Evaluation of Diverging Diamond Interchanges for Alabama, Phase I

The goal of this research is to develop guidance for the Alabama Department of Transportation (ALDOT) to establish the locations where a diverging diamond interchange (DDI) would be beneficial. The University of Alabama (UA) will assist the University of Alabama - Huntsville (UAH) to perform the proposed research. The objective of this project is to assist on tasks associated with DDI project funded by ALDOT. This will require the subcontractor to run simulations and evaluate alternatives. The DDI, or Double Crossover Diamond (DCD), is a form of interchange design upon which the intersections of the cross-over road and the entrance/exit ramps are constructed to remove all left turns. The benefits of the interchange design stem from the removal of left-turns at the entrance/exit ramp signals, thus reducing the number of phases required improving traffic flow and reducing the number of conflict points improving safety.


  • English


  • Status: Completed
  • Contract Numbers:


    UTCA #12413

  • Sponsor Organizations:

    University of Alabama, Huntsville

    Department of Civil and Environmental Engineering
    Huntsville, AL  United States  35899
  • Project Managers:

    Anderson, Mike

  • Performing Organizations:

    University Transportation Center for Alabama

    University of Alabama
    Tuscaloosa, AL  United States  35487
  • Principal Investigators:

    Jones, Steven

  • Start Date: 20130601
  • Expected Completion Date: 0
  • Actual Completion Date: 20140430
  • Source Data: RiP Project 35169

Subject/Index Terms

Filing Info

  • Accession Number: 01490729
  • Record Type: Research project
  • Source Agency: University Transportation Center for Alabama
  • Contract Numbers: 24327, UTCA #12413
  • Files: UTC, RiP
  • Created Date: Aug 30 2013 1:01AM