Development of Model for Estimating Capacity of Roads for Heterogeneous Traffic Condition in Urban Area

Abstract

The traffic is increased enormously due to rapid growth of vehicle ownership and increase of population in
the urban area of India. The traffic management becomes very difficult due to higher growth rate of vehicles and nonavailability of sufficient space in urban area. It leads to congestion, excessive delay and accidents on urban roads.
Capacity is a key parameter for planning, design and operation of any type of urban roads. Indian Road Congress has
recommended that Level of Service ‘C’ should be adopted for design of the urban roads. It is necessary to develop the
mathematical model for estimating capacity of urban roads considering width of urban roads, traffic composition and
other important parameters in existing condition. In the present study, the speed – flow relationships are developed for
various mid-block sections of urban roads of Ahmedabad city. The capacity is determined for selected mid-block
sections and compared with capacity recommended by IRC:106-1990. The mathematical models are also developed
using multiple regression techniques and validated using statistical tools. The developed models are useful for
determining the capacity of urban roads considering width of road, space mean speed, traffic composition of two
wheelers, auto and cars and bus. It is observed from study that the recommended value of capacity, determined based
on design service volume, suggested by Indian Road Congress (IRC) is less than the actual determined at field.