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Inland Empire Asphalt Pavement Study By ASCE Inland Empire – Pavement Committee

July 17, 2013

1.0 Introduction The ASCE Inland Empire Section formed a pavement committee to review the practices and options relative to asphalt pavement roadways in the Inland Empire. The Pavement Committee was formed as a result of the ongoing deteriorating infrastructure and tightening of funds for pavements and the need to make the best use of available funds. The committee was formed Spring 2011 and consists of 17 volunteers, who are listed at the end of this report. Committee members included civil engineers and pavement practitioners from private practice, local agencies, and universities. The study primarily focused on city and county roadways within the geographic area covered by the Inland Empire Section. This area generally includes most of northeastern Washington and northern Idaho. Our nation’s infrastructure has deteriorated, and there is a strong need to focus our efforts to repair it. The American Society of Engineers (ASCE) ranks the country’s infrastructure with a letter grade on a scale of A through F. The 2013 ranking for roads is a D. ASCE estimates that 32% of America’s roads are in poor condition costing $67 billion in vehicle repairs and operating costs, which is equivalent to about $324 per motorist. The current spending level for roadway projects is $91 billion per year. ASCE estimates that $170 billion per year is actually needed to substantially improve our roadways nationwide. The issue with the national roadways is similar to the roadways within the Inland Empire. The Committee conducted two surveys to find out what the primary issues and concerns were for pavement practitioners. Questionnaires were sent to local agencies within the Inland Empire. Questionnaires were also handed out at the Northwest Pavement Management Association (NWPMA) conference in 2011. Overwhelmingly the primary concern of pavement practitioners was the lack of funds for roadways. A summary of the Inland Empire questionnaire results are included in the appendices. While no in-depth study has been performed by the Committee, it is generally agreed that the condition of the nation’s roadways is indicative of those within the Inland Empire Section. Based on the survey results, it is estimated that the gap between what is currently spent and what is needed to bring local roadways up to acceptable standards at the national level can also be applied to the local area. For the agencies that responded to the surveys, the total budget for street and road work totals approximately $30 million. The budgets ranged from $60,000 to $15,000,000 with the average being approximately $3 million. If the national increase in budgeting recommended by ASCE were applied to the agencies within the Inland Empire Section, the total budgets for survey respondents would increase to over $79 million with the average increasing to over $7 million.

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This represents a 265 percent increase in budgets. While such an increase in budgets may be justified to improve local roadway condition, the political reality is that road and street work competes with other government managed activities. The current funding conditions indicate that budget increases will, at best, be only a small percent of the ASCE recommendations. This suggests that doing more with less will be required. Cost effective methods of pavement preservation; which extend the time before pavement reconstruction may help to not only maintain the current roadway conditions, but hopefully improve them were reviewed. Based on the current economic environment, it does not appear that funding to invest in roadways will increase anytime soon. For this reason, it is critical that our dollars be stretched by applying sound engineering principles and new technologies to develop and maintain the best paved roads possible. If road maintenance is not increased, and roads are allowed to fail, costs to reconstruct them in the future will escalate rapidly. The goal of this paper is to help advance the practice of pavement design, construction and preservation in the Inland Empire so that pavement funds are spent efficiently and effectively. This paper represents a beginning point to identify and disseminate information for alternative pavement management approaches. Pavement practitioners must thoroughly study each method and select the best one for the conditions before implementing the methods in design. The key elements the committee has identified for advancing pavement practice include:

Strive for continual improvement of best practices. Modify subgrade where needed. Implement long term pavement management strategies. Preserve existing pavements. Incorporate new and existing pavement technologies. Perform pilot projects to evaluate new methods and technologies.

1.1 Background The hard surface of a roadway is commonly referred to as the pavement, but there is more to it than the hard surface. Most native soils are not capable of supporting the heavy loads that are imposed through the tires of the vehicles that pass over them, especially busses and trucks. Over time, the need for better roads increased with traffic levels and the discipline of pavement design evolved. For many years, early American engineers had been characterized as not knowing how to design durable roads like the European engineers - especially the Germans, but nothing could be farther from the truth. The real difference is that in the United States. Funding was not available to build roads as durable and long lasting as the German roads. Even worse, once built, ongoing money to maintain them and protect our investment was not a priority. All roads, even German roads, begin to deteriorate as soon as they are built. Within 8 years after construction, preventive maintenance work should begin to get the full life out of them. This is especially true in the northern tier states where roads are subject to moisture penetration, and go through many freeze/ thaw cycles. When roads are not maintained, pavement design calculations are no longer valid because water can penetrate through the pavement, and weaken underlying layers and subgrade – shortening the pavement’s design life. When the

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preventive maintenance procedures are ignored and repairs are done after the damage is done, it becomes much more costly to provide an acceptable level of service. Roads begin with grading and compacting the native soils into a hard and dense mass, and then placing and compacting several more layers, or “lifts” of materials, each one stronger than the one beneath it. The intermediate layers are usually made up of various types of crushed stone, and they are sometimes treated with strengthening agents, such as Portland cement or liquid asphalt. The entire system, made up of compacted native soils, layers of crushed rock and hard surfacing is commonly referred to as the roadway “structure section”. Asphalt pavement is normally the top lift of the structure section; and it is made up of size graded stone and sand (aggregate) with liquid asphalt to bind the aggregate together, and special additives to enhance the workability and extend the life. Engineers take many factors into account when designing a pavement structure section. Vehicles add load to and stress the structure section. Since each vehicle uses some of the structure section’s life, the first task is to estimate the total amount of traffic the road will receive, and then estimate what percent of that traffic will be large trucks and busses. Cars and other light vehicles add slightly to the loads. For example, one passenger car has about 1/10,000 of traffic load as a heavy truck or bus. It is heavy trucks and busses that cause most of the loading. The Engineer must also estimate how much traffic will increase over its life for a given roadway. Additional factors that impact the design of a structure section include native soil conditions, weather conditions, availability of materials to utilize in the structure section, amount of money available for the project, users preferences, and political issues. The asphalt paving material used in heavy traffic areas is a product made up of 90-95% aggregate and sand and 5-10% liquid asphalt. The liquid asphalt is a semi-solid material at ambient temperatures, so the aggregate and liquid asphalt is heated to approximately 300°F and mixed in an asphalt plant. At that temperature, the asphalt is a liquid and it coats the aggregate. The asphalt/ aggregate mixture known as asphaltic concrete (AC) or hot mixed asphalt (HMA) is hauled to the roadway in dump trucks, spread on the road using a paver, and compacted with rollers of various types. The mixing, placing and compacting is a critical operation. All work must be completed before the temperature falls below 265°F, or the pavement life is shortened. If the mixture is heated to more than 350°F, the mixture is overly oxidized and the pavement life is shortened. When the hot asphalt mix arrives at the construction site from the plant, it is placed using an asphalt paver and compacted using asphalt rollers. Apart from laying the asphalt mix properly, the final quality of the asphalt pavement relies heavily on the quality of the asphalt mix delivered at the proper temperature, proper placement technique, and compaction with several heavy steel drum or rubber tire rollers to ensure suitable compaction. Finish rolling is implemented to provide a highly sealed surface and to improve ride. After the paving is complete, the road should have a minimum of 24 hours for the asphalt mix to completely solidify before it is used by heavy trucks, so that it can develop more strength. Shortening the time for solidification can adversely affect the quality and longevity of the pavement.

