Ramp metering control on the junction of freeway and separated connecting collector-distributor roadway

Ramp metering has been emerged as an effective freeway control approach to ensure efficient freeway operations. The performance of ramp metering depends on various factors, such as traffic flow, downstream traffic conditions, and queue override policy. This paper proposes a linear approach for designing local demand-capacity ramp controls using simulation model. This study investigates the macroscopic simulation equation models of ramp metering signal timing plan on the freeway and separated connecting collector-distributor roadway of the junction section on Taiwan National Freeway Systems. The main analysis will be based on these driver behaviors including compulsive lane-changing and about 50% weaving activities on the separated connecting collector-distributor roadway. The ramp metering control is to optimize freeway mainline traffic by providing metering rates for accesses within the control segments. The results of this study show that well-designed ramp metering control not only increase the freeway mainline traffic flows and speed, but also prevents traffic breakdown.