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为了确定向斜构造煤与瓦斯突出机理,从应力、煤体结构特征和瓦斯压力及含量等方面对向斜构造进行了分析.利用弹性梁的应力、应变理论,分析了煤层与围岩组成的软硬互层系统的层间滑动特征和应力-应变特征、煤体宏观与微观结构特征、瓦斯压力与瓦斯含量分布特征.研究表明,向斜构造的两翼与轴部中性层以上为高压区,中性层以下为相对低压区,距离向斜轴部越近,主应力及其梯度越大.向斜构造形成过程中的层间滑动造成煤体原生结构遭到破坏,煤体强度降低,煤层增厚.向斜构造部位瓦斯生成量亦相对较高,同时中性层以上煤(岩)体中的裂隙和孔隙被压密、压实而闭合,阻止了下部瓦斯的向上逸散,中性层以下的张性作用下的断裂或折裂面、煤体中的割理、节理等降低了解吸压力,形成良好的瓦斯聚集空间,也有助于煤层中吸附瓦斯的解吸,使得向斜轴部瓦斯含量较高.向斜构造同时具备的高地应力、高瓦斯压力(含量)和构造煤发育等3个因素是其发生煤与瓦斯突出的主要原因. 相似文献
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煤与瓦斯突出机理的探讨 总被引:4,自引:0,他引:4
认为突出危险源是存在于采矿活动中的具备发动煤与瓦斯突出的高势能瓦斯与破碎煤体混合的瓦斯富积区。研究了突出危险源的形成、突出发动的条件,提出了预防煤与瓦斯突出需要重视的几个问题。 相似文献
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瓦斯地质法在煤与瓦斯突出预测中的应用 总被引:1,自引:0,他引:1
介绍了中马村煤矿的基本情况。运用瓦斯学的一般原理,对该矿的瓦斯地质进行分析和整理,建立了适合该矿的煤与瓦斯突出预测瓦斯地质法,通过比较证实了瓦斯地质法比其它预测方法安全经济。 相似文献
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本文对十二矿煤与瓦斯突出的地质因素:地质构造、煤体结构、煤厚及其变化和煤层围岩等进行了分析,剖析了煤与瓦斯突出与上述地质因素之间的密切关系。 相似文献
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采用有机溶剂萃取和煤成烃热模拟实验,对煤层受构造应力作用时的煤结构变化及构造煤的生烃特征进行研究.结果表明:构造煤的正己烷、苯萃取率与原生结构煤基本相近,而氯仿萃取率是原生结构煤的2倍多,构造煤含有很高的氯仿可溶低分子化合物;构造煤分子间的作用力小,决定了构造煤强度低和吸附性能高,从而控制了煤与瓦斯突出灾害的发生;煤的氯仿萃取率可以作为预测煤与瓦斯突出的指标.构造煤生烃潜力小,反映在构造应力作用下,曾经生过烃(瓦斯).在构造应力作用下,煤中的有机质超前向两个方向演化,一方面聚合形成更大的高芳构化的大分子结构,另一方面则形成低分子化合物和气态烃(瓦斯). 相似文献
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以瓦斯地质理论为基础,运用区域构造演化理论,分析了矿区、矿井瓦斯地质规律,调研了大平煤矿“10·20”矿难发生特大型煤与瓦斯突出的地质原因,即新密矿区中三叠世受构造强烈挤压作用,晚侏罗世至早白垩世、晚白垩世至第三纪受构造拉张和重力滑动作用.大平煤矿垂深450 m以浅,以低瓦斯为主;深部瓦斯地质条件复杂,存在着煤与瓦斯突出危险的分区、分带特征,并受地质构造的控制.“10·20”煤与瓦斯突出发生在构造复合部位,应力集中、构造煤发育,是岩石掘进工作面遇一逆断层而引起的. 相似文献
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运用经典气体动力学理论,对突出孔洞内煤-瓦斯两相流的运动参数进行了一维讨论,推导了压力、密度、速度及流量等参数之间的数学函数关系,分析了突出过程中煤-瓦斯两相流流动的临界状态以及与其相关的两相流声速理论,并通过数值模拟和现场实例对临界流动理论进行了直观描述。在煤与瓦斯突出过程中,煤-瓦斯两相流的出口流动状态与孔洞形态、瓦斯压力、煤体破坏速度、瓦斯含量等因素密切相关。当两相流在孔口达到并超过临界状态时,由于突出孔洞口小腔大的形状限制了瓦斯流的完全膨胀,此时喷出的瓦斯流处于未完全膨胀状态。大量未完全膨胀状态的瓦斯流在巷道空间的瞬间膨胀可产生巨大的动力效应,从而严重破坏矿井生产设备和通风设施。临界运动状态是影响煤与瓦斯突出动力效应的关键因素之一,它对煤与瓦斯突出灾害的预警和防护都有重要意义。 相似文献
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Carried on the one-dimensional analysis to the motion state of coal-gas flow in the outburst hole, and deduced the relational expression between the motion parameters (containing of velocity, flow rate and density etc.) of bursting coal-gas flow and gas pressure in the hole, then pointed out the critical state change of coal-gas flow under different pressure conditions which had the very tremendous influence on both stability and destructiveness of the entire coal and gas outburst system. The mathematical processing and results of one-dimensional flow under the perfect condition are simple and explicit in this paper, which has the certain practical significance. 相似文献
