Evaluation of the Atlas Copco relation between burden and blast-hole diameter and rock strength at bench blasting - a case study

In surface mines, a successful blast design provides a sufficient quantity of suitably fragmented and properly placed much at the lowest practical cost. One of the significant variables in such blast designs is the 'burden'. This paper outlines an empirical formula to determine the burden for blast-hole diameters in the range of 25 to 304 mm based on the uniaxial compressive strength of the rock using ANFO as the main explosive charge. The formula has been tested at two working limestone mines in the Sultanate of Oman and it has given very positive results. Thus, besides its possible application for the new mines, the formula can be used to check the existing burden at any working mine.