Abstract
The study focuses on the stability control measures for mining roadways in fault zones of deep mines, using Daqiang Coal Mine as a case study. The control system under consideration, referred to as “pre-splitting cutting roof + NPR anchor cable” (PSCR-NPR), is subjected to scrutiny through theoretical analysis, numerical modelling, and field trials. Furthermore, a comprehensive analysis is undertaken to evaluate the stability control mechanism of this particular technology. The study provides evidence that the utilization of deep-hole directional energy-concentrated blasting facilitates the attainment of directional roof cutting in roadways. The aforementioned procedure leads to the formation of a uniform structural surface on the roof of the roadway and causes modifications in the surrounding geological formation. The examination of the lateral abutment pressure and shear stress distribution, both prior to and subsequent to roof cutting, indicates that the implementation of pre-splitting techniques leads to a noteworthy reduction in pressure. The proposition of incorporating the safety factor Q for roof cutting height is suggested as a method to augment comprehension of the pressure relief phenomenon in the field of engineering. The analysis of numerical simulation has indicated that the optimal pressure relief effect of a mining roadway in a fault area is attained when the value of Q is 1.8. The NPR anchor cable exhibits noteworthy characteristics, including a high level of prestress, continuous resistance, and substantial deformation. After the excavation of the roadway, a notable reduction in radial stress occurs, leading to the reinstatement of the three-phase stress state in the surrounding rock. This restoration is attributed to the substantial prestress exerted on the radial stress. The termination point of the NPR anchor cable is strategically positioned within a stable rock formation, allowing for the utilization of the mechanical characteristics of the deep stable rock mass. This positioning serves to improve the load-bearing capacity of the surrounding rock. The mining roadway within the fault region of Daqiang Coal Mine is outfitted with the PSCR-NPR technology. The drop in shear stress experienced by the rock surrounding the roadway is estimated to be around 30%, whilst the low-stress region of the mining roadway extends by a factor of approximately 5.5. The magnitude of surface displacement convergence experiences a decrease of approximately 45%–50%. The study’s findings provide useful insights regarding the stable of mining roadway in characterized by fault zones.
Data availability: Data supporting this research article are available from the corresponding author on request.
References
Bai J, Dou L, Li J, et al. (2022) Mechanism of Coal Burst Triggered by Mining-Induced Fault Slip Under High-Stress Conditions: A Case Study. Front Earth Sci 10:884974. https://doi.org/10.3389/feart.2022.884974
Cai W, Dou L, Si G, et al. (2021) Fault-induced coal burst mechanism under mining-induced static and dynamic stresses. Eng 7(5): 687–700. https://doi.org/10.1016/j.eng.2020.03.017
Cai W, Dou L, Wang G, et al. (2019) Mechanism of fault reactivation and its induced coal burst caused by coal mining activities. J Min Saf Eng 36(6): 1193–1202. (In Chinese) https://doi.org/10.13545/j.cnki.jmse.2019.06.016
Chen S, Zhao B, Yuan Y, et al. (2021) Engineering experiment on gob-side entry retaining by roof cutting of deep mining face in Chengjiao coal mine. J Mi Saf Eng 38(1): 121–129. (In Chinese) https://doi.org/10.13545/j.cnki.jmse.2020.0067
Cheng Y, Wang J, Xie G, et al (2010) Three-dimensional analysis of coal barrier pillars in tailgate area adjacent to the fully mechanized top caving mining face. Int J Rock Mech Min Sci 47(8): 1372–1383. https://doi.org/10.1016/j.ijrmms.2010.08.008
