断裂带影响范围内煤柱稳定性及突水机理研究

发布时间：2018-05-09 15:29

本文选题：断层 + 防水煤柱　；参考：《北方工业大学》2013年硕士论文

【摘要】：本论文工程背景为平朔煤炭工业公司安家岭二号矿29213工作而,主采煤层为9#煤层,工作面受断层影响断层倾角75。,断层落差约为70m,延伸850米。由于存在较大断距,断层下盘奥陶系含水层上移,接近上盘煤层。当工作面推进时,受采动影响底板可能与断层贯通形成突水通道,严重威胁采场的安全生产。本文通过对安家岭二号井工矿29213工作面受断层影响工作面正常回采的情况下,采用室内试验、理论分析和数值模拟等方法,对沿断层走向工作面开采的矿压显现基本规律及突水情况进行预测和研究。收集矿区地质水文资料,通过室内的岩石渗透性试验,分析隔水层、含水层顶部岩体和断裂带岩石的渗透性和富水性。根据Mohr-Coulomb强度准则、SMP强度准则和Lade强度准则进行防水煤柱的理论分析,分别建立煤柱留设合理宽度的力学公式,确定安全隔水煤柱宽度范围为30-33m,该公式很好地验证了断层影响下工作面的稳定性。在留设一定宽度煤柱的条件下,采用FLAC-3D数值模拟软件,确立煤柱合理宽度为30米,分析应力场和位移场的变化规律,确定煤壁前方塑性破坏区宽度15米,断层活化位置与最大破坏深度还有15米的安全距离,很好的验证了30米煤柱的合理性。建立底板突水破坏的力学模型,当留设30m煤柱时,计算工作面靠近断层侧的底板破坏深度为18m,远小于高峰应力传播线交点与煤层的距离,所以底板裂隙带与断层还有一定距离,不会形成突水通道,与数值模拟分析结果一致。通过薄板模型分析工作面受采动影响下底板隔水层的极限水压力变化规律,通过理论计算可以求的煤层推进至600米,底板的抵抗极限抗水压力的变化规律,数值不断趋近与1.7MPa左右,根据煤炭工业太原设计研宄院的勘测数据,底板隔水层(本溪组底界)承受最大静水压力Pu,为1.329MPa,可见采场安全,为矿区安全生产提供理论依据。
[Abstract]:The engineering background of this paper is 29213 working in Anjialing No. 2 Coal Mine of Pingshuo Coal Industry Company. The main coal seam is 9# coal seam, the face is affected by fault dip angle 75.The fault drop is about 70m, extending 850m. Due to the existence of large fault spacing, the Ordovician aquifer in the lower face of the fault moves up and approaches the upper coal seam. When the face is advancing, the water inrush passage may be formed between the floor and the fault under the influence of mining, which seriously threatens the safe production of the stope. In this paper, under the condition of normal mining under the influence of fault on 29213 face of Anjialing No. 2 well, laboratory test, theoretical analysis and numerical simulation are adopted. The basic law of rock pressure and water inrush in mining face along fault strike are predicted and studied. The geological and hydrological data of the mining area are collected, and the permeability and water enrichment of the rock in the water-isolated layer, the top rock of the aquifer and the rock in the fault zone are analyzed through the laboratory rock permeability test. According to Mohr-Coulomb strength criterion and Lade strength criterion, the theoretical analysis of waterproof coal pillar is carried out, and the mechanical formula of reasonable width of coal pillar is established respectively. The width range of the safe water-insulated coal pillar is determined to be 30-33m.The formula well verifies the stability of the working face under the influence of faults. Under the condition of keeping a certain width of coal pillar, the reasonable width of coal pillar is determined to be 30 meters by using FLAC-3D numerical simulation software. The variation law of stress field and displacement field is analyzed, and the width of plastic failure zone in front of coal wall is determined to be 15 meters. The safety distance between fault activation position and maximum failure depth is 15 meters, which verifies the rationality of 30 meters coal pillar. The mechanical model of water inrush failure of floor is established. When 30m coal pillar is set up, the failure depth of floor near the fault side is calculated to be 18m, which is far less than the distance between the intersection of peak stress propagation line and coal seam, so there is still some distance between the fracture zone of floor and fault. No water inrush is formed, which is consistent with the results of numerical simulation. Based on the thin plate model, the variation law of the limit water pressure of the floor diaphragm under the influence of mining movement is analyzed, and the change law of the ultimate water resistance pressure of the floor can be obtained by the theoretical calculation of the coal seam advancing to 600 meters, and the resistance of the floor to the limit water pressure. According to the survey data of Taiyuan Institute of Design and Research of Coal Industry, the bottom layer (bottom boundary of Benxi formation) bears the maximum hydrostatic pressure Pui, which is 1.329MPa. The safety of stope can be seen, which provides the theoretical basis for the safety of mining area.
【学位授予单位】：北方工业大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TD745

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