The effect of vibration induced by metro traffic on sensitive instruments in a building near metro line 8 in Beijing was predicted by means of a dynamic finite element model combined with in-situ measurement of road traffic induced vibration, and vibration responses inside and outside the building for cases of general non-ballast track and floating slab track in tunnels were compared. Here, dividing meshes establishing boundary conditions and exerting damping in the finite element model were presented, the calculated dynamic wheel-rail force based on the in-situ vibration measurement on the rails are applied in the model. The results showed that the vibration induced by passage of metro trains in tunnels can be effectively predicted using the dynamic finite element model; the floating slab track is an effective vibration mitigation measure, it can efficiently reduce vibration in its work frequency range; however, the floating slab track cannot reduce vibration at lower frequencies, and has a certain action of amplifying vibration at its natural frequencies; the combined vibration due to road traffic and metro traffic affects a few sensitive instruments after starting the metro line 8, it can be reduced with passive isolation measures under the bases of equipments.%采用一种动力有限元数值模型,并结合道路交通现场振动测试,对北京地铁8号线列车运行对邻近地铁线路的某科研楼内精密仪器的振动影响进行了预测研究,并比较了普通无砟轨道和浮置板轨道两种工况下楼内外的振动响应.提出了该有限元模型的网格划分、边界条件、阻尼施加等建模原则,采用实测的钢轨振动加速度计算而来的动态轮轨力作为该模型上的激励力.结果表明:采用该动力有限元模型可以有效地预测地铁列车运行引起的振动；浮置板轨道是一种有效的减振措施,在其工作频段内有显著的减振效果,但对低频振动没有减振效果,而且在其自振频率处还有一定的放大作用；地铁8号线开通后,地铁列车振动再叠加上道路交通引起的振动会对科研楼内部分精密仪器的正常工作造成一定的影响,仪器基座处可采取相应的隔振措施来减小振动.
展开▼
