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Extension of Safety Assessment Tool for Construction Work Zone Phasing Plans

Status: Complete

Description: Engineering practitioners must balance safety and mobility when evaluating different construction phasing alternatives for highway work zones. There is a need for practitioner guidance and practical tools to assess work zone safety impacts as such resources are currently lacking. The objective of the study was to extend a structured safety assessment tool that was previously developed for freeways, expressways, and rural two-lane highways to include other facilities such as arterials, signalized intersections, unsignalized intersections, multi-lane highways, and ramps. Using Missouri data, this study introduces five new crash prediction models for work zones on urban multi-lane highways, arterials, ramps, signalized intersections, and unsignalized intersections. All the work zone models in this report are proposed for the first time. These work zone models are implemented in a user-friendly spreadsheet tool that automatically selects the appropriate model based on user input. The tool predicts crashes by severity, and computes the crash costs for each construction phasing alternative.

Report: extended_safety_assess_tool_for_WZ_phasing_w_cvr.pdf 7.1 mb (published 2018)

Other Document: Work Zone Safety Assessment Tool 1.3 mb *zip

State conducting research: Missouri


  • Sun, Carlos (University of Missouri, Columbia)
  • Edara, Praveen (University of Missouri)
  • Brown, Henry (University of Missouri, Columbia)
  • Rahmani, Roozbeh (University of Missouri, Columbia)
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