This paper presents an overview of the highway capacity and level of service applications in India. The traffic flows in rural highway sections range from 5000 to 50,000 vehicles per day. The traffic consists of a mix of fast and slow moving vehicles. The highway traffic is observed to be growing at an annual rate of about 7 per cent. The rural highway sections are of two lane carriageways. The mixed nature of traffic and its behaviour on highways pose problems in quantifying the capacity and levels of service. Initially the United States highway capacity standards were adopted with appropriate equivalent passenger car units. The observations in real life reveal that the standards of the United States are standards of the United States are inappropriate and efforts have been made to study the speed-flow relationships through analytical methods and also by developing simulation models. The Indian Roads Congress has evolved tentative capacity and level of service standards and they need revision on the basis of extensive field surveys. The future research efforts are expected to be towards the evolution of simulation models and their application in the determination of highway capacities under mixed traffic conditions. (A)
Abstract