【作者】 陈新生；

【导师】 何俊；

【作者基本信息】 河南理工大学 ， 安全技术及工程， 2009， 硕士

【摘要】 瓦斯含量、涌出量大小和煤与瓦斯突出的发生受地质构造演化条件的控制,并且存在着明显的分区、分带特征。地质构造在形成过程中,对于煤层原有形态进行了强烈的改造,构造演化过程中剪切挤压作用不仅使煤层的结构遭到破坏,而且改变着煤层中的应力场,这对于煤层中的瓦斯的生成、赋存和运移都具有重要的影响。地质构造是将煤层中瓦斯、地应力和煤的物理力学性质三者联系起来的纽带。在古构造应力场的作用下,地质构造演化对煤层结构的变形破坏起到作用,它主要影响的是煤体的结构和力学性质,以及瓦斯的生成和保存。已存在的地质构造在现今构造应力场的作用下,对于煤与瓦斯突出有直接控制作用。基于此观点,本文通过对水平煤层在构造应力作用下生成褶皱和断层的过程进行有限元数值模拟,研究在一次构造作用下,煤层的变形破坏情况。定量的解释了无论是背斜还是向斜,在轴部附近煤层容易破坏的原因,同时确定了破坏发生的大概范围,对煤层中瓦斯的逸散、聚集情况做了出了定性的分析。还发现接近断层面的下盘煤层底部和接近断层面的上盘顶部,煤层容易遭受破坏,是容易生成瓦斯含量异常区的地方。然后对含有褶皱和断层构造的煤层做了其在现代构造应力场下的地应力数值模拟,研究地质构造带煤层中地应力场的分布特征,确定出了这两类地质构造中容易积聚弹性能的部位,对煤与瓦斯突出的可能性做了定性分析。通过对煤层古今地质构造带受力变形、破坏的数值研究,有助于更加准确的预测煤与瓦斯突出在煤层中的分区和分带特征。更多还原

【Abstract】 Gas content, emission size and coal and gas outburst happened is controlled by the evolution process of the geological structure. And there is a clear partition, sub-band characteristics. In the process of forming geological structure,the original form of seam had been strongly transformed. Shear and extrusion process of the tectonic evolution not only destructed the coal structure but changed the stress field in coal seam. It had an important implication on coal seam gas production, storage and migration. Geological structure is the bonds that link the coal seam gas, the in-situ stress and the physical and mechanical properties of coal.At the ancient tectonic stress field, the geological structure evolution played a role on the coal seam deformation and failure. It mainly affected the coal structure and mechanical properties, as well as gas generation and preservation. The modern tectonic stress dominates the earth stress,and takes part in outburst directly.Based on this opinion, through finite element simulation on the process of seam generating folding and fault at the level of tectonic stress ,the paper analyzed the coal seam deformation and failure situations. It made a quantitative interpretation on the reasons for the destruction in the easy axis of either the anticline or syncline. Also, it determined the probably destruction scope and made a qualitative analysis on the gas oven or gather situation. It also found seam was vulnerable to damage at the bottom of seam footwall and the top of hanging wall where may contain abnormal gas content. Then it simulated the seam in-situ stress in coal seam when the seam had contained geological structures such as its modern tectonic stress field folding and fault. From the results, it identified where elastic energy was easily accumulated in these two types of geological structures and made a qualitative analysis of the possibility of coal and gas outburst. Through the numerical study on ancient and geological structure it would contribute to a more accurate grasp of coal and gas outburst district and sub-band characteristics in coal seams.更多还原