城市轨道交通高架桥影响下的多层建筑振动特性分析

为探究城市轨道交通沿线的多层建筑在列车通过时的振动特性,以某一城市轨道交通高架桥旁的一栋4层楼建筑为研究对象,通过对每一楼层同时进行振动测试,然后采用线性计权及Z计权方式对各楼层的振动特性进行分析,并分析了分别采用两种这计权方式时,特征频率下振动的传递特性,最后,利用有限元分析软件ABAQUS建立模型,进行了模态分析,找出了建筑物振动峰值出现在4楼的原因。结果表明,在线性计权及Z计权下,4个楼层的全局峰值均出现在50~63 Hz频率范围内;振动从1楼至4楼的传递过程中,中心频率为50 Hz和63 Hz频率段的振动加速度级均呈现先减小后增大的趋势,在2楼处达到最小,在4楼处达到最大;模态分析表明,在列车经过时,在频率为63 Hz时,4楼发生了共振现象,故其振动最为明显。

Analysis of vibration characteristics of multistory buildings under the influence of viaduct of urban rail transit

In order to explore the vibration characteristics of multi storied buildings along the urban rail transit, a 4 story building beside the urban rail transit viaduct of a city is taken as the research object, and vibration tests are performed on each floor simultaneously.Then the vibration characteristics of each floor are analyzed by using linear weighting and Z weighting method, and the two weighting modes are analyzed respectively for the transmission characteristics of vibration under characteristic frequency. Finally, the finite element analysis software ABAQUS is used to establish the model and modal analysis is carried out and the cause of building vibration peak appearing on the 4th floor is found out.The results show that under the linear weighting and Z weighting, the global peak values of the 4 floors all appear in the 50~63Hz frequency range; during the propagation of vibration from the 1st floor to the 4th floor, the vibration acceleration levels of the center frequency of 50Hz and 63Hz frequency decreases at first and then increases and it reaches the minimum at the 2nd floor and reaches the maximum at the 4 floor.Modal analysis shows that when the train passes and when the frequency is 63Hz, the 4th floor resonance occurs, so the vibration is the most obvious.