Optimization of fragmentation in underground blasthole mining

A research project on fragmentation in underground blasthole mining has been initiated. The purpose of the studv is to optimize fragmentation. Factors influencing size distribution and amount of oversize material, as well as consequential costs related to fragmentation are reviewed. The optimization approach used involves an iterative integration of three computer modules. The first module is a commercially available program for predicting relative blast fragmentation as a function of drilling and blasting parameters. The second module, developed in-house, is a Load-Haul-Dump simulation program using both deterministic and stochastic elements and is well suited for assessing fragmentation effects on haulage production. The third module, integrates drill, blast and fragmentation parameters from the first module and performance parameters from the second module for a range of scenarios, to evaluate total system economics.