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The constant influences of traffic, rain, snow, heat, and cold weather causes the asphalt pavement and surface beneath it to begin slowly degrading. Asphalt preservation—including, but not limited to, crack sealing, pothole patching and chip sealing—can be used to protect and extend the life of asphalt pavement and the underlying layers of the structure section by limiting water penetration. The most costly and disruptive repairs on roadways are ones caused by base failures. Having a good base constructed under the pavement is crucial to the future pavement management plan. A good structure section will support the pavement so that the only types of treatments needed are the least expensive, and least disruptive, such as crack sealing and fog seals. 1.3 Pavement Life Cycle Pavement life cycle includes (1) pavement design, followed by (2) construction, which in turn is followed by (3) pavement management, the process of prioritizing necessary maintenance and repairs and then (4) pavement preservation, applying the right maintenance strategy at the right time. The following four sections describe options that can be used to improve each step of the process. 2. 0 Pavement Section Design Pavement designs in the Inland Empire often use the 1993 AASHTO Guide for Design of Pavement Structures, ITD Materials Manual, or prescriptive methods. Prescriptive methods are based on soil type and road class. Spokane County and the Kootenai County Associated Highway Districts both include prescriptive methods in their design standards. Soft soil, soils that retain water, perched/trapped groundwater, and freeze thaw conditions can tremendously impact pavement performance if they are not accounted for in design. These are the primary issues that must be accounted for in the design or premature deterioration of the pavement section could result. Additional factors include mix design and traffic loading, which are not discussed in detail in this report. If a pavement section is not adequately designed and constructed, preservation methods discussed in Section 4.0 might not extend the pavement life. In this situation, it is often necessary to reconstruct the pavement section to correct the design deficiencies. Some of the resources that are available for developing subgrade information to design the structure section include discussions with knowledgeable residents of the area, information such as soils reports, soil/geologic maps, and reports of soils exploration. Project-specific information is available from physical testing, such as subsurface exploration, laboratory testing and field load testing equipment such as the “falling weight deflectometer (FWD). The quality of data is generally proportional to the cost of the method used to obtain the data. Consequently, cost might out-weigh the benefit of improved data. However, the cost of correcting an inadequate structure section usually far out-weighs the testing, so the designer must apply careful judgment.

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A preliminary idea of the native soil types at subgrade can be estimated with the use of published information. We consider subgrade as the surface immediately below the structure section. Geological maps and soil data bases can be accessed via the internet, or in other published forms such as hard copy maps and reports. Sources of digital geological maps and soil databases include the following:

Agency Internet Address Idaho Geological Survey http://www.idahogeology.org/DrawOnePage.asp?P

ageID=51

USGS National Geologic Map Database

http://ngmdb.usgs.gov/ngmdb/ngmdb_home.html

Washington State Department of Natural Resources Geologic Information Portal

http://www.dnr.wa.gov/ResearchScience/Topics/GeosciencesData/Pages/geology_portal.aspx#interactive_maps

USDA, NRCS Web Soil Survey

http://websoilsurvey.nrcs.usda.gov/app/

2.1 Subgrade Improvement Methods The committee identified several commonly used subgrade improvement methods. Each method is briefly described below. Removal and Replacement of Unsuitable Soil with higher quality native Import Fill.

Use: Mitigate soft soil and freeze thaw conditions.

In most cases, this is the least costly strategy for repairing small pavement base failures. It is also cost effective work for well-trained in-house maintenance crews to perform as a part of the routine maintenance program, because it does not require specialized equipment or expertise. The unit cost for doing the work can vary widely, depending on the size of the excavation area and the depth. The bottom of the over-excavation will often need to be lined with a geosynthetic separation fabric and brought back to subgrade elevation by placing and compacting suitable fill in thin lifts. It is important to have technical expertise to determine the need for fabric, and to decide on the proper depth of excavation and dimensions of the replacement structure section. The location of borrow sources from the project site could dramatically impact the cost of this option. Thicker Base above Subgrade.

Use: Mitigate for soft soil and freeze thaw conditions.

Depending on subgrade strength and traffic loads; it might be possible to increase strength of the structure section by increasing the thickness of the pavement section. Frequently this is not an option. Most urban areas are curbed and the completed roadway section must match the curb. In rural areas, it is often not possible to increase the base thickness because the roads become narrower and conflict with ditches.

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Cement Treated Base (CTB). This method is similar to full-depth reclamation (FDR), which

is discussed in Section 6.0. Use: A methodology to construct a high strength structure section and mitigating freeze thaw effects.

This option involves mixing a small portion of cement into the existing roadway materials. It works best when the final gradation of material contains approximately 30% non-plastic fines. The process involves pulverizing the existing structure section and whatever depth of native soil is necessary to provide a structure section of the proper depth. The new structure section typically ends up being 8 to 12 inches deep, prior to surfacing. Next, 3% to 5% Portland cement by weight is mixed, processed, graded, compacted and allowed to cure for approximately 7 days. Immediately after mixing, CTB must remain moist or fog sealed during curing. Then a wearing surface of hot mix asphalt (HMA) or a bituminous surface treatment (BST) is applied. Additional information for cement treated base can be found at the Portland Cement Institute (http://www.cement.org). Lime treatment.

Use: soft soil with high percentage of clay. The process is nearly the same as CTB except that lime is substituted for cement.

Asphalt Treated Base (ATB).

Use: Soft or loose soil with a high percentage of sand and gravel with very few fines. ATB is about three times stronger than untreated granular base. Therefore, it is possible bridge softer subgrade with a thinner layer than would be required with a typical crushed aggregate base. Additional information for asphalt treated base can be found at the Washington Pavement Association (WAPA at http://www.asphaltwa.com).

