双层车辆段上盖建筑振动与结构噪声预测分析

Prediction and analysis of vibration and structural noise of upper cover building of double-deck depot

为研究地铁列车在双层车辆段运行引起的上盖建筑振动及室内结构噪声特性,以国内某双层车辆段上盖物业工程为研究对象,采用现场实测和数值模拟相结合的方法,系统分析了双层车辆段上盖建筑振动与辐射二次结构噪声传递规律。基于大地-车辆段-上盖建筑有限元模型,分析了列车荷载作用下,运用库上盖建筑的振动传递特性,再利用声传递向量法分析了上盖建筑室内结构辐射噪声及其特性,最后对室内各板件的噪声辐射贡献度及吸声平板降噪效果进行了研究。分析结果表明:由于高频振动经过土体衰减迅速,在80 Hz以上频段,二层行车引起的上盖建筑底层振动显著大于一层行车;运用库车致上盖建筑振动在第10层衰减至最低水平,随着楼层的继续增加,振动出现放大现象;在40 Hz处天花板和地板对卧室场点声学贡献度最大,其中在顶层采用吸声材料后的降噪效果最为明显。

Here,to study characteristics of upper cover building vibration and indoor structure noise caused by subway train running in double-deck depot,taking upper cover real estate project of a certain domestic double-deck depot as the study object,transmission laws of vibration and radiated secondary structure noise of upper cover building of double-deck depot were systematically analyzed with combination of online measurement and numerical simulation.Based on finite element model of ground-depot-upper cover building,vibration transmission characteristics of upper cover building under train load were analyzed,and then radiation noise and its characteristics of upper cover building indoor structure were analyzed by using the acoustic transmission vector method.Finally,noise radiation contributions of indoor panels and denoising effect of sound-absorbing plate were studied.The analysis results showed that due to rapid attenuation of high-frequency vibration through soil body,ground floor vibration of upper cover building caused by train running in second floor is significantly larger than that caused by train running in first floor within the frequency band above 80 Hz;because upper cover building vibration caused by use of depot trains attenuates to the lowest level when it is transmitted to the 10th floor,with continuous increase in floors,this vibration has amplification phenomenon;at 40 Hz,ceiling and floor board have the largest acoustic contributions to bedroom site points,and the denoising effect is the most obvious when sound-absorbing materials are used on top floor.