State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines, Anhui University ofScience & Technology
Key Laboratory of Safe and Effective Coal Mining Ministry ofEducation, Anhui University of Science & Technology
Mining EngineeringPost-Doctoral Flow Station, Anhui University of Science & Technology
Post-Doctoral Research Station, Huainan Mining Industry (Group) Co Ltd
Post-Doctoral Research Station, Huaibei Mining Corporation Limited

为研究深井坚硬顶板综放开采覆岩裂隙演化规律,将布里渊散射的光频域散射技术(BOF-DA)应用于物理相似模型试验。以千米深井信湖煤矿首采综放工作面地质条件为工程背景,在实验室构建采场覆岩模型,通过预先埋设的传感光纤,探究回采过程中覆岩变形与光纤应变的响应特征。设计了2个钻孔并将光纤植入工作面顶板,实现了采场顶板走向65m、倾向24.5m、垂高119m空间范围内覆岩运移破断规律的监测,获得了工作面推进期间采场顶板光纤的应变数据。结果表明:光纤应变曲线与覆岩变形特征存在明显对应关系;覆岩离层、断裂、切落点光纤应变呈现凸峰状,可以表征采场覆岩“横三区,竖三带”边界特征演化过程;光纤应变曲线凸峰范围和峰值大小变化与采场覆岩运移强度发展趋势基本一致;基于光纤应变与覆岩结构演化的响应关系,结合818工作面覆岩岩性组合,分析现场光纤应变数据确定的工作面“三带”高度与模型试验、理论计算数值吻合,符合矿井实际情况,验证了分布式光纤监测技术在深井坚硬顶板覆岩结构演化监测中的可靠性与准确性。试验结果可为类似条件下采场覆岩变形移动规律的研究提供参考。

To examine the evolution of overburden fissures in deep well hard top slab comprehensive re- lease mining, the optical frequency domain scattering technique for Brillouin scattering (BOFDA) is ap- plied to the physical similar model test. With the geological conditions of the first mining integrated working face of the 1 000-meter-deep shaft Xinhu coal mine as the engineering background, an overlying strata model is established in the laboratory to explore the response characteristics of overburden deformation and fiber strain during the recovery process using pre-buried sensing fibers. The optical fiber sensors are implanted into the working face roof by two boreholes 65 m strike, 24.5 m in- clination, and 119 m vertical to monitor the migration and fragmentation pattern of overlying rock by ob- taining the strain data of the fiber optic of the mining roof during the advance of the working face. The model test results show that there is a correlation between the optical fiber strain curve and the deforma- tion characteristics of the overlying rock. The fiber-optic strain of overburden detachment, fracture, and cut-down point show a convex peak, which can characterize the evolution process of “three horizontal zones and three vertical zones” boundary characteristics of the overburden of the quarry. The variation of the convex peak range and peak size of the optical fiber strain curve is consistent with the development trend of the migration intensity of the overlying rock in the stope. Based on the response relationship be- tween fiber optic strain and overburden structure evolution, combined with the overburden lithology combination of 818 working face, the height of the “three zones” of the working face determined by an- alyzing the field fiber optic strain data is consistent with the model tests and theoretical calculations, which is in line with the actual situation of the mine, and verifies the reliability and accuracy of distribu- ted fiber optic monitoring technology in monitoring the structural Evolution of the overburden of the hard roof of deep shafts. The test results can serve as a reference for the study of the deformation and move- ment law of the overlying rock in the stope.

国家自然科学基金项目(52004005,51774012,51974009);安徽省科技重大专项项目(202203a07020011);安徽省“特支计划”的领军人才项目(T000508);高校协同创新项目(GXXT-2021-075);高校优秀拔尖人才培育项目(gxbjZD2016051);安徽省自然科学基金项目(2008085QE222,2208085QE143);安徽省博士后基金项目(2021B513);安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室自主课题项目(SKLMRDPC19ZZ012);淮北市重大科技专项项目(Z2020005)