Geogrids.

Use: Mitigate soft soil and other un-desirable characteristics of the native soils in the subgrade.

Geogrids can help improve construction on soft or problematic subgrades. Geogrids can also be used on competent subgrades to help extend pavement design life. Further information on the use, design, and installation of geogrids can be found at the Geosynthetic Institute (GSI at http://www.geosynthetic-institute.org).

Drainage Features.

It is important to control stormwater for traffic safety purposes, but it is also important to protect the road from stormwater. Water is very destructive to roads, and the efforts to maintain good drainage protects the structure section from premature damage. Every road that is not curbed must have ditches. Even when the terrain is so flat that water will not drain away from the road; ditches are still an important part of roadway design, because

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they allow the water to seep from beneath the structure section and evaporate. It is important that a part of routine maintenance includes restoring the drainage ditches to their original configuration.

3.0 Construction Best Practices The National Highway Institute has a series of video tapes that cover asphalt or pavement construction. These videos can be downloaded from their website at: http://www.nhi.fhwa.dot.gov/default.aspx This a good source for information about best practices for pavement construction. Asphalt construction best practices begin with proper planning and engineering, to ensure that an adequate pavement section is designed and specified to accommodate the projected traffic volumes and traffic loads on the local soil conditions. In best practices; this would involve performing a geotechnical investigation, to determine the soil conditions upon which the roadway is to be constructed, performing laboratory testing on those soils to determine their load bearing capacity, and then using an established pavement design methodology, which applies the projected traffic volumes and loadings to the soil properties to determine the appropriate thickness of asphalt and aggregate that should be placed on the soil once it has been compacted. Typical practice considers pavement design lives of twenty years. If soil conditions are fairly typical in a local region, engineers and local agencies often rely on experience and knowledge of the local soil conditions and properties, and apply that knowledge with previous testing and pavement design. Best practices require sound judgment, proper experience, and adequate verification that the soil conditions are as assumed during construction. Once a pavement structure section is designed to meet soil and traffic loading conditions, best practices requires that the roadway design condition be specified to the paving contractor. These specifications include the subgrade preparation and compaction; the type of crushed rock, its placement and compaction, and the asphalt type and its placement and compaction. Specifications not only dictate items such as allowable lift thickness, temperatures, and compaction; they also indicate frequency of field testing and observations during construction. Roadway construction can appear to be a very chaotic and hap-hazard business, but nothing could be farther from the truth. In fact, federal and state agencies have standards based on years of experience. Most local agencies also have special provisions, usually based on the state specifications, with some modifications to accommodate local conditions and preferences. Standard specifications are reviewed periodically, and changed to adjust to changing conditions. In most cases, the owner adds special provisions, the purpose of which is to adjust the standard specifications to fit the conditions of a specific project. One of the most critical best practices during construction is ensuring that a quality control program is in place, to verify that the roadway is being constructed to the design and specifications. This involves the contractor and typically an independent testing and inspection firm, and that representatives are onsite to verify the roadway products are being delivered and

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processed appropriately. Experience by all parties is important to insure the process is being properly followed. Experienced quality control personnel can ensure that the roadway construction will have minimal problems that occur such as pavement seam separation, subgrade failure, poor drainage, and/or shortened pavement life. Construction involves many uncontrollable variables. Hence, it is in the best interest of both the owners and contractors to collaboratively create an acceptable product, at a reasonable price. Road construction and maintenance in the northern tier states add complications that are seldom experienced in other parts of the country. One problem is that freezing and thawing of water in the structure section and the subgrade chisel the pavement apart, and slowly soften the gravel layers weakening the entire roadway. Another problem is that much of the construction and maintenance process requires good weather conditions, which means there is a short season when the work can be accomplished successfully. A third problem for those who are responsible for maintaining the road system involves available maintenance funds must be spent on activities, which do not enhance or protect our investment in infrastructure. Together, the best practices of ensuring a proper roadway design that provides drainage from the road surface, engineered asphalt design, properly written and conveyed specifications and quality control during the actual construction process, leads to a longer pavement life and overall reduction in maintenance costs. These best practices of building the roadway correctly are the first step in long-term pavement preservation. 4.0 PAVEMENT MANAGEMENT SYSTEMS Most money for construction and reconstruction of roadways comes from federal grants, with only a small portion provided by a local agency. The Federal Highway Administration (FHWA) was concerned that after an outlay of millions of dollars for reconstruction, the roads were not being properly maintained. Therefore, in 1993 there was a mandate that agencies implement a pavement management system, to ensure that pavement conditions would be monitored so proper pavement preservation strategies could be implemented to extend the road life. In the state of Washington; counties are required to develop and implement a computerized pavement management system, as a condition of their continued receipt of Motor Vehicle Fuel Tax revenue from the state. Over the last 40 years, WSDOT has done considerable work to develop a visual rating methodology with numerical scores rating the condition of pavements. Although it works well for WSDOT, not all of the processes worked well for local agencies. The agencies came together as a group, through the leadership of the Northwest Pavement Management Association (NWPMA) to standardize the changes. Most public agencies in Washington and Idaho are using some form of the WSDOT system to rate their roads, and it provides an excellent representation of the road condition. The system is based on starting new pavements with a score of 100 with points being deducted for the various types and amount of surface defects. Roads are typically rated in 0.10 mile segments. The following table was developed by the Committee based on the Committee’s experience and similar charts to provide general guidance. No single preservation strategy will work for everywhere because weather, traffic, subgrade, etcetera vary for each roadway. For this reason preservation condition strategy must take several variables into consideration.

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PAVEMENT CONDITION RATINGS AND STRATEGIES

PCI SURFACE CONDITION PRESERVATION STRATEGY 100 To 85 Excellent Crack Sealing, Fog Sealing 84 To 70 Good Minor Spot Repairs, Surface Seal 69 To 55 Fair Minor to Heavy Spot Repairs, Surface Seals, Thin

Overlays 54 To 40 Poor Heavy Spot Repairs, Thick Overlays 39 to 0 Failed (1) Reconstruct, Heavy Repairs, Thick Overlays Note (1): Not a preservation method, but it is included in the table to show consequence of not preserving.

The average PCI for an agency’s entire system is a realistic estimate of their over-all pavement condition, which can also be used to assist developing a budget for pavement preservation.

