Abstract
The spacing–burden (S/B) ratio plays significant role on rock fragmentation and proper utilization of explosive energy to minimize the undesirable damage. Low S/B ratio generates fine fragments due to pressure rings coalescence of two blast holes, whereas boulder generations were observed above optimum S/B ratio. Both conditions are not acceptable because of wastage of explosive energy. Therefore, to resolve this issue, a numerical model study was conducted to optimize the S/B ratio and to envisage its effect on rock fragmentation based on utilization of explosive energy. Finite element simulation tool was used to see the extent of two blast hole influence area variation with varying S/B ratio. The better results were obtained at S/B ratio of 1:2 with optimum utilization of peak explosive energy. The performance was observed based on peak kinetic energy, peak pressure, radial and hoop stresses on centre of the two blast holes, where pressure rings coalescence.