Study on floor instability law of cemented filling mining above a confined aquifer

Year 2023, , 85 - 92, 31.07.2023

Jiaqi Wang

https://doi.org/10.30797/madencilik.1077583

Abstract

To solve the problem of floor water inrush in the process of coal mining on a confined aquifer and study the law of floor instability, a cemented filling mining method is proposed in the paper. Using river sand and cement as filling materials, the cementitious material with a concentration of 75% and cement content of 15% has the best flow and mechanical properties. Based on the elastic half-space theory and the bearing characteristics of the backfill, the mechanical model of floor stability is established, the critical criterion of floor instability is proposed, and the relationship between the failure depth of floor and the location and pressure of confined aquifer is obtained. The numerical simulation test scheme is designed, and the FLAC3D fluid-structure coupling element is used to explore the instability characteristics of the floor in the mining process. The research results show that the failure depth of the floor will gradually decrease with the increase of the strength of filling materials, the increase of aquifer distance, and the decrease of water pressure. The research results provide a useful reference for the study of safe mining of coal resources on a confined aquifer.

Keywords

Confined aquifer, Cementitious materials, Filling mining, Floor, Numerical simulation test

References

• Batista-Rodriguez, J. A., Perez-Flores, M. A., Almaguer-Carmenates, Y., Blanco-Moreno, J. A., Lopez-Saucedo, F. D. J., & Batista-Cruz, R. Y. (2021). Using electrical resistivity tomography to evaluate the relationship between groundwater potential and tectonism in northeast Mexico. REVISTA MEXICANA DE CIENCIAS GEOLOGICAS, 38(1), 18-28.
• Du, Y., Liu, W., Meng, X., Pang, L., & Han, M. (2021). Effect of Crack Propagation on Mining-Induced Delayer Water Inrush Hazard of Hidden Fault. Geofluids, 2021.
• Duan, H., & Zhao, L. (2021). New evaluation and prediction method to determine the risk of water inrush from mining coal seam floor. Environmental Earth Sciences, 80(1), 1-13. Fu, B., & Wang, B. (2021). An Influence Study of Face Length Effect on Floor Stability under Water-Rock Coupling Action. Geofluids, 2021.
• Fahimifar, A., & Zareifard, M. R. (2009). A theoretical solution for analysis of tunnels below groundwater considering the hydraulic–mechanical coupling. Tunnelling and Underground Space Technology, 24(6), 634-646.
• Guo, J., Zhang, Q., Li, Q., & Chen, Z. (2021). Study on permeability evolution mechanism of aquifer coal seam roof sandstone under plastic flow. Geomechanics and Geophysics for Geo-Energy and Geo-Resources, 7(3), 1-22.
• Han, D., Currell, M. J., & Guo, H. (2021). Controls on distributions of sulphate, fluoride, and salinity in aquitard porewater from the North China Plain: Long-term implications for groundwater quality. Journal of Hydrology, 603, 126828.
• Jia, J., Hao, X., Zhao, G., Li, Y., Chuai, X., Huang, L., ... & Zhan, R. (2021). Evolution analysis of microseismic events before and after mining through large-scale weak zone with high confined water. Advances in Civil Engineering, 2021.
• Li, A., Mu, Q., Ma, L., Liu, C., Wang, S., Wang, F., & Mou, L. (2021). Numerical Analysis of the Water-blocking Performance of a Floor with a Composite Structure under Fluid–solid Coupling. Mine Water and the Environment, 40(2), 479-496.
• Liu, Z., Dong, S., Wang, H., Wang, X., Nan, S., & Liu, D. (2021). Macroscopic and mesoscopic development characteristics of the top strata of Middle Ordovician limestone in the Hanxing mining area. Environmental Earth Sciences, 80(16), 1-17.
• Ma, K., Sun, X. Y., Tang, C. A., Yuan, F. Z., Wang, S. J., & Chen, T. (2021). Floor water inrush analysis based on mechanical failure characters and microseismic monitoring. Tunnelling and Underground Space Technology, 108, 103698.
• Ma, D., H Duan, Liu, J., Li, X., & Zhou, Z. (2019). The role of gangue on the mitigation of mining-induced hazards and environmental pollution: an experimental investigation. Science of the Total Environment, 664(MAY 10), 436-448. doi: 10.1016/j.scitotenv.2019.02.059
