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Abstract Based on the beam-spring and shell-spring models for shield tunnels with double-layer lining，the compound and overlapping structures on a three-dimensional model were established respectively according to the different structure form of contact surfaces between the segment lining and the secondary lining. The plastic-damage model was adopted to represent the nonlinear characteristics of concrete. Considering the effect of rebar built in segment on the mechanical behaviors，the existing model was adopted to simulate the yielding，hardening and softening phenomenon of the reinforcement. In this model，the connecting bolts were simulated by the three-dimensional elements instead of spring elements. The discontinuity among the segments，connecting bolts and the secondary lining was faithfully reflected in this model. Two kinds of three-dimensional models were established for the Shiziyang tunnel on Guangzhou—Shenzhen—Hong Kong passenger dedicated railway. Three-dimensional models were verified by the results of similarity model test. The results show that the contact surfaces are separated and zero pressure zones appeared due to the local incompatible deformation between the segment lining and the secondary lining under the loading. The local stress concentration at the place of the key block in the secondary lining occurs easily. In this position，the axial force bending moment vary unevenly and the contact stress pressure is larger than that in other location.
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2016, Vol. 35 
