基于OFDR的采动覆岩铰接结构回转角度及“三带”变形表征研究  

Study on rotation angle and three-zone deformation characterization of hinged structure of mining overburden rock based on OFDR

作　　者：刘奇 刘相林 曹广勇[3] 赵金海[1,2] 蒋长宝 LIU Qi;LIU Xianglin;CAO Guangyong;ZHAO Jinhai;JIANG Changbao(College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China;State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao 266590,China;Anhui Jianzhu University,Anhui Provincial Key Laboratory of Building Structure and Underground Engineering,Hefei 230601,China;College of Resources and Security,Chongqing University,Chongqing 400044,China)

机构地区：[1]山东科技大学能源与矿业工程学院,山东青岛266590 [2]山东省矿山灾害预防控制省部共建国家重点实验室培育基地,山东青岛266590 [3]安徽建筑大学建筑结构与地下工程安徽省重点实验室,安徽合肥230601 [4]重庆大学资源与安全学院,重庆400044

出　　处：《煤炭科学技术》2024年第3期63-73,共11页Coal Science and Technology

基　　金：国家自然科学基金资助项目(51904168),山东省自然科学基金资助项目(ZR202212010234)。

摘　　要：为了研究陕北某矿采动覆岩结构的光纤应变表征方法,基于12217工作面工程地质条件,分析了OFDR(光频域反射技术)的应变监测原理,在采动覆岩运动状态分区和分布式光纤应变监测原理基础上,建立了水平光纤应变表征采动覆岩铰接结构回转角度的力学分析模型,推导出应变峰值宽度与岩层破断后所形成采动覆岩铰接结构回转角度的函数关系,定义了铰接结构回转临界角度的概念,提出了基于光纤应变特性和采动覆岩铰接结构回转角度的覆岩“三带”划分判据,并采用光纤应变表征方法对采动覆岩应变特征进行分析。结果表明:采动覆岩“三带”的不同变形程度与铰接结构回转角度的大小呈正比例关系,因此通过铰接结构回转角度划分“三带”范围是可行的;通过水平光纤应变峰值特性计算铰接结构回转角度,与二维物理相似模型试验的近景摄影测量角度相比,两者平均误差小于1°,验证了提出的光纤应变表征采动覆岩铰接结构回转角度的力学模型有效性。二维物理相似模型得到的垮落带高度和裂隙带高度与该工作面现场结果一致,与理论计算数值吻合,符合该矿实际情况。研究结果为分布式光纤监测技术表征采动覆岩变形特征的应用提供了新的研究思路。In order to study the fiber optical strain characterization method of the overlying rock structure during mining in a certain mine in northern Shannxi,based on the engineering geological conditions of 12217 working face in Buertai Mine,the strain monitoring principle of OFDR(Optical Frequency Domain Reflection Technology)was analyzed.Based on the partition of mining-induced overburden movement state and the principle of distributed optical fiber strain monitoring,a mechanical analysis model of horizontal optical fiber strain to characterize the rotation angle of mining-induced overburden hinged structure was established.The functional relationship between the peak width of strain and the rotation angle of mining-induced overburden hinged structure formed after rock strata were broken was deduced,and the concept of critical rotation angle of hinged structure was defined.Based on the strain characteristics of optical fiber and the rotation angle of hinged structure of mining overburden rock,the criterion of three-zone division of overburden rock is proposed,and the strain characteristics of mining overburden rock are analyzed by means of optical fiber strain characterization method.The results show that the different deformation degree of the three zones of mining overburden is proportional to the rotation angle of the hinged structure,so it is feasible to divide the three zones by the rotation angle of the hinged structure.The rotation angle of the hinged structure is calculated by the peak strain characteristics of the horizontal optical fiber.Compared with the close-range photogrammetry angle of the two-dimensional physical similarity model test,the average error between the two is less than 1°,which verifies the effective-ness of the mechanical model of the proposed optical fiber strain to characterize the rotation angle of the hinged structure of the mining overburden.The height of the caving zone and the height of the fracture zone obtained by the two-dimensional physical similarity model are consistent with

关 键 词：采动覆岩 光频域反射 回转角度 光纤应变 采动“三带” 

分 类 号：TD325[矿业工程—矿井建设]