Traffic noise is a kind of noise caused by cars, trains and aircraft. Among them, noise produced by cars is the most important factor in cities. According to the National Institute of Environmental Research(NIER)'s survey, Road traffic noise levels in Busan are the highest of all the cities in Korea. So, appropriate measures for road traffic noise reduction is required. For this purpose, the construction of a noise map in Busan will play a vital role. However, road traffic noise formulas are constructed considering regional characteristics such as each country road's environment and vehicle quality. Therefore, prior to constructing a noise map in Busan, examination processes about each formula constituent status and estimation process are required preferentially. In this research, the basic first stage is to estimate Busan's road traffic noise. First, investigate characteristics of each road traffic noise estimate and using this, a noise map is constructed for road traffic noise in Busan. Then the adaptation of a road traffic noise formula is evaluated.

When houses or buildings are adjacent to roads, with no effective prevention of road traffic noise, neighbors are exposed to it. It is important to understand the properties of sound propagation before taking a counter- measure against road traffic noise. It is easy to estimate the properties of sound propagation without obstacles, but very difficult and complex to estimate them with ones. The purpose of this study is to present a useful tool that can estimate the properties of sound propagation. In the beginning of this study, we investigated the attenuation of road traffic noise with two pillar buildings, and presented practical approximate calculation method, and verified that through scale model. The outcomes from this study are as follows : ⑴ Over second reflection sound waves can be ignored. ⑵ Diffraction sound waves that happen when reflection sound and first diffraction wave are projected at the wedge of other building can be ignored.