REVIEW OF STUDIES ON TRAFFIC PARAMETERS FOR HETEROGENEOUS CONDITION

Abstract

The traffic circumstances in developing economies are primarily different from that of the developed economies. Traffic density of motorized and non-motorized of two-wheelers and three-wheelers along with numerous other vehicles with no-lane discipline are termed as heterogeneous. This heterogeneous traffic is without a doubt different from the one with the occurrence of trucks which has also been termed as heterogeneous traffic. The concluding is mostly tranquil of passenger cars and can be aptly termed as ‘‘homogeneous’’ traffic, whereas the previous is composed of vehicle types with a wide range of static and dynamic characteristics, which reside in the identical right of way, follow-on in an unsynchronized association of the vehicles. Another individual characteristic of this traffic is the lack of lane-discipline, resultant from the wide difference in sizes and maneuvering abilities of any motorized or non motorized vehicles. These distinctions result in some phenomena like vehicle creeping, which are missing in the homogeneous traffic. Therefore, this type of traffic can be referred to as ‘‘heterogeneous disordered’’ or ‘‘mixed’’ traffic. An evaluation of the literature has shown that most of the studies in such traffic make use of the methods and concepts developed for heterogeneous traffic. A small amount of studies have attempted to capture and understand the distinctive characteristics of the mixed traffic. The main purpose of this paper is to provide a review of the studies on different mixed traffic characteristics in developing economies, identify their limitations and provide guidelines for the future research. In addition, a detailed methodology of the recreation process for the mixed traffic is given, reflecting the ‘‘gap filling’’ rather than the conventional ‘‘car-following’’ behavior. An assessment of the past modeling approaches is also presented and the accuracy of their implementation is discussed.