离层注浆开采关键层变形特征及地表沉陷控制效应  

Deformation characteristic of key strata and control effect of surface subsidence in mining with grouting into overburden bed-separation

作　　者：徐良骥[1,2,3] 张坤 刘潇鹏[1,4] 陈宝宝 范廷玉 桂松[5] XU Liangji;ZHANG Kun;LIU Xiaopeng;CHEN Baobao;FAN Tingyu;GUI Song(State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China;Institute of Energy,Hefei Comprehensive National Science Center,Hefei 230031,China;National Engineering Laboratory for Protection of Coal Mine Eco-Environment,Huainan 232001,China;School of Geomatics,Anhui University of Science and Technology,Huainan 232001,China;School of Earth and Environment,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]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,安徽淮南232001 [2]合肥综合性国家科学中心能源研究院,安徽合肥230031 [3]煤矿生态环境保护国家工程实验室,安徽淮南232001 [4]安徽理工大学空间信息与测绘工程学院,安徽淮南232001 [5]安徽理工大学地球与环境学院,安徽淮南232001

出　　处：《煤炭学报》2023年第2期931-942,共12页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(52104172);安徽省重点研发计划资助项目(201904b11020015);深部煤矿采动响应与灾害防控国家重点实验室开放基金资助项目(SKLMRDPC21KF19)。

摘　　要：为研究覆岩离层注浆开采条件下关键层变形特征及地表沉陷控制效应,准确预计地表移动变形值,对离层注浆开采关键层变形进行了力学分析,将关键层下方离层注浆充填体和煤岩体的组合视为弹性地基,并将之划分为压实区、欠压实区和实体煤区3种不同的区段,基于弹性地基梁理论,给出了关键层挠度方程和弹性地基系数计算方法;采用“两步法”,通过分层模拟的方式开展了离层注浆开采关键层变形与地表沉陷数值模拟,研究了不同工作面宽度条件下离层发育和关键层破断特征,以及不同注采比条件下地表移动变形特征;借鉴等价采高理论,将离层注浆开采条件下关键层弯曲下沉空间等效视为开采空间,结合概率积分法,建立了适用于离层注浆开采的地表沉陷预计模型。以淮北矿区袁店二矿7221离层注浆开采工作面为例进行了验证,结果表明:该地质条件下,离层注浆开采工作面宽度宜设计在90~120 m;采用提出的预计模型和方法能够对离层注浆开采条件下的地表沉陷进行有效预计,预计值与实测值平均误差9 mm,在允许误差范围内;离层注浆开采地表沉陷控制效果显著,减沉率约83%。In order to study the deformation characteristic of key strata and control effect of surface subsidence[JP3]in mining with grouting into overburden bed-separation,and predict the surface movement and deformation accurately,the mechanical analysis of key strata deformation was carried out based on the elastic foundation beam theory,and the combination of filling body in bed-separation and coal-rock mass under the key strata was divided into solid coal area,under-compaction area and compaction area,of which the deflection equation of each section of key strata and the calculation method of elastic foundation coefficients were given respectively;By means of simulation layer-by-layer,numerical simulation on the deformation of key strata and surface subsidence in mining with grouting into bed-separation was carried out,the development characteristics of bed-separation,the fracture characteristics of key strata,and the surface movement and deformation characteristics under different injection-production ratios were studied;The bending subsidence space of key strata in mining with grouting into bed-separation was regarded as the mining space with reference to the theory of equivalent mining height,and the surface subsidence prediction model suitable for mining with grouting into bed-separation was established,combined with the probability integral method.It was verified in a mining face with grouting into bed-separation in Huaibei Mining Area,the results showed that the face width should be designed within the range of 90-120 m under the geological condition in the study area;The average error between the predicted value and the measured value was 9 mm,within the allowable error range;The surface subsidence control effect of mining with grouting into bed-separation was remarkable,and the subsidence reduction rate was about 83%.

关 键 词：地表沉陷控制 离层注浆 关键层 力学分析 预计模型 

分 类 号：TD325[矿业工程—矿井建设]