Mechanism and Control of Roadway Floor Heave in the Paleogene Soft Rock Surroundings

To analyze the mechanism of roadway floor heave in the Paleogene soft rocks and provide corresponding control strategies, taking the monorail lane of the Liuhai Mine as the research background, the special geological conditions of the deep soft rock roadway and failure characteristics of the roadway floor are analyzed by means of an indoor physical experiment and numerical simulation. Through research on the mechanism of the floor heave of the roadway, the main influencing factors of the floor heave are determined. It was found that the high stress jointed strong swelling composite soft rock is the main cause, and the lack of supporting theory and backwardness of support design methods are the direct reasons for the floor heave of the roadway. On this basis, a new coupling support technology of a bolt-mesh-anchor-base angle bolt-flexible layer truss for controlling roadway floor heave has been proposed and applied in the field. The numerical analysis and field monitoring results show that the roadway floor heave control technology can improve the stress state of the surrounding rock of the floor, cut off the shearing and sliding deformation of the bottom corner, effectively control the roadway floor heave deformation, and ensure the overall stability of the roadway. It provides a reference for the mechanism and control of roadway floor heave under similar conditions.