【作者】 刘倡清；

【导师】 杨更社；

【作者基本信息】 西安科技大学 ， 岩土工程， 2011， 博士

【摘要】 综放工作面回采巷道的围岩稳定性评价、破坏模式、破坏规律以及其控制技术研究是煤矿支护中的关键科学问题之一。开展综放变宽度煤柱回采巷道围岩破坏规律及其控制技术研究具有重要的理论意义和工程应用价值。论文以靖远煤业集团魏家地煤矿综放工作面回采巷道为依托,采用室内及现场试验、理论分析、FLAC数值模拟等手段研究了采区动压巷道的围岩破坏规律,分析了围岩的破坏模式,提出了巷道稳定性控制措施。魏家地煤矿一层煤综放开采条件下,沿倾斜煤层边缘的塑性区宽度为7.8m,保证护巷煤柱稳定的煤柱宽度应在17m以上。煤层的竖向应力峰值和水平应力峰值呈非耦合分布。综放变宽度煤柱回采巷道在煤柱宽度由窄变宽的过程中,煤柱内压应力满足从“缓丘形”到“单峰形”,再到“非对称双峰形”,最后达到“非对称单峰形”的规律。巷道顶板压力峰值的变化满足从开始的“逐渐远离”到“反向跳跃”,直到最后达到“基本静止”的规律。得到了不同宽度煤柱的破坏模式和变形特征,在煤柱宽度由窄变宽的过程中,煤柱的破坏形态由“煤柱全部破坏”向“N形破坏”、棱形破坏、楔形破坏转化。魏家地煤矿综放工作面合理的煤柱宽度为20m。随着煤柱宽度的增加,巷道的稳定性满足从“稳定”到“不稳定”,直到“稳定”的规律。分析了不同加固措施对变宽度煤柱回采巷道围岩变形控制的力学机理。完成了变宽度煤柱的破坏特性和巷道的稳定性评价研究,提出了受采动影响巷道锚网支护设计准则。基于信息化设计基本理论,建议对巷道重要部位在关键时期进行有效控制,提出了以加固变宽度煤柱为主、复合锚网支护巷道为辅的综合围岩控制技术。运用三维有限差分软件对锚网支护方案进行了优化模拟,得到合理的锚网支护参数,现场实践表明锚网支护方案的优化结果是合理可行的。变宽度煤柱回采巷道围岩变形破坏规律及其支护技术研究富有理论价值和实际指导意义。研究成果为类似条件下的巷道变形控制提供了科学依据。更多还原

【Abstract】 Analysis of surrounding rock stability, failure mode, failure pattern and its controlling technique of roadway in fully-mechanized sub-level caving mining face is one of key Scientific problem in coal mine supporting. It has important theory sense and engineering applying value to make a research on surrounding rock failure law and its controlling technique of variable-width coal pillars roadway in fully-mechanized sub-level caving mining face. The thesis takes roadway in fully-mechanized sub-level caving mining face in Wei Jiadi Coal Mine of Jing Yuan Coal Corp. as backing, the measures such as indoor and in-situ test, theoretical analysis, FLAC numerical simulation and so on were adopted to study surrounding rock destroying law in mining area of dynamic pressure roadway. The surrounding rock destroying mode was analysed and controlling measures of roadway stability was provided.Under the fully-mechanized exploiting condition of first layer of coal seam in Wei Jiadi Coal Mine, the plasticity area width along inclined coal seam border is 7.8m, the coal pillars width which makes protected coal pillars stable is above 17 m. The vertical stress peak value of coal seam is not couple with horizontal stress peak value. In the narrow to broad changing process of coal pillars, the compressive stress curve in coal pillars according to the law that is“slow mound shape”to“unimodal shape”, then to“asymmetric bimodal type”, and finally to“asymmetric unimodal shape”, and the pressure alteration of roadway roof meet the law of“gradually far away”to“inverted leaping”and finally to“fundamental motionless”.Destroying pattern and deformable characteristic with different width coal pillars were obtained, and the optimum coal pillars width in sub-level caving mining face was given. In the narrow to broad changing process of coal pillars, the changing law of coal pillars destroying form is coal pillars all destroyed to“N shape”destroyed to edge shape destroyed to cuneiform destroyed, and the rational width of coal pillars in fully-mechanized sub-level caving mining face in Wei Jiadi Coal Mine is 20m. The roadway stability is transferred according to the pattern of“stable to unsteady to stable”with the increase of coal pillars width.The mechanical mechanism of different consolidating measure controlling surrounding rock deformation of roadway with variable-width coal pillars was analysed. Destroying characteristic of variable-width coal pillars and stability evaluation of roadway were finished, and tunnel anchor net shoring design criteria affected by mining was suggested. Based on the basic theory of informational design, the effective control was suggested to implemented on important location of roadway in key period and synthetical surrounding rock control technique that the consolidation of variable-width coal pillars was given first place and the compound anchor net shoring tunnel is subsidiary was suggested.The three-dimensional finite difference software was applied to carry out the optimization simulation on anchor net shoring scheme, and the rational anchor net shoring parameters can be get. The field practice indicates that the optimization results of anchor net shoring scheme is reasonable and feasible.It has important theory value and actual guiding significance to study the surrounding rock destroying law and supporting technique of roadway with variable-width coal pillars, and it provides science basis to the roadway deformation control under similar condition.更多还原