When the PCI drops low, into the 69 to 55 range, the cost per square yard for repair and preservation is substantially more than it is if it is done in the range of 70 and higher. With the advent of the visual rating and numerical scoring system, it has become easier to compare the relative cost of various pavement maintenance and repair strategies. Generally spending $1.00 for preventive maintenance when the PCIs are 70 and above will eliminate or postpone the need to spend $6.00 to $10.00 a short time later. This is illustrated by the chart below by the Federal Highway Administration (FHWA). By providing periodic low cost surface treatments, the pavements can be maintained in the good to excellent range well past the design life, and at a minimal cost.

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5.0 PRESERVATION METHODS Pavement preservation is a series of activities that are performed to preserve and extend the life of the pavement. It is similar to protecting the exterior of your house by frequently repainting - if paint is not kept up, further damage can occur resulting in costly repairs. Some of the maintenance activities include upkeep of drainage facilities and ditches, excavating and repairing small pavement failures, and various types of surface sealing. Ignoring the condition of pavements that appear to the motoring public to be in good condition, will lead to premature failure of our roadways resulting in costly rehabilitation or reconstruction. The most effective pavement preservation programs focus on pavements while they are still in good condition, before the onset of serious damage. By applying a cost-effective treatment at the right time, the pavement is restored almost to its original condition. Based on the surveys and experience of the committee, we identified preservation methods that are currently in use or could be used more often in our region. Many agencies have attempted to utilize new pavement preservation/ repair strategies that are described in trade publications and conferences, only to end up with a disappointing failure. It is important to recognize that not every application works in every situation, that the information obtained from trade publications and conferences and from this paper are merely an overview, and not all applications may fit every agency’s needs or goals. If a strategy appears to fit an agency, the first step is to ascertain the details such as the agency’s goal, expected life, engineering and construction details, total project cost and project unit cost. If time allows, it is best to monitor the project for several years, depending on how new and innovative the process is. Once that is done and it still looks like it is feasible, it is best to select the location carefully, keeping in mind that an agency’s successful project never makes the news, and failures often do. Pilot projects can be performed to help evaluate these methods. Several local agencies including the City of Spokane, Spokane County, and Wenatchee have had good success with pilot projects before fully implementing new methods. As mentioned previously, water is very destructive to our pavements. If it rained and snowed everywhere but on our roads, most highway and street work would be eliminated. Since that is not likely to happen, we need to prevent water intrusion into our pavements. The following preservation methods help seal pavements and reduce water penetration in the underlying layers and subgrade. When available we provide cost, contact, and frequency of use information. Much of the cost information below came from agencies located outside of the Inland Empire. This is because many of these methods are more frequently used by agencies outside of the Inland Empire. Fog Seals: Fog seals are a basic preservation treatment. The process involves spraying a coat of diluted asphalt emulsion on the surface of the pavement to waterproof it by filling the pours and micro-cracks, and to provide a protective coating to reduce the rate of oxidization. It leaves a very black surface, making it resemble a new pavement. The black surface coating is often worn off by the end of the first winter by studded tires, sand, and dirt. But the real benefit is the material that has soaked into the surface, and that is still in place. It is most effective on low

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traffic volume roads, such as residential streets and rural feeder roads. The typical life is 2 to 5 years.

Variations: Fog seals with Asphalt Rejuvenators: http://www.techtransfer.berkeley.edu/icpp/papers/47_2010.pdf

Asphalt rejuvenators are similar to fog seals, but incorporate a solvent based material, which softens the pavement surface. As pavements age, essential oils are lost as they volatilize from the pavement leading to cracking and pavement failure. Rejuvenators penetrate the asphalt, restore essential oils, rejuvenate the asphaltic binder and repair damage within the asphalt matrix. Under heavy traffic, smaller cracks may see some degree of closure. It is frequently used to reverse the effects of premature pavement aging in hot, dry climates, such as the Columbia Basin. Basic cost generally ranges from about $0.1 to $0.15 gallon per square yard, plus about 35% for equipment and labor. These costs are variable and can change dramatically over short periods of time.

Crack Sealing: Filling or sealing pavement cracks to prevent water from entering the base and sub base will help extend the pavement life. Filling cracks and joints with asphalt materials is not new. These pavement repair techniques have been commonplace practices for decades. The asphalt materials are intended to fill the crack and keep most of the water out of the pavement. It should always be done prior to asphalt overlays, because it helps to retard reflective cracking through the new overlay. It should also be done prior to surface sealing because only the smallest cracks are filled with the surface sealant. It is also cost effective to fill cracks whether or not other work is scheduled. Crack filling products are formulated for this purpose with additives, to enhance the flexibility and ability to bond to the edges of the crack. The two main types are cold poured emulsified asphalt, and hot poured rubberized asphalt. Both have their own advantages and disadvantages. http://www.usroads.com/journals/rmej/9908/rm990801.htm Chip Seals: http://nwpma-online.org/resources/2010.17_Wood_ChipSeal-BestPractices.pdf Chip sealing is a cost effective surface treatment that helps seal the road surface and increase skid friction. Chip sealing is being used more frequently by cities and counties throughout the country. Chip sealing has several disadvantages, which include dusty chips, the loose chips should be left on the road for 12 to 24 hours before they can be broomed off, which could result in windshield rock chips. Depending on weather conditions, brooming could be acceptable after 12 hours. Chip seals are also noisier and have a rougher surface than HMA. The success of a chip seal project is highly dependent on the contractor’s and local agency methods, both of which can have considerable experience with this practice. The application of Chip Seal for pavement preservation has received mixed reviews when used in an urban environment. While the treatment can be a cost effective method to prolong

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pavement life; the appearance, roughness, and common construction practices during the application can create a negative impression from the general public. Efforts within the construction industry to increase the popularity of using chip seal in an urban setting, have led to various mix designs. One of those mix designs consists of ¼-inch rock chip, as opposed to the traditional 3/8-inch rock chip. This smaller sized rock gradation provides a smoother surface. If the chip seal receives a final fog seal after application, the appearance improves from a dusty looking surface to a black asphalt appearance creating a more favorable impression from the general public. The fog seal not only helps with the rideabliltiy and appearance, its application helps to hold the chips in place and fill some of the surface voids within the chip seal. This combined product, ¼-inch chip seal with a fog seal, has a tendency to knead over time from traffic, creating a smoother road surface similar to an asphalt overlay. To address the concerns from chip seal construction, local agencies have been working with contractors to help refine the specifications regarding the methods of application practices. In doing so, they dramatically reduced the amount of chip rock and oil carry off that occurs during the chip sealing operations. A team effort by the local contractors and agencies to contain the chip product to the work area is one of the most effective methods of gaining public favor. As local agencies strive to stretch their available maintenance dollars for road preservation, the ¼-inch chip seal shows great promise in helping to meet that goal, and receive a more favorable impression in the urban setting. It is anticipated that the local agencies, contractors, and engineers will continue to refine the specifications of this product to meet these goals.

