Physical model test for the interaction on circular cross-section tunnel crossing ground fissure with 60°

Physical model test about the interaction between tunnel structure and soil under circler tunnel crossing the ground fissure belt with 60 degrees was carried out, measuring the longitudinal strains of structure, the relative displacement at the bottom of the tunnel and the surrounding rock pressure. The test results show the deformation on the tunnel structure with circular cross-section is a composition of bending, shearing and twisting. The main deformation in first stage of settlement is bending, but the twisting deformation is more outstanding after the void appears at the bottom of the tunnel. Structural deformation in hanging wall is larger than that of the footwall, whereas structural stress in footwall is larger than that of the hanging wall. The segmentation of lining tunnel structure should be utilized to fit the distortion, bending and shearing in the metro tunnel aslant crossing the ground fissure belt. Twisting action should be considered in the structural design, and the tunnel structure in footwall should be strengthened by using high-performance concrete.