Influence about the stiffness ratio of the double-shell lining to the dynamic response of tunnel structure under earthquake

Abstract: This paper mainly focused on analyzing the influence of relative stiffness ratio to the dynamic response of tunnel structure. The relative stiffness ratio is the one between primary support and secondary lining. The numerical model of a two-line highway tunnel with variable stiffness ratio is obtained by applying ABAQUS. By analyzing the relative displacement, the maximum principle stress and the minimum principle stress, the following conclusion is reached: 1, enlarging the stiffness ratio will minimize the relative displacement, which consequently reduces the interaction between the primary support and secondary lining. 2, the skewbacks are the critical parts in seismic design of tunnel. Both tensile and compressive failures are possible to appear at this position. 3, an optimum stiffness ratio should exist to reach the smallest relative displacement and a structure with no tension or compression failures. Further study including indoor model tests should be performed.