as a ratio of cost and anticipated remaining life. Residual value (recycling): Not specifically included. Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Included in estimate. Engineering and administration: Included in estimate. Flat rate for all projects. Same for HMA and PCC.

24. How are users costs weighted in relation to agency costs? Currently weighted equally. However, the analysis is summarized to show results with and without user costs. 25. Vehicle operating costs Not included. 26. User Delay Included as a function of delay due to construction.


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27. Description of the analysis process As utilized by FHWA in LCCA software. 28. Routine maintenance Crack sealing, patching 29. Preventive maintenance Chip sealing 30. What are the states standard routine and preventive maintenance operation and schedule by pavement type? There are no standards or routine schedules. 31. Allocation of resources between maintenance, rehab, new and reconstruction None 32. Do you have a formal system to track pavement condition, cost, and survivability? The Washington State Pavement Management System is used to track pavement condition and survivability. 33. Do you allow old concrete to be recycled? If so into what products? Percentage limits? Yes, everything (as long as it meets the material specifications for the product it is replacing) except new concrete pavement, hot mix asphalt pavement, and gravel backfill for dry walls. Becomes property of the contractor. Biggest difficulty is meeting LA wear specs. 34. Do you allow HMA materials to be recycled? If so into what products? Percentage limits? Yes, may be used in ballast, shoulder ballast, crushed surface, aggregate for gravel base, gravel backfill for foundations, and borrow (with some limitations) as long as the total bitumen content does not exceed 1.2 percent (or 8.0 percent in some borrow applications) and the combined material must meet the material specifications. Allowed in HMA up to 20% no new mix design required. Over 20% new mix design required.

Appendix C – Wisconsin

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Purpose The purpose of this interview is to gain insight into the following Wisconsin Department of Transportation practices:


Agency Interviewed Wisconsin DOT Hill Farms State Transportation Building 4802 Sheboygan Avenue P.O. Box 7910 Madison, WI 53707-7910 Person(s) Interviewed Name Title Phone Email Mr. Steve Krebs Chief Pavements

Engineer (608) 246-5399 [email protected]

Ms. Laura Fenley Structural ??? (608) 246-5455 [email protected] General Notes: Scot Schwandt had 95% developed a probabilistic LCCA but it never got adopted. WisDOT will go to probabilistic, but they’re waiting for FHWA guidance. WisDOT primary pavement types are conventional AC (AC over flexible base with 2 to 3:1 ratio of base/AC) and doweled JPC. Service life (i.e., time to first rehab) of AC is 18 yrs, while service life of PCC is 25 yrs. Designer can develop multiple AC and multiple PCC designs and then run them through the LCCA (up to 8 can be analyzed at a time) 1. Do you have a documented pavement type selection procedure for:

New Construction (defined as starting from a new grade): Yes. WisPave software with documented procedure (Facilities Development Manual [FDM]l, Chapter 14) Reconstruction: (defined as creation of new structure, with range being pulverization or removal of top bound layers to removal down into subgrade [incl. subgrade modification]) Yes. WisPave software and FDM Rehabilitation: Yes. WisPave software and FDM


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2. How long have you used the current type selection procedure? Current procedure has been in place for about 20 years. It has been fully automated using Visual Basic for about 3 years, and with Excel spreadsheets for about 8 years. 3. Changes made over the last 5 years? What prompted the change(s)? Some changes have been made, including automation using Visual Basic and the determination and use of hard-coded service lives. These changes were prompted by the desire for better execution and more standardization. 4. Have you used alternative bidding as a means of making a pavement type selection during the past 5 years? If yes describe the process. Was alternate bidding used on a Federal-aid project? If so, what was the basis of FHWA’s approval? No 5. Importance and extent of industry involvement in the development of type selection process? Involvement has been pretty high through the Pavement Design User Group, which consists of WisDOT engineers, consultants, and industry reps. A Pavement Policy Committee, consisting of WisDOT engineers/managers only, help guide policy changes by answering the question, “Are we making the right decision?” 6. How was the selection process implemented within the agency? Through the Facilities Development Manual (FDM). See chapter 14 of FDM. Mid 1980’s is when WisDOT began instituting LCCA, more on their own than as a result of FHWA or others. 7. How is the type selection process related to the overall project selection, budgeting, planning process used by the agency? It’s an independent process.


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8. Pavement types used for new construction or reconstruction over the last 5 years


Performance (within last 5 yrs, any early failures?)

(Good Fair Poor) Full depth ACP None None Not applicable Deep Strength ACP 190 (I-39) 30 Good ACP(less than 6”) agg base

1,700 total Good

Jointed Plain (JPCP) 214 total Good Jointed Reinforced (JRCP)

None None Not applicable


None None Not applicable


ACP: AASHTO ’72 (design life=20 yrs, estimated ESALs) PCCP: AASHTO ’72 (design life = 20 yrs, estimated ESALs)

10. What analysis period used for each pavement type? 50 years 11. Are there different foundation/base requirements for AC and PCC? WisDOT uses 2 to 3:1 ratio (base/surface) for AC pavements. Designers have flexibility to select ratio. Also, designers have a range for structural coefficients for some materials, but not others (e.g., crushed stone=0.14). Standard base requirement for PCC is 6 in. If permeable base is to be used, a 4-in drainage layer on top of a 6-in aggregate base must be specified. Subgrade improvement required based on geographical location (66% of State required to use subgrade improvement, usually a sand material). Designers are required to spec for it, unless local data show otherwise. When used, credit can be given to structure (increased k for PCC design, increased soil support value for HMAC design). Reason for the requirement is purely construction platform-related. 12. Does WisDOT use smoothness as design criteria and, if so, do they use the same initial serviceability in design? Yes, within the design equation (PSI). Initial = 4.2 for AC, 4.5 for PCC (Steve: this is absolutely backward, we only use it because that’s what ’72 Guide says to use). Same terminal values (2.5) are used for AC and PCC.


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For construction acceptance testing, California profilograph is used to measure smoothness. Typical IRI for new AC is 0.85 m/km. Typical IRI for new PCC is 1.1 m/km. Incentive is paid for smoothness (designer’s option) For in-service testing of the network, South Dakota type profiler is used to measure smoothness. 13. Typical costs and method of contract measurement

ACP in place $18 to 30/ton (depending on mix type). Cost of asphalt cement ranges from $175 to 275/ton. JPCP (slab only) $15 to 32/yd2 (this includes cost of dowels). For a 10-in JPC, typical cost is $21/yd2) JRCP (slab only) Not Applicable CRCP (slab only) Not Applicable

14. How important is first cost versus future costs? These are considered the same; one is not weighted any higher than the other. The LCCA procedure is what it is, discount rate determines relation. 15. Is life cycle cost analysis used? Yes. 16. What analysis period is used? 50 years 17. Discount Rate (how established) 5%, as dictated by Department. 5% value was developed by an economist in the old planning unit. The economist researched the discount rate to a great extent and came up with this value, which is somewhat of a social discount rate, based on resource allocation versus capital financing. No documentation of the research is available, however. 18. Initial Agency Costs – Estimating procedure WisPrice data are used. Construction costs only are used. No accounting of engineering, design, traffic control costs, etc. is made. Although traffic control costs will vary, they are too difficult to determine.


