基坑支护屏障对地铁列车引起的建筑振动隔离效果

Isolation Effect of Foundation Pit Support Barrier on Building Vibration Caused by Subway Train

基坑地下连续墙与回填材料构成一道隔振屏障。本文通过建立车辆-轨道-隧道-大地-建筑系统动力学模型,研究有无基坑支护屏障和采用不同回填材料时隔振屏障对地铁列车引起的建筑振动的隔离效果。结果表明:基坑支护屏障对不同楼层、不同频段振动的隔离效果不同,对地下楼层隔振效果较好,而对地上楼层隔振效果较差;回填材料类型会影响楼板振动主频和分频振级,进而影响对不同楼层的隔振效果。工程建设中应针对建筑结构和场地特征选取适宜的回填材料。

The underground continuous wall of the foundation pit and the backfill material form a vibration isolation barrier.By establishing a dynamic model of the vehicle-track-tunnel-earth-building system,the isolation effect of the foundation pit support barrier and the use of different backfill materials on building vibration caused by subway trains were studied in this article.The results show that,the isolation effect of the foundation pit support barrier is different for different floors and different frequency bands of vibration,with good isolation effect for underground floors and poor isolation effect for above ground floors.The type of backfill material will affect the main frequency and sub frequency vibration levels of floor vibration,thereby affecting the isolation effect on different floors.In engineering construction,suitable backfill materials should be selected based on the characteristics of the building structure and site.