The Application of Pre-Cracking and Loosening Boasting on Sublevel Caving Coalface used Blasting

This paper introduce basic principle of presplitting and loose bursting with roof coal,knows parameter of presplitting and loose bursting,it counts out theoretical value in 1402 workface JinLiShan coal mine JiaoZhuo bureau with this principle,combining application situation of other coal mine and festing again and again it gets out bursting parameter,roof coal mining goes on smoothly,it has good vesult.