大采高综采采场直接顶关键层破断结构特征与稳定性研究

发布时间：2018-01-08 15:40

本文关键词：大采高综采采场直接顶关键层破断结构特征与稳定性研究　出处：《中国矿业大学》2016年硕士论文　论文类型：学位论文

【摘要】：大采高综采采场采高大,覆岩破坏高度大,顶板可能存在直接顶关键层,而直接顶关键层的存在对大采高工作面覆岩运动规律、采场位移应力分布、直接顶关键块稳定性、工作面支架工作阻力及矿山压力显现产生何种影响研究较少。故本文主要结合寺家庄矿15104大采高直接顶关键层综采工作面开采条件,运用理论分析、数值模拟、现场实践等研究方法,对大采高综采采场直接顶关键层破断结构特征与稳定性进行研究,主要得到以下研究成果:(1)研究了大采高直接顶关键层位置判别方法及周期破断形式。根据直接顶关键层工作面上覆岩层不同垮落形态划分为不规整垮落带、规则垮落带、裂隙带和弯曲下沉带“四带”,并给出了直接顶关键层位置判别方法及直接顶关键块以“砌体梁”和“悬臂梁”两种周期破断形式的理论判别式。(2)建立了大采高有无直接顶关键层数值计算模型,研究有无直接顶关键层上覆岩层运动规律、采场应力位移规律以及直接顶关键层层位、块度和硬度对工作面超前支承压力分布的影响规律。(3)建立了直接顶关键块初次破断力学模型,给出了直接顶关键块初次破断滑落失稳和回转失稳的理论判别式;根据直接顶关键块“悬臂梁”周期破断回转过程中能否触及已破断块体形成暂时稳定结构,建立了两种不同运动形式的计算模型,给出了回转过程中能触及已断块体的滑落失稳和回转失稳的理论判别式及回转过程中不能触及已断块体的滑落失稳理论判别式;分析了直接顶关键层和老顶关键层复合破断的影响因素,及出现工作面大小周期来压显现的原因。(4)建立了下位直接顶关键层“悬臂梁”-老顶“砌体梁”结构滑落失稳和回转失稳的计算模型,给出了滑落失稳和回转失稳产生冲击载荷时支架合理工作阻力的计算公式,并分析了工作阻力与各影响因素的关系;建立了上位直接顶关键层“砌体梁”-老顶“砌体梁”结构计算模型,给出了支架合理工作阻力的计算公式。(5)实测得到寺家庄15104直接顶关键层工作面初次来压步距37m,周期来压步距17m,工作面周期来压步距大致相等,不存在大小周期来压,且工作面周期来压持续长度平均达到4.1m,持续时间较长,证实了15104工作面直接顶关键层位于直接顶下部且以“悬臂梁”形式周期性破断。
[Abstract]:Large stope mining high cut in fully mechanized coal mining, overburden failure height of roof, there may be direct roof key stratum, and the existence of direct roof key stratum mining overlying strata movement of high stope, the displacement and stress distribution, the key block stability of immediate roof, show working surface support working resistance and mine pressure Study on the influence of any less. Therefore, this paper combined with Sijiazhuang coal mine 15104 fully mechanized mining high key layer of direct roof surface mining conditions, the use of theoretical analysis, numerical simulation, field practice and other research methods, on the stope of key layer of direct roof breaking fault structure characteristics and stability of large mining height fully mechanized face, the following are the main research results: (1) on the key layer of direct roof position detection method and cycle breaking form of large mining. According to the direct roof key layer of overlying strata of different caving forms into irregular caving zone, the rules of the caving zone, Zone and bending zone of "four zones" crack, and gives the key layer of direct roof position identification method and the direct roof key block "masonry beam" and "beam" two cycle breaking form theory discriminant. (2) established a large mining height has no direct roof key stratum numerical calculation model there is no direct type, on top of key layer of overlying strata movement, stope stress and displacement of key direct overlying layer, fragmentation and hardness of the face ahead of the impact pressure distribution rule of abutment. (3) established the direct roof key block first breaking mechanics model, gives the direct roof key block the first breaking of sliding instability and rotary instability theory discriminant; according to the direct roof key block "beam" cycle breaking in the rotary process can touch the broken block formed a temporary stable structure, the establishment of two different forms of motion model, give back In the rotation process can involve faulted blocks sliding instability and rotary instability theory discriminant and turning process of touch has been broken block sliding instability theory of discriminant analysis of the direct impact of the key; the top layer and the old roof key stratum compound breakage factors and reasons of working face size cycle to pressure. (4) established the direct roof key stratum "cantilever beam" - roof masonry beam structure sliding instability and rotary instability calculation model, given sliding instability and rotary loss calculation formula of steady impact load when the reasonable working resistance of support, and analyzes the working resistance the influence of different factors; set up the key layer of direct roof masonry beam - roof masonry beam structure calculation model, the calculation formula is given the reasonable working resistance of support. (5) obtained Sijiazhuang 15104 key layer of direct roof working face first Time pressure to step away from the 37m, the periodic weighting step distance 17m, face the periodic weighting step distance is approximately equal, the size of the cycle pressure does not exist, and the working face of the periodic weighting length average reached 4.1m, lasted for a long time, confirmed the 15104 work face top key layer is located in the lower part of the top and the cantilever directly "in the form of periodic beam breaking.

【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TD823.97

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