Abstract: In order to deeply understand the characteristics of coal spontaneous combustion in goaf of gob-side entry retaining in thick coal seam with easy spontaneous combustion，taking 30109 fully mecha⁃ nized caving face of Wuhushan Coal Mine as the research object，the numerical simulation model of coal spontaneous combustion in goaf is constructed，and the gas migration law and coal spontaneous combustion characteristics in goaf of gob-side entry retaining are numerically simulated and analyzed. Based on the con⁃ clusion of numerical simulation，the targeted control measures of gas overrun in the upper corner of 30109 working face，the prevention and control measures of coal spontaneous combustion in goaf and the safety monitoring measures are formulated. The results show that the buried pipe drainage in the upper corner of the working face can effectively control the gas overrun，and different buried depths correspond to different optimal drainage flow rates，and the two approximately satisfy the positive exponential function relationship. The air volume and air leakage rate of the working face and the gob-side entry retaining are the main factors affecting the spontaneous combustion of coal in the goaf. The air supply volume of the working face has a qua⁃ dratic parabolic function relationship with the width of the heat dissipation zone and the width of the oxida⁃ tion zone in the goaf. The goaf near the gob-side entry retaining and the corresponding goaf of the tail road⁃ way are the areas with high risk of coal spontaneous combustion. Comprehensive prevention and control mea⁃ sures can effectively avoid spontaneous combustion of coal in goaf of gob-side entry retaining in thick coal seam with easy spontaneous combustion. The research results can provide theoretical guidance and practical reference for the prevention and control of coal spontaneous combustion in goaf under similar conditions.

Key words: spontaneous combustion thick coal seam, gob-side entry retaining, goaf, numerical simu? lation