【作者】 张乐中；

【导师】 赵法锁； 肖平新；

【作者基本信息】 长安大学 ， 地质工程， 2013， 博士

【摘要】 水源条件和导水通道是矿井突水的基本条件。对于底板岩溶突水来讲，水源条件应该是对岩溶含水层的特征进行研究，而导水通道则应该是对底板隔水层结构的研究。通过研究底板隔水层受采动破坏的规律，对人们认识底板突水机理及有效预防突水事故的发生十分重要。本文以高承压岩溶水下煤层的开采为背景，具体以王峰井田下组煤的开采为研究对象，围绕底板隔水层由于采动破坏诱发突水而展开研究。首先，通过分析大量突水资料，归纳总结出底板突水六大影响因素：含水层的富水性、含水层水头压力、底板岩层岩性及其组合特征、地质构造、矿山压力及开采方法等；岩石的全应力－应变－渗透规律表明岩石的渗透特性与岩石的岩性和围压密切相关，裂隙和孔隙变化引发岩石渗透率发生变化，因此对水岩相互作用进行了研究；针对王峰井田内奥灰岩含水层的水文地质及工程地质特征，提出王峰井田底板突水的两类基本类型，即完整型底板突水和断层型底板突水。在下三带理论的基础上，结合水岩相互作用的机制，对底板突水的机理进行了研究。其次，对深部岩溶含水层的特征进行了研究，认为其在平面上和垂向上的分布并不均匀，深部岩溶渗透性及富水性规律都随着埋深的加大而减弱；并对井田岩溶发育情况进行了研究，认为井田内的奥陶系石灰岩是由相对隔水层段与几个含水层段复合而成的，上马家沟组二段富水性最强且离煤系最近，故其是开采11#煤层时的充水水源。第三，通过对奥陶系灰岩顶部风化带成因进行的研究，认为风化壳岩溶充填带在全华北煤田普遍存在，处于风化壳带上的岩溶不发育，具有良好的阻水性能。对研究区峰峰组顶部岩溶发育进行了着重研究，采用收集前人资料、野外实地调查、水文地质勘探、室内外相关试验及测试等手段对峰峰组的隔水性进行了验证，认为在研究区内峰峰组顶部存在厚度为40m左右的隔水层。最后，采用数值模模拟手段，对11#煤层的开采进行了不同孔隙水压力、不同隔水层厚度状况下模拟计算。揭示了深部底板隔水层在采动影响下的采动破坏规律。结果显示，底板岩层的破裂深度和破裂范围不因隔水层厚度的变化而发生明显的变化，塑性破坏深度的最大值均为22.5m。同时，采用三种不同方法对王峰井田11#煤层底板开采的安全性进行了初步评价，认为11#煤在底板无断裂的情况下开采是可行的。本文的研究成果对王峰井田在高承压水上安全开采11#煤具有重要的理论意义和实践价值。其结果对于其它煤田的开采也具有一定的参考价值。更多还原

【Abstract】 The water supply and water drain channel is a general conditions for water bursting inmine. For the water inrush in the karst floor, the characteristic of the karst aquifer is theimportant factor for the studies of the water supply. For the water drain channel, the structureof the water-resisting layer in karst floor must be investigated. The mechanism of the waterinrush in the karst floor is very important for the prevention of water inrush accident. Basedon Wangfeng mine Tianxia group and the coal bed exploitation under the high pressureaquifer, water inrush induced by the water-resisting layer exploitation in karst floor is studiedin this paper.Firstly, six influence factor is obtained by the analyses of water inrush data, e.g., thewatery of aquifer, water head pressure and lithology of the rock layer, geological structure,pressure of surrounding rock and exploitation method. The stress-strain and seep flowrelationships of rock is interrelated with the lithology and the confining pressure. Thepermeability of rock is varied with the crack and the porosity. Based on the hydrogeololgyand engineering geology characteristic of the aquifer of Wangfeng mine Tianxia group, twofundamental types of water inrush for Wangfeng mine Tianxia group is proposed, e.g., waterinrush in the perfect karst floor and water inrush in the perfect karst floor. Based on the threezone theory, the mechanism of the water inrush in the karst floor is studied with the boundwater and rock interaction. A criterion for water inrush determination is proposed in thispaper.Secondly, the characteristics of the deep karst aquifer is studied. The karst aquifer isinhomogeneous distributed in plane and vertical directions. The permeability and the wateryof deep karst is decreased with the depth increased. The Ordovician limestone is compoundedby several aquifer, the second segment of the upper Majiagou group have the most watery andclosed to the coal.Thirdly, the top of weathered Ordovician limestone is widely distributed in Huabeicoalfield. However, the rock pack of karst in weathering crust is agensis, and have goodcharacteristics of water resistance. The development and water-resisting property of the karstlocated in the upper Fengfeng group is investigated. The water-resisting layer in the upperFengfeng group is about40m.Finally, the exploitation of11th coal layer is analyzed by numerical simulation with different values of pore-pressure and thickness of water-resisting layer. The failuremechanism of water-resisting layer in deep karst floor is obtained in this paper. The crackingdepth and cracking range of rock in karst floor is irrelevance with the thickness ofwater-resisting layer, and the maximum depth of plastic area is about22.5m. Three methods isused for the stability of the karst floor for11th coal layer evaluation, and11th coal layer issafe for exploitation if the bottom without fault.The results of this paper is as a reference for coal exploitation in11th coal layer underhigh pressure aquifer, and also suitable for other coal mine exploitation.更多还原