Effect of Side Frictions on Traffic Characteristics of Urban Arterials

The urban transportation system is the hub of all economic activities in urban communities all over the world, and thus sustains livelihood of the people living there. The increase in population has led to increase in vehicular population. The land resources being constant, this vehicular growth has adverse effect on smooth traffic flow. Increase in vehicular population along with shortage of urban road space is manifested in the form of road side frictions. Side friction factors are defined as those activities which take place on the sides of carriage ways or even on the carriage ways that are likely to affect the normal traffic flowing through the carriage ways.The present work aims at analyzing the impact of road side frictions on traffic characteristics of urban roads in India. Study was conducted on urban roads in some of the thickly populated urban cities like Mumbai, Bengaluru and Thiruvananthapuram. The side friction factors were limited to buses stopped at bus stops, pedestrians walking along sides of carriage ways and on-street parking of vehicles. Multiple linear regression analysis was chosen to relate the factors contributing to reduction in speed caused by side friction factors. Reduction in speed was studied for stretches with individual side frictions as well as stretches under the combined effect of all the factors. The result showed that there was significant impact of side friction on vehicular speed on urban roads and could also bring about the extent of impact of individual factors on speed. The results highlight the need to include side friction factors on all traffic related studies for proper planning of urban roads.