Raise boring method is one of the key technologies for coal mine shaft construction. The typical engineering of raise boring method is two types: large diameter shafts and small diameter gas pipeline shafts. Ensuring the stability of these two types of shaft structures is a key issue that determines the quality of raise boring engineering. In order to solve this problem, a method of evaluating the stability of shaft structure constructed by raise boring method is proposed in this paper. First, for large-diameter shafts, it is clear that the stability of surrounding rock is the key factor. Based on the strength reduction method, the stability coefficient of surrounding rock k_(0) =2.5 is proposed. Secondly, for the small diameter gas pipe shaft, it is clear that the stability of the gas pipe under the pressure of the filling material is the key factor. The functional equations of allowable compressive stress of the pipe material, the initial deviation of the gas pipes and the ultimate pressure are established, and a method with results biased towards safety is proposed for the design and verification of gas pipes.
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