In order to study the failure mechanism and acoustic emission characteristics of coal–rock combination with different coal-to-rock ratios, carry out uniaxial compression test and acoustic emission test on coal–rock combination with three coal–rock ratios of 1:2, 1:1, 2:1, start with parameters such as failure characteristics, stress-time curve, compressive strength, elastic modulus, acoustic emission events and energy counts, and analyze the failure characteristics, deformation characteristics and acoustic emission characteristics of the combined body. The result shows the following. The destruction of the coal–rock assembly occurs in the coal body, with the increase of the coal-to-rock ratio, the damage degree of the specimen gradually decreases, the broken shape gradually changes from broken and collapsed, and after tensile splitting, it becomes oblique shear failure. There is a phenomenon of "stress jump" and residual stress in coal-rock combination, after the stress reaches the peak, it jumps to the maximum value of residual stress, the larger the coal–rock ratio, the smaller the peak stress, but the residual stress is almost unchanged. The compressive strength and elastic modulus of the composite body decrease with the increase of coal-rock ratio, and the maximum axial strain increases with the increase of coal–rock ratio. Acoustic emission events and energy counts both showed stage changes that matched the stress–time curve. The energy counts and event counts at the same stage decreased as the coal–rock ratio increased.

In order to overcome the support difficulty of serious floor heave caused by rock burst, with the floor heave of ventilation roadway in Hegang Xing An Coal Mine as the engineering background, the treatment scheme of the concrete‐filled steel tube corner pile and floor grouting is put forward. Based on the solution of the slip line field under plane strain condition, the mechanical model of the slip‐type floor heave is established, and the formula for calculating the critical failure depth of the roadway floor and the minimum support depth of the corner pile is derived. Through numerical analysis and similar model tests, the deformation and stress distribution of surrounding rock under the support of the corner piles are studied, and the force law of the pile under high horizontal stress is analyzed. The results show that, compared with the floor corner anchor, the floor corner pile + floor grouting support scheme can significantly improve the mechanical properties of the floor rock mass, and the plastic slip line of the floor plate part can be cut by corner piles, which effectively controls the deformation of the floor plate under high horizontal stress; the length and inclination angle of the corner pile have a great influence on the support effect. In the on‐site treatment scheme, 1.1 times the calculated length of pile should be selected. The results of a similar model and field test show that the corner pile is effective in controlling the deformation of roadway floor and two sides.

According to the characteristics of rock burst of high horizontal stress roadway floor, the rock burst mechanism of roadway floor was studied with the background of south track roadway Xing’an mine. Based on the deflection theory and energy principle of the slab, the mechanical model of the floor of the roadway under high horizontal stress was established, the stress and energy criteria of rock burst occurred in the floor of the roadway were deduced, the prevention and control measures of the floor pressure relief with large diameter borehole and concrete‐filled steel tube pile support were put forward, and the key parameters were determined. By establishing a numerical model, the evolution law of plastic zone, horizontal stress, and elastic strain energy density of roadway floor with or without support is contrastively analyzed. The results show that the effective means to prevent and control the floor rock burst is to cut off the stress transfer path by weakening the hard floor to reduce floor energy accumulation so as to reduce the floor rock burst risk. Based on the above research, field tests were carried out, and the microseismic monitoring results showed that the floor pressure relief of large diameter boreholes and concrete‐filled steel tube pile support effectively relieved the floor rock burst and guaranteed the safety and efficiency of roadway excavation. This technology can provide a reference for the prevention and control of floor rock burst of similar roadways.