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19. How does WisDOT determine unit cost to include in the cost analysis (standardized or project by project)? Is the size of the project used in the database considered (economy of scale)? Age of the price data? How often updated? Done at the designer level, on a project-by-project basis. The size of project is considered. Price data are up to the most recent letting and are updated every month. 20. Are price adjustment factors used for any materials and, if so, are they used in the life cycle cost analysis. Yes. Fuel cost adjustment factor. There is a bid item for this. Not used in LCCA though. 21. Actual cost versus estimated cost (are completed projects evaluated for overruns etc.) All projects are evaluated for cost overruns, but overruns are not considered in pavement type selection process. 22. Routine maintenance (how estimated, operations included) Rough costs, in terms of $/lane-mi, are provided by Maintenance. Costs are a statewide number, there is no breakdown by county (note: maintenance of State highways is performed by the counties). Costs are only for mainline maintenance and they include routine activities such as crack filling and seal coating for AC, and joint resealing for PCC. 23. Rehabilitation (how is timing estimated, techniques used, etc.) Based on service life analysis (actual data). Rehab treatments are outline in FDM, but most common include conventional overlay, mill-and-overlay, and diamond grinding. Designer has the option of changing the timing of rehabs and not assigning them.

Salvage Value (prorated life or other procedure): Yes. Prorated life method. Residual value (recycling): No. WisDOT doesn’t know what they’re going to do at the end of the analysis period. Construction traffic control (crossovers, added lanes, barriers, detours, etc.): Not considered. Engineering and administration: Not considered.

Description of the analysis process: See figure 1. 24. How are user costs weighted in relation to agency costs? User costs are not considered.


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Factor

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Comments

1. Roadway/lane geometrics (lane widths, cross slopes, ability to provide drainage) No

2. Highway functional class No 3. Traffic Yes P 5 ESALs

4. Roadway peripheral features (overhead clearance, weigh-in-motion, guardrails, etc) Yes S 2

Only considered in rehab in selecting a typical strategy, such as rubblization.

5. Construction considerations a. Staging No b. Clearance for equipment No c. Construction operations No? Only In weird situations.

d. Traffic operations during construction No e. Construction seasons No


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Factor

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(maintenance of traffic, ease of maintenance) Yes S 3 Sometimes considered, based on who is the maintaining authority of the roadway.

7. Performance of similar pavements in the area Yes S Statewide it is considered in the service life. It is not considered locally.

8. Availability of local materials, contractor’s capabilities, and experienced agency personnel. No?

Not a direct consideration. Availability of materials would only affect the unit prices of the material.

9. Pavement Continuity a. Adjacent sections Yes P 4 More commonly adjacent sections than adjacent lanes. b. Adjacent lanes Yes P 4

10. Noise issues Yes S 2 Sometimes considered, but it is not a selection factor---WisDOT builds quiet pavements.

11. Subgrade soils Yes P 5 12. Climate No

13. District or local preference Yes S 3 Only as related to maintenance, never district preference (has to fall within the 5% cost difference category)

14. Ease of maintenance Yes S 3 Only as related to maintenance, never a district preference (has to fall within the 5% cost difference category)

15. Recycling No

16. Conservation of materials and energy No

17. Stimulation of Competition No

18. Safety considerations (rutting, friction, lighting, etc) Yes? S 1 Potentially for rehabs, but not for new construction.

19. Smoothness No Considered in design, but doesn’t determine which pavement type.


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Figure 1. Diagram of WisDOT pavement type selection process.

1972 AASHTO Design Guide (WisPave AC & PCC Modules) (Inputs: soils, traffic, serviceability, mix parameters, etc.)

Determine Equivalent Sections (generally 2, but up to 8)

Determine SN

LCCA (WisPave LCCA Module) 5% discount rate, 50-year analysis period

Design Criteria Adjustments

Thickness determined at District level

Deterministic LCCA Results

Agency Cost Inputs (using WisPrice or other) Construction unit costs

Rehab unit costs Maint costs ($/lane mi)

Performance Inputs (hard-coded service lives)

Initial Structure Rehabs

Selected Pavement Type

Peer Review for discussion as to reasons

for higher costs.

Cost Difference > 5%

Cost Difference <= 5%


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25. Vehicle operating costs User costs are not considered. 26. User Delay User costs are not considered. 27. Description of the analysis process User costs are not considered. 28. Routine maintenance Routine and preventive maintenance of the mainline only are combined into one statewide cost. Maintenance includes crack sealing, patching, seal coating, joint resealing. 29. Preventive maintenance See response above. 30. What is WisDOT’s standard routine and preventive maintenance operation and schedule by pavement type? Maintenance for new AC and AC overlays): Crack seal at 3 years, seal coat at 8 years Maintenance for PCC: Joint reseal at 10 and 15 years. 31. Allocation of resources between maintenance, rehab, new and reconstruction Not determined by Pavement Mgt group. Not sure how this plays into the selection process. Department can investigate this a little further. 32. Does WisDOT have a formal system to track pavement condition, cost, and survivability? Pavement Conditions: Tracked through pavement monitoring and the Pavement Management System database. South Dakota profiler is used. Each section is surveyed every other year. Pavement Costs: Proposal Management group (outside of WisDOT) provides Department with cost data for use in WisPrice. WisPave includes ability to filter projects according to size, location, etc. It is based on 3 lowest prices for each bid item for each project. Survival is evaluated.


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33. Does WisDOT allow old concrete to be recycled? If so into what products? Percentage limits? Some of this is done, goes into unbound layers and into new PCC. Vast majority is for unbound. 34. Does WisDOT allow HMA materials to be recycled? If so into what products? Percentage limits? This is done, goes into unbound layers and into new AC. Vast majority is going back into unbound.

Appendix D

Comparison of State Pavement Practices

Appendix D

D-1

Feature

Ohi

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Illin

ois

Indi

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Mic

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Documented Type Selection

New Construction X X X X 7 X X X X X X X Reconstruction X X X X 7 X X X X X X X Rehabilitation X X X X X X X Time Used 6 months > 10 years 23 >10 years 6 months 3 years 6 years 4 years 5 years 18 years 15 yr 20 yr Modified last 5 years? Yes Minor No Yes Yes Yes Minor Yes Yes Prob.

Analysis Yes

Modifications underway Yes Yes Yes Yes No Yes Yes Yes Yes Yes No Extent Industry Involvement Input &

review

Input and Review during development

Review Review Yes, ad

hoc committee

Non-voting Minor Partici-pant Review Review

Significant (via PD

User Group)

How implemented Issued by Depart-

ment Design Manual Design

Manual Design Manual

Design Manual

Commissioner Issues

Design Manual

Design Manual

Design Manual Directive

Facilities Development Manual

Alternate bidding used Consider-ing No No 1 proj. 8 2 proj. No No 1 proj.

