Driver Behavior in Left-Turn and Other Two-Vehicle Crashes

During 2012, nearly 3300 crashes involving a vehicle turning left into oncoming traffic occurred in Minnesota, including more than 1100 fatal and personal injury crashes. Many agencies, including the Minnesota Department of Transportation, are interested in using a flashing yellow arrow to implement within-day changes in left-turn (LT) treatment, but this requires being able to predict how the risk of LT crashes varies at particular intersections, as traffic characteristics change during a day. This project has inter-related objectives: (1) to contribute empirical findings regarding LT gap acceptance, the trajectories followed by LT drivers, and a the behavior of drivers involved in LT crashes, and (2) to develop and validate a simulation model of LT crashes that could ultimately be used to predict the safety-related effects of design or operational changes. To accomplish these, the researchers reduced video data of drivers making permitted left turns and characterized both LT gap acceptance and LT turning trajectories. These findings were then incorporated in a prototype LT crash simulation model and the model's predictions were compared to an empirical model of LT crash risk developed in a recently completed MnDOT project. The project also developed methods for quantifying uncertainty in the reconstruction of planar impact crashes and for estimating driver behavior variables from pre-crash data collected from event data recorders.


  • English


  • Status: Active
  • Contract Numbers:



  • Sponsor Organizations:

    Research and Innovative Technology Administration

    University Transportation Centers Program
    1200 New Jersey Avenue
    Washington, DC  United States  20590

    Roadway Safety Institute

    University of Minnesota
    Minneapolis, MN  United States  55455
  • Project Managers:

    Stearns, Amy

  • Performing Organizations:

    University of Minnesota

    Department of Civil, Environmental, and Geo- Engineering
    500 Pillsbury Drive S.E.
    Minneapolis, MN  United States  55455
  • Principal Investigators:

    Davis, Gary

  • Start Date: 20140501
  • Expected Completion Date: 20180630
  • Actual Completion Date: 0
  • Source Data: RiP Project 37489

Subject/Index Terms

Filing Info

  • Accession Number: 01567218
  • Record Type: Research project
  • Source Agency: Roadway Safety Institute
  • Contract Numbers: DTRT13-G-UTC35, CTS-2015021
  • Files: UTC, RiP
  • Created Date: Jun 26 2015 1:00AM