煤炭的地下开采，使其上方覆盖岩层失去支撑，岩体内部的原有应力平衡状态受到破坏，引起岩体内应力重新分布，使采空区围岩的移动、变形直至破坏。当采空区面积达到一定的范围后，引起采空区上方地表产生移动和变形，地表的移动与变形严重影响采空区上部建筑物地基，导致了建筑物出现移动、变形，甚至破坏的现象。煤炭开采对地面建筑物造成的有害影响时有发生，给人民财产和生命安全造成很大威胁，因此对采空区上部建筑物地基稳定性进行深入、系统的研究显得尤为重要。本论文依托新疆乌鲁木齐市急倾斜煤层老采空区的具体数据和资料，深入了解和掌握研究采空区围岩移动破坏基本规律、采空区上方地表移动与变形的基本规律和地表破坏基本特征、采空区破裂岩体物理力学特征等理论基础。在分析急倾斜煤层采空区塌陷的力学性质的基础上，将不同的建筑物性质概化为不同的新增荷载，以急倾斜煤层采空区的地质条件为原型条件，借助于FLAC3D软件进行数值模拟计算。数值模拟试验分为四个部分：第一部分模拟开采沉陷过程，系统分析在多层开采条件下，采动覆岩的移动和破坏规律以及地表移动变形规律；第二部分在拟建场地的不同位置施加不同荷载，模拟建筑荷载作用下拟建场地的稳定性。第三部分在拟建建筑区施加均布荷载，模拟建筑物荷载作用下老采空区上方覆岩的“活化”变形及对拟建场地的影响；第四部分对二十年后拟建场地的稳定性进行评价。为采空区地表的利用和建筑物的安全提供理论依据和必要的建议。

Underground coal mining make the overlying strata lose support, rock mass’s original stress balance damaged, stresses in rock mass redistribute and the gob surrounding rock move, deform and damage. With the enlargement of the gob area, above surface will produce deformation. This will seriously affect the upper buildings foundation, and eventually lead to damage to buildings. In-depth and systematic research on Stability of mined-out area overlying strata is particularly important, because of the harmful effects of coal mining on the surface cause great threat to people's property and life safety. This paper is based on the data from the steep coal seam gob area in Urumqi, Xinjiang province, and research on the law of gob surrounding rock movement and destruction, laws of surface’s movement, deformation and damage characteristics above the mined-out area, gob fracture rock mass physical and mechanical characteristics. Analyse the mechanical properties of steep coal seam gob collapse, regard properties of different buildings as different new load. Put the steep coal seam gob geological condition as prototype, do the numerical simulation calculation by means of FLAC3D. Numerical simulation is divided into four parts: first, mining subsidence process simulation, analyse laws of overlying strata’s movement, deformation and damage under multi-layer mining systematically. Second, simulate the stability of the proposed site under construction loads by applying different load in different locations in the proposed site. Third, add the uniformly distributed load on proposed site to simulate overlying strata activation deformation above the gob under this load and effect of the proposed site. Forth, evaluate the stability after 20 years of the proposed site. Provide theoretical basis and advice for the utilization of the surface above mined-out area and building safety.