Testing and Modeling Practices for Implementing a Pavement Friction Management Program

FHWA Technical Advisory T5040 provides information and guidelines for implementing a pavement friction management program (PFMP), which helps state DOTs refine their friction testing practices and places a greater emphasis on the relationship between crashes and pavement friction to minimize friction-related crashes. In the case of macrotexture, NCHRP Report 964 describes the protocols for network-level macrotexture measurements. However, one of the key components of any PFMP is the network safety analysis. For such an analysis, a functional relationship between crashes (or crash risks) and skid resistance is needed, i.e., a safety performance function (SPF) that uses friction and/or texture as one of the safety predictors. To develop SPFs, agencies may use different crash and safety performance metrics (e.g., a wet/dry crash ratio, wet crash frequencies, the type and severity of the crash, etc.) as well as specifying different time windows over which to analyze the crashes. Moreover, depending on the crash reports and the structure of the database, the crash metric used may correspond to one or two traffic directions. Finally, the model structure defined for the SPF can differ among DOTs: some utilize the negative binomial model framework described in the Highway Safety Manual (HSM), while others include model coefficients to represent a panel data structure, random effects, spatial correlations, clustering analysis, machine learning, etc. Because of this great variation in defining these components for safety analysis, there is a need to document the different methods and practices used by state DOTs to model safety performance as a function of skid resistance and to integrate this analysis into a comprehensive PFMP. The objective of this synthesis is to document current and anticipated state DOT practices and methods to (1) measure pavement friction and texture; (2) account for friction and texture during associated design processes (e.g., mixture, geometrical, etc.); (3) model the relationship between these parameters and highway safety; and (4) integrate this information into pavement management processes.

Language

  • English

Project

  • Status: Proposed
  • Funding: $55000
  • Contract Numbers:

    Project 20-05, Topic 56-17

  • Sponsor Organizations:

    National Cooperative Highway Research Program (NCHRP) Synthesis

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC    20001

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Harrigan, Edward

  • Start Date: 20240528
  • Expected Completion Date: 0
  • Actual Completion Date: 0

Subject/Index Terms

Filing Info

  • Accession Number: 01920221
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 20-05, Topic 56-17
  • Files: TRB, RIP
  • Created Date: May 30 2024 4:23PM