利民煤矿煤与瓦斯突出的地质构造条件研究

在对湖南利民煤矿煤与瓦斯弱突出区域、强突出区域和未突出区域的地质构造特征作详细分析后,发现煤层顶底板断-褶构造发育不协调、边界条件不一样,引起Ⅰ、Ⅱ、Ⅲ、Ⅳ各区的应力分布不均匀,构造复杂程度具一定的差异性;同时探讨了构造应力场和煤与瓦斯突出的关系,认为构造应力决定着突出强度的大小,进而控制煤与瓦斯突出的区域、密度、强度的差异性.所得结论为矿区煤与瓦斯突出预测防治提供了理论依据.     

利民煤矿煤与瓦斯突出的地质构造条件研究

在对湖南利民煤矿煤与瓦斯弱突出区域、强突出区域和未突出区域的地质构造特征作详细分析后 ,发现煤层顶底板断 褶构造发育不协调、边界条件不一样 ,引起Ⅰ、Ⅱ、Ⅲ、Ⅳ各区的应力分布不均匀 ,构造复杂程度具一定的差异性 ;同时探讨了构造应力场和煤与瓦斯突出的关系 ,认为构造应力决定着突出强度的大小 ,进而控制煤与瓦斯突出的区域、密度、强度的差异性 .所得结论为矿区煤与瓦斯突出预测防治提供了理论依据 .     

构造煤的研究现状与发展趋势

构造煤是煤矿瓦斯灾害防治和煤层气开发的重要研究内容之一.通过分析,论述了构造煤分类、成因、物理力学性质及其对瓦斯突出控制4个方面的历史成果,提出了构造煤研究中存在的问题和今后研究的方向,指出进一步深化成因研究是构造煤研究的基础,通过开展区域构造控制下不同成因、不同类型构造及构造群落对构造煤形成的控制作用,建立构造煤的控制模式,是今后构造煤研究的核心.     

淮南矿区井田小构造对煤与瓦斯突出的控制作用

井田小构造要素是控制煤与瓦斯突出的主要地质因素,它综合影响其他因素,会造成不同破坏程度的煤体结构.对淮南矿区煤与瓦斯突出点构造资料的统计表明,突出点受构造控制的占近64%,而煤、岩巷中的构造控制突出占近72%,突出点由小断层引起煤层产状及煤体结构强烈揉皱的占100%.淮南矿区煤与瓦斯突出点的构造组合形式分断层构造、断层与褶皱叠加和褶皱构造三类,其中断层组合又分地堑型、阶梯型、断层交汇型、挤压构造型和顺层断层型五种.小构造发育是造成煤与瓦斯突出平面分区性和空间分带性的主要原因,构造煤发育程度是造成煤与瓦斯突出发生的直接原因;必须进一步加强小构造对构造煤发育控制范围的研究,提高煤与瓦斯突出预测预报地质构造指标的可靠性.     

淮南矿区井田小构造对煤与瓦斯突出的控制作用

井田小构造要素是控制煤与瓦斯突出的主要地质因素,它综合影响其他因素,会造成不同破坏程度的煤体结构.对淮南矿区煤与瓦斯突出点构造资料的统计表明,突出点受构造控制的占近64%,而煤、岩巷中的构造控制突出占近72%,突出点由小断层引起煤层产状及煤体结构强烈揉皱的占100%.淮南矿区煤与瓦斯突出点的构造组合形式分断层构造、断层与褶皱叠加和褶皱构造三类,其中断层组合又分地堑型、阶梯型、断层交汇型、挤压构造型和顺层断层型五种.小构造发育是造成煤与瓦斯突出平面分区性和空间分带性的主要原因,构造煤发育程度是造成煤与瓦斯突出发生的直接原因;必须进一步加强小构造对构造煤发育控制范围的研究,提高煤与瓦斯突出预测预报地质构造指标的可靠性.     

地质构造对煤与瓦斯突出控制作用的研究现状与发展趋势

初步分析了各类地质构造对煤与瓦斯突出的控制作用,对各类构造带发生的典型突出实例做了统计.地质构造对煤与瓦斯突出控制作用的研究,一百多年来多是定性的分析和统计研究,而定量化的研究还处在初步尝试阶段.指出在定性研究成果的基础上,指导开展对地质构造控制煤与瓦斯突出发生作用机理的定量化研究,深入分析构造应力场、煤岩破裂场和瓦斯运移场耦合演化动力学规律是该研究方向的发展趋势.     

