基本顶破断位置对煤柱稳定性影响及沿空掘巷支护研究

发布时间：2018-03-11 10:03

本文选题：沿空掘巷　切入点：窄煤柱　出处：《湖南科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：沿空掘巷作为煤矿回采巷道的一种主要布置形式,正被广泛的应用于各类煤矿。沿空巷道窄煤柱的稳定性及巷道支护技术的研究也是国内外学者关注的难点。本文以曲江矿603工作面回风巷为工程背景,采用理论分析、数值模拟以及现场试验相结合的方法,分析了沿空掘巷基本顶破断对窄煤柱稳定性的影响,并对沿空巷道支护技术进行了全面的研究。建立沿空巷道围岩结构力学模型,运用力学理论推导出基本顶五种不同破断位置时煤柱荷载的计算公式。可知增强实体煤帮支护强度,减小巷道高度,可减小煤柱的变形。通过比较可知:基本顶断裂关键块不能形成铰接结构时,煤柱变形最小;若基本顶断裂时关键块形成铰接结构,关键块B断裂于煤柱外侧时对巷道围岩稳定性最有利,断裂于巷道上方时对巷道围岩稳定性最不利。运用UDEC软件模拟了五种破断位置时窄煤柱变形情况及应力特征,并分析了窄煤柱宽度、基本顶厚度、巷道高度以及直接顶厚度对窄煤柱稳定性的影响。五种不同破断位置时窄煤柱变形程度从小到大依次为:煤柱外侧(不形成铰接结构),煤柱外侧,实体煤上方,窄煤柱上方,巷道上方。总结了曲江矿沿空掘巷围岩破坏的几种表现形式;提出采用高预应力桁架锚索梁的支护方式,并分析了桁架锚索梁的支护机理和沿空掘巷巷道的支护原理,采用桁架锚索梁支护后巷道围岩的变形得到了有效的控制。结合数值模拟和理论计算方法分别对煤柱合理宽度进行计算,经过对比分析最终优选出5m为最合理的宽度;现场实测推断曲江矿603工作面基本顶破断位置在窄煤柱外侧;根据曲江矿603工作面回风巷道的实际情况,在原支护方案基础上针对性的提出在顶板采用“锚杆(索)+金属网+桁架锚索梁”联合支护,窄煤柱帮采用“锚杆+金属网+桁架锚索梁”联合支护,实体煤帮则采用“锚杆+金属网+梯子梁”的支护方法,该方案在现场取得了良好的支护效果。
[Abstract]:As one of the main layout forms of mining roadway along goaf, It is widely used in all kinds of coal mines. The stability of narrow pillar along goaf roadway and the research of roadway support technology are also the difficulties concerned by scholars at home and abroad. This paper takes the return air roadway of No. 603 face of Qujiang Mine as the engineering background and adopts theoretical analysis. Combined with numerical simulation and field test, this paper analyzes the influence of the breakage of roadway along goaf on the stability of narrow coal pillar, and makes a comprehensive study on the supporting technology of roadway along goaf, and establishes the structural mechanics model of surrounding rock along goaf roadway. Based on the mechanical theory, the formulas for calculating the load of coal pillar at five different breaking positions of the basic roof are derived. It is known that the support strength of solid coal side is enhanced and the height of roadway is reduced. The deformation of coal pillar can be reduced by comparison: when the key block of basic top fracture can not form hinged structure, the deformation of coal pillar is minimum; if the key block of basic top fracture forms hinge structure, The stability of roadway surrounding rock is most favorable when the key block B fracture is outside the coal pillar and the most disadvantageous to the surrounding rock stability of roadway when the fault is above the roadway. The deformation and stress characteristics of narrow coal pillar in five broken positions are simulated by UDEC software. The width and the basic top thickness of the narrow coal pillar are analyzed. The influence of roadway height and direct top thickness on the stability of narrow coal pillar. The deformation degree of narrow coal pillar changes from small to large in order of five different breaking positions: outside of coal pillar (without hinged structure, outside coal pillar, above solid coal and above narrow coal pillar). Above the roadway, this paper summarizes several forms of failure of surrounding rock along the goaf roadway in Qujiang Mine, puts forward the supporting mode of high prestressed truss anchor cable beam, and analyzes the supporting mechanism of truss anchor cable beam and the supporting principle of roadway along the goaf. The deformation of surrounding rock of roadway is controlled effectively by using truss anchor cable beam support. The reasonable width of coal pillar is calculated by numerical simulation and theoretical calculation method. Through comparison and analysis, 5 m is selected as the most reasonable width. It is inferred that the breaking position of 603 face in Qujiang Coal Mine is outside the narrow pillar, and according to the actual situation of return air roadway in 603 face of Qujiang Coal Mine, Based on the original support scheme, the combined support of "anchor rod (cable) metal mesh truss cable beam" and "anchor rod metal mesh truss anchor cable beam" is put forward in the roof, and the narrow coal pillar side is supported by "anchor rod metal mesh truss anchor cable beam". The solid coal side adopts the support method of "bolt metal mesh ladder beam", and the scheme has good support effect on the spot.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD353

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