Risk Analysis of Objects Placed Within the Working Width of Barrier Systems

Barriers deform and deflect when struck by vehicles, so designers provide a clear area behind the barriers to accommodate this movement. The dimensions of this expected deflection zone, referred to as the working width, are typically determined through computer modeling and crash testing under the American Association of State and Highway Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH) impact conditions. The working width represents the maximum lateral penetration of either the MASH test vehicle or the barrier beyond the front face of the barrier. In practice, however, most real-world impacts are less severe than MASH impact conditions and do not require the full working width to shield natural or man-made obstacles behind barriers. Furthermore, site constraints often make it impractical to relocate obstacles outside the working width. Developing a method to measure the potential for impacts with obstacles within a barrier’s working width could help state departments of transportation (DOTs) save both time and project costs. Research is needed to develop a tool that quantifies the potential of impact(s) with a roadside obstacle based on placement of the obstacle within the working width of the barrier. Such a tool would consider impact conditions, barrier deflection behavior, and obstacle placement within the working width. Characteristics such as obstacle type, barrier length, and average annual daily traffic (AADT) are beyond the scope of this research effort. OBJECTIVE: The objective of this research is to develop a tool to measure the potential for impacts with obstacles located within a barrier’s working width based on various impact conditions.

• Record URL:
  • http://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp?ProjectID=5887
• Supplemental Notes:
  • Contract to a Performing Organization has not yet been awarded.

Language

• English

Project

• Funding: $500,000.00
• Contract Numbers:

  Project 22-69

• 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
• Project Managers:

  Turner, Anne-Marie

• Start Date: 20250801
• Expected Completion Date: 0
• Actual Completion Date: 0

Subject/Index Terms

• TRT Terms: Crash tests; Risk assessment; Traffic barriers; Width
• Subject Areas: Design; Highways; Planning and Forecasting; Safety and Human Factors;

Filing Info

• Accession Number: 01955924
• Record Type: Research project
• Source Agency: Transportation Research Board
• Contract Numbers: Project 22-69
• Files: TRB, RIP
• Created Date: May 26 2025 9:48PM