• Ma, D., Duan, H., Li, X., Li, Z., Zhou, Z., & Li, T. (2019). Effects of seepage-induced erosion on nonlinear hydraulic properties of broken red sandstones. Tunnelling and Underground Space Technology, 91(SEP.), 102993. doi: 10.1016/j.tust.2019.102993
• Ma, D., Zhang, J., Duan, H., Huang, Y., & Zhou, N. (2021). Reutilization of gangue wastes in underground backfilling mining: overburden aquifer protection. Chemosphere, 264(Pt 1), 128400. doi: 10.1016/j.chemosphere.2020.128400
• Ning, S., Zhu, W., Yi, X., & Wang, L. (2021). Evolution Law of Floor Fracture Zone above a Confined Aquifer Using Backfill Replacement Mining Technology. Geofluids, 2021.
• Nam, S. W., & Bobet, A. (2006). Liner stresses in deep tunnels below the water table. Tunnelling and Underground Space Technology incorporating Trenchless Technology Research, 21(6), 626-635.
• Peng, Z., Chen, L., Hou, X., Ou, Q., Zhang, J., & Chen, Y. (2021). Risk Assessment of water inrush under an unconsolidated, confined aquifer: the application of GIS and information value model in the Qidong Coal Mine, China. Earth Science Informatics, 1-14.
• Sillitoe, R. H., & Brogi, A. (2021). GEOTHERMAL SYSTEMS IN THE NORTHERN APENNINES, ITALY: MODERN ANALOGUES OF CARLIN-STYLE GOLD DEPOSITS. Economic Geology, 116(7), 1491-1501.
• Shi, X., Zhou, H., Sun, X., Cao, Z., & Zhao, Q. (2021). Floor damage mechanism with cemented paste backfill mining method. Arabian Journal of Geosciences, 14(2), 1-9.
• Wang, Z., Li, W., & Hu, Y. (2021). Experimental study on mechanical behavior, permeability, and damage characteristics of Jurassic sandstone under varying stress paths. Bulletin of Engineering Geology and the Environment, 1-17.
• Wu, J., Jing, H., Meng, Q., Yin, Q., & Yu, L. (2021). Assessment of cemented waste rock backfill for recycling gangue and controlling strata: creep experiments and models. Environmental Science and Pollution Research, 1-17.
• Xu, C., Lu, C., & Wang, J. (2021). Interval uncertainty analysis of a confined aquifer. Scientific reports, 11(1), 1-5.
• Yin, H., Xu, B., Yin, S., Tian, W., Yao, H., & Meng, H. (2021). Prevention of Water Inrushes in Deep Coal Mining over the Ordovician Aquifer: A Case Study in the Wutongzhuang Coal Mine of China. Geofluids, 2021.
• Yan, H., Zhang, J., Li, B., & Zhu, C. (2021). Crack propagation patterns and factors controlling complex crack network formation in coal bodies during tri-axial supercritical carbon dioxide fracturing. Fuel, 286, 119381. doi: 10.1016/j.fuel.2020.119381
• Yin, H., Zhao, C., Zhai, Y., Sang, S., Zhao, H., Li, S., ... & Zhuang, X. (2020). Application of comprehensive support techniques to roadway tunneling in vicinity of Ordovician carbonate confined aquifers under complicated tectonic conditions. Carbonates and Evaporites, 35(4), 1-14.
• Zhang, J., Guo, L., Mu, W., Liu, S., & Zhao, D. (2021). Water-inrush Risk through Fault Zones with Multiple Karst Aquifers Underlying the Coal Floor: A Case Study in the Liuzhuang Coal Mine, Southern China. Mine Water and the Environment, 1-11.
• Zhang, Y. (2021). Mechanism of Water Inrush of a Deep Mining Floor Based on Coupled Mining Pressure and Confined Pressure. Mine Water and the Environment, 40(2), 366-377.
• Zhang, Q. L., & Wang, X. M. (2007). Performance of cemented coal gangue backfill. Journal of Central South University of Technology, 14(2), 216-219. doi: 10.1007/s11771-007-0043-y
• Zhang, J., Qiang, Z., Sun, Q., Gao, R., Germain, D., & Abro, S. (2015). Surface subsidence control theory and application to backfill coal mining technology. Environmental Earth Sciences, 74(2), 1439-1448. doi: 10.1007/s12665-015-4133-0
• Zhou N, Han X, Zhang J, et al. (2016). Compressive deformation and energy dissipation of crushed coal gangue[J]. Powder Technology, 297:220–228. doi: 10.1016/j.powtec.2016.04.026
• Zhang, J., Qiang, Z., Sun, Q., Gao, R., Germain, D., & Abro, S. (2015). Surface subsidence control theory and application to backfill coal mining technology. Environmental Earth Sciences, 74(2), 1439-1448. doi: 10.1007/s12665-015-4133-0