The Analytic Study Of Noise Model In Prediction And Evaluation Of Traffic Noise

Noise pollution,water pollution,air pollution and solid waste pollution are called the four major pollutions of contemporary society.And noise pollution has attracted a great deal of public attention due to its extensiveness,instantity,and uncontrollability.Traffic noise pollution is one of the major factors of noise pollution.There is no doubt that acoustic environmental impact assessment plays an indispensable role to control traffic pollution effectively before the road construction,which can provide a scientific basis for the prevention and control of subsequent noise pollution,and help to build a better living environment.Therefore,it is an urgent need for the relevant departments to establish an accurate and practical road traffic noise prediction model.The traffic flow-based noise prediction model,which is based on the idea of the highway(traffic)transportation noise prediction model recommended in "Technical Guidelines for Environmental Impact Assessment-Acoustic Environment"(HJ2.4-2009),is established suitable for the evaluation area.Firstly,this noise prediction model is used to evaluate the sound environment impacts of Pingan Street and Nanyuan Avenue in the evaluation area,and pollution prevention measures are proposed.Then,the prediction value is compared with the theoretical value to explore the accuracy of the prediction model.At last,the noise value of Pingan Street after opening to traffic is monitored to analyze he distribution and attenuation of regional noise,which is compared with the predicted value,and put forward the optimization and correction suggestions for the parameter selection,background value and forecast result in the prediction process.The main conclusions are as follows:(1)Through the noise prediction of Pingan Street and Nanyuan Avenue,the following conclusions have been drawn: the day and night noise values of the sensitive points along Pingan Street meet the Class 2 and Class 4a of the "Acoustic Environmental Quality Standard"(GB3096-2008).The day noise values in forecast years of the sensitive point along Nanyuan Avenue satisfies Class 2 of the "Acoustic Environmental Quality Standard"(GB3096-2008),however,the short-term nighttime noise value exceeds 0.1dB(A),the mid-term night exceeds 1.5dB(A),and long-term value exceeds 1.6dB(A).In response to the exceeding of sensitive spots on Nanyuan Avenue,the first row of households are proposed to add double-layer soundproof window to control noise pollution.(2)The significant difference between the predicted value and the theoretical value is tested.The test result was P>0.05,so there is no significant difference between the two groups,and the prediction result is feasible.Through SPSS software,the conclusion that the correlation coefficient between the large-scale vehicles flowrate and noise is the largest.(3)Through measurements of road traffic noise in the study area,it is found that the road traffic noise value gradually decreased with the increase of the horizontal distance,and within 40 m from the centerline of the road,the noise value decrease most significantly.However,the vertical direction noise value shows a trend of increasing first and then decreasing.(4)By comparing the predicted value with the actual measured value,it is found that the measured values are all lower than the predicted values,the maximum error is 7.7dB(A),the minimum error is 0.8dB(A),and the average error is 2.6dB(A).Then the lane model,the average radiated sound level,road bending and obstacles are modified,describing the important impact of background value,and given the correction results.Finally,the results are verified: the maximum error was 1.6d B(A),the minimum error is 0.8dB(A),the average error is 1.2dB(A),and the error range is controlled within 2dB(A),which indicates that the accuracy of the noise prediction model meets the requirements,and it has certain use value.