Abstract:In the underground space structure, the rationality of the external wall design will directly affect the engineering cost and structural safety. In building the overall model, it is usually assumed that the large underground space slab is infinite rigid in the plane. But for these situations, such as floor slab with side span opening, discontinuities slab, smaller stiffness ratio of wall and slab, the articulation still used at the connection of external wall and floor slab does not conform to the practical stress of slab wall. If the in-plane stiffness of floor slab is smaller than the bending resistance of the external wall in practical engineering, the mid span bending deformation of the external wall in the underground structure and the in-plane deformation of support plates are larger, which will lead to the internal force redistribution of the external wall. In case not considering, the larger calculation error will be caused. Therefore, when the plate wall is calculated and analyzed, the boundary condition of the external wall is actually a spring support with stiffness variation. In the design, the corresponding reinforcement measures should be taken according to the results of finite element calculation. Based on the underground space construction project in the north square of Rizhao Integrated Passenger Station, the finite element calculation is carried out for its external wall. The optimization design scheme of exterior wall structure for deep buried large space structure is put forward.
