关键词: 巷道支护, 衬砌结构, 近地表, 围岩控制

Abstract: Due to the poor mechanical properties of the surrounding rock of the roadway and the thinner section of the lining used in the initial support, the roadway under adverse geological conditions often deforms before the secondary support, which slows down the construction progress and affects the construction personnel. Personal safety. Based on the above problems, this paper simplified the initial support lining structure of the roadway under near surface conditions to a two-hinged arch. Using the principles of structural mechanics, the bending moment and axial force calculation formulas of the semicircular arch arch ring with the arch toe as the living hinge were derived. At the same time, with the air return shaft of No. 1 mine in Xinjiang Yili Coal Mine as the engineering background, Flac3D software is used to numerically simulate the initial support after the excavation of the roadway in Yili Coal Mine. The results show that the lining thickness and surrounding rock level have a great influence on the internal force distribution of the lining semicircular arch: when the lining thickness and surrounding rock strength level decrease, the bending moment and axial force at the semicircular arch foot will decrease simultaneously; semicircular arch bending The maximum value of the moment fluctuates most sharply when the thickness of the arch toe of the lining is 1-1.5 times the thickness of the vault, and it stabilizes after the thickness of the arch of the lining increases further. When the thickness of the lining is insufficient and the strength of the surrounding rock is low, the elastic resistance of the surrounding rock has a greater impact on the axial force of the semicircular arch arch foot. Research shows that the living hinge calculation method is more suitable for the internal force calculation under this mechanical environment.