高架道路全封闭及半封闭声屏障降噪效果分析

Analysis of Noise Reduction Effect of Fully and Semi-closed Noise Barriers on Elevated Road

为研究不同型式声屏障在降低交通噪声中的作用和差异,并为交通工程环境影响预测及声屏障的设计提供参考依据,文章以温州市某高架桥为例,对全封闭及半封闭声屏障降噪效果进行监测及数据分析,结果表明,在全封闭声屏障外21 m处的昼间降噪量为15.1~17.2 dB(A),夜间降噪量为10.0~12.3 d B(A);声屏障外54 m处的昼间降噪量为0.7~2.2 dB(A),夜间降噪量为3.5~4.6 dB(A)。在半封闭声屏障外40 m内的昼间降噪量为3.5~5.8 d B(A),夜间降噪量为2.5~3.8 dB(A);声屏障外67 m处的昼间监测值有时高于对照点的监测值,说明在城区复杂噪声条件下,半封闭隔声屏障的降噪有效作用范围在65 m左右。对比2种类型的隔声屏障降噪效果差异,当敏感点与高架道路距离在25 m以内时,全封闭声屏障与半封闭声屏障降噪量昼间差值为6.4~8.6 dB(A),夜间差值为4.0~7.3 dB(A);当敏感点与高架道路距离在60 m以上时,全封闭声屏障与半封闭声屏障降噪量昼间差值为-0.5^-2.3dB(A),夜间差值为-0.4~2.5 d B(A)。因此,对于车流量较大的城区高架道路的噪声防治,当声环境敏感目标距离较近且多为高楼时,在经济条件允许的情况下,建议采用全封闭声屏障,其他区域则可根据实际情况采用半封闭声屏障,既可起到降噪效果,又可降低工程投资。

To study the effects and differences of different types of noise barriers in reducing traffic noise,and to provide reference for environmental impact prediction and noise barrier design of traffic engineering,taking an elevated bridge in Wenzhou is an example,the noise reduction effect of fully and semi-closed noise barriers is monitored and analyzed.The results show that the noise reduction of fully enclosed noise barrier at 21 m outside the full enclosed noise barrier of viaduct is15.1~17.2 dB(A)in daytime and 10.0~12.3 d B(A)in night time,the noise reduction of fully enclosed noise barrier at 54 m outside the full enclosed noise barrier of viaduct is 0.7~2.2 dB(A)in daytime and 3.5~4.6 dB(A)in night time.When the semi-enclosed noise barrier is within 40 m outside the noise barrier,the noise reduction in daytime is 3.5~5.8 dB(A)and 2.5~3.8 dB(A)in night time,the daytime monitoring value at 67 m outside the noise barrier is sometimes higher than that at the control point,it shows that the effective range of noise reduction of semi-enclosed noise barrier is about 65 m under complex noise conditions in urban areas.When the distance between the sensitive point and the elevated road is less than 25 m,the difference of noise reduction between full-enclosed and semi-enclosed noise barriers is 6.4~8.6 dB(A)in day time and 4.0~7.3 dB(A)in night time.When the distance between the sensitive point and the elevated road is more than 60 m,the difference of noise reduction between full-enclosed and semi-enclosed noise barriers is-0.5^-2.3 d B(A)in day time and-0.4~2.5 dB(A)in night time.Therefore,for the noise prevention of urban viaducts with large traffic flow,when the acoustic environment sensitive targets are close and mostly tall buildings,it is suggested to adopt full-enclosed noise barrier when economic conditions permit,and semi-enclosed noise barrier can be used in other areas according to actual conditions,which can not only reduce noise,but also reduce investment.