Evaluation of pavement noise emission model: A case study in Tehran

Noise pollution and its influence on environment and life quality of human beings may be considered as a hot topic in scientific research. Since there are no sufficient studies on noise pollution in Tehran, this study was carried out to determine noise levels of pavement in Tehran City. SMM1 (The first standard of noise measurement method) model is one of the most common models used in calculating noise emission in Tehran City. Because factors which this model uses are close to Tehran traffic situation, in this study, SMM1 noise emission model has been modified by including pavement statement factor. In other words, the pavement age will affect noise emission in environment. Thus, a case-study is chosen and its pavement statement factor is added to SMM1 noise emission model. Equivalent noise level changes in different distances with sound noise. This effect is calculated and indicated in this paper. Another factor that could affect the sound level is traffic volume, which is also shown in this paper. In this study, it is concluded that when asphalt pavement is fresh and new, equivalent noise level is 2 (dB) less than when the pavement becomes old due to congestion of pavement and its decreasing void. The results showed that pavement noise should be mentioned among the major environmental problems, and studies aim at preventing it should have great priority.