复杂地貌下行式开采地表移动变形规律  

Surface Movement and Deformation Law in Downward Mining of Complex Geomorphology

作　　者：董灿灿 吕义清[1] 刘志辉 郑劭铎 DONG Cancan;LYU Yiqing;LIU Zhihui;ZHENG Shaoduo(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;China Institute of Geotechnical Investigation and Surveying,Beijing 100007,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]建设综合勘察研究设计院有限公司,北京100007

出　　处：《煤矿安全》2020年第11期237-242,共6页Safety in Coal Mines

基　　金：山西省自然科学基金资助项目(201701D121015)。

摘　　要：为了研究复杂地貌条件下下行式开采地表移动变形规律,结合山西某煤矿工程地质条件,采用理论分析和FLAC3D数值模拟相结合的方法,通过构建含复杂地貌的三维模型,分析了研究区地表在8^#煤和11^#煤下行式重复采动作用下地表的移动变形特征以及地表坡体失稳破坏机理。结果表明:由于8^#煤层覆岩厚度较小,8^#煤层开采后,采空区上方部分区域断裂带直达地表;8^#煤层底板破坏带深度达16.08 m,对11^#煤顶板稳定性产生一定的影响,但11^#煤开采时仍能形成稳定顶板;8^#煤和11^#采动下地表最大下沉值分别为1.331、1.626 m,地表沉陷范围呈现以采空区为中心的近椭圆形,重复采动下地表移动变形范围变化较小;地表移动变形受到地形的影响,在陡坡地带地表沉陷范围和水平位移均明显增大;地表坡体坡脚处发生剪应力集中,坡体后缘受到拉应力作用,在降雨和震动作用下,坡体易发生破坏形成地质灾害。To study the law of surface movement and deformation in downward mining under complex landform conditions,combined with the engineering geological conditions of a coal mine in Shanxi Province,a combination method of theoretical analysis and FLAC3Dnumerical simulation is used to construct a three-dimensional model with complex landforms.The characteristics of the movement and deformation of the ground surface and the instability and failure mechanism of the surface slope under the 8^#coal and 11^#coal repeated downward mining operation.The results show that due to the small overburden thickness of the 8^#coal seam,after the mining of the 8^#coal seam,the fracture zone in some areas above the goaf reaches the surface directly;the depth of the failure zone of the 8^#coal seam floor is up to 16.08 m,which has a certain effect on the stability of the 11^#coal roof,but the 11^#coal mining can still form a stable roof;the maximum surface subsidence values under the 8^#coal and the 11^#mining are1.331 m and 1.626 m,respectively,and the surface subsidence area presents a near ellipse with the goaf as the center,the deformation range of ground movement under repeated mining changes little;the surface movement deformation is affected by the topography,and the surface subsidence range and horizontal displacement in the steep slope area significantly increase;the shear stress concentration occurs at the foot of the surface slope,and the rear edge of the slope body is subjected to tensile stress.Under the action of rainfall and vibration,the slope is prone to damage and forms the geological disaster.

关 键 词：复杂地貌 下行式开采 三维数值模型 FLAC^3D 覆岩破坏 地表移动变形 

分 类 号：TD325.2[矿业工程—矿井建设]