舒兰市东富村采空区地表沉降变形研究

发布时间：2018-05-03 18:31

本文选题：采空区 + 沉陷盆地　；参考：《吉林大学》2017年硕士论文

【摘要】：我国是煤炭资源消费大国也是原煤开采大国,因煤炭开采导致的土地沉陷面积正在逐年增加。由于煤炭开采过程而导致的区域的水文地质环境发生破坏和地表沉陷区的形成,严重破坏了地区的生态环境,造成地表农业欠收、建筑物与道路塌陷等一系列环境恶化现象。因此需要对采空区的地表影响范围进行计算分析,为恢复治理提供依据。本文以吉林省舒兰矿业集团东富二矿所在的舒兰市东富村地表沉陷变形情况为研究对象,分析了研究区地质条件和采空区条件对采空区地面沉陷的影响。对研究区的地表变形情况进行了详细的勘察,确定了已有地面变形危害分布范围,并确定了不同地表变形现象的成因机制。根据研究区多层煤层采空区的位置和规模,并结合已有成果和研究区实际地质条件确定概率积分法所需的计算参数,然后分别计算了各采空区的最大可能沉陷值和影响区域,再运用叠加法,根据计算结果绘制出各煤层采空区的最大可能沉陷盆地和综合研究区所有煤层采空区的最大可能沉陷盆地。并分别分析了各煤层采空区所形成的沉陷盆地对研究区的影响,并结合研究区所有采空区沉陷盆地特征和研究区现有地表沉陷特征,确定了研究区沉陷趋于稳定区域和沉陷变形发展区域。运用FLAC3D程序对研究区进行三维数值模拟计算,分析研究区的最大可能沉陷形态。选用霍克-布朗模型作为研究区岩层模拟的本构模型,选用莫尔-库伦模型作为研究区土层模拟的本构模型。数值模拟模型的强度参数由室内岩土体试验、以及基于实际地质情况选择的霍克-布朗强度经验参数确定。根据研究区煤层采掘平面图和地质剖面图拟合地层起伏变化,并将研究区地表地形特征和岩层起伏形态反应到建立的数值模拟模型中。分析了两种方法计算结果的不同,认为这主要由于概率积分法未考虑采空区间的相互作用和对研究区地质参数进行均质化、单一化选取,相比数值计算方法的结果更具有实际意义。最后运用FLAC3D程序模拟分析了地形形态和煤层倾角的变化对采空区沉陷盆地的影响。共建立3组对比实验,共10个数值模型进行分析。分别研究了:地表地形不变,采空区在地表斜坡体的平面相对位置变化时沉陷盆地的变化;采空区的位置不变,地表斜坡体在不同坡度时沉陷盆地的变化;地表地形不变,煤层倾角变化时沉陷盆地的变化。并确定了各因素对采空区沉陷盆地的影响程度,探讨了产生影响的原因。
[Abstract]:China is a big country of coal resource consumption and raw coal mining. The land subsidence area caused by coal mining is increasing year by year. As a result of the coal mining process, the hydrogeological environment of the area is destroyed and the surface subsidence area is formed, which seriously destroys the ecological environment of the area, resulting in a series of environmental deterioration phenomena, such as the underharvest of surface agriculture, the collapse of buildings and roads, and so on. Therefore, it is necessary to calculate and analyze the surface influence range of goaf to provide basis for restoration and control. In this paper, the deformation of surface subsidence in Dongfulcun, Shulan City, Jilin Province, is studied, and the influence of geological conditions and goaf conditions on surface subsidence in goaf is analyzed. In this paper, the ground deformation in the study area is investigated in detail, and the distribution range of ground deformation damage is determined, and the cause mechanism of different surface deformation phenomena is determined. According to the position and scale of the goaf in the multi-layer coal seam in the study area, combined with the existing results and the actual geological conditions of the study area, the calculation parameters needed by the probability integration method are determined, and the maximum possible subsidence value and the influence area of each goaf are calculated respectively. According to the calculation results, the maximum possible subsidence basins in each coal seam goaf and the maximum possible subsidence basins in all coal seam goaf areas in the comprehensive study area are plotted by using superposition method. The influence of the subsidence basins formed in each coal seam goaf on the study area is analyzed, and combined with the subsidence basin characteristics of all the goaf in the study area and the existing surface subsidence characteristics in the study area, The stable subsidence area and the subsidence deformation development area in the study area are determined. In this paper, FLAC3D program is used to simulate the study area, and the maximum possible subsidence shape of the study area is analyzed. The Hawk-Brown model is used as the constitutive model of strata simulation in the study area, and the Mohr Coulomb model is used as the constitutive model of soil layer simulation in the study area. The strength parameters of the numerical simulation model are determined by the indoor rock and soil tests and the Hawk-Brownian strength empirical parameters selected based on the actual geological conditions. According to the mining plan and geological profile of coal seam in the study area, the variation of stratigraphic fluctuation is fitted, and the topographic characteristics and the undulating form of rock layer in the study area are reflected into the established numerical simulation model. The difference between the two methods is analyzed, which is mainly due to the fact that the probabilistic integration method does not consider the interaction between the goaf and homogenize the geological parameters of the study area. Compared with the numerical method, the results are more practical. Finally, the effects of topography and coal seam inclination on the subsidence basin in goaf are simulated and analyzed by FLAC3D program. Three groups of comparative experiments were established and 10 numerical models were analyzed. The subsidence basin changes of goaf in the plane relative position of the surface slope, the subsidence basin with the same goaf position, the subsidence basin change with different slope degree, the surface topographic change with the same surface topography are studied. The change of subsidence basin when coal seam inclination changes. The influence degree of various factors on the subsidence basin in goaf is determined, and the cause of the influence is discussed.
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD325.3

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