Criteria for Restoration of Longitudinal Barriers, Phase II

In NCHRP Project 22-23, “Criteria for the Restoration of Longitudinal Barriers,” researchers surveyed the states to determine what, if any, formal guidelines they have for the maintenance of guardrails. The research determined that while some states did have guidelines for evaluating existing guardrails to determine whether maintenance was warranted, these guidelines were typically based on judgment and were not supported by underlying research. NCHRP Report 656: Criteria for Restoration of Longitudinal Barriers (a product of Project 22-23) provides guidance to assist maintenance personnel in identifying levels of damage and deterioration to longitudinal barriers that affect operational performance. The researchers evaluated 11 damage modes (including damage due to crashes, environmental deterioration, and other causes) commonly associated with the standard strong steel post W-beam (modified G41S) guardrail; they evaluated these modes through a combination of component testing, pendulum testing, finite element simulation, and full-scale crashtesting. The report includes recommendations for additional research to address additional damage modes for barriers. Similar maintenance guidelines for cable barriers are publicized in NCHRP Report 711, Guidance for the Selection, Use, and Maintenance of Cable Barrier Systems, a product of NCHRP Project 22-25, "Development of Guidance for the Selection, Use, and Maintenance of Cable Barrier Systems.” The objective of this research was to develop more comprehensive guidance to assist maintenance personnel in determining the extent of damage to semi-rigid longitudinal barriers that affects operational performance. The guidance may cover additional strong steel post W-beam guardrail failure modes or other types of longitudinal barriers.


  • English


  • Status: Completed
  • Funding: $300000
  • Contract Numbers:

    Project 22-28

  • Sponsor Organizations:

    National Cooperative Highway Research Program

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

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Performing Organizations:

    Roadsafe LLC

  • Principal Investigators:

    Ray, Malcolm

  • Start Date: 20120102
  • Expected Completion Date: 20150630
  • Actual Completion Date: 20150630

Subject/Index Terms

Filing Info

  • Accession Number: 01779273
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 22-28
  • Files: TRB, RIP
  • Created Date: Aug 23 2021 3:23PM