Research on Utility Tunnel Seismic Response

Abstract:

The displacement time history input is recommanded for the seismic analysis of underground structures based on the deduction of the dynamic equation.A threedimensional finite element model of the utility tunnel with a consideration of many effects is established for the seismic analysis. The results reveal that the utility tunnel exhibits global bending deformation pattern under shear wave excitation. On the other hand, the effects of the boundary and the contact condition are significant to the structural strain. On the assumption that the structure is elastic,the strain amplitude of the free boundary condition is rather lower compared to the infinite element boundary condition, and the maximum relative error can reach 123.3%. When the slippage between the soil and structure is not considered, the structural strain amplitude can increase about 1/3.Finally,the paper presents a study of the influence of wave passage effect.