THEORETIC ANALYSIS OF SIMPLIFIED CYLINDRICAL SHELL ON ELASTIC FOUNDATION FOR TUNNEL LONGITUDINAL SHEAR EFFECT
隧道纵向剪切效应的简化弹性地基柱壳理论解析

Based on the elastic plate theory, taking the influence of shear deformation into consideration, tunnel is regarded as the cylindrical shell on elastic foundation. By applying the theory of elastic cylindrical shell and simplified circular function, the overall stiffness of segment tunnel is separated as circumferential and radial shear stiffness and their effects on the deformation and internal forces are analyzed. The results show that it can improve the tunnel longitudinal structure behavior and reduce the bending moment of tunnel cross section by raising the stiffness of circumferential shear stiffness. It is suggested that a flexible ring with an appropriate stiffness should be applied in cross section design and a rigid design with certain flexibility in longitudinal section in soft ground. The conclusions are an important supplement for the theory of tunnel longitudinal shear transfer, which benefits to the optimization of the tunnel design.