The influence of delay timing on optimal fragmentation in electronic blasting

摘要

This paper highlights some of the most recent developments in advanced blasting using the newly developed electronic detonators and initiation systems. It is shown that knowledge in wave propagation and fracture mechanics is essential for the successful industrial application of the new blasting technique. In particular, the delay time, the acoustic impedance mismatch, the wave speeds in the rock and the shape of the wave form have become decisive parameters. Utilizing the speed and the shape of detonation waves one finds that the advanced blasting technology requires shorter delay times in conjunction with wider drilling pattern and grossly reduced amount of explosives, i.e. a lower powder factor: This seemingly contradictory arrangement is fully justified by using scientific principles in blasting, and converting blasting from an art into a scientific discipline.