Studying The Distribution Of Traffic Noise And Environmental Impact On Urban Roads

This paper is selected Xi'an main traffic roads, by means of measurement Leq and octave band spectrum, at the same time, tested the vehicle's speed and counted the traffic flows on the roads. After done six experiments, it finished the data process by Software Excel and Spass. It is shown as follows:1.It was adopted method of AHP to analyze the weight of the impact factors, it. demonstrated that the contribution by a various feature roads for the traffic noise was 34.8%,respectly, the vehicle run status and auto's speed and traffic flows and the scale of traffic flows were 25.5%,24.3%,14.8%,0.4%.2. Among the ten roads, the day's traffic noise are all exceed 4a level standard,100% are polluted by traffic noise,70% roads are heavier pollution,10% are middle and 20% are light. It is shown that the traffic noise pollution in Xi'an City is serious.It is similar frequency feature for all various roads, totally, the noise of octave band spectrum show attenuation. The noise of 63Hz is the highest, the noise of 1000Hz is higher and the noise of 8000Hz is the lowest. From the octave band spectrum, it is focus on middle-low frequency that the pollution of traffic noise.3.The decline characteristic of traffic noise as the distance from sound source shows logarithm decrease, among selected Xi'an City roads, respectively, the distance which come up to the standards by traffic noise day's is 12-20m, night's is 130-735m.4. For car's average speed, they are positive relevance between traffic noise and vehicle speed, the speed bigger and the noise higher, vice versa.When the vehicle is in jam, the vehicle speed is in 0-10 km/h and noise higher.The car speeds Nan-er-Huan Road concentrate on 30-35 km/h, Xi-er-Huan Road's on 20-30 km/h, The car speeds Da-Qing Road and Bei-er-Huan Road distract, mainly respectively on 20-50 km/h,60-70 km/h. The vehicle speed Bei-er-Huan Road higher than others, this is one of reasons that the traffic noise Bei-er-Huan Road is also higher than others.5. It was concluded the relation of the traffic noise versus to vehicle flows and auto's speed and auto's rate.6. At near the distance to two sides residential buildings, the traffic noise impact on is higher.For lower floor of stairs,the noise effect is higher at the 4 and above floor of stairs commonly. For the high rise buildings, the traffic noise is increase quickly lower than 8 floor of stairs, more than 8, noise of the all stairs up and down on extent at 5dB(A) and it shows attenuation.The frequency spectrums by two sides of roads of buildings are similar as traffic noise, at arrange of 31.5-125 Hz, noise are higher, at arrange of 125 Hz-1000Hz, decline stably relatively, the noise frequency spectrums more than 1000Hz, the attenuation of traffic noise increase fast,at the 8000Hz, the traffic noise is the lowest.7. This article put forward reasonable control measures of traffic noise.