Traffic Stream Modeling under Heterogeneous Traffic Conditions

Traffic stream models provide relationship among the three basic macroscopic traffic stream characteristics namely traffic speed, volume and density. Traffic stream models are the basic building blocks of traffic flow modeling, design of road systems and traffic management systems. A number of research papers are available proposing different traffic stream models. However, majority of them are based on homogeneous traffic conditions and they may not be directly suitable for the Indian traffic condition. Not much research has been done on this important aspect so far in India. The present study is an attempt to develop a traffic stream model suitable for the heterogeneous traffic flow condition, such as the one existing in India, taking Chennai as case study. Traffic data for the present study are collected using video graphic technique. Flow, speed and occupancy are manually extracted from collected videos and density estimated using the relation connecting occupancy and density. The results show an exponential speed-density relation and parabolic relations for the other two.