STUDY OF MIXED TRAFFIC STREAM PARAMETERS THROUGH TIME LAPSE PHOTOGRAPHY

A review of literature on homogeneous traffic has shown that density, speed and flow are the basic parameters that describe the traffic situation. While extending the same theory to a mixed traffic situation, having a two directional freedom, it was observed that equivalent passenger car unit is a popular method used to convert mixed traffic into an equivalent homogeneous traffic situation. Nevertheless such treatment has not produced satisfactory treatment of heterogeneous traffic stream. It was therefore decided to take up studies to understand the basic behaviour of slow and fast moving vehicles and their interactions in combined traffic situation. For this purpose time lapse photography was found to be a good technique to record the complete information of the complex traffic behaviour. This technique has been chosen for these studies and an analytical procedure has been formulated through a computer programme for retrieving the data efficiently. As a result of detailed analysis, it was found that to describe the two way freedom of slow moving vehicles, the concept of a real density is most appropriate. Several relationships are then examined as this new definition and the results were found encouraging. It is recommended that further work be conducted to examine the applicability of this concept to cover a variety of traffic situations. (Author/TRRL)