中文摘要：

交通荷载引起的桥梁振动辐射低频噪声为环境噪声污染的重要来源,分析该低频噪声声场分布特性对评价环境噪声污染程度提供重要依据。结合车桥耦合振动理论和声传播理论,建立了车桥耦合振动辐射低频噪声问题的边界元法求解体系,结合一座钢桥面板连续梁桥,对交通荷载作用下桥梁振动产生的低频噪声声场进行了实验分析和数值模拟,并考察了地面的声反射作用对桥梁附近声场分布和声压水平的影响。分析结果表明,边界元方法用于评价车桥振动辐射低频噪声问题具有较好的适用性和较高的精度,并且能够很好地反映声场在空间的分布规律。算例中的钢桥面板梁桥在车辆荷载作用下由振动引起的低频噪声声压水平与测点距离桥面的距离相关,桥面下方和上方的声压分布规律及水平相似。地面声反射对桥面附近声场的影响显著,考虑地面声反射时,地面与桥面间的距离是影响声压水平的重要因素。

英文摘要：

Low-frequency noise induced by vehicle-bridge coupling vibration is an important pollution source for environment.The investigation for the sound field distribution of such kind of noise offers important accordance for assessment of environmental noise pollution.Based on the theories of vehicle-bridge coupling vibration and sound wave propagation,the low-frequency noise due to vehicle-bridge coupling vibration is investigated using boundary element method（BEM）.A steel bridge in service is studied as a case.The low-frequency noise produced by vehicle-bridge coupling vibration is investigated by experiment and numerical simulation.And the effects of sound wave reflection due to the ground surface on sound field distribution and sound pressure is also investigated.Results show that the applicability and precision of BEM are great in assessment of low-frequency noise due to bridge vibration.And the distribution of sound field is obtained.For the steel plate girder bridge in this paper,the sound pressure of a survey point in sound field is related to the distance between the survey point and the bridge.The sound pressure level in upward side of the bridge is similar to that in downward side.The effects of sound reflection of ground surface on sound field in neighborhood of the bridge deck are great.When considering sound reflection of ground surface,the distance between ground surface and the bridge is an important issue for sound pressure due to bridge vibration.