[关键词]
[摘要]
针对地铁小曲线半径地段环境振动对建筑物影响问题,本文运用车辆-轨道耦合动力学计算获得了振源激励,建立了列车动荷载作用下隧道-地层-建筑物有限元模型,结合现场测试验证了模型可靠性,研究了列车运行作用对浅基础、短桩基础、长桩基础以及筏形基础对建筑物振动响应规律的影响程度,研究结果表明:随着楼层的增加,建筑物的横向振动表现为先减少后增大,垂向振动表现为逐层增大的趋势;建筑物的振动在中高频成分(>20 Hz)有所增加,低频成分则有所衰减;垂向振动要大于横向振动,楼柱的振动要比楼板的振动更加明显;不同基础条件下建筑物垂向振级由大到小的排序分别为:筏形基础>浅基础>短桩基础>长桩基础,横向振级由大到小的排序分别为:浅基础>短桩基础>长桩基础>筏形基础,长桩基础对降低加速度振级最为有利。
[Key word]
[Abstract]
The dynamic model of vehicle-track coupling vibration in Small curve radius track is established. The calculated reaction force of the coupler is used as the excitation source, and the finite element model of tunnel-stratum-building under the action of metro is established. The reliability of the model is verified by measuring the vibration response data of tunnel wall in curved track during actual train operation. The basic form of building finite element model is changed and the influence degree of the vibration response of the building by adopting the four basic forms of the building that is short of shallow foundation, short pile foundation, long pile foundation and raft foundation is compared and analyzed. Research indicates: With floors increase, the building lateral vibration decreases firstly and then increases, while the vertical vibration increases floor by floor; The vibration of the building increases in the medium and high frequency components (> 20 Hz), while the low frequency components decrease; In general, vertical vibration is greater than lateral vibration and the column vibration is greater than the floor vibration; The descending order of vibration levels of the four working conditions is as follows: raft foundation> shallow foundation> short pile foundation> long pile foundation, while the order of lateral vibration order from large to small is as follows: shallow foundation> short pile foundation> long pile foundation> raft foundation; In general, long pile foundation is the most favorable for reducing acceleration vibration level.
[中图分类号]
U231.1
[基金项目]