【作者】 任仰辉；

【导师】 张文泉；

【作者基本信息】 山东科技大学 ， 采矿工程， 2009， 硕士

【摘要】 肥城矿区下组煤层群包括7煤、8煤、9煤和10煤四个薄煤层,煤层间距较小,隔水层较薄,矿井开采时尤其进入深部开采受五灰和奥灰含水层的威胁严重,极易导致突水灾害。本文以肥城矿区下组煤开采这种多煤层、大采深、高水压、构造复杂等复杂条件为背景,根据弹塑性力学理论和矿山压力理论等学科知识,分析了工作面开采后煤层底板岩层应力及变形规律,建立了垮落法、条带法及充填法开采时工作面围岩破坏区域的力学计算模型,推导了底板应力和破坏深度的计算公式;采用FLAC3D数值模拟软件,对比研究了完整岩层底板条件下和含不同倾角、不同位置、不同落差断层带时底板采动效应特征及采动和水压对底板破坏效应的耦合作用;从管理地压和控制顶底板灾害的角度介绍了采煤方法的分类,通过对四个煤层采用的不同采煤方法进行组合,分为23种方案并建立相应的数值模型,对近距离薄煤层群开采时顶底板在采动影响下的最大主应力和破坏特征进行模拟;通过在煤底板中布置泄水巷道,并对其进行应力应变测试,整理分析围岩的应力、顶底板变形与破坏等宏观矿压显现量,进一步研究了工作面回采过程中底板变形破坏特征及构造活化规律等,并验证了数值计算的结果;在进行承压水对突水作用分析、底板岩层组合及其阻水性能分析的基础上,采用底板突水系数法对下组煤层群开采掘进工作面及回采工作面进行了底板水患威胁分析;结合底板采动效应研究成果及肥城矿区下组煤层群底板隔水层厚度,对深部高承压水薄隔水层煤层群回采工作面进行了开采安全性评价及可选采煤方法的可行性分析;根据上述研究成果,结合矿区水害防治现状,提出复杂条件下煤层群开采底板水害综合防治技术。更多还原

【Abstract】 The sublevel series of coal seams in Feicheng mining area include 7#seam, 8#seam, 9#seam, and 10# seam, within which the space is quite small and the aquifuge thickness is thin, it is quite easy to cause water irruption by mining activities especially in the deep part which is threatened by the fifth-layer limestone and Ordovician limestone. In this paper, based on the sublevel series coal mining with characters of multi-layers, great depth, high hydraulic pressure, complicated structure and so on in Feicheng mining area, according to the elastic-plastic theory and the underground pressure theory, the stress distribution and deformation law of floor terrane after mining is analyzed, the mechanical models of surrounding rock damage area of workface in the condition of caving method, strip mining method and backfilling method are established, and thus to deduce the calculating formula of floor stress and damage depth. Using FLAC3D, mining effect characters of floor and coupling functions of the floor damage caused by mining and water pressure is researched in the condition of complete terrane floor contrasted with various obliquity、various position、various faultage fall. The classification of mining methods is presented according to pressure management and roof and floor hazard control theory, assembling the different mining methods of the four layers, 23 programs are classified and corresponding numerical models are established, to simulate the maximum principle stress and damage characters of the roof and floor affected by mining when short distance thin-layer coal groups are mined. The leaking laneway is arranged in the floor, and the stress and deformation tests are made in the leaking laneway, sorting out and analyzing the macroscopy underground pressure behaviors including the stress of the rock wall, deformation and damage of the roof and floor, then the characters of the coal floor terrane deformation and damage and the structure activation rules during the mining process are studied, and to verify the numerical calculation results. Based on the analysis of the effect of confined water to the water inrush and the classification of the terrane in the floor and their water-resisting ability, using floor water inrush coefficient method, the water inrush possibility analysis is done in the workface and exploring face of the sublevel series coal. Combining the research results of mining effect in the floor and the aquifuge thickness of the sublevel series coal in Feicheng mining area, mining safety analysis and feasibility analysis of eligible mining method are obtained in the deep coal layer with high-water-stress and thin aquifuge thickness. According to the above results, combining with the current situation of water hazard prevention, synthesized floor water hazard prevention technique is put forward when mining the sublevel series coal under complicated conditions.更多还原