Center for Traffic Simulation Studies

As an efficient traffic control strategy to ameliorate freeway traffic congestion, ramp metering has been successfully applied in the U.S. However, the applicability and effectiveness of a ramp-metering strategy must be investigated during the pre-implementation phase to ensure the success of the implementation. The use of traffic simulation models can provide a quick and cost-effective way to test and evaluate a ramp-metering algorithm prior to implementation on the freeway network. In this paper a micro-simulation laboratory, based on a functionality-enhanced Paramics simulation model that integrates some complementary ATMIS modules, has been established for the evaluation of ramp metering control. Three adaptive ramp metering algorithms, including ALINEA, BOTTLENECK and ZONE, have been evaluated in this Paramics simulation laboratory over a stretch of the I-405 freeway in California. Simulation results show that the two coordinated ramp-metering algorithms, i.e. BOTTLENECK and ZONE perform better that the current fixed-time control and ALINEA algorithm under both morning and afternoon scenarios.