论文部分内容阅读
现有的桥梁噪声预测方法大多仅考虑一跨桥梁的噪声辐射而忽略了相邻跨桥梁的影响。提出了预测多跨桥梁低频噪声的方法:首先,通过车辆-轨道-桥梁动力相互作用分析计算了列车通过多跨桥时的桥梁响应;然后,采用2.5维边界元方法获得多跨桥梁的声模态传递向量;最后结合桥梁动力响应和声模态传递向量求得多跨桥梁的总辐射噪声。以某轨道交通U梁为研究对象,对比了采用多跨桥梁模型、单跨桥梁模型的计算声压结果的异同,并与实测值进行比较,明确了在预测远场噪声时必须采用多跨桥梁计算模型。研究表明,多跨桥梁的辐射噪声沿桥梁纵向分布较为均匀,在现场实测时可选取任意横断面位置进行噪声测试。
Existing bridge noise prediction methods mostly only consider the noise radiation of a bridge and neglect the influence of adjacent bridges. A method of predicting the low frequency noise of multi-span bridges is proposed. Firstly, the bridge response of the train passing through the multi-span bridge is calculated through the dynamic analysis of vehicle-track-bridge interaction. Then, the acoustic modes State transfer vectors. Finally, the total radiation noise of multi-span bridges is obtained by combining the dynamic response of bridge and modal transfer vectors. Taking the U-beam of a rail transit as an example, the similarities and differences of calculated sound pressure results of a multi-span bridge model and a single-span bridge model were compared and compared with the measured values to make it clear that multi-span bridges Calculate the model. The research shows that the radiation noise of multi-span bridges is more evenly distributed along the longitudinal direction of the bridge, and any cross-sectional position can be selected for noise measurement during the field test.