Evaluation Study of Inflow Traffic Control by Ramp Metering on Tokyo Metropolitan Expressway

Traffic congestion is a common problem; particularly in metropolitan areas. It is especially true for the Tokyo Metropolitan Freeway (MEX) which handles about 1.2 million vehicles per day. Thirty percent of these vehicles use the MEX central circular and radial routes causing chronic traffic congestion. A traffic-control center in Japan mitigates the congestion by governing access to MEX entrance ramps using empirical methods per 30 minutes; which is reasonable, albeit a static traffic-control strategy. Ramp metering is another effective and dynamic trafficcontrol strategy which is not yet implemented and is examined in this study.