Stability mechanism and control of the pumpable supports in longwall recovery room  

作　　者：Dong Zhang Jianbiao Bai Zhijun Tian Zizheng Zhang Yonghong Guo Rui Wang Ying Xu Hao Fu Shuai Yan Min Deng Shuaigang Liu 

机构地区：[1]State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology,Xuzhou 221116,China [2]Key Laboratory of Xinjiang Coal Resources Green Mining,Xinjiang Key Laboratory of Coal-bearing Resources Exploration and Exploitation,Xinjiang Engineering Research Center of Green Intelligent Coal Mining,Xinjiang Institute of Engineering,Urumqi 830023,China [3]Work Safety Key Laboratory on Prevention and Control of Gas and Roof Disasters for Southern Goal Mines,Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines,Hunan University of Science and Technology,Xiangtan 411201,China [4]School of Mines,China University of Mining and Technology,Xuzhou 221116,China

出　　处：《International Journal of Mining Science and Technology》2024年第7期957-974,共18页矿业科学技术学报（英文版）

基　　金：financial support provided by the Xinjiang Uygur Autonomous Region Key R&D Project Task Special-Department and Department Linkage Project(No.2022B01051);Major Project of Regional Joint Foundation of China(No.U21A20107);Hunan Provincial Natural Science Foundation of China(No.2024JJ4021);the Xinjiang Uygur Autonomous Region Tianchi Introduction Plan(No.2024XGYTCYC03)。

摘　　要：The load-bearing performance(LBP)of pumpable supports(PPS)is crucial for the stability of longwall pre-driven recovery room(PRR)surrounding rock.However,the unbalanced bearing coefficient(UBC)of the PPS(undertaking unequal load along the mining direction)has not been investigated.A mechanical model of the PRR was established,considering the main roof cantilever beam structure,to derive an assessment formula for the load,the failure criteria,and the UBC of the PPS.Subsequently,the generation mechanisms,and influencing factors of the UBC were revealed.Global sensitivity analysis shows that the main roof hanging length(l_(2))and the spacing between the PPS(r)significantly impact the UBC.A novel design of the PPS and the coupling control technology were proposed and applied to reduce the UBC of the PPS in the adjacent longwall PRR.Monitor results showed no failure of the PPS at the test site,with the UBC(ζ)reduced to 1.1 consistent with the design value(1.15)basically,fully utilizing the collaborative LBP of the PPS.Finally,the maximum roof-to-floor convergence of the PRR was 234 mm,effectively controlling the stability of the surrounding rock of the PRR and ensuring the mining equipment recovery.

关 键 词：Pre-driven recovery room Pumpable supports Unbalanced bearing coefficient Hydraulic fracture Stability analysis Surrounding rock control 

分 类 号：TD355[矿业工程—矿井建设]