Managed Lane Strategies Feasible for Freeway Ramp Applications

摘要

Current funding constraints and difficulty in gaining environmental and public approval for large-scale construction projects has forced the Texas Department of Transportation (TxDOT) to continue considering alternative solutions to roadway widening to mitigate congestion. One area for potentially improving freeway performance is ramp locations. Current ramp treatments only address point demand. Applying managed lanes operational strategies to ramps could maximize existing capacity, manage demand, offer choices, improve safety, and generate revenue. This project investigates the application of these demand management strategies to mainlane ramps and managed lane ramp operations during the peak period; i.e., managed ramps. Such strategies could include peak-period use of both mainlane or managed lanes entrance and exit ramps by user group, possibly influencing mode choice, enhancing mobility, improving safety in a freeway corridor, and helping ensure the integrity and free-flow operations of a managed lanes facility. This research: (1) investigated under what conditions should managed ramps be considered for both mainlanes and managed lanes based on relevant factors including target users in the corridor, congestion level, ramp spacing/density, ramp volumes, accident history, etc.; (2) assessed the impacts and benefits of managed ramps; and (3) developed general guidelines and best practices for operating and enforcing managed ramps.