ABSTRACT
According to the position of initiating charge in the blasthole, there are three different initiation methods (i.e., top, bottom and central initiation). The influence of these three different initiation methods on blasting fragmentation is studied in this paper. In top initiation, the initiating charge is in the upper part of the blasthole, and the energy focusing wave of the detonator and the detonation wave propagate towards the bottom of the blasthole. In bottom initiation, the initiating charge is in the bottom of the blasthole, the energy focusing wave of the detonator and the detonation wave propagate towards the collar of the hole. When the initiating charge is in the middle of the hole, it is the case of the central initiation. The initiation position and the explosion shock wave propagation have an influence on fragmentation. The pressure on the blasthole bottom is analyzed quantitatively and the three methods are compared in this section.
