我国是世界上煤炭资源较丰富的国家，同时也是世界上煤层瓦斯灾害问题频发的国家。新疆乌鲁木齐矿区急倾斜煤层的探明储量占我国急倾斜煤层总量的1/4以上。急倾斜煤层的赋存条件、煤层结构、应力环境等都比其它类型煤层特殊，在其综合机械化放顶开采过程中瓦斯气体在工作面采空区的运移规律更比其它条件煤层下复杂，煤层综放开采工作面瓦斯涌出量大，导致工作面瓦斯超限频繁，尤其是工作面上隅角，已对综放工作面安全、高效生产构成了严重的威胁，且瓦斯不均衡分布容易发生积聚导致爆炸事故。因此，研究煤炭开采过程中瓦斯运移规律具有重要的科学意义和经济价值。 本文以急倾斜煤层综放开采过程中瓦斯运移为研究对象，在总结前人相关研究成果的基础上，对乌东煤矿现场开采技术条件、煤层地质特征和致灾机理等方面进行系统调查和认识的同时，采用理论分析、物理相似模拟实验和数值模拟等科学方法及技术手段，对急倾斜煤层综放开采条件下瓦斯运移规律进行了研究，并结合现场开采实践，对开采技术条件进行相关改进从而保障了安全高效的开采。通过上述研究内容，得到以下结论： 1、以乌东煤矿井田+620水平45#煤层西翼为实例，在实验室按照1：100的相似比例设计采场模型进行了物理相似模拟实验。实验表明：注水条件下瓦斯浓度明显较未注水条件下的在整体上要高；放顶煤阶段注水条件下的瓦斯气体浓度的递增趋势和变化率较未注水条件下瓦斯浓度更加明显；顶板冒落阶段在注水和未注水条件下的瓦斯气体浓度从工作面上部到顶板冒落处都呈现梯度式降低变化规律。 2、结合45#煤层西翼回采工作面实际参数，建立了相应的物理模拟并进行了数值模拟实验。实验表明：采空区瓦斯浓度分布在采空区的走向方向上，从工作面到采空区深处，瓦斯浓度逐渐升高；在倾斜方向上，从下隅角到上隅角，瓦斯浓度是逐渐升高的，上隅角瓦斯浓度超标明显，需要进行抽放；在竖直方向上，从采空区的底板到采空区的老顶范围内，其瓦斯浓度呈现增大趋势。 3、针对+620水平西翼45#煤层实际回采中的问题，进行了地质雷达探测技术的应用，并对该水平面的通风系统等生产条件进行了优化设计和瓦斯抽放实践。结果表明：经过通风系统优化和瓦斯预抽放工程的实施，+620水平西翼45#煤层的回采生产条件得到有效安全保障，开采效率得到显著提高。

There are plentiful coal resources in our country, and the problems from gas hazards also took place frequently. The reserves of steep coal seam in Urumqi Xinjiang mining area occupy more than a quarter of the total of China’s steep seam. The occurrence conditions, coal seam structure and the stress environment are different from the other types of coal seam. In the process of the fully-mechanized caving mining, the gas migration mechanism of the working face and goaf are more complicated than the other condition of coal seam. The amount of gas gushed from the working face resulted in gas overrun frequently, especially on the upper corner of working face. That brings about a serious threat on the safety of working face and efficient production. In addition, due to the uneven distribution of gas, the explosion accidents would happen easily and result in heavy casualties and huge economic losses. Therefore, the research on gas migration mechanism in the process of coal mining has an important scientific significance and economic value. Papers mainly research on the gas migration mechanism of steep thick seam in fully mechanized top-coal caving. On the basis of summarizing the predecessors’ research results, and we systematic investigate the production technology conditions of the Wudong coal mine, the geological characteristics of coal seam and the mechanism to cause disasters. At the same time, using the theory analysis, the physical simulation experiments, the numerical calculation and other technical methods, we researched on the gas migration mechanism of steep thick seam in fully mechanized top-coal caving. In addition, combined with locate production practice, we improved technical conditions of mining and guaranteed the safety and efficiency of mining. The main contents and conclusions are summarized as follows: With the 45# coal seam of +620 level of the Wudong mine as the example, we built a stope model on a similar scale of 1:100 and did the physical simulation experiments in the laboratory. Experiments show that the gas concentration in the condition of water flooding is higher than not under the condition of water injection. Besides, on the stage of the top-coal caving, the increasing trend and the rate of gas concentration in the condition of water flooding is more obvious under the condition of less water injection. On the stage of the roof caving, gas concentration in the condition of water flooding and less water injection appear reduce in gradient type. Combined with locate working face’s parameters of 45# coal seam, we established the corresponding physical model and carried out the numerical simulation experiments. The experiments show that the gas concentration is increasing from working face to deep goaf in the goaf towards direction. On the tilt direction, the gas concentration is increasing from the down corner to the upper corner. It needs to be taken out because the gas concentration of the upper corner exceeded standard. Meanwhile, the gas concentration shows a trend of increase from goaf floor to the old roof in the vertical direction. Aimed at the realistic problems of the 45# coal seam of +620 level, we had carried on the application of geological radar detection technology, and taken the optimized design of the ventilation system and the gas drainage practices. The results show that the production conditions and the production efficiency of the 45# coal seam of +620 level are improved after the ventilation system optimization and implementation of gas pre-drainage engineering.