1 Pilot Project

Proposed No No

Pavement Types used HMA-Full depth No Yes Yes No No No No <1% Yes No No HMA-Deep Strength Yes No Yes Yes Yes Yes 90% 95% No Yes Yes PCC-JPCP Yes Yes Yes Yes Yes 12 Yes 10% <5% Yes Yes Yes PCC-CRCP No Yes No No No No No No No No No Design Procedure HMA thickness design AASHTO

93 M-E 24 AASHTO 93

AASHTO 93

AASHTO 93

Modified AASHTO

Modified AASHTO

93

Modified AASHTO

93

AASHTO 93

AASHTO 93

AASHTO '72

Traffic Design Life 20 20 20 15 20 20 50 20 20 40 20 "a" bituminous surface 0.35 n/a 0.34 0.44 0.42 n/a 0.42 0.42 0.44 0.44 0.44 "a" bituminous intermediate layer 0.35 n/a 0.36 0.40 0.36 n/a 0.42 0.42 0.44 0.44 0.44

"a" bituminous base 0.35 n/a 0.34 0.25 0.36 n/a 0.42 0.42 0.40 0.30 0.34 PCC thickness design AASHTO

93 M-E 24 AASHTO 93

AASHTO 93

AASHTO 93 AASHTO 86

Modified AASHTO

93

Modified AASHTO

93

AASHTO 93

AASHTO 93

AASHTO '72

Traffic Design Life 20 20 30 25 20 35 50 30 20 40 20

Appendix D

D-2

Feature

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PCC Mr (S'c) 700 650 25 652 700 670 675 650 725 20 631 20 650 650 PCC Ec 5,000,000 n/a 3,408,390 5,000,000 4,200,000 4,000,000 4,350,000 4,000,000 4,000,000 4,200,000 Are foundation requirements for HMA and PCC the same

Yes Yes Yes Yes No 13 No Yes Yes No same subgrade Yes

Is initial serviceability same for PCC and HMA

4.2 PCC 4.5 HMA N/A Yes 4.5 PCC

4.2 HMA Yes n/a n/a Yes 4.5 PCC 4.2 HMA Yes No

Method of Payment HMA Ton (produced) X X X X metric metric X 32 X X Sq. yd. (measured thickness) X X 32

Cu. Yd. (measured) X PCC Sq. yd. (design thickness) X X X X X X 5 X X X Cu. Yd. (design thickness) X 5 cu. meter Cu. Yd. (measured thickness) X 6

Liquid AC Price Adjustment Yes No No Yes No No Yes Yes Yes No Yes

Economic Analysis Use LCCA Modified

21 Yes 26 Yes Yes Yes EUAC Yes Yes Yes Yes Yes Yes

Analysis period 35 40 40 40 Varies 14 35 50 new 30 rehab

50 new 30 rehab 40 60 50

Discount rate OMB A94 3 4 4 OMB A94 4.5 9 OMB A94 5.3 11 6 4 5 19

Sensitivity Analysis No No 0 to 10 3 to 5 No No No 2% No 2-5 Prob No Initial Cost Centrally developed cost data for LCCA Yes Yes No Yes Yes No No No No No No

Project Specific (discretionary adjustment) No No Yes No geographi

c area Yes 10 Yes Yes Yes Yes Yes

Adjust LCCA for as built quantities No No No No No No No No No No No

Appendix D

D-3

Feature

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Routine Annual Maintenance Costs ($/lane-mile)

No Yes 27 No No No No No No Yes No No

Scheduled Maintenance Costs No Yes Yes No Yes Yes Yes Yes Yes No Yes

How estimated n/a Committee MM system n/a Past

History Committee Best Est. Best Est. MM system n/a MM

system Rehabilitation (overlay, CPR, etc.) Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes

How estimated Best Est. Best Est. PM sys PM sys PM & MM Best Est. Best Est. Best Est. PM sys PM sys PM sys HMA Year at 1st Rehabilitation for LCCA 12

Function of traffic - 4

categories (see detailed

schedule)

project specific

project specific 10 22 15 15 19 10 15 18

Year at 2nd Rehabilitation for LCCA 22

Function of traffic - 4

categories (see detailed

schedule)

project specific

project specific 13 22 27 27 31 20 30 project

specific

PCC Year at 1st Rehabilitation for LCCA 22 20 (CPR) 28 project

specific project specific 9 22 17 15 18 20 20 25

Year at 2nd Rehabilitation for LCCA 32 None to

reconstruction project specific

project specific 15 22 27 30 28 30 40 project

specific

Residual Value No No No No No No No No No No No Salvage Value No No Rem life Rem life No 15 No Rem Life Rem Life No Rem Life Rem Life Construction Traffic Control

Initial construction No No No Yes No Yes No No No Yes No Rehabilitation Yes No No No Yes No No No Yes Yes No Engineering and Administration

Initial construction No No No No No No No No No Yes No Rehabilitation Yes No No No Yes No 27% No No Yes No

Appendix D

D-4

Feature

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User Costs Delay Indirectly No No Yes

FHWA Yes U of

Mich Future Future Future Yes Yes No

VOC (roughness, tire wear, rolling resistance, etc.)

No No No No No No Future Future No No No

Are user costs include in LCCA No No No Yes Yes No Future Future Yes Yes No

Spread of LCCA considered equal

0 to 3 Init 0 to 10

fut. 10% 10% 10% 0% 0% 0% 0% 10% 15% 5%

Recycling PCC No Yes Yes no recent

projects Yes 16 Yes Yes Yes Yes Yes Yes, some

Uses n/a

Capping, Subbase, Concrete,

Shoulder, Fill

Subbase granular materials

base, subbase

base, subbase

base, subbase

typically used as

backfill for structures

granular materials

unbound base

(most) PCC (very

little) HMA Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Uses

HMA Capping, Binder,

Shoulder, Fill HMA HMA HMA 17 HMA HMA HMA HMA HMA unbound

base, HMA

Max % in Wearing Course 20 1 30 29 25 2 15 14 18 30 3 20 10 to 30 5 - 15 30 20 4 20 31

Max % in Intermediate Course 35 1 30 29 25 2 28 18 50 3 20 10 to 30 5 - 15 30 20 4 35 31

Max % in Bituminous Base 35 1 30 29 25 2 25 28 18 50 3 30 30 5 - 15 30 20 4 35 31

Appendix D

D-5

Table Notes 1. Whenever more than 10% of reclaimed asphalt concrete pavement is used it must be included in the mix design to

establish the job mix formula and conform to the requirements of the specified asphalt binder for the asphalt binder proposed for use in the mixture, by the combination of reclaimed asphalt, virgin asphalt, and rejuvenating agents. A maximum of 10% RAP is allowed in polymer modified surface mixtures.

2. Up to 15% use grade of asphalt binder specified for the project. 15% to 25% asphalt softer required 3. Subject to meeting mix design requirements 4. Up to 20% no new mix design, over 20% required a new mix design 5. Two pay items for PCC sq. yd and cu. yd. the cu. yd. quantity is base on planned thickness 6. Quantity is based on cored thickness up to 0.5 in over planned thickness 7. Maryland is currently operating under an interim procedure that has not been formally issued and has not been

published. 8. Maryland did one alternate bid project under FHWA SEP-14 9. Currently 4.5% but going to OMB -A94 10. Not unit cost based. Develop costs based on materials and construction costs at the specific site. Features for premium

enhanced designs are included after pavement type has been selected and are not included in the LCCA analysis 11. Ministry of Finance social discount rate. They suggest a s percent sensitivity level 12. Also still build some JRCP 13. Greater sand subgrade depth required for HMA, for frost protection 14. 26 years for new high-volume PCC and HMA, 21 years for unbonded PCC, 20 years for HMA on rubbilized 15. Analysis period selected to coincide with the end of the pavements service life 16. Must meet specification requirements for material being used as. Material becomes property of contractor and is

generally used in non-state funded commercial work 17. Material becomes property of contractor and is generally used in non-state funded commercial work 18. Percentage is by weight of total binder in the mix. Above 17% binder grade adjustments required 19. WisDOT policy set by economist in Planning a long time ago. Rate is somewhat of a social discount rate. 20. Flexural strength based on actual field data. 21. First and future costs have separate weightings. 22. Strategies reflect the overall maintenance approach that has been used network wide for a specific fix based on

historical maintenance and pavement management records 23: Some sort of type selection process has been in place in Illinois since the mid-70s; the latest revision is more than 10

years old. 24 For new and reconstructed JPCP and Full-depth pavements which enter the LCCA stream, M-E design is used.