祁东矿煤与瓦斯突出动力成因分析

针对祁东矿多发生小型突出且地点多在构造应力区的现状,采用划分地质单元方法评价其煤与瓦斯突出危险性。结果表明:4个地质单元瓦斯赋存条件和主控因素不同,25次突出集中发生的第Ⅱ单元,主控因素为地应力;测试了原岩地应力场特征,发生多次突出的中央回风下山巷道走向为近SN向,与最大主应力方向夹角大,掘进过程中煤体承受应力较大,构造煤发育;对比同一埋深其它已揭露煤层区域,在瓦斯含量相差不大的情况下,动力现象差异很大;这些都证实瓦斯不是突出的主要动力来源,突出主要动力来源为构造应力,这也决定了不会发生大型煤与瓦斯突出,对瓦斯预测和防治有重要指导意义。     

新安煤田煤与瓦斯突出特征及控制因素分析

为了掌握煤与瓦斯突出的特征和控制因素,提高煤矿防突工作的针对性,本文通过统计分析了新安煤田内义煤集团的4个煤与瓦斯突出矿井近年来发生的瓦斯动力现象,综合分析得出新安煤田煤与瓦斯突出具有以小型突出为主、突出前有预兆并受作业方式诱导、突出点附近瓦斯质量体积和瓦斯压力高、易发生在掘进工作面和煤层变化带的特征;分析总结了埋藏深度、瓦斯赋存、地质构造、煤层厚度变化、构造软煤、作业工艺是控制新安煤田煤与瓦斯突出的主要因素,为该煤田防治煤与瓦斯突出提供了理论指导.     

新安煤田煤与瓦斯突出特征及控制因素分析

为了掌握煤与瓦斯突出的特征和控制因素,提高煤矿防突工作的针对性,本文通过统计分析了新安煤田内义煤集团的4个煤与瓦斯突出矿井近年来发生的瓦斯动力现象,综合分析得出新安煤田煤与瓦斯突出具有以小型突出为主、突出前有预兆并受作业方式诱导、突出点附近瓦斯质量体积和瓦斯压力高、易发生在掘进工作面和煤层变化带的特征;分析总结了埋藏深度、瓦斯赋存、地质构造、煤层厚度变化、构造软煤、作业工艺是控制新安煤田煤与瓦斯突出的主要因素,为该煤田防治煤与瓦斯突出提供了理论指导.     

综采放顶煤与瓦斯突出的耦合关系研究

对煤与瓦斯突出发生的综合作用机理及治理技术进行总结,从宏观上提出治理煤与瓦斯突出的技术手段;分析总结我国综采放顶煤开采的技术成果,讨论了工作面应力分布规律和顶煤变形规律对突出的影响;认为:具突出危险性的厚煤层采用综采放顶煤开采法对消突是有积极作用的.     

Coal and gas outburst mechanism of the "Three Soft" coal seam in western Henan

Based on the particularities of gas outbursts,i.e.,low gas beating capacity and low gas pressure in the"Three Soft"coal seam in western Henan,we applied the theories of plate tectonics and regional structural evolution to investigate the mechanism of this seam and its impact on the coal seam gas formation.Our investigation revealed that coal and gas outbursts are distributed in a strip in a NW direction,with a number of high-penetration mines scattered towards the south side and low-gas mines largely located on the north side.We analyzed the statistics of 38 gas explosions and the rock-coal sturdiness number coefficient f of 167sampling sites in the region and found the gas outburst mechanism that features a"low indicator outburst phenomenon".The mechanism is characterized by structural coal as its core,a low gas bearing capacity,low gas pressure and sturdiness coefficient f mostly less than 0.3.Our research results provide a theoretical foundation for effective control of gas disasters.     

Effect of protective coal seam mining and gas extraction on gas transport in a coal seam

A gas–solid coupling model involving coal seam deformation,gas diffusion and seepage,gas adsorption and desorption was built to study the gas transport rule under the effect of protective coal seam mining.The research results indicate:(1) The depressurization effect changes the stress state of an overlying coal seam and causes its permeability to increase,thus gas in the protected coal seam will be desorbed and transported under the effect of a gas pressure gradient,which will cause a decrease in gas pressure.(2) Gas pressure can be further decreased by setting out gas extraction boreholes in the overlying coal seam,which can effectively reduce the coal and gas outburst risk.The research is of important engineering significance for studying the gas transport rule in protected coal seam and providing important reference for controlling coal and gas outbursts in deep mining in China.     

