赵庄煤矿断裂构造对围岩稳定性影响研究

发布时间：2018-03-11 17:15

本文选题：断裂构造　切入点：应力场　出处：《太原理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：岩体是由岩块和结构面网络组成,并赋存于一定环境中的地质体,因此岩体的力学特性必然受到结构面切割下的岩体结构以及岩体所处应力环境的影响。岩体的结构特性是岩体稳定的物质基础,初始应力(地应力)状态是应力边界条件,这是决定岩体稳定的两个主要地质因素。断裂构造对地下工程围岩稳定性的影响主要体现在两方面：其一,断裂构造附近的地应力大小及方向会发生变化,导致其周围应力场不同于区域应力场,进而影响围岩应力状态；其二,断裂构造会使岩体表现出不同的结构特征,从而使围岩结构产生不同。在岩体工程中,断裂构造控制着工程岩体的边界条件和破坏方式,及岩体的结构、完整性和物理力学性质。断裂构造的延展长度、切割深度、力学性质等不尽相同,因此本文所指断裂构造是：煤矿井工开采常见的、在采掘活动中可以看清全貌的中小型断层(落差介于5-20m的为中型断层,落差小于5m的为小型断层)、区域节理、控制围岩结构及完整性的节理等断裂构造。本文基于赵庄矿断层、节理发育的地质条件,围绕煤矿井下常见断裂构造,采用现场实测、围岩力学参数试验、理论分析及数值模拟等方法,主要研究了断裂构造对岩体应力场及巷道围岩稳定性的影响、断裂构造对工作面顶板结构及稳定性的影响,主要研究成果如下：(1)通过赵庄矿现场调研观测及岩石力学测试,得出赵庄矿地质构造发育特征及围岩强度参数；(2)通过数值模拟试验研究了断裂构造对岩体应力场的影响,进而分析了巷道轴向与最大水平构造应力夹角a对巷道稳定性的影响,得出了巷道轴向与最大水平主应力方向呈不同夹角情况下的巷道围岩应力分布及破坏特征；(3)通过现场实测、理论分析总结出赵庄矿节理发育直接顶发生端面冒漏的两种类型,建立了直接顶的碎裂结构、块裂结构模型,利用块体理论分析了两模型的稳定性；(4)通过理论分析研究了断层对老顶稳定性影响,得出了断裂面的倾角满足老顶的三铰拱平衡结构条件,老顶不会失稳,当断裂面强度满足库伦-纳维尔准则,老顶不会失稳；利用数值模拟得出了上盘工作面与下盘工作面超前支承压力变化特征及顶板下沉量变化,验证了理论分析的正确性；(5)通过赵庄矿1306工作面遇断裂构造期间的矿压实测,得出工作面遇断裂构造地段的矿压显现特征。
[Abstract]:Rock mass is a geological body which consists of rock blocks and structural plane networks and exists in a certain environment. Therefore, the mechanical properties of rock mass must be influenced by the structure of rock mass cut by structural plane and the stress environment of rock mass. The structural characteristic of rock mass is the material foundation of rock mass stability, and the initial stress (ground stress) state is the stress boundary condition. These are two main geological factors that determine the stability of rock mass. The influence of fault structure on the stability of surrounding rock mass of underground engineering is mainly reflected in two aspects: first, the magnitude and direction of geostress in the vicinity of fault structure will change. As a result, the surrounding stress field is different from the regional stress field, which affects the stress state of surrounding rock. Secondly, the fracture structure will make the rock mass exhibit different structural characteristics, thus make the surrounding rock structure different. The fracture structure controls the boundary condition and failure mode of the engineering rock mass, and the structure, integrity and physical and mechanical properties of the rock mass. The extension length, cutting depth and mechanical properties of the fracture structure are different. Therefore, the fault structure in this paper is: the small and medium faults which are common in coal mining and can be seen clearly in the mining activities (the middle fault with the drop between 5-20 m and the small fault with the drop less than 5 m, the regional joint, etc.). Based on the geological conditions of fault and joint development in Zhaozhuang Mine, the common fracture structures in underground coal mine are measured in the field, and the mechanical parameters of surrounding rock are tested, based on the fracture structure that controls the structure and integrity of surrounding rock. The influence of fracture structure on the stress field of rock mass and the stability of roadway surrounding rock is studied by means of theoretical analysis and numerical simulation, and the influence of fracture structure on roof structure and stability of working face is also studied. The main research results are as follows: (1) through site investigation and observation and rock mechanics test of Zhaozhuang Mine, the geological structure development characteristics and surrounding rock strength parameters of Zhaozhuang Mine are obtained. The influence of fracture structure on rock mass stress field is studied by numerical simulation test. Furthermore, the influence of the angle a of axial and maximum horizontal stress on the stability of roadway is analyzed. The stress distribution and failure characteristics of roadway surrounding rock with different angles of axial direction and maximum horizontal principal stress direction are obtained. On the basis of field measurement, two types of leakage occurred directly at the top of joint development in Zhaozhuang Mine are analyzed and summarized theoretically. The cataclastic structure and block fracture structure model of the direct roof are established, and the stability of the two models is analyzed by using the block theory. (4) the influence of faults on the stability of the main roof is studied by theoretical analysis. It is concluded that the inclined angle of the fracture surface satisfies the equilibrium structural conditions of the main roof of the three-hinged arch, and the main roof will not be unstable, if the strength of the fault surface meets the Coulom-#internal_person0# criterion, the main roof will not be unstable. By using numerical simulation, the variation characteristics of leading support pressure and the change of roof subsidence in upper and lower face are obtained, which verifies the correctness of theoretical analysis and verifies the correctness of theoretical analysis. The measured rock pressure is measured during the fracture structure period of 1306 face in Zhaozhuang Coal Mine. The characteristics of the rock pressure in the fault structure section of the working face are obtained.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD322.4;TD164.1

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