Based on the engineering geological conditions of a coal mine in western China, this research focuses on addressing the challenges associated with rock burst prevention in working face of inclined thick coal seams. Theoretical analysis, mechanical modeling, numerical simulation, and field monitoring were employed to analyze the influencing factors and hazardous areas of rock burst in working face of an inclined thick coal seam. Optimization strategies for double entry inward layout were proposed and subsequently validated through engineering application. It is found that the occurrence of rock burst is influenced by several factors including buried depth, thick-hard roof, coal seam dip angle, coal pillars, bottom coal. The belt and track roadways were identified as zones with strong rock burst danger, while the setup entry was categorized as a zone with moderate rock burst danger. Based on an analysis of roof structure evolution and floor stress calculations, the floor was divided into three low-stress zones: the semi-protected zone beneath key blocks (I), the protected zone beneath key blocks (Ⅱ), and the stress release zone of gangue (Ⅲ). Numerical simulations determined that the optimal positioning was within the protected zone beneath key blocks (Ⅱ), specifically at a horizontal distance of 5.15 m from the right of the track roadway and a vertical distance of 3 m from the goaf. Microseismic and pressure monitoring demonstrated that implementing the double entry inward layout transformed the energy release pattern of the surrounding rock from "low-frequency and high-energy" to "high-frequency and low-energy". Furthermore, the duration of continuous pressure was significantly reduced, thereby mitigating the rock burst danger in the working face.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |