Hale, David K.; Jiaqi Ma; Amir Ghiasi; Pascal Volet; Burak Cesme; Alexandra Kondyli; Bastian Schroeder; Sonika Sethi; Laura Torres; and Francois Belisle
Benefit Summary HTML

To identify and assess potential mobility benefits from alternative design and control strategies at freeway merge and diverge locations, researchers conducted microsimulation studies of freeway locations from different states in 2017-2018. Strategies assessed included both geometric modifications as well as simulated applications of the following control strategies:

  • Mainline Metering - dynamic signal control of mainline traffic under congested low speed operations
  • Coordinated Ramp Metering - feedback-based ramp metering control using both upstream and downstream data, such as the Heuristic Ramp Meeting Coordination (HERO) algorithm
  • Speed Optimization via dynamic traffic calming devices - dynamic variable speed limit signs or other measures to achieve medium free-flow speeds (e.g., 30 miles per hour) near ramp locations
Created Date
Hyperlink Exit Door
Other Reference Number
Report No. FHWA-HRT-20-008
Publication Sort Date
Prepared by Leidos, Inc. for Federal Highway Administration
Result Type
Alternative Designs to Alleviate Freeway Bottlenecks at Merging, Diverging, and Weaving Areas
Project Category
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