Costs, Contacts, and Frequency of Use Approximate Cost: $3.70 per square yard (Clark County subcontractor for chip seal,

City of Vancouver – prep, striping) $1.50 per square yard (City of Post Falls and Stevens County) Local Contacts: Thurston County – Diane Sheesley (sheesid@co.thurston.wa.us) City of Hillsboro, Oregon – josephh@ci.hillsboro.or.us Clark County – Linda Small (linda.small@clark.wa.gov) Snohomish County – Joyce Barnes (425.388.3488, ext. 4530) City of Kirkland – Andrea Dasovich (adasovich@ci.kirkland.wa.us) City of Vancouver, Washington – Ryan Miles (360.487.7708) City of Spokane – Mark Serbousek (509.232.8810) Spokane County – Howard Hamby (509.477.7458) City of Post Falls – Jim Porter (jporter@postfallsidaho.org) Frequency of Use: City of Vancouver – 8 to 11 years, working towards 7 to 9 year

range City of Hillsboro – 7 to 10 years Clark County – 7 years

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Snohomish County – 7 to 10 years City of Kirkland – approximately every 7 years Thurston County – no set schedule, work by quadrant

Slurry Seals: http://www.nwpma-online.org/FTP/09Fall_02_Seal-Innovs_CWorden.pdf Slurry Seal is a mixture of fine aggregate, asphalt emulsion, water, and sand that is squeegeed onto the pavement in a thin layer. The components are mixed and placed on the road using a single machine. Slurry sealing is a surface treatment that seals and waterproofs the surface while correcting minor defects and improving skid resistance and appearance. It usually takes 4 to 6 hours for the material to harden enough to allow traffic, and it remains tender for several days. The thin surface is a suitable choice for city streets. However the material is brittle and pavement cracks soon reflect through it. It is very susceptible to excessive studded tire wear. Variation in the binder Micro-surfacing is a high-performance slurry seal, formulated with polymers for a very quick cure and traffic return, as well as durability on high traffic pavements. Since micro-surfacing cures quickly, it can be placed thicker than slurry seals and used to fill ruts and for minor re-profiling. These seals can be placed on both asphalt and concrete pavements. Cape Seals: Occasionally the most economical strategy is to use a chip seal on a residential street or group of streets; but aesthetically, the chip seal is not acceptable because of the rough noisy ride of a chip seal road. One option to improve the ride of a chip seal road is to use the cape seal. A Cape seal is a chip seal that is followed with a slurry seal on top of the chip seal to provide a smooth road surface. The disadvantage of this treatment is that it is approximately twice the cost as either the chip seal or the slurry seal. Costs, Contacts, and Frequency of Use Approximate cost: Slurry seal + chip seal – $6.50 per square yard (City of Medford)

Slurry seal + chip seal – $11.50 per square yard (Medford area private contractor)

Slurry seal + chip seal – $5.50 per square yard Slurry seal alone – $2.00 per square yard (City of Vancouver)

Type 2 Micro seal alone – $3.00 per square yard (City of Vancouver) Type 3 Micro seal alone – $5.00 per square yard (City of Vancouver)

Local Contact: Medford, Oregon – Tad Blanton (541.774.2600)

Hillsboro, Oregon – josephh@ci.hillsboro.or.us Clark County – Linda Small (linda.small@clark.wa.gov) City of Vancouver, Washington – Ryan Miles (360.487.7708) Frequency of Use: City of Medford – 7 to 9 years for slurry seal City of Vancouver – 8 to 11 years, working towards 7 to 9 year range

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Asphaltic Concrete Overlays: An asphaltic concrete overlay is a layer of asphaltic concrete applied on top of an existing hard surfaced road to increase the strength and improve the profile and cross section shape. The existing pavement structure section is repaired, as needed to restore as much of its previous structural capability and resistance to moisture penetration. Then a thin film of asphalt emulsion is applied to help bond to the new lift to the old, and one or more layers of new asphaltic concrete is applied typically from 1 to 6 inches thick. 6.0 ALTERNATIVE METHODS The alternative pavement methods discussed in this report include new technologies and some existing technologies. As with the above preservation methods, pilot projects would help introduce these methods to the region. We discuss several of these methods below. When available we provide cost, contact, and frequency of use information. Crack Retardant Fabrics and interlayer systems: http://www.webs1.uidaho.edu/bayomy/IAC/49th/Presentations_09/6.%20Reflective%20Crack%20Mitigation%20with%20Paving%20Fabrics_DAllhouse_IAC09.pdf As asphalt pavements age, they lose much of their flexibility and begin to develop cracks. Over time, these cracks reflect through the new overlays. There are many strategies to slow crack reflection. Placing a layer of geotextile fabric, geogrid, or geocomposite and bonding it to the old pavement prior to the overlay is one way to retard reflective cracking on overlays. Depending on project conditions, they have varying degrees of success. Similar to overlay projects, the first stage is to repair the various types of damage to the existing pavement. After performing repairs; the existing road is primed with liquid asphalt emulsion, and the fabric is placed on top and rolled to bond it to the pavement. When that has properly set, the overlay is applied. The value of using these products comes from extending the life of the overlay. Fabrics provide waterproofing while fiberglass geogrids provide pavement reinforcement. There are also high-performing composites that combine fabrics attached to fiberglass geogrid for a dual functioning product. This system can be used in conjunction with several of the systems described in this report. Costs, Contacts, and Frequency of Use Approximate cost: $1.00 to $1.50 per square yard (City of Medford) Local Contact: City of Medford –Tad Blanton (541.774.2600) City of Kirkland – Andrea Dasovich (adasovich@ci.kirkland.wa.us) City of Tigard – Mike McCarthy (503.718.2462) Fiber Additives for Asphalt: Another potential option to reduce cracking is using fiber additives mixed into the asphalt. These fiber additives have historically been stranded materials such as polyester, polypropylene, and even steel. A newer fiber asphalt additive that has shown significant results in cracking and rutting resistance is aramid (also known as Kevlar). The material is

