Microsimulation Study of the Effect of Exclusive Bus Lanes on Heterogeneous Traffic Flow

This paper is concerned with modification and validation of a recently developed microsimulation model of heterogeneous traffic flow and application of the model to study the impact of provision of reserved bus lanes on urban roads. The impact of introduction of an exclusive bus lane is measured in terms of reduction in speed of other categories of motor vehicles, due to the consequent reduction in road space, over a wide range of traffic volume. The main finding of this paper is that if an exclusive bus lane is provided under highly heterogeneous traffic conditions (prevailing in Indian cities), then the maximum permissible volume to capacity ratio that will ensure a level of service of C for the traffic stream comprising all the motor vehicles, except the buses, in a typical eight lane divided urban road (14.5-m-wide road space per direction) is about 0.62. Through this study, a framework for justification of providing exclusive bus lane has also been defined.