Study on floor heave mechanism and control technology of roadway based on slip line field theory

Based on the slip line field theory, the slip line field model of roadway floor is established.Taking 1021 roadway of Huipodi coal mine in Shanxi Province as the engineering background, the mechanism of asymmetric floor heave of roadway is studied, and the reasonable prevention and control technology of floor heave is put forward.The results show that: There are uniform stress field and non-uniform stress field in the stress field of roadway floor slip line.From the two sides to the center line of the roadway, the floor stress decreases gradually; The velocity of the active zone of the floor slip line is vertical downward.The transition zone rotates and compresses the passive zone due to the extrusion of the active zone.The passive zone moves upward, resulting in floor heave.Due to the stress concentration of isolated pillar in Huipodi coal mine, the abutment pressure on both sides of the roadway is asymmetric.The abutment pressure near the coal pillar forms a slip line field on the floor, and the direction of the velocity field points to the side of the roadway far away from the pillar.Therefore, the floor heave of 1021 roadway is asymmetric, and the floor heave height at the side far away from the pillar is larger.According to the characteristics of sliding floor heave in 1021 roadway, asymmetric support with parallel arrangement of single anchor cable is adopted to prevent floor heave of roadway, and the application effect is good.