Support Technology of Rectangular Roadway Based on Surrounding Rock Loose Circle Theory

To solve the tensile failure problem of rectangular roadway due to stress concentration, taking the roadway of 1509 working face in No. 5 mining area of Xinyi Coal Mine as the research object, based on surrounding rock loose circle theory, the scope of the loose circle of the roof of the roadway which are calculated by equivalent circle method and pressure arch method are respectively 1.21 m, 1.25 m, and the parameters of bolt and anchor are also designed. Then the combined support plan of “bolt + anchor + metal mesh” is determined in the roadway tunneling process. The numerical simulation results show that the displacement of the roof, floor and two sides of the roadway are respectively 30.65 mm, 29.01 mm, 25.08 mm, and the bolts were not broken. Numerical simulation and practice prove that the design scheme effectively controls the deformation of the surrounding rock of the roadway, and can keep the overall stability of the roadway.