Abstract:

Dislocation would easily occurs to soil and underground structure under strong earthquake, which has great influence on aseismatic performance of underground structure. Hence, the influences of soilstructure interface on transverse seismic response characteristics of lining structure under different surrounding rocks and buried depths are studied by finite element method to guarantee the longterm safety of the tunnel operation. The study results show that: (1) With the improvement of soil condition, the extreme value of axial force of tunnel lining structure increases significantly, while the extreme values of shear force and bending moment of tunnel lining structure decrease significantly, and the variation amplitude of dynamic internal force of tunnel lining structure induced by dislocation of soilstructure interface decreases significantly; with the increase of buried depth, the variation amplitude of dynamic internal force of tunnel lining structure induced by dislocation of soilstructure interface decreases significantly. (2) When considering the dislocation of soilstructure interface, the better the tunnel surrounding rock conditions and the larger the buried depth are, the smaller the horizontal slip of tunnel lining is. (3) When tunnel surrounding rock condition is poor or the buried depth is small, the influence of soilstructure interface on the aseismatic performance of tunnel should be fully considered in aseismatic design of tunnel lining structure.

Key words: shield tunnel, lining structure, soilstructure interface, surrounding rock condition, buried depth, seismic response