Safe mining and blasting technologies for Dabaoshan mine in mined-out and subsidence area

The mining operation becomes very dangerous after the goafs collapsed in Dabaoshan Mine. Meanwhile,the blasting process does not work correctly because of the integrity of collapsed rock is damaged and fractured. In order to solve the technical problem,a large advanced exploration methods was developed. The GY-200-1-type engineering drillers explore the mined-out and subsidence area combined with the CM351-type downhole drillers. The explosive energy will not release by reducing the bench height,optimizing blasting parameters and charging structure. The excavators,hydraulic hammers,handheld pneumatic rock drillers are also used to solve effectively the impact of drilling,charging,blasting effect which were caused by the cracked rock in the mined-out and subsidence area. Ultimately,the ore is explored safely. At the same time,Dabaoshan Mine can be mined normally and lay foundation for sustainable development.