Seismic Response Analysis of Immersed Tunnels Based on Different Joint Simulation Methods
Immersed tunnel is a longitudinal slender structure constructed by connecting the immersed segments with joints.The joint is the key part and weak link of the tunnel under the earthquake impact.In this paper,two joint simulation methods were proposed based on the common connection methods of immersed tunnel engineering:the uniform equivalent spring setting method along the cross section and the spring setting method based on the shear key effect of the cross section.The calculation is carried out based on the two joint simulation methods.The comparative analysis of the calculation results of the two simulation methods shows that both of them are in good agreement under longitudinal ground motion excitation,they are quite different under transverse ground motion excitation because the method of setting uniform equivalent spring setting along the cross section cannot reflect the shear characteristics of the joint.Moreover,the horizontal relative displacement of joints under transverse seismic is 2-3 times of that under longitudinal seismic.Therefore,more attention should be paid to the lateral seismic performance for immersed tunnels.The research results have a certain reference value for the establishment and application of reasonable simplified analysis model of immersed tunnels.
vibration and waveimmersed tunnelseismic responsesegment jointspring