Abstract: As the trend of underground space moves toward large space, it is often difficult to form effective support in a short period of time for the excavation and support of large underground space using traditional support. In order to solve the problems of too long primary support construction time and insufficient early morning strength, the corrugated steel support is introduced. Based on the fullscale corrugated steel structure joint model mechanical performance test, the structural strain, bolt axial force, structural deflection, and bending stiffness of the three joint types such as flat flange, back reinforced flange, and lap joint are studied. The results show that the initial flexural stiffness, initial bending moment of attenuation of bending stiffness, and decay rate of the three joint types of corrugated steel primary support are different. The initial flexural stiffness of the lap joint is the largest, the attenuation of the bending stiffness of the flat flange joint is the maximum, and the attenuation of flexural stiffness of the backreinforced flange joint is the minimum.

Key words: primary support, corrugated steel, joint, mechanical properties, experimental research