Mechanism for Controlling Floor Heave of Mining Roadways Using Reinforcing Roof and Sidewalls in Underground Coal Mine

Controlling floor heave plays an important role in the stability of mining roadways that is pivotal to the sustainable, safe, and efficient development of coal resources in underground coal mines. In order to propose highly efficient and economical methods of controlling floor heave, numerical simulation, laboratory physical simulation, and engineering practice were carried out to reveal the mechanism of reinforcing roof and sidewalls to control the floor heave of the mining roadway, return airway 15208, in the Xinjing Coal Mine in the Yanquan mining area of China. The numerical simulation demonstrated that the surrounding rock of the roadway underwent expansion and deformation, accompanied by redistribution of the surrounding rock stress due to the reinforcement of the roof and two sidewalls. The laboratory physical simulation revealed that the reinforcing roof and sidewalls decreased the bed separation of the floor and reduced the quantity of the displacement of the floor in Coal Seam 15. Engineering practice showed that the floor heave in the roadway, the roof, and the sidewalls, which was reinforced by intensive bolts combined with steel belt, wire mesh, and cable, was significantly reduced compared with that with lower supporting intensity of roof and sidewalls. The floor heave could be successfully controlled.