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mixed in at the asphalt plant and gives asphalt more tensile strength and durability to resist cracking and deformation rutting. Whether an asphalt layer is under top-down or bottom-up stresses, cracking can develop because asphalt is not as strong in tension as it is in compression. This tensile failure, or crack, is when the bitumen binder can no longer hold the stress so it ruptures. Fibers like aramid are very strong in tension and provide the reinforcement to the bitumen to resistant these tensile forces that cause cracking. Fibers like aramid have also been found to resist rutting in asphalt because they do not deform under heat and stress. With the benefits that fiber additives provide to asphalt, users can realize better performing pavements that last longer, resulting in better life cycle costs. They can also reduce pavement layer thickness to save money without sacrificing performance of the pavement. More information about fiber additives can be found in a paper written by Dr. Kamil Kaloush with Arizona State University, “Evaluation of Fiber-Reinforced Asphalt Mixtures Using Advanced Material Characterization Tests”. Costs, Contacts, and Frequency of Use Approximate cost: $1.00 to $1.25 per square yard (City of Medford) Local Contact: City of Medford –Tad Blanton (541.774.2600) City of Beaverton – Debbie Martisak (503.350.4084) City of Tigard – Mike McCarthy (503.718.2462) Thin and Micro Thin Overlays: http://nwpma-online.org/resources/09Fall_12_Thin-UltraThinAcOLs_JimHuddleston.pdf Micro thin overlays are only ¾- to 1-inch thick. Their main purpose is to correct minor surface roughness and to act as a surface seal reducing water from penetration into the structure section. They are constructed with asphaltic concrete, using 3/8 in maximum size aggregate for ¾-inch overlays, and ½-inch maximum size aggregate for 1-inch overlays. Traditionally, it was believed to be unwise to apply overlays less than 2 inches thick because they frequently “delaminated”, a condition where the new overlay peels off the old pavement. To minimize this action, a thick coating of liquid asphalt is applied to improve the bond between old and new and by providing proper compaction and paying careful attention to temperature limitations for ambient roadway and mix, and by completing all compaction efforts before the HMA is out of the temperature range. This process is only a water proofing or sealing process, generally providing no additional strength to the roadway. Under certain conditions, alligator cracking can begin to reflect through the thin overlay. The life of the thin overlay can be prolonged by applying a fog seal over the alligator cracking. Costs, Contacts, and Frequency of Use Approximate cost: $1.00 to $1.50 per square yard (City of Medford) $4.00 per linear foot (Spokane County) Local Contact: City of Medford – Tad Blanton (541.774.2600)

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City of Kirkland – Andrea Dasovich (adasovich@ci.kirkland.wa.us) City of Tigard – Mike McCarthy (503.718.2462)

Spokane County – Howard Hamby (509.477.7458) Frequency of Use: Spokane County – 15,000 lineal feet in 10 years Ultra Thin White topping: http://www.nbmcw.com/articles/roads/21927-white-topping-an-excellent-solution-for-pavement-rehabilitation.html A Portland cement concrete (PCC) overlay on an existing bituminous pavement is commonly known as white topping. The principal purpose of an overlay is either to restore or to increase the load carrying capacity or both, of the existing pavement. In achieving this objective, overlays also restore the ride-ability of the existing pavements which have suffered rutting and deformations, in addition to rectifying other defects such as loss of texture. Costs, Contacts, and Frequency of Use

Approximate cost: $37.85 per square yard at 2-inch depth Local Contact: City of Portland – Eva B. Huntsinger, P.E., JD (503.823.7562) Frequency of Use: Not available

Reconstruction: At some point in time, it becomes more cost effective to reconstruct roads. Sometimes this happens because there is no cost effective method of maintaining the existing structure section. Also, traffic characteristics may have changed enough that the existing road cannot be modified to support the new loading. The most commonly used process is to remove the existing failed structure section and native material to the proper depth and replace it with a new section designed for the current and future conditions. Full-Depth Reclamation (FDR) Full Depth Reclamation: http://www.cement.org/pavements/pv_sc_fdr.asp Full-depth reclamation uses the materials from the deteriorated, structure section and sometimes the native soils. The existing roadway is pulverized and small amount of Portland cement is added and mixed with the pulverized material on the road and hydrated with water. The amount of cement is about 4 to 6 percent by weight of the mixture. This mix is then graded and compacted and allowed to cure (harden) for one or two weeks, before a surface course is applied. The surface is usually a double or triple chip seal or a HMA overlay. The recycled base is stronger, more uniform, and more moisture resistant than the original base, resulting in a long, low-preservation life. The costs are normally 25% to 50% less than the removal and replacement of the old pavement. This process has been used in the Spokane area for about 12 years and in Stevens County for over 15 years. It was first used to strengthen roads with heavy truck traffic, so that spring time load restrictions would no longer be required. It has proved to be a cost effective strategy for reconstructing roads with weak structure sections. Costs, Contacts, and Frequency of Use Approximate cost: $45 per square yard (City of Vancouver, WA – for CTB)

$500,000 per mile (Stevens County)

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$179,000 per mile (Spokane County – includes 3” Crushed Surfacing Top Course (CSTC) and 2 shot seal)

Local Contact: Stevens County – Jim Whitbread (509.684.4548) City of Vancouver, WA – Ryan Miles (360.487.7708) Spokane County – Howard Hamby (509.477.7458) Frequency of Use: Stevens County – all grant funded projects intended to improve the

primary road system Spokane County – on 10 roads in the past by County Also used by Developers in Spokane County

Hot in Place Recycle: http://www.smoothroads.com/tp/hot_in-place_recycling.htm Hot in-place recycling (HIPR) is a less common and more specialized form of asphalt recycling. There are three basic HIPR construction processes in use, all of which involve a specialized plant in a continuous train operation. This method uses a plant that heats the pavement surface (typically using propane radiant heaters), scarifies the pavement surface using a bank of non-rotating teeth, adds a rejuvenating agent to improve the recycled asphalt binder viscosity, then mixes and levels the recycled mix using a standard auger system. The recycled asphalt pavement is then compacted using conventional compaction equipment. Cold in Place Recycle: http://www.fhwa.dot.gov/pavement/recycling/98042/13.cfm In the cold mix in-place recycling process, existing in-place materials are mixed with recycling agents and/or new or reclaimed materials without the application of heat. The method can be used to eliminate a variety of distresses such as rutting, cracks, and irregularities while maintaining the original profile and with a minimum traffic disruption. Costs, Contacts, and Frequency of Use Approximate cost: $3.50 per square yard (pulverize, grade, shape) + $70.00/ton HMA Local Contact: City of Vancouver – Ryan Miles (360.487.7708) Polymer modified HMA

In this process, a polymer rubber, typically latex, is blended into the liquid asphalt that is used to produce the asphaltic concrete. It improves the flexibility of the asphaltic concrete at lower temperatures, which is a desirable quality in the Inland Northwest where there are large temperature variations, and it is quickly becoming the standard of the industry.

