以杨柳煤矿发生的2号地面钻井喷水-瓦斯事故为实例，采用理论分析和数值模拟相结合的方法，分析了2层厚硬火成岩的相互组合关系，研究了厚硬火成岩下保护层开采覆岩裂隙演化特征和地面钻井发生喷水-瓦斯事故的原因。结果发现：火成岩附近的煤体存在着大量的热解气孔，煤层吸附瓦斯能力增强，因厚硬火成岩的存在，控制了其上覆岩层的运动，弯曲带内存在裂隙与离层长期不闭合的区域，成为水和瓦斯的富集区和运移通道；当厚硬火成岩突然发生强度失稳时，瞬间释放大量弹性应变能，诱导了地面钻井喷水-瓦斯事故的发生。基于此研究结果，提出了厚硬火成岩下复合动力灾害的防治对策。%Based on the water and gas outburst accident of No. 2 surface borehole in Yangliu coal mine,the combination relationship between the two igneous rocks was analyzed using the combining method of theoretical analysis and numerical simulation,strata cracks evolution law under thick hard igneous rock during protective layer mining was researched,and the reason for water and gas outburst accident of No. 2 surface borehole was analyzed.The results demonstrated that the magma intrusion had a specific effect on coal seams.There are large quantities of pyrolysis pores in coal seam nearby igneous rock,which make the adsorption ability of coal seam enhance.The thick hard igneous rock controls the overlying strata movement,a large number of separations and fractures exist in the separation zone for a long time, which provide migration channels and enrichment area for relief-pressure gas and water.The igneous rock releases a lot of elastic strain energy when fracturing suddenly,this induces to the occurrence of compound dynamic disaster.Based on the research results,the prevention countermeasures and suggestions were put forward.
展开▼