However for JRCP and CRCP, modified AASHTO procedures are used. Same is true of composite pavements and certain cross-sections widened and resurfaced with HMA.

25: Center-point loading at 14 days. 26: Only for Full-depth HMA and JPCP 27: Fixed cost and includes striping, lane delineators, reflectors, etc. 28: There are 7 rehabilitation activities in the life cycle including patching and sealing. Quantities are specified in

detailed schedule. Shown here is the time to major activity. 29: The maximum percentage of rap is a function of mix design and ranges from 0 percent for an Ndesign of 105 to 30

percent for an Ndesign of 30 and is not allowed in polymer modified mixes. 30. For mixtures with more than 15 percent RAP, the department evaluates the asphalt cement content of the RAP source

material and determines the grade of the asphalt cement and recycling agent the contractor will be required to use in the final mixture. When RAP is used, a plan to control RAP and procedures to handle the RAP of different compositions must be developed and provided to the department.

31. Combined RAP and virgin aggregate shall meet percent crushed and natural sand quality requirements. The blend of new asphaltic material with extracted RAP asphaltic material shall meet the penetration or viscosity requirements for the specified asphaltic material.

32. Payment is based on square yards for most projects. Tonnage is only used on very small projects and for leveling courses.

Appendix E Concepts for Development of Survival Curves

and Procedures for Adjustment of Survival Curves to Account for New Technology

Appendix E

E-1

Concepts for Development of Survival Curves and Procedures for Adjustment

of Survival Curves to Account for New Technology

Harold L. Von Quintus, P.E., Michael I. Darter, P.E., John Hallin, P.E., & David K. Hein December 9, 2003

Introduction Survival curves have been developed and used by various agencies to determine the expected service life of previously built designs and materials for use in LCCA and for other management purposes. Survival curves are uniquely useful to LCCA because every point on the curve represents the probability that a given pavement section will be rehabilitated (or reach a given critical condition level). Thus, the time in years when the probability equals 0.50 (or 50 percent) is the age used in LCCA pavement life projections. The Illinois DOT (1, 2) and the Ontario Ministry of Transportation (3, 4, 7) recently sponsored studies that utilized survival curves. The procedures utilized in these studies are generally recommended for use. These curves can be developed for various original pavements (e.g., deep strength flexible, full depth flexible, jointed plain and jointed reinforced concrete pavement) and for all types of rehabilitations (e.g., thin HMA overlays, thick HMA overlays, unbonded PCC overlay, diamond grinding restoration). The paving industries have sponsored the developed survival curves for various highway networks, including corridors (such as a 100-mile corridor), and even for specific counties. This document briefly describes the development of survival curves that can be used in developing the expected service life of pavement design and rehabilitation strategies appropriate for use in LCCA. It also provides very preliminary concepts to modify these survival curves based on new design procedures or new materials/design features that are not available in the existing historical databases. Development of Survival Curves Survival analyses—also called probability of failure analyses—have been used for decades in actuarial sciences. They have also been used in the pavement industry for many years. Survival analysis is a statistical method for determining the distribution of lives, as well as the “life expectancy,” of a subset of pavements. Since not all of the pavements included in the analysis have reached the end of their service life, the mean of all sections ages cannot be used. The life expectancy and probability of failure are computed considering all sections in the subset using statistical techniques such as the PC SAS LIFETEST procedure. Survival curves have been used to compare the mean and standard deviation of the expected service life for different design features and site factors in evaluating the adequacy of the design procedure.

Appendix E

E-2

Survival curves are typically based on age but can also be based on traffic loadings (ESALs). The age or ESALs at “failure” must be based on a clearly defined condition, such as the age or ESALs at major rehabilitation (overlay, reconstruction) or at a specific pavement condition (such as PCI =65). The Illinois and Ontario survival curves are based on both age and ESALs, which consider different survival aspects of these pavements. Together, these survival curves tell a more complete story about how the pavements performed. The Illinois curves are based on a definition of failure as when rehabilitation is actually placed. Ontario curves are based on a definition of failure as when a certain Pavement Condition Index (PCI) is achieved. Illinois survival curves for one family of pavement are shown in figure E-1 for both age and traffic. Care must be taken when inferring results from survival curves because they directly represent the population of pavements they are based on. For example, if the 50th percentile life is 15 years, and these pavements were designed for 20 years, it does not necessarily follow that they did not perform as designed because traffic may have been much higher than planned for most of the sections included in the survival analysis. Thus, the traffic survival curves are important to determine the traffic that these sections have been subjected to during their lifetime, which may be two to four times greater than design traffic. So both survival curves are needed to tell the complete story. Mathematical models are best fitted to the points in the survival curves to predict the probability of survival or failure as a function of age or cumulative ESALs. The general form of these models is as follows:

de

acAgeb

++

=− )(*1

Failure ofy Probabilit Eq. E-1

de

acESALb

++

=− )(*1

Failure ofy Probabilit Eq. E-2

Where: Failure = existing pavement is overlaid or reconstructed Age = number of years since construction (new pavement or overlay)

ESAL = cumulative equivalent single axle loads since construction (new pavement or overlay), millions

a, b, c, d = regression coefficients determined from analysis Of course, the probability of survival is 1 minus the probability of failure. Optimization was used to determine the regression coefficients that best fit the survival points to the above models for each type of pavement and overlay of interest.

Appendix E

E-3

A. Age survival curves

B. ESAL survival curves

Figure E-1. Age and ESAL survival curves for HMAC in the northern Illinois.

0

10

20

30

40

50

60

70

80

90

100

0 5 10 15 20 25 30

Age, years

Prob

abili

ty

of F

ailu

re, %

HMAC - North

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12

Cumulative ESALs, million

Prob

abili

ty

of F

ailu

re, %

HMAC - North

Appendix E

E-4

It is important to note that survival curves for pavements are necessarily based on previously built designs, materials, construction, and maintenance. The data used to develop the survival rates or probability of failure curves are those included in pavement management databases and represents typical construction, material specifications, mixture designs, and structural cross sections that have been designed and built by the agency within the past time period represented by the data. These can be called “benchmark” survival curves. It is often the case that many if not most of the pavements included in an agency’s pavement management system database are no longer constructed by the agency due to poor performance. The next section of this document presents some preliminary concepts on how to adjust benchmark survival curves. Two methods are described to adjust benchmark survival curves to reflect new technology in improved pavement designs and rehabilitations. The performance of these improved pavements is of course not available in the historical databases. Modification of Survival Curves for New Conditions and Materials Within the past decade, there have been major changes in the methods used by agencies to design, build, and maintain pavements. Many agencies have just implemented some of these new technologies, such as the Performance Graded (PG) binder specification, SMA, jointed plain concrete pavements with dowels (JPCP), subdrainage layers, and others. Technical progress thus creates problems in that the survival curves based on “old” pavement technology may not be the same as survival curves based on “new” technology. But there are no or little physical data from “new” pavement projects to develop “new” curves. This will always be the case as technology continues to develop over time. The existing survival curves must be adjusted to fit the new technology more closely before they can be used in LCCA. Most agencies agree that the survival curve and mean expected service life need to be adjusted due to improvements in design and materials and construction. However, there is no accepted or standard procedure that has been published for adjusting historically based survival curves. The only known significant work of this kind was performed for the Ontario Ministry of Transportation (4, 7). This work utilized a panel of agency and industry experts to provide subjective input on the impact of the technological improvements and resulted in a small “shift” of a couple of years in the 50 percentile life. The reason for the small shifts were the clear recognition that many factors cause the deterioration of pavements and no single improvement in technology will shift the 50 percentile life by a large amount.

