Applications of Variable Speed Control for Contending with Recurrent Highway Congestion

This research project developed vital operational guidelines for design of a variable speed limit (VSL) system and its integrated operations with ramp metering control in contending with recurrent highway congestion. The developed guidelines can serve as an effective tool for traffic engineers to determine when to activate a VSL control and under what traffic conditions it needs to be supplemented by ramp metering operations to ensure the stability of traffic evolution over the congested highway segment. This report also presents various measures of effectiveness for evaluating the benefits of VSL and its integration with ramp metering control. A VSL control algorithm to compute the time-varying speeds in real time, based on detected traffic conditions, was developed in this study. Extensive simulation experiments, calibrated with the field data from US100 in Maryland, were conducted to evaluate the effectiveness of the developed VSL algorithm. Both the experimental results and sensitivity analyses with respect to key model parameters confirmed that proper implementation of VSL can indeed mitigate the congestion caused by the high-speed variance among vehicles and allow traffic flows to better utilize the available roadway capacity.

  • Record URL:
  • Supplemental Notes:
    • This document was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
  • Corporate Authors:

    Mid-Atlantic Universities Transportation Center

    Pennsylvania State University
    201 Transportation Research Building
    University Park, PA  United States  16802-4710

    University of Maryland, College Park

    College Park, MD  United States  20742

    Research and Innovative Technology Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Franz, Mark L
    • Chang, Gang-Len
  • Publication Date: 2014-7-21


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 94p

Subject/Index Terms

Filing Info

  • Accession Number: 01531517
  • Record Type: Publication
  • Report/Paper Numbers: UMD-2012-03
  • Contract Numbers: DTRT12-G-UTC03
  • Created Date: Jul 22 2014 3:04PM