深井突出煤层深孔聚能造缝固粒射流增透消突机理研究

Coal and gas uotburst disaster is easy ccurrencr in deep low permeability of coal and gas outburst coal seam mining process . Aimed at difficulty on gas drainage from low permeability coal-beds and foundational theories and technical problems in gas prevention and control engineering, and exploring theory evidence and technical methods for directional cohesive energy explosion in low permeability and high gas coal-beds. According to the similarity theory construct fractures evolution model of directional cohesive energy explosion, taking advantage of experiments on 3D model experimental platform with automatic compensation for hydraulic loading system, combined with theoretical analysis and numerical calculation method, study fracturing mechanism by directional cohesive energy explosion, explore impacts on energy transformation by different directional energy concentrator structure as well as force and energy interaction mechanism of fracturing coal by directional force. Analyze the fracture evolution process of directional explosion - explosion acting, explosion shock and explosion gas fracturing coal, and the action mode and process of the external force or external load on fracturing results. Experimental research the theory and method of long-term maintain high permeability by embed solid particles to prevent the fracture close. The research involves the theoretical issues of mine safety theory and technology, rock mechanics, damage mechanics, explosion and shock, porous media fluid dynamics and trace measurements, and the research results provide theoretical methods and new ways to promote permeability of low permeability coal-beds and realize high-efficiency gas drainage.

深井低渗透性煤与瓦斯突出煤层采掘生产过程中易发生煤与瓦斯突出灾害。项目采用将固体颗粒嵌入聚能药柱内，在煤层内聚能定向爆破造缝，同时形成固粒射流，固粒被"气楔"强行嵌入造缝裂隙中阻止煤层缝隙闭合，使煤体强化增透并具有长效性，获得高效抽采瓦斯效果，实现深井突出煤层局部快速消突。根据岩体损伤、爆炸力学原理构建突出煤层聚能爆破造缝固粒射流模型，在自动补偿液压加载系统的深井煤与瓦斯突出试验台上试验和动力学数值计算方法相结合，寻求最佳造缝效应的聚能药柱结构及固粒嵌入式药柱制备方法；破解聚能射流形成"气楔"劈裂煤体，并强行将固粒嵌入裂隙中的力能作用机制；分析不同粒度、密度的固粒射流嵌入不同性质煤岩裂隙中的分布形态及阻止缝隙闭合增透效应；试验研究不同性质的煤岩爆破造缝固体颗粒支撑缝隙，和相同煤岩爆破造缝采取不同固相颗粒支撑缝隙对煤层增透效果，分析聚能造缝固粒射流煤层渗透性变化特性。探索聚能造缝固粒射流增透消突机理。成果对提高低渗透性高煤层渗透率高效抽采瓦斯，为快速局部消除煤与瓦斯突出提供理论方法和技术途径。

深井低渗透性煤与瓦斯突出煤层采掘生产过程中易发生煤与瓦斯突出灾害，主要是低渗透性煤层内的瓦斯不易抽出来，为此寻求煤层强化增透方法。项目主要采用将固体颗粒嵌入聚能药柱内，在煤层内聚能定向爆破造缝，同时形成固粒射流，固粒被"气楔"强行嵌入造缝裂隙中阻止煤层缝隙闭合，使煤体强化增透并具有长效性，获得高效抽采瓦斯效果, 寻求消除煤与瓦斯突出的新方法。. 根据岩体损伤、爆炸力学原理，在深井煤与瓦斯突出试验台上进行突出煤层聚能造缝固粒射流增透试模拟验，获得了聚能定向爆破作用下，煤层劈裂及裂纹扩展和固粒嵌入裂隙的动力学特征以及爆轰能量形成的“气楔”效应。构建了突出煤层深孔聚能造缝固粒射流“气楔”作用下煤体损伤本构模型。用试验和数值计算方法，优化设计聚能药柱结构，成功研制了具有最佳造缝效应的聚能药柱结构及固粒嵌入式药柱制备方法；得到不同粒径、密度的固体颗粒（如石英砂、陶粒砂）和不同瓦斯压力下的煤层，在聚能爆破“气楔”劈裂煤体驱动固粒射流，固体颗粒嵌入煤层裂隙中的分布态态及阻止缝隙闭合增透效应。找到了获得最佳聚能造缝增透效果的途径。研究了聚能造缝固粒射流爆轰能量作用下，低渗透性煤层基本物理性质变化的力学特性、煤体应力变化规律、煤层瓦斯吸附、解吸和瓦斯输运特性。探索了煤体增透前后的瓦斯吸附、解吸和放散时间长度及增透区内的瓦斯分布场规律。研究发现聚能定向爆破与普通爆破相比，可使煤层造缝宽度提高1.6倍以上，固相颗粒支撑缝隙致煤层渗透性增透的持续时间大大延长。. 科学价值在于探索提高低透气性高瓦斯煤层渗透率的理论方法和技术途径，改进完善低透气性高瓦斯煤层瓦斯抽采理论，寻求防治煤与瓦斯突出的新方法，为有效预防和控制低透性高瓦斯煤层瓦斯灾害发生的技术和方法奠定理论基础。