Appendix E

E-5

Practical Adjustment of Survival or Probability of Failure Curves It is critical to define the reasons for the spread in survival shown in figure E-1. Why do some pavements fail early and some later on? The answer is that there are many causes of mechanisms that lead to failure, and any population of pavements exhibits deterioration from many causes and mechanisms. Major causes include the following:

• Construction quality (e.g., compaction of unbound materials, thickness of layers, placement of dowels in JPCP, HMA air content).

• Design quality (e.g., HMA thickness, JPCP joint spacing, traffic loadings, subgrade support).

• Materials quality (e.g., durability to climatic factors like freeze-thaw, chemical attack). • Maintenance quality (e.g., cleaning/clogging of subdrainage outlets).

Variations of each of these factors can result in shortening or lengthening of the time when different distress types and smoothness becomes significant, causing a need for rehabilitation and thus contributing to the spread of the survival curve. In addition, there is always “random variation” in fatigue life (of replicate sections) due to unknown causes that will cause some spread of the survival curve for all pavement types. Therefore, if a given design deficiency was addressed, this would have an impact on the survival curve but not as great as might be expected because there are so many other factors that affect performance that would not be affected. The use of data from limited test sections must be carefully considered. For example, assume an experimental site that contained two test sections. Test section B (new design) performed 50% longer than section A (conventional or old design). This would not shift the overall population survival curve representing these designs by a factor of 50%. The true shift in survival curve would be far less than 50% because many other factors affect the life of pavement sections. This can be illustrated by the example that follows for conventional HMA pavements. For the example, let us assume that the pavement management database was used to determine the number of projects within each age category and the types of distress that exceeded the critical levels of the distress, requiring some type of rehabilitation. Table E-1 shows the major types of distress over the design analysis period. Within each cell is the estimated percentage of total failure that each contributes to HMA rehabilitation for that age group. The type of rehabilitation will vary by distress, however, for this example the type of rehabilitation is not considered. For this example, it is assumed that the agency is considering adopting the Performance Grade (PG) binder specification to minimize the number of projects with early or premature rutting and thermal cracking. The PG binder specification has been found to eliminate early rutting caused by inferior binder properties on the high temperature side and eliminate early thermal cracking caused by inferior binder properties on the low temperature side. For the data, we will make the following assumptions.

Appendix E

E-6

• Half of the projects with premature rutting are caused by inferior materials and the other

half are caused by inadequate construction procedures. Use of the PG binder specification will have no effect or impact on the inferior construction practices.

• Two-thirds of the projects with premature transverse cracking are caused by inferior materials or binder properties on the cold side, while one-third of the projects are caused by inadequate construction. The number of projects that are expected to exhibit transverse cracking for service lives greater than 20 years are not affected by the PG binder specification.

Table E-1. Number of projects by distress type that exceed the critical levels of distress causing

rehabilitation (note, the numbers are fictitious, shown for illustration only).

Age of Pavement, years Distress Type & Causes of Failure 0 to 5 5 to 10 10 to 15 15 to 20 20 to 30Total Number of Projects in Each Age Category 90 75 60 45 30

Rutting Inferior Materials & Construction 4 2 1 1 0

Bleeding Inadequate Mix & Construction 1 1 0 0 0

Transverse Cracking Inferior Materials 3 2 2 3 3

Raveling Inadequate Construction 1 1 2 2 2

Bottom-Up Cracking

Inadequate Thickness 0 1 3 4 4

Top-Down Cracking

Inadequate Mix Properties 0 1 2 2 2

Edge Cracking, LCNWP Expansive Soils 0 1 2 1 1

Block Cracking

Climate & Inadequate Mix 0 0 2 3 3

Smoothness Distress & Inferior Construction 1 1 3 2 4

Total Number of Failed Projects 10 10 17 18 19 Probability of Failure, % 11.1 23.5 46.5 67.1 87.1

Appendix E

E-7

Given the above assumptions, new design strategy A in table E-2 summarizes the number of projects that are expected to exhibit high levels of distress given the use of the PG binder specification to improve the performance of HMA mixtures and pavements. New design strategy B in table E-2 summarizes the number of projects that are expected to exhibit high levels of distress with the assumption that the agency adopts the PG binder specification and perpetual pavement concept. For the projects shown in column B, it was assumed that the perpetual pavement concept will eliminate the bottom-up fatigue cracks but not the surface-initiated cracks. Thus, the number of these projects was reduced to zero. Table E-2. Projects that exceed the critical levels of distress, causing rehabilitation (numbers are

fictitious, shown for illustration only).

Age Category, years Distress 0 to 5 5 to 10 10 to 15 15 to 20 20 to 30 Number of Projects 90 75 60 45 30

New Design Strategy A B A B A B A B A B

Rutting 2 2 1 1 0 0 0 0 0 0 Bleeding 1 1 1 1 0 0 0 0 0 0 Transverse Cracking 1 1 0 0 0 0 1 1 3 3

Raveling 1 1 1 1 2 2 2 2 2 2 Bottom-Up Cracking 0 0 1 0 3 0 4 0 4 0

Top-Down Cracking 0 0 1 1 2 2 2 2 2 2

Edge Cracking 0 0 1 1 2 2 1 1 1 1 Block Cracking 0 0 0 0 2 2 3 3 3 3 Smoothness 1 1 1 1 3 3 2 2 4 4 Total Number of Failed Projects 6 6 7 6 14 11 15 11 19 15

Probability of Failure, % 6.7 6.7 16.0 14.8 37.0 31.9 58.3 50.0 84.7 76.6

Appendix E

E-8

Figure E-2 graphically illustrates the increase in expected service life for the example assuming that the agency adopts the PG binder specification and perpetual pavement concept given the other types of distress are found that occur on the highway network from the pavement management database. The mid-range of each age group was used in the example for simplicity.

0102030405060708090

100

0 10 20 30

Age, years

Prob

abili

ty o

f Fai

lure

, %

Old Spec.

PG Binder Spec.

PG & Perp. Pavt.Spec.

Figure E-2. Increase in expected service life for using new technology based on the types of distress that typically occur on the highway network (numbers are

fictitious, shown for illustration only). As shown in figure E-2, the 50 percentile expected service life prior to rehabilitation for the three conditions is about 13 years for the old specifications and design method, 15.5 years after adopting the PG binder specification, and 17.5 years after adopting the PG binder specification and perpetual pavement design method. Please note that these values are fictitious and shown only for illustration. Note that a similar example could be created for rigid pavements. The point of this illustration is that the improvement of some aspect of design, construction, materials, and rehabilitation will certainly shift the survival curve for the pavement type under consideration, but the shift will not be that much because other factors affect performance and life.

Appendix E

E-9

Theoretical Adjustment of Survival or Probability of Failure Curves The reliability of a pavement depends on the length of time it has been in service and design features and site factors that are not properly accounted for in a thickness design procedure. Thus, the distribution of the time to failure of a pavement type is of fundamental importance in reliability studies. A method used to characterize this distribution is the failure rate. The failure rate can be defined as follows.

