摘要
矿井永久硐室作为矿井重要设施,硐室围岩的长期稳定对于煤矿安全生产至为关键。针对益东煤矿煤层中央副水仓围岩失稳大变形难以控制的技术难题,梳理了副水仓硐室围岩现场变形破坏特征,建立UDEC数值计算模型,反演分析了原始混凝土砌碹支护下硐室围岩应力、裂隙发育程度、变形破坏特征,综合分析了副水仓硐室围岩变形破坏机理。结果表明:原始支护强度低、支护系统不协调、底板膨润土遇水膨胀是围岩大变形难以控制的主要原因。结合现场实际条件及数值模拟反演结果,提出了一种“注浆加固+锚杆、索+反底拱”联合支护技术应用于返修实践。现场监测表明:返修后45 d内,两帮收敛量最大为55.8 mm,顶底板移近量最大为46.5 mm,满足副水仓硐室安全使用要求,确保煤矿安全生产。
As an important facility in the mine,the long-term stability of the surrounding rock in the permanent chamber of the mine is crucial for the safe production.In response to the technical problem of instability and difficult control of large deformation of the surrounding rock of the central auxiliary water chamber in Yidong Coal Mine,the deformation and failure characteristics of the surrounding rock of the auxiliary water sump chamber on site were sorted out,a UDEC numerical calculation model was established,and the stress,crack development degree,and deformation and failure characteristics of the surrounding rock of the chamber under the original concrete arch support were analyzed.The deformation and failure mechanism of the surrounding rock of the auxiliary water sump chamber was comprehensively analyzed.The results indicate that the main reasons for the difficulty in controlling the large deformation of the surrounding rock are low original support strength,uncoordinated support system,and expansion of bentonite in the floor stratum when encountering water.Based on the actual on-site conditions and numerical simulation inversion results,a combined support technology of“grouting reinforcement+anchor bolt,cable+reverse arch”was proposed for repair practice.On site monitoring shows that,within 45 days after repair,the maximum convergence of the two sides is 55.8 mm,and the maximum roof-to-floor convergence is 46.5mm,which meets the requirements for safe operation of the auxiliary water sump chamber and ensures the safe production.
作者
伊丙鼎
YI Bingding(Coal Mining Research Institute,China Coal Technology and Engineering Group Co.Ltd.,Beijing 100013,China;Mining and Design Branch,China Coal Research Institute,Beijing 100013,China;State Key Laboratory of Coal Mining and Clean Utilization,Beijing 100013,China)
出处
《煤炭工程》
北大核心
2024年第3期117-123,共7页
Coal Engineering
基金
国家自然科学基金面上项目(52274124)。
关键词
大断面
永久硐室
围岩控制
注浆加固
反底拱
large section
permanent chamber
surrounding rock control
grouting reinforcement
inverted arch
