抄録
Blasting to break the rock and structure using energy of explosive is one of the important operation for civil and mining engineering. In this research some test blasting using high-speed camera, high-speed video and precis blasting system were carried out to study the generation mechanism of fly rock caused by blasting. Seven full scale test blasts in the quarry with different quantities of explosives and burden were carried out to study the flying characteristics of fly rock caused by blasting. DDA (Discontinuous Deformation Analysis) was applied for numerical simulation of full scale blasting. The results are briefly summarized as follows;
1. Initial fracture in the model experiment using the glass material was caused by the Hopkinson effect. The separated fragment, considered as a fly rock, then is accelerated in the direction of a free face by the remained stress.
2. The flight distance of fly rock generated near the minimum resistance line have longer compared with other fly rock in the mortar block experiment. The reason is considered that fly rock near the minimum resistance line was influenced easily by the impact stress and the expansion gas generated by the detonator and detonating fuse. Moreover, it was shown to be able to control the flight distance of the fly rock by applying the precise initiation method.
3. The generation situation and the flying characteristics of the fly rock generated in the bench blasting were clarified from full scale test blasting. Moreover, it was shown that DDA was able to apply for the numeric simulation of bench blasting.
