Study on Stability of Secondary Reused Surrounding Rock of Self-Forming Roadway with Large Buried Depth and Roof Cutting

In order to study the stability of surrounding rock during the secondary reuse of deep-buried roof-cutting self-forming roadway, the deformation law and stress distribution characteristics of surrounding rock of track crossheading in advance 1615A working face section of Zhangbei Mine were analyzed by numerical simulation and field measurement. The results show that the roof is relatively stable during the reuse of retained roadway due to the dual effects of roof-cutting pressure relief and constant-resistance anchor cable reinforcement support, which is mainly manifested as floor heave and solid coal side heave, the surrounding rock is asymmetrically deformed, and the deformation rate shows a three-stage law along the advancing direction of the working face. There are four zoning characteristics of single abutment pressure in the roadway. The area within 15 m of the working face near the roadway side and within 40 m of the advance coal wall is significantly affected by the mining stress, showing an "L"-shaped distribution trend, and the peak value of the advance pressure is located at the "L"-shaped corner. During the reuse of retaining roadway, the bottom control, side control and separation monitoring should be strengthened. The research results can provide scientific basis for the control of roadway surrounding rock under similar engineering conditions.