DRIVE project V1035 Christiane : a comparison of the RWS-strategy and the ALINEA-strategy for ramp metering at the Coentunnel in Amsterdam

From March 1989 onward the traffic intending to join the A10 was metered on the ramp to RW10 at the Coentunnel in Amsterdam. The aim of ramp metering is to improve traffic flow at the Coentunnel. The metering light on the ramp admits a certain volume of traffic per time period, depending on the traffic situation on the A10. The volume of traffic admitted to RW10 is regulated by the duration of the red period of the metering light. The required red period is derived from the volume and speed of the A10 traffic by means of a metering algorithm. The metering algorithm is part of the RWS metering strategy developed by RWS, Dienst Verkeerskunde (DVK), based on flow upstream and on speed both upstream and downstream of the ramp. The cheaper French ALINEA strategy is based on occupancy which is measured downstream of the ramp. A field trial was carried out with the two metering strategies at the Coentunnel. In this report the data collection and processing are described, as well as the comparison results. Conclusion is that the ALINEA algorithm for ramp metering produces results comparable to or better than those of the RWS algorithm.