An investigation on the effect of specific charge on the downstream quarry operations :

Abstract

The value of specific charge in open pit quarry blasting processes considerably affects the efficiency of the blasting. Specific charge is defined as the mass of explosives required to break a unit volume of the rock. When the specific charge was increased from 0.88 to 0.94, the mean rock fragmentation size reduced from 39.16cm to 34.19cm and a decrease in specific charge from 0.94 to 0.88 increased the mean rock fragmentation size from 34.19 cm to 41.82cm. This research study provides awareness about the effect of specific charge on fragmentation size after blasting and the duration, working capacity and fuel and energy costs incurred in the downstream quarry operations carried out at SICL quarry. The mean fragmentation sizes, the unit costs of loading, crushing, and boulder crushing and specific charge values were separately determined in each blast test. Afterwards, the specific charge values were interrelated according to duration, working capacity and costs incurred in loading, crushing and secondary rock breaking. Recommendations have been suggested on further analysis on the effect of specific charge on the downstream quarry operations