【作者】 尹志明；

【导师】 唐建新；

【作者基本信息】 重庆大学 ， 采矿工程， 2010， 硕士

【摘要】 在具有滑坡地形地质条件的山体下采矿而诱发的采动滑坡,是山区地表采动损害的主要形式之一。地下采矿诱发滑坡是一个复杂的力学过程,涉及多方面影响因素,具有多学科交叉性和复杂性。预防采动滑坡的研究涉及到采动坡体稳定性的主要影响因素、地表移动变形、覆岩的移动变化及应力应变关系、采动滑坡的形成机理、坡体稳定性预测、坡体的长期稳定性等一系列问题。本文以四川金刚煤矿马桑湾顺层滑坡为研究对象,调查了金刚煤矿的地形地貌、区域地质背景、地质构造、矿井生产技术条件、马桑湾滑坡的基本情况;分析了采动滑坡的影响因素,并通过理论分析了逆坡开采对坡体稳定性的影响,同时采用室内相似模拟试验研究逆坡开采过程覆岩及坡体的变形破坏规律;运用FLAC-2D软件对马桑湾采动滑坡进行数值模拟,得到采动后的应力位移变化规律;最后对马桑湾采动滑坡进行稳定性计算与评价,得出影响马桑湾滑坡的影响机理。本文主要取得了以下研究成果:(1)从理论上分析了逆坡开采对顺层坡体稳定性的影响,分析结果表明,随着开采不断推进滑体稳定性系数不断的减小,当滑体下缘开始达到充分采动下沉,滑体的稳定性系数最小,之后不再变化,此时坡体是最危险的。(2)相似模拟试验结果表明,缓倾斜煤层开采覆岩的水平移动值较水平煤层开采要大,在开采沉陷的影响下,岩体不断下沉并向煤层倾角方向移动,从而产生下坡方向的剪应力及水平拉应力,坡顶拉应力较大而形成地表裂缝,坡脚有轻微破坏。(3)马桑湾滑坡数值分析结果表明,随着煤层的开采,坡体的应力分布发生较大变化。在坡顶形成拉应力区,坡顶局部拉应力屈服。坡脚压应力及剪应力集中程度明显,并局部发生压剪屈服。(4)由开采强度的计算可知,煤层开采为轻微采动,地下采动对坡体的稳定性的影响较小。根据马桑湾地表移动变形资料可知,马桑湾滑坡区采矿影响程度等级为中等强烈。(5)马桑湾采动坡体的稳定性计算结果表明,在采动影响下坡体稳定性系数不断降低,当内连煤层开采完后处于基本稳定状态,在降雨的作用下稳定性系数进一步下降,导致了滑坡。更多还原

【Abstract】 Landslide caused by mining under mountain with topography and geology condition of landslide is one of the main surface damage of underground mining in mountain area.With the interdisciplinary nature and complexity,landslide induced by underground mining is a complex mechanical process involving many factors.Study of landslide prevention induced by mining involves the slope stability of the main mining factors, ground movement and deformation, overburden movement and stress-strain relationship, the mechanism of mining landslide, slope stability prediction, the long-term slope stability and other issues.By MaSangWan landslide in sichuan JinGang coal mine as the research object, the topography, regional geology background, geological structure, mine production technology, MaSangWan landslide overview of JinGang coal mine were investigated; the impact factors of mining landslide and the slope stability influenced by inverse slope mining were analysised, the law of deformation and failure of overburden and slope by inverse slope mining based on similar simulation test were studyed;By numerical simulation of MaSangWan landslide,we obtained the displacement and the stress variation after mining; Finally, by stability calculation and evaluation of MaSangWan landslide, we obtained the influence mechanism MaSangWan landslide.There main search aehievements are as follows:(1) The analysis of slope stability influenced by inverse slope mining show that with the exploitation, slope stability factor continuously decreased, When the slope is beginning to reach full mining subsidence, landslide stability coefficient reach the minimum, after which no changes, at this point the slope is the most dangerous.(2) The results of similar simulation test shows that horizontal displacement of overburden in gently inclined seam was larger than in horizontal seam, rock sink and move to the seam dip angle influenced by Mining Subsidence,then produced shear stress and horizontal tensile stress, in slope top, the tensile stress is so large as to generating surface cracks, Slight damage in slope toe.(3) Numerical results showed that with coal mining, the slope of the stress distribution changed greatly.In the slope top had a tension stress zone and Local tensile stress yielded.In the slope Toe, stress and shear stress concentration was obvious, and local compression and shear yield. (4) From the calculation of the mining strength we can see, coal mining is a minor mining and underground mining on the stability of the slope was less affected.According to the MaSangWan ground deformation data shows that MaSangWan landslide area’s level of influence was medium strong.(5) MaSangWan slope stability calculation results show that The slope stability factor reduced by the influence of mining.The slope was in basically stable after the interconnect coal mining,and under the influence of rainfall the stability coefficient declined further that leading to landslide.更多还原