极近距离煤层综放开采工作面覆岩“两带”发育规律研究  

Study on development regularity of“two zones”in overlying strata with fully mechanized caving mining in extremely contiguous coal seams

作　　者：谷文伟 高召宁[1,2] 李颜 GU Wenwei;GAO Zhaoning;LI Yan(Province and MOE Joint Key Lab of Mine Safety and High Efficient Mining,Anhui University of Science and Technology,Huainan Anhui 232001,China;Anhui Provincial Key Lab of Deep Coal Mines Excavation Response and Disaster Prevention and Control,Anhui University of Science and Technology,Huainan Anhui 232001,China)

机构地区：[1]安徽理工大学煤矿安全高效开采省部共建教育部重点实验室,安徽淮南232001 [2]安徽理工大学深部煤矿采动响应与灾害防控安徽省重点实验室,安徽淮南232001

出　　处：《中国安全生产科学技术》2022年第5期135-142,共8页Journal of Safety Science and Technology

基　　金：国家自然科学基金项目(51174255)。

摘　　要：为深入研究极近距离煤层综放开采工作面覆岩“两带”的动态发育规律,采用理论推导、数值模拟和现场实测相结合的方法,分析袁店一矿824工作面覆岩“两带”的裂隙演化特征。结果表明:从岩层层向拉伸率角度,研究上覆岩层垮落带和导水裂隙带的垮落程度,考虑角度影响推导出岩层弯曲下沉边缘段变形前后的长度计算公式,根据覆岩的碎胀特征计算各岩层的最大下沉量,预测垮落带和裂隙带的范围分别为30.2~41.2 m和70.7~78.2 m;采用3DEC数值模拟分析该矿824工作面开挖后上覆岩层垮落的基本形态和裂隙分布规律,结合其应力、位移云图和监测线位移曲线的分布特征,得出垮落带和裂隙带的高度分别为32.50 m和77.25 m;采用分布式光纤应变监测系统,监测工作面前方80 m处上部顶板的受力情况,得出受采动影响的光纤应变呈起伏变化,且应变分布与地层岩性存在对应关系,得出垮落带高度约30.4 m,裂隙带高度约74.8 m,验证采用层向拉伸率和覆岩碎胀性2个方面来预测工作面覆岩“两带”高度的合理性,可为类似方面的研究与施工提供相应的技术依据。In order to further study the dynamic development regularity of“two zones”in the overlying strata with the fully mechanized caving mining in the extremely contiguous coal seams,the fractures evolution characteristics of“two zones”in the overlying strata in No.824 working face of Yuandian No.1 Mine were analyzed by combining the theoretical derivation,numerical simulation and field measurement.The results showed that the stratigraphic stretch rate of overlying strata could be used to study the collapse degree of the collapsed zone and the water-conducting fractured zone in the overlying strata,and the calculation formula for the length before and after the deformation of the bending and sinking edge section of the strata was derived considering the influence of angle,then the maximum subsidence value of each strata was calculated according to the swelling characteristics of overlying strata,and the predicted ranges of collapsed zone and fractured zone were 30.2~41.2 m and 70.7~78.2 m,respectively.The 3DEC numerical simulation was used to analyze the basic morphology and fracture distribution regularity of overlying strata collapse after the excavation of No.824 working face,and combined with the distribution characteristics of the stress,displacement cloud map and monitoring line displacement curve,it was obtained that the heights of collapsed zone and fractured zone were 32.5 m and 77.25 m,respectively.The strain detection system with distributed optical fiber was used to monitor the force of upper roof at 80 m in front of working face,and it was concluded that the fiber strain affected by mining presented the fluctuated change.There was a corresponding relationship between the strain distribution and formation lithology,and the height of collapsed zone was about 30.4 m,and the height of fractured zone was about 74.8 m.The results verified the rationality of predicting the heights of“two zones”by using the stratigraphic stretch rate and the breaking expansion property of overlying strata,and provide t

关 键 词：极近煤层 上覆岩层 “两带”高度 分布式光纤 

分 类 号：X936[环境科学与工程—安全科学] TD327[矿业工程—矿井建设]