A global comparison of ramp-metering algorithms optimising traffic distribution on motorways and arterials

The objective of this paper is to compare different ramp-metering algorithms in terms of the compromise they establish between delays to traffic on motorways and on arterial roads. Two different types of local ramp-metering were compared: ALINEA algorithm with a feedback philosophy and Demand-Capacity algorithm with a feed-forward philosophy. The main conclusion of this work is that an integrated policy is necessary between motorway and arterial road operators while implementing traffic control policies such as ramp-metering. The choice of a combination of ramp-metering algorithm, green time policy and ramp queue management strategy should consider impacts on the entire road system. This work has also shown that this choice may be different depending on the traffic condition on the motorway and the arterials. Further research can be devoted to developing an algorithm that will identify the best ramp-metering algorithm during a given traffic situation.