Road traffic noise prediction models: a review

Abstract

The environmental quality of our cities is gradually degrading by an incessant growth in the number of vehicles and the ever expanding road network, resulting in the increase of road traffi c noise. Managing road traffi c noise is a challenging task for environmental managers and urban planners. Urban planners often have to rely on road traffi c noise prediction models for their assessment. A critical review of various traffi c noise studies and the number of traffi c noise prediction models cited in literature reveals that they describe the temporal and spatial distribution of traffi c noise. Most of these models are either deterministic or statistical in nature. This article presents a critical review of some of these models. Keywords: ASJ model and GIS model, CoRTN model, FHWA model, FHWA TNM model, RLS90, Stop-and-go model. Road traffi c noise has become a major concern of communities living in the vicinity of major highway corridors. It is causing more disturbances to people than any other sources. Moreover, this menace to health and quality of life has been increasing over the last two decades for number of reasons (1). The most important cause is of the number of road vehicles, and consequently, increases in the density of road traffi c. The construction of multi-lane motorways is going on at increasing rates in most developed countries and even in many developing nations during last few decades, allowing large volume of traffi c to travel at a sustained speed. The next most important cause of noise on the roads is the speed of traffi c. As a general rule, faster the traffi c moves, greater is the volume of noise (2). Surveys conducted in many countries have shown that traffi c noise is one of the principal environmental nuisances in urban areas, and most of the countries have their own traffi c noise prediction model according to the traffi c and environmental conditions. Traffi c noise prediction models are required as aids in the design of highways and other roads and sometimes in the assessment of existing or envisaged changes in traffi c noise conditions. They are commonly needed to assess noise levels set by government authorities. Environmental laws require the Environmental Impact Statement (EIS) to take into account the effect of the proposed noise on all existing and potential elements of the environment, besides statutory criteria. This calls for a variety of descriptors and criteria. Special descriptors are sometimes required for the assessment of complaints about road traffi c noise (3). Traffi c noise prediction models are required for use by fimain groups, viz.,