If f(t) is the probability density of the time to failure of a given pavement type and design strategy, that is, the probability that the pavement will fail between times t and t+∆t is given by f(t)*∆t, then the probability that the pavement will fail on the interval from 0 to t is given by:

( )∫=

tdxxftF

0)( Eq. E-3

The reliability function, expressing the probability that it survives to time t, is given by:

( ) ( )tFtR −= 1 Eq. E-4

Thus, the probability that the pavement will fail in the interval from t to t+∆t is F(t+∆t)-F(t), and the conditional probability of failure in this interval, given that the pavement survived to time t, is expressed by:

( ) ( )( )tR

tFttF −∆+ Eq. E-5

Dividing by ∆t, one can obtain the average rate of failure in the interval from t to t+∆t, given that the pavement survived to time t:

( ) ( )( )

∆

−∆+tRt

tFttF 1 Eq. E-6

For small ∆t, one can get the failure rate, which is:

( ) ( )( )

( )( )tF

tftRtf

tZ−

==1

Eq. E-7

The failure rate is expressed in terms of the distribution of failure times. A typical failure rate curve is composed of three parts or can be grouped into three areas, as shown in figure E-3 and defined below.

Appendix E

E-10

00.05

0.10.15

0.20.25

0.30.35

0.40.45

0 10 20 30

Age of Pavement, years

Failu

re R

ate

Figure E-3. Typical failure rate relationship for pavement structures.

1. The first part is characterized by a decreasing failure rate with time and is representative of the time period during which early failure or premature failures occur. This area or time typically represents pavements that were inadequately designed or built, using inferior materials.

2. The second part is characterized by a constant failure rate. A constant failure rate represents the time period when chance failures occur, or the failures occur at random with pavement age. In some survival methods, this area is referred to as the useful life of a pavement.

3. The third part is characterized by an increasing failure rate with time. This area or time represents the reverse of the first part, and when failure is a result of multi-distresses as related to a combination of parameters over time. As an example, exponential growth increases in traffic, past the design period from which thickness was determined.

The failure rate can be determined by organizing the performance data in terms of the distribution of pavement age exceeding a critical level (failure) versus the distribution of age for those pavements exhibiting a value lower than the critical value. Figure E-4 shows a typical probability of failure relationship from actual data included in the Long Term Pavement Performance (LTPP) database for International Roughness Index (IRI) values measured on flexible pavements in the GPS-1 and GPS-2 experiments.

Premature Failure Part

Chance Failure Part

Wear Out Failure Part

Appendix E

E-11

Figure E-4. Survival analysis or probability of exceeding a critical roughness magnitude. Given the above definition of each parts of the probability of failure relationship with time, the failure rate can be defined as:

( ) ( ) ( )

∫=−

tdxtZ

etZtf 0 Eq. E-8

Assuming that the failure rate is constant within the second part and replacing Z(t) with α , the distribution of failure times is an exponential distribution as shown below. ( ) [ ]tetf αα −= Eq. E-9 Many survival curves, or conversely the probability of failure, are based on the above relationships and assumptions. Unfortunately, the failure rate within the second part is not usually constant, and the failure rates for the first and third parts are not inversely proportional to one another. For these cases, which are typical for pavements, the failure rate can be estimated by the following relationship. ( ) 1−= βαβttZ Eq. E-10 Thus, ( ) [ ]βαβαβ tettf −−= 1 Eq. E-11

Survivability Analysis for Roughness; Probability of Exceeding Critical Value

0

20

40

60

80

100

120

0 10 20 30 40

Age, year

Prob

abili

ty o

f Exc

eedi

ng

Rou

ghne

ss L

evel

, %

Low Roughness, >1.5 m/km

Moderate Roughness, >2.0m/kmExcessive Roughness, >2.5m/km

Appendix E

E-12

This density function is termed the Weibull distribution, and it is typically used in failure analyses. Use of the Weibull distribution permits the adjustment of the probability of failure based on new technologies and materials. This adjustment procedure is discussed below and is based on limited testing or evaluation of the new technologies and materials. Adjustment of Survival Curves The following provides concepts for adjusting survival curves to account for the use of new technologies and materials in life cycle cost analysis. The process assumes that the survival curve or probability of failure curve has been developed from actual performance data included in historical databases using traditional design procedures and materials, as shown in figure E-4. This process also assumes that limited laboratory and field testing is performed on the materials and pavement structures, and limited performance data is available from other sources. As noted above, parameters α and β of the Weibull distribution (see equation E-11) can be determined from existing data and then adjusted to account for the use of newer technologies and materials, similar to the example provided in the practical adjustment of the survival curves.

• Step 1—Separate the probability of failure curve into the three parts. Each part is handled separately in making adjustments to the relationship. In addition, each part of the curve will need to be assigned a specific type of distress that controls the failure definition. For example, the premature failures might be more related to rutting or thermal cracking for the first part, while fatigue cracking, smoothness, and/or PCI might be controlling the second part, and fatigue cracking or durability type distresses controlling the third part. This would be agency dependent, highway functional classification dependent, or other factors that existing technology does not properly consider.

• Step 2—Determine the adjustment that is to be made to the first part of the survival

curve. These can be based on limited torture testing in the laboratory and on limited accelerated pavement testing. For this step, results from torture testing and accelerated pavement testing for conventional structures and materials are compared to those built or designed using the new technology. This testing comparison is used to determine the increase in age or time to reach the constant or uniform rate of increase in failures. This is just an adjustment in magnitude of age or shifting of the first part of the curve—the rate of change is not varied. The reason for this direct shift in age is that most of the premature failures are not dependent on time, but on other random factors that the existing technology does not consider. The new technology is assumed to adequately account for at least some of these random factors. The torture and accelerated pavement testing are used to confirm or validate that hypothesis and its magnitude.

Appendix E

E-13

• Step 3—Determine the adjustment that is to be made to the second part of the survival

curve. This adjustment can be based on limited accelerated pavement testing and long-term field studies of the new technology used for other site factors (different climate, foundations, etc.). For this step, the accelerated pavement testing would compare the conventional structures and materials to those built or designed using the new technology and the longer-term field comparisons can be obtained from the literature and other databases. This testing comparison is used to determine any change in the rate of failure with age or time. In other words, the adjustment in magnitude of age can be time dependent—the exponent of equation E-11. The reason for this time-dependent shift in age is that the new technology may affect the slope of the chance failures, as well as a direct shift in the magnitude of age or time. The type of adjustment is dependent on whether the new technology is just materials or mixture design related with no change in the structural design procedure or a combination of both. This adjustment is more dependent on using engineering judgment because of the longer-term projections of failure and its definition.

• Step 4—Determine the adjustment that is to be made to the third part of the survival

curve. This part of the curve is usually not adjusted but assumed to be the same as for the initial data. The shift is simply that part defined from the end of the second part. The reason for keeping this part of the curve the same is that longer-term predictions should only be accounted for with actual data. Thus, this part should only be adjusted when actual data become available.

• Step 5—Using the adjustments determined from Steps 2 and 3, calculate the new

probability of failure relationship. This relationship should then be compared to the one developed from historical data to ensure engineering reasonableness.

