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Publication Number: FHWA-HRT-13-089
Date: October 2013

 

Long-Term Pavement Performance Pavement Loading User Guide (LTPP PLUG)

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FOREWORD

This guide addresses the selection and use of axle loading defaults for Mechanistic-Empirical Pavement Design Guide (MEPDG) applications. The defaults were developed based on weigh-in-motion (WIM) data from the Long-Term Pavement Performance (LTPP) Special Pavement Study (SPS) Transportation Pooled Fund Study (TPF). The guide consists of two parts. The first part provides guidelines for selecting and using LTPP SPS TPF axle loading defaults with the MEPDG and DARWin-ME software. These defaults provide a source of axle loading information for pavement analysis for locations where site-specific axle load spectra are not available. The second part of the guide provides practical guidelines that States and LTPP can use to generate additional MEPDG traffic loading defaults based on their own WIM data or for specific analysis purposes. In addition, this guide contains an operator's manual that supports the use of the LTPP PLUG software. This software helps users select site-specific or default axle loading conditions from its traffic loading library and produces axle load distribution input files for use with the MEPDG or DARWin-ME software. The software can be used to store, view, and group multiple normalized axle load spectra (NALS) and to develop MEPDG inputs and defaults using agency-provided data.

Jorge E. Pagán-Ortiz
Director, Office of Infrastructure
Research and Development

 

Notice

This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document.

The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of the document.

Quality Assurance Statement

The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement.

 

Technical Report Documentation Page

1. Report No.

FHWA-HRT-13-089

2. Government Accession No. 3 Recipient's Catalog No.
4. Title and Subtitle

Long-Term Pavement Performance Pavement Loading User Guide (LTPP PLUG)

5. Report Date

October 2013

6. Performing Organization Code
7. Author(s)

O.I. Selezneva and M. Hallenbeck

8. Performing Organization Report No.

 

9. Performing Organization Name and Address

Applied Research Associates, Inc.
7184 Troy Hill Drive, Suite N
Elkridge, Maryland 21075-7056

10. Work Unit No. (TRAIS)

11. Contract or Grant No.

DTFH61-02-C-00138

12. Sponsoring Agency Name and Address

Office of Infrastructure Research and Development
Federal Highway Administration
6300 Georgetown Pike
McLean, Virginia 22101-2296

13. Type of Report and Period Covered

 

14. Sponsoring Agency Code

 

15. Supplementary Notes

Contracting Officer’s Technical Representative (COTR): Larry Wiser, HRDI LTPP Data Analysis Contract

16. Abstract

This guide addresses the selection and use of axle loading defaults for Mechanistic-Empirical Pavement Design Guide (MEPDG) applications. The defaults were developed based on weigh-in-motion (WIM) data from the Long-Term Pavement Performance (LTPP) Special Pavement Study (SPS) Transportation Pooled Fund Study (TPF). The guide consists of two parts. The first part provides guidelines for selecting and using LTPP SPS TPF axle loading defaults with the MEPDG and DARWin-ME software. These defaults provide a source of axle loading information for pavement analysis for locations where site-specific axle load spectra are not available. The second part of the guide provides practical guidelines that States and LTPP can use to generate additional MEPDG traffic loading defaults based on their own WIM data or for specific analysis purposes. In addition, this guide contains an operator’s manual that supports the use of the LTPP PLUG software. This software helps users select site-specific or default axle loading conditions from its traffic loading library and produces axle load distribution input files for use with the MEPDG or DARWin-ME software. The software can be used to store, view, and group multiple normalized axle load spectra (NALS) and to develop MEPDG inputs and defaults using agency-provided data.

17. Key Words

Long-term performance, Transportation Pooled Fund Study, Mechanistic-Empirical Pavement Design Guide, weigh-in-motion, load spectra

18. Distribution Statement

No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161.

19. Security Classification
(of this report)

Unclassified

20. Security Classification
(of this page)

Unclassified

21. No. of Pages

98

22. Price
Form DOT F 1700.7 Reproduction of completed page authorized

 

SI* (Modern Metric) Conversion Factors

TABLE OF CONTENTS

 

LIST OF FIGURES

Figure 1. Equation. Computation of RPPIF statistics.
Figure 2. Screen capture. Selection of necessary library references
Figure 3. Screen capture. Main menu for selecting different actions
Figure 4. Screen capture. Data import form for importing traffic data summaries
Figure 5. Screen capture. Select NALS source form for selecting loading inputs for MEPDG
use

Figure 6. Screen capture. Review and generation of MEPDG input files for site-specific
NALS

Figure 7. Screen capture. Review of site-specific NALS
Figure 8. Screen capture. Manual selection and generation of MEPDG input files using
default NALS

Figure 9. Screen capture. Review of manually selected default NALS
Figure 10. Screen capture. Assisted, interactive assignment of default NALS
Figure 11. Screen capture. Review of user-defined NALS
Figure 12. Screen capture. View, group, and combine NALS from multiple WIM sites
Figure 13. Screen capture. Compute and record user-defined NALS.

