MEPDG Overview & MEPDG Overview & National PerspectiveNational Perspective

CRSI Expert Task Group MeetingCRSI Expert Task Group MeetingJuly 29, 2008July 29, 2008

Gary CrawfordFederal Highway AdministrationOffice of Pavement Technology

OutlineOutline

1. The Beginning

2. Local Implementation Efforts

3. Integration of MEPDG into Practice

4. Enhancements

5. Summary

It’s Done; In Reality, It’s Done; In Reality, It’s the Beginning!!It’s the Beginning!!

April 2007 Irvine WorkshopApril 2007 Irvine Workshop

Should we wait until its Should we wait until its PERFECTPERFECT??

1958; Road Test initiated

1962; AASHO Road Test complete

1972; Interim Design Guide

1986; Update 1993; Update 2007; still not

perfect.

1989; LTPP initiated

1998; MEPDG initiated

2007; MEPDG delivered

Time, yrs.

4

10

24

31

45

AASHTO Guide MEPDG

Should we wait until its Should we wait until its PERFECTPERFECT?? If we wait until there are no more

changes, we will never use it. If we wait for perfection, it will be

impractical and cost will restrict its use.

There is NONO perfect procedure & it will never

be perfect!

OutlineOutline

1. The Beginning

2. Local Implementation Efforts3. Integration of MEPDG into Practice

4. Enhancements

5. Summary

Hawaii

Alaska

Timeframe for ImplementationTimeframe for Implementation

Using 2

Hawaii

Alaska

Timeframe for ImplementationTimeframe for Implementation

Using 2

1 – 3 yrs 17

Hawaii

Alaska

Timeframe for ImplementationTimeframe for Implementation

Using 2

1 – 3 yrs 17

4 – 7 yrs 9

Hawaii

Alaska

Timeframe for ImplementationTimeframe for Implementation

Using 2

1 – 3 yrs 17

4 – 7 yrs 9

> 7 yrs 1

Hawaii

Alaska

Timeframe for ImplementationTimeframe for Implementation

Using 2

1 – 3 yrs 17

4 – 7 yrs 9

> 7 yrs 1

No/Skipped 23

Does SHA Use or Plan to Use MEPDG?Does SHA Use or Plan to Use MEPDG?

Hawaii

Alaska

N0 -12

YES - 40

What factors are largest hindrance to What factors are largest hindrance to implementation?implementation?

States with no plans to implement Traffic data collection (6) Trained Staff (6) Material Characterization (5) Limited Staff (2) Lack of test sections (2) Climate data (1) Value added designs (1) Ability to replace models (1)

N0

YES

What factors are largest hindrance to What factors are largest hindrance to implementation?implementation?

States that plan to implement Material Characterization (20) Trained Staff (19) Traffic data collection (14) Lack of test section monitoring (14) Calibrating models (11) Limited Staff (5) Climate data (4) PMS data (1) Need to revise spec’s (1)

N0

YES

What efforts should be done at national What efforts should be done at national level?level?

States with no plans to implement Training (2) Calibration (2) Climate data (1) Traffic data inputs (1) Value added designs (1) Material characterization (1) Implementation guidance (1)

N0

YES

FHWA FHWA Summary Summary of Agency of Agency

PlansPlans

Efforts to Efforts to ImplementImplement

MEPDG MEPDG 20072007

0

20

40

60

80

100

Yes < 0.5 0.5 to 1.0 1.0 to 5.0 > 5.0

Range of Cost for Implementation Plan, $M

Pe

rce

nt

of

To

tal

Re

sp

on

din

g (

52

)

Does Agency Have Implementation Plan?

0

10

20

30

40

50

60

70

Yes < Design Life Equals DesignLife

> Design Life

Pe

rce

nt

of

To

tal R

es

po

nd

ing

(5

2) Does Agency Track Perfomance for Use in Calibration?

Implementation Areas & Implementation Areas & Technology TransferTechnology Transfer

Training & communications within & between departments

Traffic Materials Construction Calibration

Technology Transfer & Technology Transfer & Implementation ProductsImplementation Products

Remember Products: Management video Interactive CD for software Implementation notes Training course Guide text & appendices. User’s Manual in support of software.

