地铁车站减振墙的动力特性分析

Dynamic Characteristics Analysis of Vibration DampingWall in Subway Station

为减少地铁列车运行产生的振动能量通过车站主体结构传播至地表,本文设计了一种车站减振墙。以雄安至北京大兴国际机场快线金融岛站为研究背景,通过在车站墙体内部设置由黏弹性材料构成的阻尼层形成减振墙,分析了列车荷载作用下减振墙的减振效果。研究结果表明:列车荷载作用下,从时程结果来看,车站减振墙最大可使车站周围土体平均振动加速度幅值减小28.6%,振动加速度峰值减小31.9%;从频谱分析来看,车站周围土体振动加速度峰值降幅最大为66.1%,平均降幅为45.1%;对应1/3倍频程谱,采用减振设计后,最大可使土体中振动加速度级降低5.5 dB,降幅达8.4%。通过在车站主体结构墙内部设置由黏弹性材料构成的阻尼层进行减振设计,可有效减少列车振动能量在车站主体结构内的传播。

In order to reduce the vibration energy generated by subway train operation transforming to the ground through the main structure of the subway station,a vibration isolation wall of the station is designed.Taking Jinrongdao station of the express line from Xiong'an to Beijing Daxing International Airport as the research background,a damping layer composed of viscoelastic materials is set inside the station wall to form a vibration isolation wall.The vibration reduction effect of vibration isolation wall under the train load is analyzed.The results show that:under the action of train load,in view from the time history results,the vibration isolation wall of the station can reduce the average vibration acceleration amplitude of the soil around the station by 28.6%and the peak vibration acceleration by 31.9%;in view from the spectrum analysis,the peak value of soil vibration acceleration around the station decreases by 66.1%at the maximum,with an average decrease of 45.1%;in view from 1/3 octave spectrum,the maximum vibration acceleration level in soil can be reduced by 5.5 dB,with a drop of 8.4%.It is concluded that setting the damping layer of viscoelastic materials into the main structure wall of the station can effectively reduce the propagation of train vibration energy in the main structure of the station.