Blasting Operations Using Different Initiation Methods in Deep Underground Mines

Résumé : Among different types of hazards associated with underground mining in Polish copper mines, one of the most dangerous is rock burst hazard. Having in mind that the depth of exploitation is getting deeper, this problem will likely get worse in the near future. This kind of hazard is connected inherently with seismic events. Controlled group blasting within a potentially unstable roof stratum is considered as an active method of rock burst prevention. A number of recorded seismic events can be clearly and directly explained by the blasting works effects. With electronic detonators, it is possible to achieve a precise delay time between the detonation of explosives in the individual blastholes and mining faces. Within the framework of this paper, the analysis of seismograms recorded during selected blasting works differing in applied initiation systems, i.e. non-electric and electronic was carried out. It was assumed that this approach may be treated as a new blasting method of rock burst control in deep mines conditions or can be the basis for the modification of the currently used method.