关键词: 工作面末采, 冲击地压, 断顶爆破, “高+低位”爆破, 应力路径阻断

Abstract: Aiming at the problem of the design scheme of anti scour roof blasting in the withdrawal channel of nalinhe No. 2 mine, from the perspective of stress blocking and positive protection of the withdrawal channel, the design scheme of roof blasting is designed and optimized, and the obvious technical advantages of "high + low" blasting are analyzed and verified. First, in terms of blasting induced cracking and crushing, the "high + low" series one-time blasting and the superposition of vibration stress waves enhance the cracking and block crushing effect in the blasting area, reduce the change gradient of blast hole stress in the blasting affected area by 37.5% - 40%, enhance the function of blocking high stress transmission, and avoid the superposition of mining stress and coal pillar concentrated stress impact disaster force source; Second, in terms of blasting scale, the stress transmission path within the range of short-range rock stratum (10 times mining height) affecting the impact behavior of the working face is eliminated, the pressure relief blind area is avoided, the blocking of the whole layer is realized, and a positive protective effect is formed on the main withdrawal channel.