老沉陷区残余变形对建筑物影响的研究

发布时间：2018-07-01 12:18

本文选题：采煤沉陷区 + 抗变形　；参考：《北方工业大学》2017年硕士论文

【摘要】：近年来,随着矿产资源的大量开采,地表沉陷区越来越多,建筑用地的急剧减少使得地表沉陷区的建筑复垦再利用变得非常重要。由于沉陷区地表存在残余变形,所以既要保证地基的稳定性,又要求建筑物有足够强的抗变形能力。因此,研究老沉陷区的建筑复垦,对沉陷区的再利用具有非常重要的理论意义和实际工程应用价值。抚顺市老虎台矿属巨厚煤层,开采至今100多年,其采空区上方形成一个近三十平方公里的沉陷盆地。结合老虎台矿实际开采情况,根据工程地质资料以及工程实践,利用上部结构与基础及地基共同作用属性,应用理论与实际工程相结合方法对沉陷区中新建筑工程建设的可行性与安全措施进行了系统研究,主要研究内容及结论如下:(1)总结国内外沉陷区复垦研究的现状;根据老虎台矿区实际开采状况,系统分析了地表沉降及其对矿区周边建筑物的破坏影响特点;研究得到老沉陷区地表残余变形规律与地表移动期移动规律相同,预测了地表残余变形量,评估得到煤层开采后地表建筑允许工程建设的最短时间为采后13年;(2)采用煤矸石对沉陷盆地进行回填,施工中采用分层分幅强夯法进行压实,依据现场试验方法确定煤矸石回填地基的承载力大小为220KN;根据计算,建筑附加荷载影响深度和三带破坏高度共223m,小于煤层最小开采深度670m,据此评估回填地基的稳定性,并确定地基建筑复垦利用的可行性,适合建造六层建筑物。(3)工程设计采用六层框架结构,空间对称,采用梁板式筏基。在沉陷区地表选取三个不同工程位置,通过数值模拟分析方法,对相应的不同地表位置上的建筑结构的沉降、倾斜变形、水平变形及曲率变形等进行了研究,分析了建筑结构的应力与应变,计算了建筑结构的安全性,得出在沉陷区中心区域和工作面外拉伸区域建筑物处于稳定状态,工作面内压缩区域只能兴建不高于3层的建筑物;根据模拟分析,采沉区建筑物间的最小前后间距为最高楼高的1.4倍,最小左右间距为楼高的0.5倍。(4)对不能保证建筑物安全的区域进行地基处理,主要采用CFG桩复合地基来协调地基、基础及上部结构间的变形,根据数值模拟方法分析得到复合地基应用于此沉陷区作用效果显著;同时对采沉区建筑结构提出了合理的抗变形保护措施。
[Abstract]:In recent years, with the exploitation of mineral resources, there are more and more subsidence areas on the surface. The sharp decrease of building land makes the reclamation and reuse of surface subsidence areas very important. Because of the residual deformation on the surface of the subsidence area, it is necessary to ensure the stability of the foundation and the strong anti-deformation ability of the building. Therefore, it is of great theoretical significance and practical engineering application value to study the building reclamation of the old subsidence area. Laohutai Coal Mine in Fushun is a very thick coal seam, which has been mined for more than 100 years. A subsidence basin of nearly 30 square kilometers is formed above the goaf. Combined with the actual mining situation of Laohutai Mine, according to the engineering geological data and engineering practice, using the superstructure, foundation and ground interaction attribute, The feasibility and safety measures of new building construction in subsidence area are systematically studied by combining theory with practical engineering. The main research contents and conclusions are as follows: (1) summarize the present situation of reclamation research in subsidence area at home and abroad; According to the actual mining situation in Laohutai mining area, the characteristics of surface subsidence and its damage to buildings around the mining area are analyzed systematically, and it is found that the law of surface residual deformation in the old subsidence area is the same as the movement law during the surface movement period. The residual deformation of the ground surface is forecasted, and the shortest time for the construction of the ground building after coal seam mining is estimated to be 13 years after mining. (2) the coal gangue is used to backfill the subsidence basin, and the stratified dynamic compaction method is used in the construction. According to the field test method, the bearing capacity of coal gangue backfill foundation is determined to be 220 KN. According to the calculation, the influence depth of additional load and the failure height of three zones are 223m, which is less than the minimum mining depth of coal seam 670m, so the stability of backfill foundation is evaluated. The feasibility of reclamation and utilization of foundation building is determined, which is suitable for the construction of six-story buildings. (3) the six-story frame structure, space symmetry and beam-slab raft foundation are adopted in the engineering design. In this paper, three different engineering positions are selected in the subsidence area. The settlement, tilt deformation, horizontal deformation and curvature deformation of the building structures at different surface positions are studied by numerical simulation method. The stress and strain of the building structure are analyzed and the safety of the building structure is calculated. It is concluded that the building is in a stable state in the central area of the subsidence area and outside the working face, and the compressed area in the working face can only build a building of not more than 3 stories. According to the simulation analysis, the minimum distance between the buildings in the mining subsidence area is 1.4 times of the maximum building height, and the minimum left and right distance is 0.5 times of the building height. (4) the ground treatment is carried out in the area which can not guarantee the safety of the building. CFG pile composite foundation is mainly used to coordinate the deformation between foundation and superstructure. At the same time, reasonable anti-deformation protection measures are put forward for building structure in mining subsidence area.
【学位授予单位】：北方工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU196.1

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