Evaluation of HERO-Coordinated Ramp Metering Installation at M1 and M3 Freeways in Queensland, Australia

Abstract

The recently developed traffic-responsive feedback control strategy HERO (heuristic ramp metering coordination), which coordinates local ramp-metering actions in freeway networks, was implemented on the M1 and M3 freeways in Queensland, Australia. HERO employs an extended version of the feedback regulator ALINEA at the local level; it outperforms uncoordinated local ramp metering and approaches the efficiency of sophisticated optimal control schemes. HERO has been implemented by the Department of Transport and Main Roads of the State of Queensland at six on-ramps of the M1 and M3 freeways. The results show significant improvements in traffic throughput and travel times compared with the previously used fixed-rate ramp-metering system. A rapid economic benefit analysis determined a benefit–cost ratio of 13.8:1 at a 7% discount rate and, therefore, an extremely strong economic merit for the implementation of HERO. The economic payback period for the capital expenditure on this pilot is approximately 4 months.