Rubberized HMA http://www.ecst.csuchico.edu/~dxcheng/RAC_Resources/Asphalt-Rubber%20Information%20Index%20Page.mht This method uses rubber melted pellets from tire recycling, and is added to the hot mix to be used. The Rubberized Hot mix improves the ability to retard surface cracking and has been shown to increase the life of pavements. This method has been used successfully in environments like the Inland Northwest.

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Warm Mix Asphalt: http://www.californiapavements.org/corrigan.pdf This process uses a chemical or foaming agent that is injected into the HMA mixing drum that typically allows proper coating and mixing at temperatures 30°F to 50°F lower than conventional HMA mixing and remains workable, such drastic reductions have the obvious benefits of cutting fuel consumption and decreasing the production of greenhouse gases. In addition, engineering benefits include better compaction and performance on the road, the ability to haul paving mix for longer distances, and extending the paving season by being able to pave at lower temperatures. This is the newest innovation in the industry and is being widely accepted. Currently most paving companies in the Spokane are expecting to convert to WMA operations soon. Costs, Contacts, and Frequency of Use Approximate cost: $53.00 per ton (City of Medford) Local Contact: City of Medford – Tad Blanton (541.774.2600) City of Hillsboro – josephh@ci.hillsboro.or.us Frequency of Use: City of Medford – overlay at 15 years Reclaimed Asphalt Product (RAP): Reclaimed Asphalt Product (RAP) is created when roads are milled. FHA estimates that 100 million tons of HMA is milled, annually. WSDOT and the City of Spokane currently allow 20% of RAP to be recycled into new HMA. More RAP is being used in alternative ways to keep old asphalt out of landfills. WSDOT and the City of Spokane currently allows 50% of RAP to be used in base aggregate. RAP has extreme variability and many unknowns due to milling processes, location, mix designs, aggregate type, etc. Because of the variability and unknowns, it is unlikely that the allowable percentages of RAP will increase until more testing of RAP mix designs are performed. Perpetual Pavements: Pavement designs are typically designed for a 20-year life. Perpetual pavements are designed for a perpetual life, which increases the pavement thickness, but won’t require reconstruction if they are properly maintained and preserved. The minimum asphalt thickness for perpetual pavements is about 5 to 6 inches. Since the asphalt layer is relatively thick, the mode for cracking becomes predominately top-down instead of bottom-up. Top-down cracks can be managed from the surface with methods such as grind-and-overlay without having to reconstruct the entire pavement section. Perpetual pavements generally have a higher initial cost than standard pavements, but the higher cost is made up by not having to reconstruct the pavement in the future. Engineering Traffic Solutions: Engineering traffic solutions to pavement management involves shifting lane alignments to move the wheel tracks and narrowing lanes to reduce the area of pavement impacted by traffic. Roundabouts could be used as an engineered traffic solution. Traffic calming also reduces speeds, which reduces the stopping impacts to pavements at intersections.

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7.0 CONCLUSION Roadways in the Inland Empire are a valuable asset to our communities and region. We need to protect this asset otherwise costs to repair or reconstruct roadways will increase exponentially in the future. We have identified several methods that are being used and/or could be used to improve pavements in the Inland Empire. Future committee work could identify additional methods. We have also provided contact and technical sources to find additional information about specific methods. Future work of the Pavement Committee will likely include further study of pavement design methods, construction best practices, pavement management systems, alternative preservation and pavement methods, and a discussion of how pavement and pilot projects performed. The Committee would also like to engage more construction contractors, local agencies, and consultants throughout the Inland Empire for input. Committee Members: Chris Sneider, PE, M. ASCE (Chairperson-Sneider Engineering), Phil Barto, PE, M. ASCE (Fleet Services), Dr. Fouad Bayomy, PE, M. ASCE (University of Idaho), Chad Coles, PE (Spokane County), Kelvin Daratha, EIT, Student Member ASCE (Washington State University), Rebecca Derby, (BWA), John Finnegan, PE, M. ASCE (Budinger and Associates), Howard Hamby, Pavement Manager (Spokane County), Steve King, PE, M. ASCE (Wenatchee), Paul Lennemann, PE, M. ASCE (Spokane County), Bill Melvin, PE, M. ASCE (Post Falls), Gary Nelson, PE, M. ASCE (Spokane), Mark Serbousek, PE (Spokane), Laura Sliger, M. ASCE Dr. Shihui Shen, M. ASCE (Washington State University), Hank Swift, PE, GE, M. ASCE (HKS Engineers), Jim Whitbread, PE, M. ASCE (Stevens County) References: AASHTO Guide for Design of Pavement Structures. 1993. American Association of State Highway and Transportation Officials, Washington, D.C. American Society of Civil Engineers (ASCE), March 2013. 2013 Report Card for America’s Infrastructure. www.infrastructurereportcard.org Spokane County Road Standards. 2010. Spokane County Engineers, Spokane County Washington. January. Washington State Department of Transportation (WSDOT). 2010. Standard Specifications for Road, Bridge, and Municipal Construction, Olympia, Washington. Highway Standards for the Associated Highway Districts, Kootenai County Idaho, 2005

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Meeting with Inland Northwest Associated General Contractors (AGC) February 16, 2012. 4935 East Trent Avenue, Spokane, WA 99212 Appendices: Summary of Inland Empire Agency Questionnaire

ASCE Pavement Committee Questionnaire Summary October 2011

Page 1  

AGENCIES RESPONDING Cities Counties Federal

Coeur d’Alene, Idaho Spokane Fairchild Air Force Base Post Falls, Idaho Ferry

Colville, Washington Stevens Deer Park, Washington Pullman, Washington Spokane, Washington

Spokane Valley, Washington

QUESTIONS

1. How many lane miles of paved roadways are within your jurisdiction?

Miles Agencies

<50 2

50 – 100 1

100 – 150 1

150 – 200 1

500 – 550 2

900 – 950 1

950 – 1000 1

1,000 – 1,500 1

2,000 – 3,000 1

2. What is the agency’s total budget for maintenance of these roadways?

Amount Agencies

NR 1

$60,000 1

$100,000 1

$404,564 1

$790,000 1

$1,000,000 1

$2,323,400 1

$2,400,000 1

$2,900,000 1

$5,000,000 1

$15,000,000 1

ASCE Pavement Committee Questionnaire Summary October 2011

Page 2  

3. Is maintenance performed by the jurisdiction, by others, or a combination thereof?

Entity Agencies

Jurisdiction 5

Jurisdiction except for major resurfacing 1

Combination 4

Others 1

4. What is your rating for rural residential (FFC9) and urban residential (FFC10) pavements? If you are in Idaho, please use your local rating system.

