Noise Investigation and Modelling of Urban Traffic Under Dynamic Conditions

Abstract

Noise pollution as an environmental concern has lately found a lot of attention amongst environmentalists, engineers and general public. There are different sources of noise in the environment like traffic noise: rail, road and aircraft, use of loudspeakers during weddings and religious functions and machinery noise: industry or construction machinery. Vehicular traffic noise (emanating from vehicles plying on the roads) is a major contributor to the overall noise in the environment to which the general population is exposed. The number of vehicles on the roads (especially two-wheelers and cars) has been increasing relentlessly with growing population, demand, affordability and purchasing power. The high traffic noise levels have adverse health effects on the human population. Thus, it is imperative for the town planners and transport engineers to consider the noise aspect at the conceptual stage of the design of urban roads, residential and commercial buildings and market areas. Traffic noise prediction models help in the assessment of noise levels at the initial design stages and later stages when modifications are planned. They are also useful for environmental impact assessment (EIA) studies. The present work describes the urban traffic noise problem with respect to the high noise levels present on the Indian roads, by taking the Patiala city as a representative case. The existing noise levels were assessed at various locations on the city roads by using the standard measuring equipment and procedure. The measurements revealed that the existing noise levels are much higher than the prescribed limits. A Graph Theoretic (GT) approach which is a systems approach has been used to develop a new traffic noise model and also to propose a new traffic noise descriptor. An Urban Traffic Noise System (UTNS) has been proposed which consists of the subsystems: road traffic subsystem, human subsystem, environment subsystem, traffic network subsystem and urban prosperity subsystem.