Effect of Gradient and Its Length on Performance of Vehicles under Heterogeneous Traffic Conditions

Abstract

Study of the basic traffic-flow characteristics and clear understanding of vehicular interaction are the prerequisites for highway capacity and level of service analyses and to formulate effective traffic regulation and control measures. Computer simulation has emerged as an effective technique for modeling traffic flow and to study the flow characteristics over a wide range of roadway and traffic conditions due to its capability to account for the randomness related to traffic. This paper is concerned with application of a simulation model of heterogeneous traffic flow, named HETEROSIM, to quantify the vehicular interaction, in terms of passenger car unit (PCU), for the different categories of vehicles, by considering the traffic flow of representative composition, on up-grades of different magnitudes for intercity roads in India. The PCU estimates, determined through microscopic simulation, for the different types of vehicles in heterogeneous traffic, for a wide range of grades and traffic volumes, indicate that the PCU value of a vehicle significantly changes with change in traffic volume and magnitude of grade and its length.