Dai L, Pan Y, Li Z, et al. (2021) Quantitative mechanism of roadway rockburst in deep extra-thick coal seams: Theory and case histories. Tunn Undergr Space Technol 111: 103861. https://doi.org/10.1016/j.tust.2021.103861
Dai L, Pan Y, Wang A, et al. (2020) Experimental study on the self-protection performance of anchor bolts with energy-absorbing tails. Rock Mech Rock Eng 53: 2249–2263. https://doi.org/10.1007/s00603-019-01990-7
Dai L, Pan Y, Zhan C, et al. (2022) New criterion of critical mining stress index for risk evaluation of roadway rockburst. Rock Mech Rock Eng 55: 4783–4799. https://doi.org/10.1007/s00603-022-02888-7
Dou L, Zhou K, Song S, et al. (2021) Occurrence mechanism, monitoring and prevention technology of rock burst in coal mines. J Eng Geol 29(4): 917–932. (In Chinese)
Gao Y, Wang J, Gao H, et al. (2019) Mine pressure distribution and surrounding rock control of gob-side entry formed by roof cutting and pressure release under the influence of faults. Chin J Rock Mech Eng 38: 2182–2193. (In Chinese) https://doi.org/10.13722/j.cnki.jrme.2019.0617
He M (2021) Research progress of deep shaft construction mechanics. J Chin Coal Soc 46(3): 21. (In Chinese) https://doi.org/10.13225/j.cnki.jccs.YT21.0124
He M, Gao Y, Gai Q, et al. (2023) Mechanical principle and mining methods of automagical entry formation without coal pillars. Coal Sci Technol 51(1): 19–30. (In Chinese) https://doi.org/10.13199/j.cnki.cst.2022-1850
He M, Ren S, Guo L, et al. (2022) Experimental study on influence of host rock strength on shear performance of Micro-NPR steel bolted rock joints. Int J Rock Mech Min Sci 159–105236. https://doi.org/10.1016/j.ijrmms.2022.105236
He M, Wang Q, Wu Q (2021) Innovation and future of mining rock mechanics. J Rock Mech Geotech. https://doi.org/10.1016/j.jrmge.2020.11.005
Jiang Y, Wang H, Xue S, et al. (2012) Assessment and mitigation of coal bump risk during extraction of an island longwall panel. Int J Coal Geol. https://doi.org/10.1016/j.coal.2012.02.003
Kan J, Dou L, Li X, et al. (2022) Investigating the destressing mechanism of roof deep-hole blasting for mitigating rock bursts in underground coal mines. Geomat Nat Haz Risk 13: 2508–2534. https://doi.org/10.1080/19475705.2022.2122594
Li L, Wu J, Pan Y, et al. (2020) Influencing factor analysis on the anomalously low-friction effect in the block rock mass. Adv Civ Eng 1–12. https://doi.org/10.1155/2020/8831486
Li Z, Dou L, Cai W, et al. (2016) Mechanical analysis of static stress within fault-pillars based on a voussoir beam structure. Rock Mech Rock Eng 49: 1097–1105. https://doi.org/10.1007/s00603-015-0754-6
Lu A, Dou L, Bai J, et al. (2021) Mechanism of hard-roof rock burst control by the deep-hole blasting: Numerical study based on particle flow. Shock Vib 1–14. https://doi.org/10.1155/2021/9527956
Pan Y, Qi Q, Wang A, et al. (2020) Theory and technology of three levels support in bump-prone roadway. J Chin Coal Soc 45(5): 1585–1594. (In Chinese) https://doi.org/10.13225/j.cnki.jccs.DY20.0261
Shan R, Li Z, Wang C, et al. (2021) Research on the mechanism of asymmetric deformation and stability control of near-fault roadway under the influence of mining. Eng Fail Anal 127: 105492. https://doi.org/10.1016/j.engfailanal.2021.105492
Sun X, Li G, Zhao C, et al. (2019) Investigation of deep mine shaft stability in alternating hard and soft rock strata using three-dimensional numerical modeling. Processes 7: 2. https://doi.org/10.3390/pr7010002
Sun X, Zhang B, Li G, et al. (2019) Application of constant resistance and large deformation anchor cable in soft rock highway tunnel. Adv Ci Eng. https://doi.org/10.1155/2019/4347302
