Development of Methods to Evaluate Side Impacts for Next Edition MASH

Each year, roadway departure crashes in the United States result in serious injuries and fatalities. Between 2012-2014, the average number of fatalities per year resulting from roadway departure crashes was 18,355. (Source: Fatal Analysis Reporting System, NHTSA). Side impacts of vehicles into roadside hardware are a growing public safety problem. In particular, side impacts with guardrail account for 22 percent of fatalities in passenger vehicle-guardrail crashes (Source: Gabler and Gabauer, 2007). The occupant of a passenger vehicle that side impacts a guardrail has a 30 percent higher probability of being fatally injured than the occupant of a car involved in a frontal impact into a guardrail. Many roadside safety features (e.g., terminals, guardrail end treatments, crash cushions, and luminaire and sign supports) are designed to break away under the loads which are typical of a frontal impact. However, side impacts by non-tracking vehicles may not have enough force to engage the breakaway mechanisms of these features. Because the side of a vehicle, unlike the front, has less structure and crumple zone, side impacts can result in especially severe injuries. To date, however, no substantive improvements have been made to the performance of roadside safety features during vehicle side impacts. NCHRP Report 350 provided side impact test and evaluation procedures for informational purposes; however, there are no recommendations or requirements for side impact crash testing of roadside hardware. More recently, the NCHRP Report 350 appendix for side impact test and evaluation procedures was not included in the AASHTO Manual for Assessing Safety Hardware (MASH) crash test procedures. Little is known about how Report 350- or MASH- compliant hardware performs in side impact crashes. No research to date has developed a comprehensive approach for evaluating roadside hardware under side impact conditions. The development of methods for evaluating these crashes would lead to improvements in roadside safety hardware and improved safety of the motoring public. Results of this research will enable transportation agencies to set and evaluate its level of safety risk and use quantitative information in the decision-making process. The objectives of this research are to develop recommended test procedures considering critical Test Level 3 vehicles to effectively measure vehicle side impacts, and validate/verify the test procedures. This research shall focus on terminals; however, additional roadside safety devices should also be identified and considered. A combination of vehicle simulation and testing, such as, but not limited to, full scale, or pendulum testing is envisioned as part of this research. The research results are intended for inclusion as a new chapter or supplement in a future edition of the Manual for Assessing Safety Hardware (MASH). The research results will also include recommendations for future edition enhancements of the Roadside Design Guide (RDG).


  • English


  • Status: Proposed
  • Contract Numbers:

    Project 22-32

  • 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 Aviation Administration

    800 Independence Avenue, SW
    Washington, DC  United States  20591
  • Project Managers:

    Bush, Mark

  • Start Date: 20171128
  • Expected Completion Date: 0
  • Actual Completion Date: 0
  • Source Data: RiP Project 40857

Subject/Index Terms

Filing Info

  • Accession Number: 01599004
  • Record Type: Research project
  • Source Agency: Transportation Research Board
  • Contract Numbers: Project 22-32
  • Files: TRB, RiP
  • Created Date: May 12 2016 1:00AM