深孔控制卸压爆破及其防突作用机理的实验研究

本文应用相似理论，爆破力学，岩体力学等知识，探讨了深孔控制卸压爆破及其防突作用机理，并进行了实验室的模拟试验：得出了爆破后煤体周围应力分布状态及其孔洞分布形式，研究工作表明：深孔控制卸压爆破能够防止煤和瓦斯突出的主要原因在于采取措施后能够形成较大范围的卸压区，卸压区的形成是防突措施有效性的必要条件。     

煤巷卸压带对煤和瓦斯突出的作用机理

应用岩石力学、弹塑性力学等有关知识，探讨了煤巷卸压区对煤和瓦斯突出发生的作用机理，建立了煤层界面的应力分布状态方程以及煤巷卸压带和地应力、瓦斯压力、煤强度之间的关系式，分析了煤苍卸压区中煤体稳定性的条件，表明：煤和瓦斯突出与工作面前方卸压区的大小有关，突出危险性预测就是检测卸压区的大小，现行防突措施的有效性取决于采取措施后卸压区的长度是否足以防止突出的发生。     

电磁辐射法预测煤与瓦斯突出原理

研究了瓦斯对电磁辐射（ＥＭＥ）的影响规律及影响机制,对电磁辐射法预测煤与瓦斯突出原理进行了探讨,研究结果表明：煤体变形破裂时,电磁辐射与煤岩体的载荷及变形破裂过程密切相关,煤体中的瓦斯能使电磁辐射增强,瓦斯在煤体中的流动及冲击能产生电磁辐射;电磁辐射强度和脉冲数两项指标综合反映了工作面丧方煤体的突出危险程度,用电磁辐射法预测预报煤与瓦斯突出是可行的,煤岩电磁辐射技术在预测煤与瓦斯突出和冲击地压等方     

水力冲孔措施在深部低透气性煤层中的应用研究

针对鹤壁八矿无保护层可采、低透气性突出煤层的现状,采用水力冲孔增透措施,利用数值模拟软件对出煤量与卸压范围大小及卸压范围内煤体位移量的变化情况进行仿真.结果表明,在水射流有效靶距范围内,水力冲孔孔洞半径与卸压范围成正比关系;随着冲孔半径的增大,钻孔周围煤体位移逐渐增大.在应力和瓦斯压力的作用下,孔洞周围煤体发生位移,应力向深部转移.通过检测卸压区内的煤层瓦斯含量与压力,得出卸压范围内煤层瓦斯含量和压力大幅度降低,均降至临界值以下,与数值模拟结果基本相符,说明数值模拟结果是可信的.     

煤巷卸压带及其在煤和瓦斯突出危险性预测中的应用

本文应用岩体力学,弹塑性力学等有关知识,探讨了煤巷卸压带对煤和瓦斯突出的作用机理,建立了煤层界面的应力分布状态方程以及煤巷卸压带和地应力,瓦斯压力,煤强度之间的关系式,并分析了煤巷卸压带中煤体稳定性的条件。研究工作表明:煤巷卸压带中的瓦斯压力,煤体透气性值可以作为突出危险性预测指标和防突措施效果检验的敏感指标。最后,利用自行设计的泡沫封孔测压仪对现场进行了突出危险性预测和防突措施效果检验,得到了十分满意的结果。     

预抽瓦斯防治煤与瓦斯突出的应用实例

安阳龙山煤矿11081区域二1煤层为一突出煤层,本煤层瓦斯预抽是区域性防治煤与瓦斯突出的措施之一.根据预抽煤层瓦斯防突作用原理,选取合理的瓦斯防突有效性指标及各钻孔参数,达到消除该煤层煤与瓦斯突出危险性的目标.据对本煤层瓦斯预抽效果的考查,已达到《防治煤与瓦斯突出细则》之规定,该区域可按无突出危险煤层进行管理.     

