This paper tries to understand the mechanical characteristics of segment lining structure and tries to solve the difficulties in numerical analysis on segment lining structure. First, the joint mechanics model of segment ling is established, and the joint bending stiffness is then determined by simulating load test using largescale analysis software ANSYS. Secondly, mechanic analysis is carried out by beamspring analysis model using the combin7 element; The simulation results are compared with the calculation results of the conventional method and the modified conventional method, according to the different treatments of segment joint in mechanics. At last, the mechanical behavior of segments in longitudinal direction under the pushing force of the thrust cylinders is analyzed, the corresponding simplified threedimensional simulation method is then established, and comparative analysis is made on uniform pushing force and asymmetric pushing force. The research results can provide support for the design of lining segments of shield tunnels.