Development of Operational Performance and Decision Models for Arterial Bus Lanes

Abstract

Bus lanes are a form of exclusive bus facility typically found along busy arterial streets. The use of bus lanes is justified because buses can carry more passengers than automobiles. However, a lane taken away from general-purpose traffic and designated as a bus-only lane can create congestion in other lanes, causing protests by motorists. An effort was undertaken to develop operational performance and decision models that can be used to justify and design bus lanes on arterial streets. The model considers the overall average person travel time under two treatments: with and without a bus-only lane. The CORSIM simulation model was used to estimate the bus and nonbus travel speeds under various scenarios of prevailing conditions, including bus volume, nonbus volume, right-turn volume, bus stop location, bus stop density, presence of bus bay, number of bus berths, mean dwell time, green ratio, cycle length, signal offset, and number of lanes. The simulated data were used as a substitute for field data in an empirical modeling of relationships between travel speeds and the prevailing conditions. The speed models allow person travel times to be estimated under different bus-lane designs and prevailing conditions. The models were found to produce speeds that closely approximate those reported in the literature for the given input conditions.