Numerical simulation analysis of the influence of roof weakening on the mining of seam 4-1adopted longwall with top-coal caving in Anjialing underground coal mine

The paper analyses the law of the influence of roof weakening on the mining of seam 4-1 adopted longwall with top-coal caving in Anjialing coal mine compared with the roof in natural state. The roof of seam 4-1 has great impact on the mining of working face in natural state, while the impact is decreased after it is weakened. When the weakening coefficient is 0.067, the distance of periodic roof pressure will be decreased to less than 20m, which can guarantee the normal mining of working face and comparatively high recovery ratio of top-coal.