Important Activities Important Activities for Implementationfor Implementation

Training Courses: Determining inputs & using software

Communication: Departments need to know what information is

needed & how it is used.

Establish sensitivity of inputs to distress Identify problem areas to reduce

frustration with software use

MEPDG – Local MEPDG – Local Validation/Calibration ToolsValidation/Calibration ToolsManual of Recommended Practice for Manual of Recommended Practice for

Calibration of M-E Based ModelsCalibration of M-E Based Models1. Confirming or adjusting the global calibration

factors.

2. Detailed and practical guide to complete local calibration.

MEPDG Software ItselfMEPDG Software Itself

NCHRP Project 1-40BNCHRP Project 1-40B

Previous & On-Going StudiesPrevious & On-Going Studies1. NCHRP 9-30 – Experimental Plan for Calibration &

Validation of HMA Performance Models for Mix & Structural Design.

2. NCHRP 9-30(001) – Conduct Pre-Implementation Studies & Database Enhancement.

3. NCHRP 1-40D – A review of the M-E PDG software & prediction methodology; & Correcting errors/blunders in the software.

4. NCHRP 1-40B – Local Calibration for the Recommended Guide for M-E Design of New and Rehabilitated Pavement Structures.

Previous & On-Going StudiesPrevious & On-Going Studies

Calibration Documents: NCHRP Digest 284, December 2003; Refining the

Calibration & Validation of HMA Performance Models: An Experimental Plan and Database.

NCHRP Digest 283, December 2003; Jackknife Testing – An Experimental Approach to Refine Model Calibration and Validation.

FHWA: Use of PMS data for local calibration. FHWA: Use of deflection basin data in the

MEPDG.

OutlineOutline

1. The Beginning

2. Local Implementation Efforts

3. Integration of MEPDG into Practice

4. Enhancements

5. Summary

Integration into PracticeIntegration into PracticeHow do I get How do I get

this input this input level 1 or 2 level 1 or 2 for design?for design?

A Major Issue – The A Major Issue – The Unknowns!!Unknowns!!

Determination of Determination of properties & other properties & other inputs.inputs.

Factors affecting Factors affecting properties needed for properties needed for design!!!!design!!!!• Source of MaterialsSource of Materials• ContractorContractor• Construction Construction

EquipmentEquipment

4-Day NHI Course for MEPDG

Software Training

OutlineOutline

1. The Beginning

2. Local Implementation Efforts

3. Integration of MEPDG into Practice

4. Enhancements5. Summary

DARWin-ME Project SolicitationDARWin-ME Project Solicitation

Project Solicitation Proposal Package Distributed July 1, 2008 Provides business case for supporting DARWin-ME

production software effort Funding commitments

18 agency participants required at $100,000/agency Total budget $1,800,000

15 – 18 month development cycle DARWin-ME will be based on:

Items identified by DARWin Task Force Independent source code review Joint Technical Committee on Pavements (JTCoP) input

AASHTO DARWin-ME AASHTO DARWin-ME Enhancements (ver 2.0)Enhancements (ver 2.0)Efficiency

Increased software speed Optimized for thickness

Functionality SI units Limit traffic growth to level of service

User Friendliness New GUI Input library database Batch mode function Import FWD backcalculation results Creation of new weather files with EICM Import traffic data from outside software Input validation checks Output select structural responses

Stability Fix existing and new “bugs”

OutlineOutline

1. The Beginning

2. Local Implementation Efforts

3. Integration of MEPDG into Practice

4. Enhancements

5. Summary

SummarySummary

Implementation Considerations: Regional design features not included in

global calibration. Regional defaults that are different from

global defaults. Design criteria as compared to

measured values included in calibration.

SummarySummary

77% of states plan to use MEPDG 54% plan to use MEPDG for statewide design catalogs 56% have plans to implement within 7 years Largest hindrance to implementation is:

Material Characterization (50%) Trained Staff (48%) Traffic Data (35%) Monitored Test Sections (35%) Local Calibration (28%)

Thank you.Thank you.Any Questions?Any Questions?