Based on the engineering problem of large deformation and support failure in the roadway of Ronghua No. 1 Mine, on-site in situ stress testing was carried out to understand the distribution characteristics of the in situ stress around the roadway. Then, a stability analysis of the roadway was conducted on the key factors causing support failure. Combining the on-site situation and the results of the stability analysis, the principle of surrounding rock stability control in a high horizontal stress roadway was proposed. Based on this principle, an optimized scheme was designed. The optimized scheme and the original scheme were comparatively analyzed through numerical simulation to verify the applicability of the optimized scheme. Finally, the optimized scheme was applied on-site, and the roadway was monitored. The results were as follows: (1) from the results of the in situ stress test conducted in Ronghua No. 1 mine, the horizontal tectonic stress field is dominant. (2) Based on the characteristics of in situ stress distribution, the angle between the direction of the maximum horizontal principal stress and the roadway orientation, along with varying lateral pressure coefficients, is directly proportional to the stress and deformation of the surrounding rock. (3) Through numerical simulation analysis, an optimized support scheme was proposed based on the original design. The roof subsidence was reduced by 37.3%, the floor heave was reduced by 49.5%, and the side convergence was reduced by 34.7%. The surrounding rock stability of the roadway was significantly improved. (4) The optimized support scheme was applied in the 6A# Left Second roadway at Ronghua No. 1 Mine. Through on-site monitoring of the perimeter rock deformation, significant reductions in deformation and increased stability were observed. The research content provides a theoretical basis and practical experience for the stabilization of high horizontal stress roadways.

The coal and gas outburst and rockburst coupling disaster is becoming increasingly serious due to deep mining. To clarify the mechanism inducing the outburst–rockburst coupling disaster, a true triaxial single-sided unloading mechanical test was conducted with the aid of a true triaxial solid–thermal–gas coupling test device, an industrial computed tomography (CT) system, and an acoustic emission system. Through this test, the mechanical characteristics, meso crushing characteristics, and acoustic characteristics in the disaster formation process were obtained. Additionally, the outburst–rockburst coupling instability disaster law was verified by numerical simulation. The results demonstrated that the stress unloading degree of the coal body was negatively correlated with the initial gas pressure in the outburst–rockburst coupling disaster. The time domain parameter count and energy of acoustic emission exhibited a “bimodal” distribution pattern in the instability stage. The rockburst would occur when the peak value was in a “low-count and high-energy” state, while coal and gas outburst would occur when the peak value was in a “high-count and low-energy” state. The meso slice revealed that gas degradation promoted the development of microcracks in the coal body, and the penetration of cracks resulted in the main cracks of structural instability during rockburst. The coal and gas outburst was mainly attributed to the “cross” shear failure pattern of the coal body. These research findings may lay a foundation for the effective prevention and control of outburst–rockburst coupling disasters.

To research the percolation rate of gas‐filled coal based on true triaxial condition, this paper uses the three‐phase coupling true triaxial servo test device to carry out the seepage test of coal, and the percolation rate of coal under different conditions of three factors such as gas pressure was measured by Darcy’s law, and the variation of percolation rate of coal was studied based on the comprehensive consideration of thermal elastic swelling deformation, expansion deformation of adsorbed gas, and compression deformation of interstitial pressure. The results are as follows: (1) When the main stress and temperature maintain unchanged, the percolation rate presents the trend which first decreases and then becomes gentle with the gas pressure; when the gas pressure and main stress maintain unchanged, the percolation rate increases with the decrease of temperature; when the pressure and temperature maintain unchanged, the changes of percolation rate present a shape of “V” with the main stress. (2) The strain curve of gas‐filled coal decreases at first and then increases; that is, the percolation rate decreases gradually when the strain increases at the compression phase and elastic phase, while the percolation rate increases with the increase of strain at the yield phase and failure phase. (3) In the process of increasing volume stress, the percolation rate decreases gradually in the pore compaction stage, the percolation rate increases gradually from crack propagation to peak failure stage, and then, the percolation rate increases significantly after the peak damage. According to the test results, the percolation rate and volume strain show an inverse proportion.

With the increase of mining height at the working face, the influence range of roof fractures in the goaf increases, the advanced supporting pressure on the coal wall increases, ground pressure becomes more intense, and roof support becomes more difficult. Based on the analysis of ground pressure behavior in the first mining and caving stage, the normal mining stage, and the final mining breakthrough stage of the fully-mechanized mining face near 12,404, the relationship between conveyor current and coal speed is studied and compared. Based on the intelligent control system of the fully-mechanized mining face with a super-high mining height of 12,404 and the structure of the football team, the “playing football” roof control mode of the fully-mechanized mining face with super-high mining height under the background of 5G+ big data is put forward. The conclusions are as follows: In 12,404, the ground pressure was first mined. During normal mining, when the roof with a buried depth of more than 200 m is broken, the speed of the coal machine is kept within 12 m/min, and the full guard defends and controls the roof, pulling the lead frame through the area with severe ground pressure. When the roof is good, it is necessary to speed up the coal cutting and get rid of the pressure. When it is less than 200 m, it will overcome the local weighting, and show an offensive trend to speed up and increase production. In the final mining breakthrough stage, the speed of the coal machine should be controlled within 8 m/min, with attention to defense, guarding against roof leakage, and reducing waste rock.