输水隧道流-固耦合地震反应研究

目的为了研究在考虑介质的辐射阻尼的情况下，穿越软土地区的浅埋大管径输水隧道在内水作用下。其水体晃动、阻尼系数、地震激励方向、内水压力、围岩种类、围岩和衬砌的非线性以及衬砌的厚度对衬砌的地震响应的影响．方法根据流固耦合原理建立内水-衬砌-围岩三者的运动方程。以一穿越河底的输水隧道为例，采用三维流固耦合有限元程序对其进行地震反应分析．其中管内水体采用基于势的流体单元．结果经分析得出其中水体晃动、地震激励方向、高内水压力、围岩种类，围岩非线性及衬砌的厚度都对衬砌的地震响应的影响很大．结论采用有限元理论分析了对衬砌的地震响应有影响的几个因素，为工程设计与施工提供了可靠的理论依据．

Study on Seismic Response Concerning Fluid-Structure-Soil Coupling of Water-Supplying Tunnels

The paper has mainly studied the seismic response of the lining of shallow buried water-supplying tunnel in soft soil area under internal water pressure considering sloshing amplitude of the water,radiation damping of the medium,and has discussed the influence of coefficient of damping,direction of excitation,internal water pressure,kind of surrounding rock,nonlinear properties of surrounding rock and tunnel lining and thickness of tunnel lining.The paper sets the equation of motion among inner water-tunnel lining-surrounding rock based on the theory of fluid-structure interaction.With the FEM program of three-dimensional fluid-structure interaction,the seismic response of a water-supplying tunnel through the river bed is analyzed where potential-based liquid element is used for the inner water.According to the result of analysis,the seismic response of tunnel lining is strongly influenced by sloshing amplitude of the water,direction of excitation,high internal water pressure,kind of surrounding rock,nonlinear properties of surrounding rock and tunnel lining and thickness of tunnel lining.With the method of FEM,the paper has discussed the factors that have influence on the seismic response of tunnel lining,and it provides credible technical support for engineering design and construction.