【作者】 谭军；

【导师】 刘盛东；

【作者基本信息】 安徽理工大学 ， 矿业工程， 2006， 硕士

【摘要】 在煤系地层直接覆盖有古老的推覆体是新集矿区特有的地质现象。该推覆体由前寒武系的片麻岩和寒武系的石灰岩组成,资源勘探结果表明,这两种岩性的地层均是富水性不均匀的、具有显著各向异性的含水层。为了防止推覆体含水层中的地下水通过煤层顶板中的采动导水裂隙带进入回采工作面,新集矿区各矿的矿井设计中对各主采煤层针对推覆体均要求留设80—100m的保护煤柱。本课题研究的目的就是以新集二矿1101工作面为例、通过分析工作面的充水条件、推覆体含水层的分布规律以及采动导水裂隙带的发育高度来确定缩小防水煤柱的可行性。 新集二矿1101工作面位于水平中央采区11-2煤西翼。该工作面顶板距推覆体的垂向距离为17.5—75.8m。根据新集二矿对8煤和11—2煤的开采经验,只要回采的工作面上覆的外来地层不是强含水层或煤层的顶板岩体得不到外来系统中强含水层的补给,适当地缩小防水煤岩柱将不会影响工作面的安全回采。 本次研究在收集大量现有资料和进行大量室内、原位试验的基础上,采用工作面涌水量动念分析和对比的方法分析了工作面的充水条件、应用地质统计学中的非线性分析法预测了推覆体及其中灰岩含水层的分布以及采用三维数值模拟法计算了工作面顼板中采动导水裂隙带的最大发育高度。研究结果表明,在采取适当的排水措施后安全开采1101工作面是完全可行的。更多还原

【Abstract】 Xinji Mine Field is geologically characterized by the occurrence that the coal-bearing formations lie directly under tow thrust sheets consisting of gneiss from Antecambrian and limestone from Cambrian respectively. The coal resource exploration carried out in this mine field resulted in a prediction that these thrust sheets should have such hydraulic characters as heterogeneous and anisotropic aquifers. In order to avoid that the groundwater stored in the thrust sheets seepages through the fractures induced in the roof strata by mining into the working panel, a coal belt with a width of 80—100m from all major coal seams was designed as protection pillar. The aims of the present work are, based on analyzing the recharging conditions of extracted panels, the distribution of the hydrogeological parameters of the thrust sheets and the maximum height of mining induced fractures in the roof of the coal seam to extract, to take the working panel 1101 of Xinji Second Mine as an example and investigate the workability to mine a part of the coal in the designed protection pillars.The working panel 1101 is designed to mine the coal seam 11-2 and located at the western part of middle mining field of Xinji Second Mine. The vertical distance between the roof and the lowest thrust sheet varies from 17.5m to 75.8m. Experiences obtained while mining coal seam 8 and coal seam 11-2 suggests it brings no negative influences upon the mining activity to scale down the designed pillar size if the stratum overlying on the roof of the panel to be mined is not strong permeable aquifer or the fractured roof strata of the panel can not be directly recharged by a strong permeable aquifer within the thrust block.On the basis of performing amount of laboratory experiments and in situ tests and summarizing documents accumulated in geological exploration phase and former mining, the spatial distribution of thrust sheets, the recharging conditions of the mined panels driven into coal seam 11 -2 and the maximum height of the mining induced fractures in roof strata were analyzed or calculated by using geostatistic nonlinear methodology, dynamic flow rate progression and three-dimensional numerical simulation respectively. The conclusion resulted from present research is it would be guaranteed to extract safely the working panel 1101 when proper dewatering measures are implemented.更多还原