The fracture field and permeability distribution model of comprehensive working face goaf was integrated upon the theoretical examination to investigate the fracture field distribution law of goaf and gas migration and accumulation characteristics, and this model has been applied to the mathematical model of gas migration and accumulation in goaf. The ANSYS FLUENT numerical simulation software was used to obtain the characteristics of gas migration and accumulation in goaf and its influencing factors and analyze the applicability of solving the features of gas migration and proliferation using the porosity model of layer division in goaf. The results were as follows: the porosity around the caving zone was a little big, whereas the porosity in the middle was a little small. The porosity was almost equal along the inclination and strike in a symmetrical distribution. The porosity occurred at the fracture zone with an “O” shape. As the gob layer height increased, the porosity tended to be small. The maximum value of the porosity of the goaf would shrink to the middle of the goaf with the increase of gob layer height. The gas mass fraction along the goaf inclination showed the growth characteristics of “exponential function”, the gas mass fraction along the goaf strike on the air inlet side showed the growth characteristics of “Boltzmann function”, and the gas mass fraction along the goaf strike on the air outlet roadway side manifested the growth characteristics of “linear function”. The main influencing factors were air leakage speed, negative pressure, and porosity distribution. The distribution model of porosity and permeability of different layers of gob can more accurately simulate the characteristics of gas migration and storage.

In view of the engineering problem whereby the main roof fracture of deep coal seam still induces frequent rockburst after soft direct roof buffering, a UDEC numerical model was established based on the actual geological conditions of a mine, and the influences of the length of hanging roof and periodic weighting step on the stress in front of coal wall were discussed. The dangerous area at most risk of rockburst in the working face was monitored by using core-drilling, the risk of a rockburst was predicted by classification, and countermeasures were taken against all levels of rockburst. The results show that the longer the hanging roof length, the higher the stress in front of coal body; However, when the coal body changes from an elastic state of stress to a plastic state of stress, the stress will suddenly decrease, the range of variation of stress under static load is larger than that under dynamic load, which indicates that shock wave attenuates the stress in front of the coal body. The larger the periodic weighting step distance, the higher the stress in front of coal body, and the greater the increase of stress. However, compared with the attenuation effect of dynamic load, when increasing the hanging roof distance, the attenuation effect of dynamic load under the condition of increasing the periodic weighting step distance is greater. Dynamic load or static load will increase the stress in front of coal wall, which will lead to a rockburst. The techniques of large-diameter borehole pressure relief, coal seam water injection, and pressure relief blasting can be used to control the high-stress area monitored, ensuring the safe mining of the working face, so that coal resources can be extracted efficiently, and the rate of utilization of coal resources can be improved.