摘要
急倾斜煤层开采后岩层移动及地表沉陷规律较为复杂,而且多煤层开采诱发重复采动会加剧地表变形,但是目前急倾斜多煤层开采岩层移动规律和地表变形特征的研究并不充分,深入研究急倾斜多煤层开采引起的岩层移动及地表变形规律,对煤矿安全生产和地表建筑物稳定性评价具有重要意义。以淮南矿区八里塘东三采区为研究背景,采用3DEC数值模拟软件对急倾斜多煤层深部开采岩层移动及地表变形进行了数值计算分析,得到了急倾斜多煤层开采覆岩移动规律及地表变形特征。计算结果发现:急倾斜煤层开采岩层移动形式可分为顶板岩层的压弯变形、沿弱面的滑移运动以及覆岩直接垮落;急倾斜煤层开采之后,采空区深部岩体运动趋势缓于较上部岩体运动,覆岩主要变形位置在采空区中部,变形方向沿煤层顶板法线方向指向采空区;急倾斜多煤层开采会导致地表松散层变形剧烈,地表下沉曲线及地表倾斜曲线呈现明显的非对称性,且煤层顶板侧地表变形影响范围大于煤层底板侧地表影响范围。根据计算结果,该区域开采后地表最大位移量可达40.625m,地面下沉曲线中没有平底部分,只存在单一最大下沉点,最大下沉点南侧最大倾斜值1.26m/m,北侧最大倾斜值为-0.74m/m,地表倾斜变形曲线呈现以最大下沉点为中心的反对称形态。该研究成果可为八里塘采区类似急倾斜煤层开采研究提供理论依据与技术参考。
The law of rock strata movement and surface subsidence after mining of steeply inclined coal seams is relatively complex, and repeated mining induced by mining of multiple coal seams will aggravate surface deformation. However, the research on the rock movement law and surface deformation characteristics of sharply inclined multi-seam mining is not sufficient. In depth study on the law of rock strata movement and surface deformation caused by mining of steeply inclined multiple coal seams is of great significance to the safety production of coal mines and the stability evaluation of surface buildings. This paper takes the East Third mining area of Balitang in Huainan mining area as the research background. Using 3DEC software, the rock stratum movement and surface deformation of deep mining in multi-steep-seam are numerically calculated and analyzed, and the characteristics of overburden movement and surface deformation in steep multi seam mining are obtained. According to the calculation results, the maximum displacement of the ground surface in this mining area after mining can reach 40.625m, there is no flat bottom part in the ground sinking curve, only a single maximum sinking point exists, the maximum sinking point has a maximum tilt value of 1.26m/m on the south side and-0.74m/m on the north side, and the surface tilt deformation curve shows an anti-symmetric pattern centered on the maximum sinking point. The result shows that the movement forms of strata in steeply inclined coal seam mining can be divided into bending deformation of roof strata, sliding movement along weak plane and direct collapse of overburden;After the mining of steeply inclined coal seam, the movement trend of deep rock mass in goaf is slower than that of upper rock mass. The main deformation position of overburden is in the middle of goaf, and the deformation direction points to goaf along the normal direction of coal seam roof;The mining of steeply inclined multi coal seams will lead to severe deformation of surface loose layer, and the surface subsidence curve and surface inclination curve show obvious asymmetry, and the influence range of surface deformation on the side of coal seam roof is greater than that on the side of coal seam floor. The research results can provide a theoretical basis for the stability of the East Third mining area of Balitang in the Huainan mine.
作者
王海
杨朝晖
李文强
王汉斌
Wang Hai;Yang Zhaohui;Li Wenqiang;Wang Hanbin(Shanxi Transportation Planning Survey and Design Institute Co.,Ltd.,Taiyuan,Shanxi 030032;Engineering and technology research center of highway,Bridge and Tunnel Engineering in Goaf Area of Shanxi,Taiyuan,Shanxi 030032;School of Engineering and Technology,China University of Geosciences(Beijing),Beijing,100083)
出处
《中国煤炭地质》
2022年第12期62-67,80,共7页
Coal Geology of China
基金
山西交科集团2020年度创新发展项目(20-JKCF-42)。
关键词
急倾斜多煤层
岩层移动
地表变形
离散元方法
steep multi seam
overburden movement
surface deformation
discrete element numerical simulation
