Study on the Overburden Failure Law of Extra-Thick Coal Seam Mining Under Extremely Thick Conglomerate Strata
Source abstract
Abstract
This study investigates the mining-induced overburden failure and the development law of the water-conducting fracture zone under key layer control during the extraction of an extra-thick coal seam (thickness ≥ 8 m) under extremely thick conglomerate strata (thickness ≥ 200 m) in the Zhaoxian Coal Mine, Binchang mining area, Shaanxi Province, China. A combined approach utilizing FLAC3D numerical simulation and ground borehole full-section resistivity monitoring was adopted. The results indicate that the primary key layer (extremely thick conglomerate) and the sub-key layer (sandy mudstone) exert a significant inhibitory and segmented control effect on fracture development. The height of the water-conducting fracture zone increases in a “step-like” pattern with working face advancement, stabilizing at 270.3 m; the Rh/m is 23.5. The overburden failure morphology evolves dynamically through stages described as “funnel shape–concave shape–inverted trapezoid shape” as mining progresses. Field resistivity monitoring results (fracture zone height of 255 m, Rh/m of 22.17) show good agreement with numerical simulations, validating the control mechanism of key layers on overburden failure. These findings provide a theoretical basis for safe mining practices and water resource protection in extra-thick coal seams overlain by extremely thick conglomerate strata.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Rock Mechanics and Modeling · Tailings Management and Properties · Geoscience and Mining Technology
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
The Key Laboratory of Mine Geological Disaster Prevention of Anhui Province, Anhui University of Science and Technology, Huainan 232001, China
State Key Laboratory for Safe Mining of Deep Coal Resources and Environment Protection, Huainan 232000, China
School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, China
Anhui Huizhou Geology Security Institute Co., Ltd., Hefei 231202, China
Funding
Research Start-up Fund for High-level Introduced Talents of Anhui University of Science and Technology · Open Foundation of the Key Laboratory of Mine Geological Disaster Prevention of Anhui Province · Open Fund of State Key Laboratory for Safe Mining of Deep Coal Resources and Environment Protection
References (23)
Show source-provided references
1. Influence of thick sandstone on development of overburden mining fissures in northern Shaanxi coal mining area of Yellow River Basin and suggestions on water-preserved coal mining
2. The law of overburden failure and water conservation mining method of extra thick coal seams covered by extremely thick soil layers
3. Developmental pattern of water flowing fractured zones in the soil-bedrocktype overburden and water-controlled mining strategy under a super-large mining height
4. Regional distribution law of water–conducting fractured zone height in high–strength mining of thick and extra–thick coal seams in China
5. Critical failure of overlying rock strata and its criteria induced by high–intensity longwall mining
6. Development status and prospect of green mining and ecological restoration technology of coal mines in China
7. Research advances in mining fractures evolution law of rock strata and ecological treatment technology
8. Research progress of mining overlying stratas failure law and control technology
9. Investigation of surrounding rock stability during proximal coal seams mining process and feasibility of ground control technology10.1016/j.psep.2024.04.091 ↗
10. Evaluation and analysis of metal mine filling based on numerical simulation and actual measurement10.1007/s12665-021-09844-8 ↗
11. Experiment and numerical simulation of overburden and surface damage law in shallow coal seam mining under the gully10.1007/s10064-022-02706-y ↗
12. Xu, Z., Xu, W., Zhu, Z., and Zhao, J. (2023). Research on monitoring and stability evaluation of ground subsidence in gypsum mine goaf. Front. Environ. Sci., 10.10.3389/fenvs.2022.1097874 ↗
13. Xu, Z., Xu, W., Zhou, P., Zhu, Z., Zhao, J., and Gao, P. (2023). Research on Coal Mine Goaf Restoration Based on Stability of Overlying Rocks and Numerical Simulation Analysis: A Case Study of Jingmen Garden Expo Park. Sustainability, 15.10.3390/su15021464 ↗
14. Overburden structure fracture evolution and ground pressure behavior under oblique residual coal pillars in thick seam mining10.1038/s41598-025-16295-9 ↗
15. Longwall mining-induced weighting mechanism and its interactions with shield support and coal wall
16. Li, J., Li, B., He, K., Gao, Y., Wan, J., Wu, W., and Zhang, H. (2022). Failure mechanism analysis of mining-induced landslide based on geophysical investigation and numerical modelling using distinct element method. Remote Sens., 14.10.3390/rs14236071 ↗
17. Wang, Y., Wu, G., Liu, Y., and Cheng, Z. (2022). Study on overlying strata movement and surface subsidence of coal workfaces with karst aquifer water. Mathematics, 10.10.3390/math10020169 ↗
18. Xu, J., Pan, J., Li, M., Wang, H., and Chen, J. (2025). Dynamic evolution of fractures in overlying rocks caused by coal mining based on discrete element method. Processes, 13.10.3390/pr13030806 ↗
19. Numerical modeling analysis of floor stress distribution under coal pillars and roadway stability in close-distance coal seams
20. Evolutionary pattern and control technology of mine pressure when mining face for coal pillars in main roadways passing through abandoned roadways
21. Yang, J., Chen, Y., Li, P., Xu, C., and Zhang, M. (2025). Localized swelling-induced instability of tunnel-surrounding rock: Experimental and FLAC3D simulation study. Appl. Sci., 15.10.3390/app152011101 ↗
22. Resistivity anisotropy analysis of Longmaxi shale by resistivity measurements, scanning electron microscope, and resistivity simulation10.1016/j.jappgeo.2022.104700 ↗
23. Li, C., Wei, L., Xu, Q., Yang, L., Li, J., and Wan, X. (2024). Structural detection and stability monitoring of deep strata on a slope using high-density resistivity method and FBG strain sensors. Appl. Sci., 14.10.3390/app14083272 ↗