高速铁路桥梁声屏障插入损失五声源预测模式研究

研究一种高速铁路桥梁声屏障插入损失的五声源预测模式,可应用于时速300 km以上高速铁路声屏障声学设计。对高速铁路噪声源进行现场辨识测试,分析其声源特性,将高速铁路噪声源简化为轮轨区、车体下部、车体上部、集电系统、桥梁结构5个等效噪声源。根据单声源模式的声屏障插入损失预测公式,结合不同车速下声源等效频率和噪声贡献量,同时考虑桥梁翼板对声传播的影响,形成五声源模式的声屏障插入损失预测公式。采用该方法计算2.15 m声屏障插入损失并与现场测试数据对比,结果显示距离线路25~50 m处受声点插入损失预测结果与实测结果吻合度最高。

Five-noise-source Model for Predicting Insertion Loss of Noise Barrier on High Speed Railway Bridge

This paper studies the five noise sources model for predicting insertion loss of noise barriers on high speed railway bridge. The model can be used for acoustical design of noise barriers for high speed railway above 300 km / h. By noise identification test and analysis,the noise sources are simplified to five effective sources,including wheel / track area,lower part of vehicle,upper part of vehicle,current collecting system and bridge structure. Based on single source model for predicting insertion loss of noise barrier,the formula for five sources model prediction is formed considering the source effective frequency and noise contribution and the effect of wing plate of the bridge on sound propagation. This method is used to calculate the insertion loss of 2. 15 m noise barrier and compare the results with site measurements. The results show that the predicted values best match the measurements at the noise receiving points 25 to 50 m away from the railway line.