预抽瓦斯防治煤与瓦斯突出的应用实例

安阳龙山煤矿11081区域二1煤层为一突出煤层,本煤层瓦斯预抽是区域性防治煤与瓦斯突出的措施之一．根据预抽煤层瓦斯防突作用原理,选取合理的瓦斯防突有效性指标及各钻孔参数,达到消除该煤层煤与瓦斯突出危险性的目标．据对本煤层瓦斯预抽效果的考查,已达到《防治煤与瓦斯突出细则》之规定,该区域可按无突出危险煤层进行管理．     

深水平强突出煤层石门揭煤技术的探讨

采用水力压冲技术,在区域防突措施钻孔施工前先对原始煤体进行水力掏穴,冲出大量煤体和瓦斯,对原始煤体进行卸压增透,以增加煤层的透气性系数,再对卸压后的煤体施工区域防突措施钻孔。将此技术应用在新庄孜煤矿-812 m南边界石门揭B11b煤层中,使得B11b煤层原始瓦斯压力由2.8 MPa降到1.2 MPa,原始瓦斯含量由12.31 m~3/t降到8.5 m~3/t,煤层透气性系数由原来的0.004 83 m~2/(MPa~2·d)增加到0.683 1 m~2/(MPa2·d),水力压冲共计冲出煤粉量285 t,区域措施钻孔瓦斯抽采浓度达35%,瓦斯抽采总量135 316.8 m~3,抽采率63.9%,既缩短了揭煤工期,又保证了揭煤施工过程中的安全。     

突出煤层水力掏槽防突技术措施的应用

以煤巷掘进工作面水力掏槽措施试验为重点，以有效保证掘进施工安全、提高突出地区煤巷掘进速度为目的，通过在焦作煤业集团突出煤层煤巷掘进中的防突实践，确定了合理的水力掏槽措施参数；采用瓦斯涌出及煤体位移考察的手段，对水力掏槽措施的作用机理进行了浅要分析、试验证明，水力掏槽措施卸压范围广、防突效果显著，同时水力掏槽掘进工艺实现了措施期间无人值守，提高了措施、掘进过程的安全性．该技术经现场应用取得了十分显著的效果，具有广泛的适应性、有效性和安全性特征，经济和社会效益显著．     

预抽瓦斯防止煤与瓦斯突出机理及其应用

本文根据在突出煤层中预抽瓦斯所出现的参数变化,初步论证了预抽瓦斯防止煤与瓦斯突出的机理和卸压作用及其变化规律。通过生产现场试验,证明了预抽瓦斯可以大面积防止煤与瓦斯突出。为无解放层的突出矿井开采,提供了新的区域性防止煤与瓦斯突出的技术途径。     

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.     

掘进工作面前方电磁辐射分布规律研究

为了研究煤矿掘进工作面前方煤体内不同深度的煤岩电磁辐射分布规律，利用KBD5电磁辐射监测仪对工作面前方煤体电磁辐射进行了现场测试，基于煤岩电磁辐射力电耦合规律，对煤岩变形破裂过程与电磁辐射强度的相关性进行了理论分析．结果表明：电磁辐射变化与煤体应力状态有较好的对应关系，工作面煤体内部具有多种应力状态和变形破裂状态．文中给出了比较典型的4种电磁辐射分布类型：煤体长期暴露的电磁辐射分布、防突措施后电磁辐射分布、新揭露煤体电磁辐射分布、有构造煤层的电磁辐射分布．     

煤与瓦斯延期突出的突变理论研究

突变理论能比较有效地解决光滑系统中可能出现的突变问题.本文利用突变理论对煤与瓦斯延期突出进行了研究,认为延期突出的滞后时间是由地应力、煤体中的瓦斯、煤的物理力学特性及外作用(爆破等)等的共同作用所产生的,并依此提出了延期突出的预测预报方法.     

