A Study Of Monitoring And Prediction Of Sound Environmental Effect In The Operation Period Of Rail Transit

Rail transport is not only part of the national infrastructure, but has also the potential to reduce traffic congestion due to urbanization. However, with the continuous development of urban rail transit, noise pollution from railway traffic is becoming an environmental issue affecting people’s daily lives. Consequently, the sustainable development of urban rail transit, along with regulation and control of rail traffic noise pollution are the current problems to be solved.This study focuses on rail traffic noise referring to Hainan East Central Railway as an example, and will include the following aspects:First, the sources and characteristics of the occurring noises of rail traffic were analyzed on possible harm caused, relating to different aspects of rail traffic noise control measures.Second, through field survey and measurement of noise pollution in Haikou City on the Hainan East Central Railway segment studied we obtained the following results:①The horizontal distance. Because of the location of the viaduct above the ground resulting in the source of noise being higher located the noise level increases with distance reaching is maximum at about60m while the impact of noise after this mark decreases with distance.②The vertical distance. Along the high-rise buildings, the noise monitoring results on each floor show that the maximum sound level Lmax gradually increases from the first floor to the third floor to reach the maximum, and then decreases with height; equivalently the average sound level Leq gradually increases from the first floor to the maximum at the fourth floor.③Vegetation Measurement of noise when the train passes on streets with different background found the Leq lower on streets with trees than on tree-free sections. More precisely, it depends on the type and density of trees, we have Leq tree>Leq palm>Leq dens tree with a difference of1dB(A) to0.7dB (A); the same becomes obvious for the maximum sound level with Lmax tree> Lmax coconut> Lmax dense tree. The noise reduction effect of street trees on the road transport system noise is obvious.Third, we study using the model prediction law on sensitive points of the railway system of the East Central Railway in Haikou City, on the example of Nanhai Avenue, short-term (2020) and long-term (2030) noise developments. With the formula relating sound level and noise exposure we found that at Nanhai Avenue about30m from the track, if the hour train makes up to14trips, its daytime average sound level will exceed the70dB(A) standard per hour imposed for the control of noise on this urban section.Fourth, in an effort to understand the subjective perception of the viaduct, particularly the noise caused by the East Central high speed railway, Nanhai Road residents and businesses along the viaduct were interviewed in the form of a questionnaire.In conclusion we can say, that studying the characteristics of the rail traffic noise along with control measures, as well as the noise impact and prediction laws on the example of Hainan East Central Railway, provides a solid basis for the East Central Railway to promote transportation noise control.