Abstract: In order to study the increased permeability effect of strata penetration deep-hole blasting in the high gas content and low permeability coal seams, taking No.13-1 seam in Huainan mine as the engineering background，a method, strata penetration blasting with coal-rock interface charging was proposed. In addition, explosion models for testing the effect of increased permeability were designed. When the charge exploded, the signal of dynamic strain between coal seam and rock formation were tested with the ultra-dynamic testing system and then crack distribution was observed. The results show that stress waves reflection stretching appeared in interface which lead to coal-rock interface separated, cracks and gas holes are interconnected, three-dimensional reticulation of gas drainage channels is formed. Meanwhile, the explosion caused a strong disturbance to coal seam and it works very well. This technique had great theoretical value and practical significance for strata penetration deep-hole blasting and increased permeability in coal seams with the high gas content and low permeability.

Key words: strata penetration deep-hole blasting, explosion model testing, coal-rock interface charging, gas drainage channels, charge technology