Response characteristics of gas pressure under simultaneous static and dynamic load: Implication for coal and gas outburst mechanism

Coal and gas outbursts are dynamic disasters in which a large mass of gas and coal suddenly emerges in a mining space within a split second. The interaction between the gas pressure and stress environment is one of the key factors that induce coal and gas outbursts. In this study, first, the coupling relationship between the gas pressure in the coal body ahead of the working face and the dynamic load was investigated using experimental observations, numerical simulations, and mine-site investigations. It was observed that the impact rate of the dynamic load on the gas-bearing coal can significantly change the gas pressure. The faster the impact rate, the speedier the increase in gas pressure. Moreover, the gas pressure rise was faster closer to the impact interface. Subsequently, based on engineering background, we proposed three models of stress and gas pressure distribution in the coal body ahead of the working face: static load, stress disturbance, and dynamic load conditions. Finally, the gas pressure distribution and outburst mechanism were investigated. The high concentration of gas pressure appearing at the coal body ahead of the working face was caused by the dynamic load. The gas pressure first increased gradually to a peak value and then decreased with increasing distance from the working face. The increase in gas pressure plays a major role in outburst initiation by resulting in the ability to more easily reach the critical points needed for outburst initiation. Moreover, the stronger the dynamic load, the greater the outburst initiation risk. The results of this study provide practical guidance for the early warning and prevention of coal and gas outbursts.     

构造煤及其对煤与瓦斯突出的控制作用

高空隙率、低透气性使构造煤能够保持较高的瓦斯压力 ;破碎性、“隔离”作用及“气垫”作用 ,使构造煤抵御外力作用的能力大大降低 ;构造煤变形幅度大的特性 ,为瓦斯的迅速解吸、放散和快速流动创造了条件 ;构造煤薄弱分层或“通道层”的存在 ,则为煤与瓦斯突出的初始激发和持续发展奠定了基础 ;上述因素的共同作用 ,影响和制约了煤与瓦斯突出的强度和分布 .尽管如此 ,一定厚度的构造煤的存在只是发生煤与瓦斯突出的必要条件和有利条件 ,而非充分条件 .     

煤与瓦斯突出阵面的推进过程及力学条件分析

本文用数学解析方法解出了石门揭煤条件下工作面前方含瓦斯煤体内的稳态应力场和动态应力场。对突出阵面推进过程中任一煤体质点所经历的不同阶段内起主要作用的因素进行了研究，结合煤样的破裂特性用断裂力学的方法分析了突出的发生与发展过程，提出了煤与瓦斯突出机理的球壳失稳假说并给出了突出发生的力学条件。并在突出模拟试验中进行了初步的验证。     

煤的电导率随地应力变化关系的研究

从理论上对煤的导电性及其影响因素进行分析,研究得出了煤的电导率随地应力变化的函数关系;在实验室利用专门研制的实验装置通过测定不同煤在承受不同的应力时的电导率值,得出了煤的电导率与地应力之间的变化关系.实验与理论研究的结果相吻合,从而为利用电磁波透视法预测煤层突出危险性技术的研究奠定了基础.     

煤的电导率随地应力变化关系的研究

从理论上对煤的导电性及其影响因素进行分析,研究得出了煤的电导率随地应力变化的函数关系;在实验室利用专门研制的实验装置通过测定不同煤在承受不同的应力时的电导率值,得出了煤的电导率与地应力之间的变化关系．实验与理论研究的结果相吻合,从而为利用电磁波透视法预测煤层突出危险性技术的研究奠定了基础．     

Correlation of electromagnetic radiation emitted from coal or rock to supporting resistance

More accurate forecasting of rock burst might be possible from observations of electromagnetic radiation emitted in the mine. We analyzed experimental observations and field data from the Muchengjian coal mine to study the relationship between electromagnetic radiation signal intensity and stress during the fracturing of coal, or rock, and samples under load. The results show that the signal intensity is positively correlated with stress. In addition, we investigated the change in the electromagnetic radiation intensity, the supporting resistance in a real coal mine environment, and the coal or rock stress in the mining area. The data analysis indicates that: 1) electromagnetic radiation intensity can accurately reflect the distribution of stress in the mining area; and, 2) there is a correlation between electromagnetic radiation intensity and supporting resistance. The research has some practical guiding significance for rock burst forecasting and for the prevention of accidents in coal mines.