SHELL-SPRING-CONTACT MODEL FOR SHIELD TUNNEL SEGMENTAL LINING ANALYSIS AND ITS APPLICATION

Considering the stress release around excavation, the shell-spring-contact calculation model of stratum-structure mode is presented so as to analyze the 3D member forces of the segmental linings of shield tunnel. With the application of FEM, the model employs several types of elements, such as thick shell, shear spring, rotational spring, compression spring, contact and solid elements, and concerns with the extrusion between segments in the joints, the stiffness contribution of joints, the cooperation between segments and surrounding rock, and the approximate insertion angle of Key Segment. Consequently, the complex mechanical behavior of the segmental linings can be effectively simulated by applying the model.