Influence of diaphragm wall on seismic response of underground structures in weak interlayer site
In the seismic analysis of underground structures,the issues of underground structures in the weak interlayer sites are more prominent than in the generally layered sites.The research object is a double-story and double-span rectangular frame subway station structure.Based on the finite element software ABAQUS,a static and dynamic coupled finite element analysis model of soil-diaphragm wall-structure system is established to study the influence of diaphragm wall on the seismic response of underground structure in weak interlayer sites.The effects of the diaphragm wall and connection method of diaphragm wall on the seismic responses of the underground subway station are investigated and analyzed.As a result,the synergistic effect of diaphragm wall and station structure makes the overall horizontal deformation of the station structure reduced,and the reduction effect is more obvious with the increase of the thickness of the weak interlayer.The diaphragm wall will cause additional lateral earth pressures to act on the station structure,which adversely affects the upper middle column and the top of the side wall,and it is recommended that certain strengthening measures be taken in engineering practice.