ANALYSIS ON THREE DIMENSIONAL RESPONSE OF UTILITY TUNNEL UNDER INCONSISTENT SEISMIC EXCITATIONS

摘要

This paper concentrates on the response of utility tunnel under inconsistent excitation.The paper first simulates the multi-seismic excitation process by spectrum representation and then gets the displacement time history though integral twice of the artificial seismic acceleration time history.The three dimensional finite element model of utility tunnel was established,in which the artificial boundary condition,soil plasticity,the contact interface and so on are considered in the model.The calculated results revealed that the utility ttnnel show global bending deformation pattern under shear wave excitation.And the research showed that the strain amplitude of utility tunnel under the inconsistent seismic excitation was about 7 multiple larger than the consistent excitation,So the inconsistent excitation had significant influence on the seismic responses of utility tunnel.Therefore,special attention should be paid on this factor for seismic responses analysis.