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基于灰色系统理论,建立多指标加权灰靶突出可能性决策模型,对矿井煤与瓦斯突出的可能性进行量化评价。根据10组煤与瓦斯突出危险区域测点数据与预测煤层突出危险性单项指标临界值的靶心距的大小,对矿井突出可能性大小进行评价,并进行了突出可能性等级划分。应用该模型对花宝沟煤矿煤与瓦斯突出的可能性进行评价,评价结果是靶心距距离较大,可能性小,不易发生突出,评价结果与实际情况一致。说明应用多指标加权灰靶突出可能性决策模型对矿井进行煤与瓦斯突出危险性评价是可行的。 相似文献
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According to the research results of motion parameters of coal-gas flow, analyzed the formation mechanism of shock waves at
different states of coal-gas flow in the process of coal and gas outburst, and briefly described the two possible cases of
outburst shock wave formation and their formation conditions in the process of coal and gas outburst, and then pointed out
that a high degree of under-expanded coal-gas flow was the main reason for the formation of a highly destructive shock wave.
The research results improved the shock wave theory in coal and gas outburst.
Supported by the Key Program of National Basic Research Program of China (973) (2005CB221504); the Key Program of National
Natural Science Foundation of China (50534080) 相似文献
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Measured to control serious coal-gas outburst in coal seam were analyzed by theory and experimented in test site. A new technique
to distress the coal-bed and drain methane, called hydraulic slotting, was described in detail, and the mechanism of hydraulic
slotting was put forward and analyzed. The characteristic parameter of hydraulic slotting was given in Jiaozuo mining area
and the characteristic of validity, adaptability and security was evaluated. The results show that the stress surrounding
the strata and the gas in coal seam is released efficiently and thoroughly while new techniques are taken, as slotting at
heading face by high pressure large diameter jet. The resistance to coal and gas outbursts is increased dramatically once
the area of slotting is increased to a certain size. In the process of driving 2 000 m tunnel by hydraulic slotting excavation,
coal and gas outburst never occurre. The technique could be used to prevent and control potential coal-gas outburst in the
proceeding of tunnel driving, and the speed tunneling could be as high as more than 2 times.
Supported by National Nature Science Foundation of China(50534070); International Science and Technology Cooperation and Communion
Key Project of Ministry Science and Technology of China (2005DFA61030); Natural Science Foundation of Henan Province (200510460014);
Coal Mine Gas and Fire Prevention and Control Key Laboratory Foundation of Henan Province (HKLGF200708) 相似文献
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构建了煤表面与CH4的吸附模型,采用量子化学密度泛函(DFT)理论计算方法,在B3LYP/6-311G计算水平上,对构建的煤与CH4分子吸附伴生体系结构进行优化,得到了吸附平衡态的几何构型,计算了吸附能和振动频率,从而得出煤与瓦斯突出微观机理:在矿井生产中,由地震、开采等引起采掘工作面围岩应力变化导致煤岩体破裂,煤岩体破裂产生频率范围宽广的电磁波.由量子化学密度泛函理论(DFT)计算得到煤与瓦斯的吸附为物理吸附,吸附能为1.16 kJ/mol.煤与CH4吸附形成的伴生分子体系以量子化形式吸收宽频电磁波,导致该体系由基态变为激发态,使得瓦斯由吸附态脱附变为游离态,形成大量的游离态瓦斯,在弱面发生煤与瓦斯突出. 相似文献