深部软弱煤岩围岩位移场及应力场分析

发布时间：2018-03-05 02:17

本文选题：围岩应力场　切入点：深部软弱煤岩　出处：《安徽建筑大学》2016年硕士论文　论文类型：学位论文

【摘要】：煤矿的开采改变了原岩地应力场与位移场,使得围岩应力重新分布,应力密集区的高应力会造成煤炭开采巷道的变形破坏,围岩应力场与位移场的分布规律研究对煤矿的安全开采至关重要。对于深部软弱煤岩围岩应力场与位移场的单一的分析探索很少,几乎没有,特此,本篇论文对深部软弱煤岩围岩应力场与位移场做系统多方面的研究,另外,使用传统的深部软弱围岩的应力场与位移场的研究方法,符合不了现代环境的要求,同时也不可以做简洁、精确的探索分析。因此,本文通过数值模拟的五个模型的分析,从而建立对围岩应力场与位移场的分布规律进行研究,为煤矿的安全开采提供理论依据。依据矩形巷道的理论研究,得到其位移场与应力场的基本分布状况,从而发现巷道破坏规律,然后对深部软弱煤岩应力场与位移场的分布进行分析。确定煤岩应力场与位移场分布的影响因素,使用合理的数值计算模型。通过巷道埋深的不同情况作为划分标准。分别取500-1500m的煤岩埋深,使用其相应的地应力12Mpa,14Mpa,16Mp a,18Mpa,20Mpa的五种情况,作为数值模型分析的计算条件,同时选用3m×3m的煤岩巷道断面,煤岩岩性使用口孜东矿11-2煤岩。在实验室测定围岩的力学参数,选用摩尔-库伦模型、应变软化模型,同时合理地划分网格;选择竖直与水平方向的网格,得到其位移场与应力场,来判断围岩的塑性圈和松动圈的区域,根据水平与竖直方向的不同的临界点,得出不同埋深的塑性圈和松动圈。依据数值模拟结果,研究竖直与水平方向的应力场与位移场变化的临界点,找出巷道围岩断面最先破坏失稳的关键部位,研究其规律性的结论。得出不同煤岩巷道埋深情况下,塑性圈和松动圈的分布规律。本文采用现场实测、理论分析和数值模拟相结合综合研究方法,对口孜东矿11-2深部软弱煤岩围岩应力场及应力场分布规律进行综合分析。通过现场勘察,阅读文献资料,掌握一定的理论分析方法,结合现场工程地质,明确研究分析方法:数值模拟及现场试验。理论分析采用国内外研究出来的比较成熟的经验公式,得出口孜东矿11-2深部软弱煤岩围岩应力场及应力场的特点;运用数值模拟软件FLAC3D建立需要挖掘的五个模型,获得主应力图、两个方向上的位移变化图,根据不同巷道埋深得出口孜东矿11-2深部软弱煤岩围岩应力场及应力场分布的特点及其分布规律,对更深层次地探索深部软弱煤岩围岩应力场与位移场的活动规律的研究做基础,也对瓦斯和煤炭的安全挖掘做出有意义的参考。
[Abstract]:The mining of coal mine has changed the stress field and displacement field of the original rock, which makes the stress of surrounding rock redistribution, and the high stress in the area with concentrated stress will cause the deformation and destruction of the roadway in coal mining. The study on the distribution of surrounding rock stress field and displacement field is very important to the safe mining of coal mine. In this paper, the stress field and displacement field of deep soft coal rock surrounding rock are systematically studied. In addition, the traditional research methods of stress field and displacement field of deep soft surrounding rock can not meet the requirements of modern environment. Therefore, through the analysis of five models of numerical simulation, the distribution of stress field and displacement field of surrounding rock is studied. According to the theoretical study of rectangular roadway, the basic distribution of displacement field and stress field is obtained, and the damage law of roadway is found. Then, the distribution of stress field and displacement field in soft coal and rock is analyzed, and the factors influencing the distribution of stress field and displacement field in coal and rock are determined. The reasonable numerical calculation model is used. According to the different conditions of roadway buried depth as the dividing standard, the coal and rock burial depth of 500-1500 m is taken separately, and the corresponding five cases of the geostress 12Mpa-14Mpa-14Mpa-16Mpa-18Mpa-20Mpa are used as the calculation conditions for the numerical model analysis. At the same time, the coal and rock roadway section of 3m 脳 3m is selected, and the coal and lithology of Kou Zidong Mine 11-2 is used. The mechanical parameters of surrounding rock are measured in laboratory, the Moor-Coulomb model and strain softening model are selected, and the mesh is reasonably divided. The displacement field and stress field of the vertical and horizontal grid are selected to judge the area of the plastic circle and the loose circle of surrounding rock, according to the different critical points in the horizontal and vertical directions, The plastic circle and loose circle with different buried depths are obtained. Based on the results of numerical simulation, the critical point of the change of vertical and horizontal stress field and displacement field is studied, and the key position of failure and instability of roadway surrounding rock section is found out. The distribution law of plastic circle and loose circle is obtained under different coal and rock roadway depth. In this paper, the method of field measurement, theoretical analysis and numerical simulation is used to study the distribution of plastic circle and loosening zone. The stress field and stress field distribution law of deep soft coal and rock surrounding rock of 11-2 deep soft coal mine are analyzed synthetically. Through site investigation, reading literature, mastering certain theoretical analysis method and combining with field engineering geology, this paper analyzes the stress field and stress field distribution of 11-2 deep soft coal rock. The research and analysis methods are as follows: numerical simulation and field test. The characteristics of stress field and stress field in the surrounding rock of 11-2 deep weak coal and rock are obtained by using the relatively mature empirical formula developed at home and abroad. Using the numerical simulation software FLAC3D to build five models that need to be excavated, the principal stress map and the displacement change diagram in two directions are obtained. According to the characteristics and distribution law of stress field and stress field distribution in the surrounding rock of 11-2 deep soft coal and rock in different roadway buried depth, this paper makes a foundation for further research on the activity law of stress field and displacement field in deep soft coal rock surrounding rock. It also makes a meaningful reference for the safe excavation of gas and coal.
【学位授予单位】：安徽建筑大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD325

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