Sun X, Zhao C, Tao Z, et al. (2021) Failure mechanism and control technology of large deformation for Muzhailing Tunnel in stratified rock masses. Bull Eng Geol Environ 80: 4731–4750. https://doi.org/10.1007/s10064-021-02222-5
Tao Z, Luo S, Qiao Y, et al. (2021) Key factors analysis and constitutive equation modification of a macro-NPR bolt for achieving high constant resistance and large deformation characteristics. Int J Rock Mech Min Sci 147: 104911. https://doi.org/10.1016/j.ijrmms.2021.104911
Tao Z, Xu H, Zhu C, et al. (2020) The study of the supernormal mechanical properties of giant NPR anchor cables. Shock Vib 1–13. https://doi.org/10.1155/2020/2621909
Wang H, Jiang Y, Zhao Y, et al. (2013) Numerical investigation of the dynamic mechanical state of a coal pillar during longwall mining panel extraction. Rock Mech Rock Eng 46(5):1211–1221. https://doi.org/10.1007/s00603-012-0337-8
Wang Q, Xu S, Xin Z, et al. (2022) Mechanical properties and field application of constant resistance energy-absorbing anchor cable. Tunn Undergr Space Technol 125: 104526. https://doi.org/10.1016/j.tust.2022.104526
Wang W, Pan Y, Xiao Y (2022) Synergistic resin anchoring technology of rebar bolts in coal mine roadways. Int J Rock Mech Min Sci 151: 105034. https://doi.org/10.1016/j.ijrmms.2022.105034
Zhang G, He M, Yu X, et al. (2011) Research on the technique of no-pillar mining with gob-side entry formed by advanced roof caving in the protective seam in Baijiao Coal Mine. J Min Saf Eng 28(4): 511–516. (In Chinese)
Zhang X, He M, Yang J, et al. (2020) An innovative non-pillar coal-mining technology with automatically formed entry: a case study. Engineering 6(11): 1315–1329. https://doi.org/10.1016/j.eng.2020.01.014
Zhang X, Hu J, Xue H, et al. (2020) Innovative approach based on roof cutting by energy-gathering blasting for protecting roadways in coal mines. Tunn Undergr Space Technol 99: 103387. https://doi.org/10.1016/j.tust.2020.103387
Zhang X, Pak R, Gao Y, et al. (2020) Field experiment on directional roof presplitting for pressure relief of retained roadways. Int J Rock Mech Min Sci 134: 104436. https://doi.org/10.1016/j.ijrmms.2020.104436
Zhang Y, Zhao C, Jiang M, et al. (2020) Constant-resistance, rigid, and flexible coupling support technology for soft rock entrances in deep coal mines: A case study in China. Adv Mater Sci Eng 1–15. https://doi.org/10.1155/2020/6212456
Zhao C, Sun X, Zhang Y, et al. (2021) Optimization analysis of NPR cable support considering bearing structure in the NSF condition of deep shaft based on Daqiang coal mine. Arab J Geosci 14:1942. https://doi.org/10.1007/s12517-021-08274-x
Zhao S (2016) Experiments on the characteristics of thrust fault activation influenced by mining operation. J Min Saf Eng 33(2): 354. (In Chinese) https://doi.org/10.13545/j.cnki.jmse.2016.02.026
Zhou K, Dou L, Li X, et al. (2022) Coal burst and mining-induced stress evolution in a deep isolated main entry area - a case study. Eng Fail Anal 137. https://doi.org/10.1016/j.engfailanal.2022.106289
Acknowledgments
This research was funded by the National Natural Science Foundation of China (52174096, 42277174), the Fundamental Research Funds for the Central Universities (2022YJSSB03), and the Scientific and Technological Projects of Henan Province (232102320238).
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Sun, Xm., Wang, J., Zhang, Y. et al. Stability control measures for roof cutting and NPR supporting of mining roadways in fault areas of kilometre-deep coal mine. J. Mt. Sci. 20, 3051–3065 (2023). https://doi.org/10.1007/s11629-023-8152-0
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DOI: https://doi.org/10.1007/s11629-023-8152-0