Rating System Agencies

FFC10 57 1

FFC9 <60 1

FFC9 68 1

OCI 69 1

FFC9 73 1

OCI 74 1

PCI 80 1

PRC 80 (average) 1

NR 4

5. Do you have a typical pavement section for your various road classifications? If so, please indicate:

a. Residential Streets

Asphalt/Gravel Agencies Subgrade Compaction Agencies

2”/6” 4 95% 9

3”/6” 2 95% (Mod) Upper 6”

90% (Mod) below 1

2”/4” 2 95% upper 2’ 1

2”/8” 1

3”/4” 1

3”/12” 1

0”/3” 1

ASCE Pavement Committee Questionnaire Summary October 2011

Page 3  

b. Collector Streets

Asphalt/Gravel Agencies Subgrade Compaction Agencies

0”/12” 1 95% WSDOT standard 2

3’/4”-6” 1 95% 6

3”/6” 1 95% upper 2’ 1

4”/6” 1 95% (Mod) Upper 6”

90% (Mod) below 1

4”/6” (min Design Req) 1

Design Required 1

3”/8” 1

3.5”-4.5”/6”-7.5” 1

4”/8” 1

3”/12” 2

c. Arterial Streets

Asphalt/Gravel Agencies Subgrade Compaction Agencies

2”/12” 1 95% WSDOT standard 2

3”/6” 1 95% 6

4”/4”-6” 1 95% upper 2’ 1

4”/6” 1 95% (Mod) Upper 6”

90% (Mod) below 1

4”/6” (min Design Req) 1

Design Required 1

3”/8” 1

3”/12” 2

4.5”-5”/7.5”-8.5” 1

4”/8” 1

4”/10” 1

4”/12”-16” 1

ASCE Pavement Committee Questionnaire Summary October 2011

Page 4  

6. Does your agency have an adopted pavement design methodology? If so, please describe:

Method Agencies

Yes 9

R-Value 1

WSDOT Guidelines 1

Based on Provided Geotechnical Report 1

WSDOT Guidelines w/Alternate Methods 1

Rational Method Based on AASHTO Using ESALs and Subgrade Support Values

1

1993 AASHTO Guide for Design of Flexible Pavement Structures

3

PCASE (USACOE) 1

No 2

7. Please describe your routine maintenance program to preserve the life of your pavements. A description of the methods used (crack sealing, overlays, sealing, etc.) and the frequency, of those methods.

Maintenance Activity Agencies

NR 1

Crack Sealing every year 3

Crack Sealing every 2 years 1

Crack Sealing every 7 years 1

Crack Sealing @ 30,000 LF/yr 1

Crack Sealing (No interval) 4

Pulverize & Repave 1.5 – 2 miles/yr 1

Patching (Based on pavement rating) 1

Patching (No interval) 1

Patching (7-year Interval) 1

Thin Lift Overlay (Based on pavement rating) 2

Reconstruction (Based on pavement rating) 2

Reconstruction (Based on budget) 1

Reconstruction (@ Failure) 1

(continued on next page)   

ASCE Pavement Committee Questionnaire Summary October 2011

Page 5  

Maintenance Activity Agencies

Chip Seal (No interval) 1

Sealing (After one year) 1

Sealing (Seven-year frequency) 2

Sealing (Five-year frequency for collector and arterials 1

Grind/Overlay (Worst case first) 1

Grind/Inlays 1

Grind/Mix & Repave (Based on budget) 1

Pot Hole Repair every year 2

Sweep All Streets once per month 1

No Routine Maintenance 1

8. What other alternative maintenance methods are you interested in and would consider using, if you had more information on those methods and local contractors’ willingness to employ those methods?

Method Agencies

NR 2

None 3

Cement Treated Base 1

Pre-coated Chips 1

Warm mix Thin Asphalt Overlays 1

Fast Cure Seals 1

Slurry Seals 2

Chip Seal 2

¼” Chip Seal 1

Chip Seal Alternatives 1

Cape Seal 1

Micro Seal 2

Any Inexpensive Means 2

ASCE Pavement Committee Questionnaire Summary October 2011

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9. Do you use pavement management data to develop your maintenance and reconstruction program? If so, how do you use it?

Data Agencies

Yes 11

WSDOT Pavement Rating System 2

Pavement Management Software 3

O.C.I. 1

Consultant Developed System 1

No 0

10. What are the major types of pavement failures / issues affecting your agency?

Failure/Issue Agencies

Worn Out Pavement 1

Longitudinal Joints 1

Construction Joints 2

Rutting 2

Structural 1

Weather 4

Material 1

Subgrade 2

Funding 2

Old Asphalt 1

Raveling 2

Cracking 2

Asphalt Deterioration 1

11. What are the major issues that you see facing your agency in regards to pavement

preservation?

Issue Agencies

Funding 11

Manpower 1

Bid Prices 1

Preservation Alternatives, Approaches, & Timing 1

ASCE Pavement Committee Questionnaire Summary October 2011

Page 7  

12. Maintenance:

Issue Agencies

NR 9

Funding 2

Alternatives 1

Material Costs 1

13. Construction Practice:

Issue Agencies

NR 4

Contractor Understanding 3

Local Training Classes 1

Failure of Poor Joints (New Pavement versus Old) 1

Funding 2

Material Quality 1

Poor Soil Conditions 1

14. Are there specific issues that you would like the committee to address?

Issue Agencies

NR 6

Pavement Design Practices 1

Studded Tires 1

Pre-mature Asphalt Failure 1

Innovative, Cost Effective Repair Strategies 1

National Asphalt Oil Supply & Demand 1

Jurisdiction Maintenance Personnel Training 1

Funding 2

ASCE Pavement Committee Questionnaire Summary October 2011

Page 8  

15. General Comments

Comment Agencies

NR 9

I think that this committee is a great way to bring together all parties and to seek out better ways to improve our local roads through construction techniques, proper management and research.

1

Better planning prior to paving to minimize roadway utility cuts. 1

¼” chip seal with fog seal is receiving better acceptance from community. 1

¼” rock price has lowered in the last couple of years. 1

Seal must have a high flash time (20 minutes) to minimize traffic disruption. 1

Funding will always be an issue and maintenance must be approached in a logical and systematic manner to not waste those available funds.

1