Abstract: To study the mechanical performance and deformation mode of new fabricated corrugated steel primary support composed of the corrugated steel plate and square steel pipe, the deformation, strain, and earth pressure of the structure are tested and analyzed through scale test. To investigate the stress distribution and bearing capacity of the structure under compression, a threedimensional finite element numerical simulation model is established. The effects of soil properties and structural geometric parameters on the stress state of lining structure are investigated by varying parameters, such as the thickness of the corrugated plate and the elastic modulus of soil. The findings are as follows: (1) The bearing performance of the square steel reinforced corrugated steel primary lining structure remains comparable to that of the traditional flexible pipe culvert. When the total vertical load is about 236.24 kN, 10.01 mm vertical shrinkage and 9.18 mm horizontal expansion occur. The maximum circumferential compressive stress produced by the corrugated plate is 24.24 MPa, and the stress level is low. (2) The structure′s ultimate bearing capacity under loading mode is approximately 1 411 kN. (3) During the loading process, square steel produces more internal force than corrugated steel plate, and has better load diversion and strengthening effect. (4) Soil properties have a great influence on the stress level of square steel, whereas corrugated plate thickness has little influence on the overall mechanical performance of the structure.

Key words: support with corrugated steel and square steel pipe; lining structure, scale test, numerical simulation