• Step 6—The mean and standard deviation for the expected service life can then be

determined for use in LCCA. Summary While it is very important to develop an initial set of survival curves for a given pavement “family,” it is equally important to realize that this curve represents that population of pavements with its specific traffic, climate, design, materials, construction, and maintenance. This survival curve could be thought of as a benchmark curve.

Appendix E

E-14

As is normally the case, the highway agency has made many improvements to that “family” of pavements over the past several years, and the use of the benchmark survival curve may not be reasonable. An adjustment to this curve can be made to reflect the new technology improvements to design, construction, materials, and maintenance. This adjustment must consider the impact of the new technology to all types of failure mechanisms (distress, smoothness, etc.). The overall impact to the population of pavements built with this new technology will be to shift the survival curve to a longer life and perhaps also traffic carrying capacity but this shift will not be great because of so many factors that affect pavement performance. This topic is an area of very little research and much remains to be discovered to develop a reliable procedure to shift survival curve due to new technologies. References 1. N.G. Gharaibeh and M.I. Darter, Longevity of Highway Pavements In Illinois—2000 Update,

Final Report FHWA-IL-UI-283, Illinois Department of Transportation, Springfield, Illinois, 2002.

2. N. G. Gharaibeh and M. I. Darter, Probabilistic Analysis of Highway Pavement Life for Illinois, Transportation Research Record 1823, Transportation Research Board, Washington, D.C., 2003.

3. K.L. Smith, N.G. Gharaibeh, M.I. Darter, H.L. Von Quintus, B. Killingsworth, R. Barton, and K. Kobia, “Review of Life Cycle Costing Analysis Procedures” (in Ontario), Final Report prepared for the Ministry of Transportation of Ontario, Toronto, Ontario, Canada, 1998.

4. A. Bradbury, T. Kazmierowski, K.L. Smith, and H.L. Von Quintus, “Life Cycle Costing of Freeway Pavements in Ontario,” paper presented at the 79th Annual Meeting of the Transportation Research Board, Washington, D.C., 2000.

5. American Association of State Highway and Transportation Officials, AASHTO Guide for Design of Pavement Structures, Washington, D.C., 1993.

6. J. Walls, III, and Michael R. Smith, Life-Cycle Cost Analysis in Pavement Design Interim Technical Bulletin, FHWA-SA-98-079, Washington, D.C., 1998.

7. Hein, D.K., J.J. Hajek, K.L. Smith, M.I. Darter, S. Rao, B. Killingsworth, and H. Von Quintus, “The Benefits of New Technologies and Their Impact on Life-Cycle Models,” Final Report, Ministry of Transportation of Ontario, December, 2000.

Appendix F Meeting Facilitator

Scope of Work

Appendix F

F-1

Meeting Facilitator Scope of Work

General The Ohio Department of Transportation (ODOT) is requesting letters of interest (LOI’s) from qualified individuals to serve as a meeting facilitator. For purposes of this LOI, a facilitator is described as an individual who provides impartial management of meetings designed to enable participants with divergent views to focus on substantive issues and reach a common understanding of these issues. The facilitator will assist in developing an agenda for each meeting, assist in determining the appropriate length of the meeting, enforce ground rules of conduct, promote interaction and communication during meetings, and bring issues to closure. The facilitator will remain neutral relative to the content of the meeting in that they will not take sides or express a point of view during the meeting. The individual selected will be asked to facilitate a series of meetings between ODOT and representatives of the portland cement concrete pavement and asphalt pavement construction industries. While ODOT has the responsibility of developing and implementing pavement selection, design, and specifications for construction and materials it is their desire to obtain the views of industry before making decisions. Conversely ODOT wishes to insure that industry understands the reasoning and support behind their decision making process. The facilitator should be aware that there is a spirited level of competition between the asphalt and concrete paving industries. Both industries closely guard their existing market share and are always endeavoring to increase market share. This spirit of competition spilled into the political arena in 2003 with a legislative mandate that ODOT hire a neutral third party (NTP) to evaluate their pavement selection procedures. The nature and type of issues raised during the NTP’s interviews with the paving industry, led to the NTP recommending that ODOT conduct a series of facilitated meetings with members of the paving industries. Schedule Approximately six 1- or 2-day meetings will be scheduled during a 12-month period commencing with the selection of the facilitator. All meetings will be held at the ODOT headquarters in Columbus, Ohio Selection Process ODOT will evaluate the LOI and may directly select a facilitator or they may “short list” a number of respondents and request additional information. Interviews of the “short listed” individuals are optional. The selection criteria for the LOI are shown below:

Appendix F

F-2

Selection factors are as follows:

• Overall experience in facilitating meetings between groups with divergent points of

view. • Experience facilitating meetings between government agencies and stakeholder

groups. • Training, education, and certifications related to providing facilitation services • Lack of detailed experience in the specific area of pavement engineering, design or

construction.

Appendix G Evaluation of the Future Maintenance Schedule

Appendix G

G-1

Evaluation of the Future Maintenance Schedule

At their November 18th meeting, the Pavement Selection Advisory Committee requested that the neutral third party (NTP) suggest an interim future maintenance schedule for ODOT. It was envisioned that this schedule would be used until ODOT could develop a new schedule based on survival curves. The NTP felt it was important that, where possible, the recommended schedule should reflect pavement performance and practices in Ohio. Because of time restraints, the NTP elected to focus on Interstate pavements; however, we believe the analysis approach used for interstate pavements can be duplicated for non-interstate routes with traffic less than 35 million rigid ESAL’s. To accomplish this task, the NTP requested the following information from ODOT:

1. During the past 5 years the percentage of mill and fill HMA overlays of Interstate asphalt pavements where full width milling, including the shoulder, was used. This should be broken down by functional overlays to correct surface distress and structural overlays.

2. For all functional HMA overlays constructed on Interstate asphalt pavements during the past 5 years, the time since the original construction of the pavement and (when applicable) the time since the most recently constructed prior overlay of the pavement. Also please provide the thickness of the overlay.

3. For all structural HMA overlays constructed on Interstate asphalt pavements during the past 5 years, the time since the original construction of the pavement and (when applicable) the time since the most recently constructed prior overlay of the pavement. Also please provide the thickness of the overlay.

4. For all structural HMA overlays constructed directly on PCC pavements during the past 5 years, time since the original construction of the pavement and the thickness of the overlay.

The information provided by ODOT in response to this request is included at the end of this appendix. Maintenance Schedule for HMA Pavements The data supplied by ODOT indicated that 12 HMA overlays were constructed on asphalt pavements during the last 5 years. This information was used to investigate three issues: 1) milling width, 2) overlay thickness, and 3) rehabilitation schedule. Milling Width The amount of milling required is an engineering decision based on the condition of the shoulder pavement. Table G-1 reflects the milling width used by ODOT during the past 5 years.

Appendix G

G-2

Table G-1. Interstate overlays.