煤与瓦斯突出的压力容器物理爆炸假说

根据掘进工作面前方支承压力分布特征,建立了掘进工作面前方煤体的压力容器模型．通过分析认为,该模型满足压力容器爆炸的2个条件：气体迅速膨胀和容器壁脆性断裂．进而,基于压力容器发生物理爆炸前的孕育、爆炸后的能量及破坏能力,解释了煤与瓦斯突出的预兆、基本特点和一般规律,并分析了石门自行突出等问题的原因．最后,基于压力容器物理爆炸条件,给出了煤与瓦斯突出的预测指标和防突施工的努力方向,并对已有防突措施进行分析和评价．煤与瓦斯突出的压力容器物理爆炸假说的提出,对揭示煤与瓦斯突出机理具有重要意义．     

两软一硬煤层突出控制因素与发生规律

针对两软一硬煤层特殊的瓦斯地质条件,以云盖山井田一矿二1煤层为例,探寻了两软一硬煤层煤与瓦斯突出的控制因素,分析了掘进工作面掘进期间突出预测指标的分布特征,总结归纳了"两软一硬"煤层煤与瓦斯突出发生规律.研究结果表明,由于地质构造变动,云盖山一矿二1煤层产状变化较大,煤层倾角发生急剧变化的地带,地应力集中;受层间滑动构造的影响,煤层厚度变化较大,具有突然增厚、变薄以至尖灭、挤灭现象;二1煤层构造软煤呈连续层状发育.因此,在煤层薄、厚交接处(煤层急剧变化带),小断层附近,应力集中,瓦斯积聚,煤体破坏严重,易发生突出.此项研究,可为地质条件类似矿井开展瓦斯地质研究和瓦斯灾害防治工作提供方法借鉴和理论指导.     

演马庄煤矿突出煤层炮采放顶煤工作面防治煤与瓦斯突出的方法和措施

介绍了演马庄煤矿 2 70 2工作面突出煤层炮采放顶煤效果检验的方法和防止煤与瓦斯突出所采取的措施 ,提出突出煤层炮采放顶煤工作面瓦斯抽放是防止煤与瓦斯突出的有效手段 ,当工作面有煤与瓦斯突出危险时 ,采取恰当的防突措施 ,能够降低煤与瓦斯突出的危险程度 ,可供同类工作面回采时借鉴     

Failure modes of coal containing gas and mechanism of gas outbursts

In order to explain the mechanism for gas outburst, the process of evolving fractures in coal seams is described using system dynamics with variable boundaries. We discuss the failure modes of coal containing gas and then established the flow rules after failure. The condition under which states of deformation convert is presented and the manner in which these convert is proposed. In the end, the process of gas outbursts is explained in detail. It shows that a gas outburst is a process in which the boundaries of coal seams are variable because of coal failure. If the fractures are not connected or even closed owing to coal/rock stress, fractured zones will retain a certain level of carrying capacity because of the self-sealing gas pressure. When the accumulation of gas energy reaches its limit, coal seams will become unstable and gas outbursts take place.     

Research on Geological Structure Mark of Coal and Gas Outbursts in Pingdingshan Mining Area

Based on the study of regional displaying rules of coal and gas outburst controlled by geological structure in Pingdingshan mining area, the geological structure features in outburst sites were investigated emphatically. The combination type, orientation and least seam thickness in outburst sites were put forward. This research provides a geological mark for forecasting gas outbursts in deep mining.     

Geophysical criterion of pre-outburst coal outsqueezing from the face space into the working

The initial process of coal and gas sudden outburst is studied in the article when under the influence of rock and gas pressure the part of a coal seam layer(a coal section) is squeezed out from the mouth of the future outburst cavity in a jump-like manner into the working. Geo-mechanical criterion for a part of a coal seam layer outsqueezing in the form of the relation of active(squeezing out) and passive(preventing the outsqueezing) forces is defined in the article. Based on it, the geophysical criterion is defined by expressing basic physical parameters through geo-physical ones: the current stress is defined by spectral-acoustic method through the ratio of high frequency and low-frequency components of an acoustic signal, which is generated into a face working space by the mining equipment operating in the face; in-situ gas pressure is defined by gas analytical method by the concentration of methane in the atmosphere of the working; the strength of the most broken coal layer is defined by a strength measuring device(a device for measuring the depth of a steal cone punched into the coal by a spring mechanism). This paper studies the influence of acoustic, strength and filtrating and collecting properties of a face working space on the limit value of an obtained geophysical criterion of pre-outburst squeezing of a coal ‘‘plug" out of the mouth of the future outburst cavity into the working.