A flow-maximizing adaptive local ramp metering strategy

An extension of the feedback local ramp metering strategy ALINEA is proposed that allows the automatic tracking of the critical occupancy to help maximize the mainstream flow. The developed AD-ALINEA strategy may be valuable whenever the critical occupancy cannot be estimated beforehand or is subject to real-time change due to changing environmental conditions or traffic composition (e.g. trucks). An upstream-measurement based version of the adaptive strategy (AU-ALINEA) is also developed. Both strategies are successfully tested in a stochastic macroscopic simulation environment under various scenarios.