District County Route Proj. # Structural Functional

ML or Full

Width Thickness2 LUC 475 358 X Full Width 3.25 5 FAI 70 440 X ML 1.5

5 LIC 70 316 X

ML (driving

lane only) 1.5 5 LIC 70 401 X ML +3’ 1.5 5 LIC 70 493 X ML 1.5 5 LIC 70 440 X ML 1.5 6 DEL 71 722 X Full Width 5.75

6 FRA 270 8000 X

ML + inside

shoulder 1.5 6 FRA 71 722 X Full Width 5.75 8 CLE 275 3012 X Full Width 3.25 8 CLE 275 2 X Full Width 3.25 8 CLE 275 172 X Full Width 3.25

The data indicate that, typically, milling only the mainline is required for functional overlays and full-width milling is required at the time structural overlays are constructed. The average milled with for all of the functional overlays was 25 feet. Based on a review of the data, the NTP recommends that milling of the mainline only be used for functional overlays and full-width milling be used for structural overlays. Overlay Thickness Observation of the data indicates that typically a 1.5-inch overlay is constructed when a functional pavement rehabilitation is required. During the last 5 years there were five projects calling for structural overlays. Two projects totaling 15.72 miles required a 5.75-inch overlay, and 3 projects totaling 11.01 miles required a 3.25-inch overlay. The weighted average of the overlay thickness was 4.72 inches. Based on a review of the data, an overlay thickness of 1.5 inches is used for functional overlays and an average of 4.75 inches is used for structural overlays. Rehabilitation Schedule Using the information supplied by ODOT relative to the pavement age at the time overlays were constructed during the last 5 years and the length of time since the previous overlay, a limited pavement history was developed for each of the sections. This history, shown in figure G-1, was used to develop a recommended rehabilitation schedule.

Appendix G

G-3

Figure G-1. Pavement history for HMA overlays constructed during the past 5 years.

District County Route Proj. # LengthTime to 1st Overlay

Time from Functional to Next overlay

Time from Structural to Next Overlay

2 LUC 475 358 3.72 12

5 FAI 70 440 2.38 10

5 LIC 70 316 3.58 6

5 LIC 70 401 5.09 7

5 LIC 70 493 6.41 2

5 LIC 70 440 9.55 10

6 DEL 71 722 11.5 8

6 FRA 270 8000 3.14 8

6 FRA 71 722 4.22 21

8 CLE 275 3012 5.35 17 14

8 CLE 275 2 4.44 16 16

8 CLE 275 172 1.22 s f 16 161 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48

Structural Overlay AVE 14 10 12Median 16 11 8

Functional Overlay Weighted Ave 13.1 9 12

Pavement Age (Years)

Appendix G

G-4

Analysis of the data contained in figure G-1 indicates that the weighted average time to the first overlay (functional) is 13.1 years. The weighed average life of a functional overlay is 9 years. The weighted average life of a structural overlay is 12 years. Based on this analysis, the indicated maintenance schedule would be to place the initial overlay (functional) at year 13, 2nd overlay (structural) at year 22, and third overlay (functional) at year 24. Comparison of the NTP’s analysis to ODOT’s current schedule is provided in table G-2.

Table G-2. Comparison of HMA rehabilitation schedules.

NTP’s Analysis ODOT’s Current Schedule 1. Year 13, 1.5” overlay with planing (mainline only)

1. Year 12, 1.5” overlay with planing (mainline and shoulder)



3. Year 34, 1.5” overlay with planing (mainline only)


While the NTP’s analysis used only a minimum amount of data, it tends to generally support the maintenance schedule currently used by ODOT. Maintenance Schedule for Rigid Pavements The data on overlaid rigid pavements were very limited; therefore, it was not possible for the NTP to draw any specific conclusions. The data tend to support the overly thickness being used according to ODOT’s schedule. The timing of ODOT’s maintenance strategies was higher than the median for the States reviewed. It is difficult to draw conclusions from the median values of the other States reviewed because of differences in climate, designs, and materials. The NTP felt that Pennsylvania was the State most similar to Ohio in the review sample. Pennsylvania’s schedule is shown on the next page. Since joint sealing is not normally performed on warranty pavement, the 10-year rehabilitation would not apply in Ohio. Based on a review of practices of other States, particularly Pennsylvania, the NTP arrived at the rehabilitation schedule for rigid Interstate pavements shown in table G-3. ODOT’s current schedule is shown for comparison. As in the case of HMA pavements, the NTP considers these to be minor modifications.

Appendix G

G-5

Table G-3. Comparison of PCC rehabilitation schedules.

NTP’s Analysis ODOT’s Current Schedule

1. Year 20 - Concrete patch 2% of pavement area diamond grind

1. Year 22: Diamond grinding (mainline plus one foot of shoulder), full depth repair 4% of mainline surface area;

2. Year 30 - Concrete patch 5% of pavement area, 3.25” asphalt overlay.

Year 32: 3.25" asphalt overlay, full depth repair 2% of mainline surface area.

Pennsylvania’s Rehabilitation Schedule for PCC Pavements 10 years - Clean and seal 25% of longitudinal joints Clean and seal 5% of transverse joints, 0% if neoprene seals are used Seal coat shoulders, if Type 1 paved shoulders 20 years - Concrete patch 2% of pavement area Diamond grind 50% of pavement area Clean and seal all longitudinal joints, including shoulders Clean and seal all transverse joints, 7% if neoprene seals are used Maintenance and protection of traffic User delay 30 years - Concrete patch 5% of pavement area Clean and seal all joints 600-psy leveling course 3.5-in. or 4-in. bituminous overlay Saw and seal joints in overlay Type 7 paved shoulders Adjust all guide rail and drainage structures Maintenance and protection of traffic User delay 35 years - Seal coat shoulders

Appendix G

G-6

Questions 1, 2, & 3 regarding asphalt interstates are answered belowNTP requested pavement information 11/20/03

District County Route Begin log End log Length Proj. # Year Activity Thickness Structural Functional ML or Full Width Years Since Original Const. Years Since Prior Overlay Prior Overlay Thickness2 LUC 475 5.25 8.97 3.72 358 2002 50 3.25 X Full Width 36 12 3.255 FAI 70 0 2.38 2.38 440 1998 50 1.5 X ML 105 LIC 70 20.26 23.84 3.58 316 2000 50 1.5 X ML (driving lane only) 46 6 1.5 ***5 LIC 70 23.84 28.93 5.09 401 1999 50 1.5 X ML 46 7 5.755 LIC 70 9.55 15.96 6.41 493 1999 50 1.5 X ML 47 2 1.55 LIC 70 0 9.55 9.55 440 1998 50 1.5 X ML 106 DEL 71 0 11.5 11.5 722 1999 50 5.75 X Full Width 41 0 1.256 FRA 270 33.86 37 3.14 8000 2000 50 1.5 X ML + inside shoulder 37 8 6.256 FRA 71 25.68 29.9 4.22 722 1999 50 5.75 X Full Width 42 1 3.758 CLE 275 0 5.35 5.35 3012 2000 50 3.25 X Full Width 31 14 2.58 CLE 275 5.35 9.79 4.44 2 2002 50 3.25 X Full Width 32 16 2.58 CLE 275 9.79 11.01 1.22 172 2002 50 3.25 X Full Width 32 16 2.5

Question 4 regarding the 1st overlay of concrete interstates is answered below

District County Route Blog Elog Length Proj. # Year Activity Thickness Structural Functional Years Since Original Const. Years Since Prior Overlay Prior Overlay Thickness12 CUY 90 9.7 13.41 3.71 180 1999 60 3.25 X 2510 NOB 77 11.22 18.92 7.7 94 1998 60 3.75 X 32

Dave Miller:Mainline plus 3 feet of inside shoulders.

Dave Miller:1.25" mill and fill placed in early 1999 to maintain traffic during multi-year construction. Prior overlay to that was 7 years earlier.

Dave Miller:1.5" mill and fill placed in 1998 to maintain traffic during multi-year construction. Prior overlay was 20 years earlier.

neutral third party - ohio department of transportation · december 31, 2003. upon issuing its...

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