LIST OF TABLES

Table 1. Summary of NALS cluster groups representing different loading conditions by
vehicle class and axle type

Table 2. Summary of axle loading categories by weight for different axle types
Table 3. Description of alternative Class 4 axle loading conditions
Table 4. Description of alternative Class 5 axle loading conditions
Table 5. Description of alternative Class 6 axle loading conditions
Table 6. Description of alternative Class 7 axle loading conditions
Table 7. Description of alternative Class 8 axle loading conditions
Table 8. Description of alternative Class 9 axle loading conditions
Table 9. Description of alternative Class 10 axle loading conditions
Table 10. Description of alternative Class 11 axle loading conditions
Table 11. Description of alternative Class 12 axle loading conditions
Table 12. Description of alternative Class 13 axle loading conditions
Table 13. Global default APC based on 26 SPS TPF sites
Table 14. Distribution of axle spacing on tractor units for FHWA classes 8 through 13
Table 15. Distribution of axle spacing by vehicle class using sample of SPS TPF WIM data
Table 16. Average axle spacing for multi-axle groups
Table 17. Example of computing dominant truck classes
Table 18. Pavement performance impact factors, Wij
Table 19. Example of traffic design conditions for each vehicle class
Table 20. Difference in RPPIF per axle likely to cause change in pavement performance.
Table 21. Field names and descriptions for ALF_DEFAULT_ALS
Table 22. Field names and descriptions for ALF_Gen_Axle_Group
Table 23. Field names and descriptions for DEFAULT_AxlesPerTruck
Table 24. Field names and descriptions for DEFAULT_NALS
Table 25. Field names and descriptions for LTPP_CODES
Table 26. Field names and descriptions for PLUG_LEF_FOR_ESAL
Table 27. Field names and descriptions for PLUG_W_FACTORS_FOR_RPPIF
Table 28. Field names and descriptions for SITE_SPECIFIC_AxlesPerTruck
Table 29. Field names and descriptions for SITE_SPECIFIC_NALS
Table 30. Field names and descriptions for SITE_SPECIFIC_NVCD
Table 31. Field names and descriptions for USER_DEFINED_NALS
Table 32. Field names and descriptions for XMLGen_AxleLoadDistribution
Table 33. Field names and descriptions for XMLGen_AxleLoadMain_Template
Table 34. Field names and descriptions for
XMLGen_DEFAULT_NALS_By_Loading_Cluster

 

LIST OF ABBREVIATIONS AND ACRONYMS

AADTTAverage Annual Daily Truck Traffic
AASHTOAmerican Association of State Highway and Transportation Officials
APCAxle-per-Truck Coefficient
ASTMASTM International (formerly American Society for Testing and Materials)
AVCAutomated Vehicle Classification
DOWDay-of-the-Week
ESALEquivalent Single-Axle Load
FHWAFederal Highway Administration
GPSGeneral Pavement Studies
IInterstate
JPCPJointed Plain Concrete Pavement
LTPPLong-Term Pavement Performance
MEPDGMechanistic-Empirical Pavement Design Guide
MPOMetropolitan Planning Organization
NALSNormalized Axle Load Spectra
NCHRPNational Cooperative Highway Research Program
PLUGPavement Loading User Guide
QAQuality Assurance
QCQuality Control
RANALSRepresentative Annual Normalized Axle Load Spectra
RPPIFRelative Pavement Performance Impact Factor
RVRecreational Vehicle
SHRPStrategic Highway Research Program
SPSSpecific Pavement Studies
TPFTransportation Pooled-Fund (study)
TWRGTruck Weight Road Group
WIMWeigh-in-Motion

 


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The Federal Highway Administration (FHWA) is a part of the U.S. Department of Transportation and is headquartered in Washington, D.C., with field offices across the United States. is a major agency of the U.S. Department of Transportation (DOT). Provide leadership and technology for the delivery of long life pavements that meet our customers needs and are safe, cost effective, and can be effectively maintained. Federal Highway Administration's (FHWA) R&T Web site portal, which provides access to or information about the Agency’s R&T program, projects, partnerships, publications, and results.
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