The present paper suggests a methodology to analyse speed data on multilane highways, where a normal distribution and other continuous distributions fail to define the speed distribution pattern for traffic streams. The concept of bimodality is introduced to describe the traffic speed behaviour on multilane highways. The speed data collected at 10 different sections of four-lane divided highways in India are analysed and parameters of unimodal and bimodal curves are evaluated. The observed speed data were either unimodal or bimodal depending on the traffic composition at a particular section. Though, the percentage of non-motorized traffic significantly influenced the speed distribution patterns, this and the traffic volume both failed to provide any satisfactory explanation for the observed speed distribution curves. (a) For the covering entry of this conference, please see ITRD abstract no. E217099.
Samenvatting