Return on experience from full-scale open pit blasting experiments

Abstract : This paper gives practical feedback from an ambitious full-scale blasting program financed by AREVA MINES in 2010. The 32 experimental blasts consisted in single-hole, dual-hole and one-row (max. 5 holes) blasts in order to propose a fragmentation prediction method on a hole-by-hole basis. The horizontally-layered sandstone was blasted with ANFO in 6" diameter holes with bench heights between 10 and 17 m. Muckpile fragmentation measurements were set up to this aim at AREVA MINES's SOMAÏR open pit mine (Niger) according to standards; 2D truckload pictures were taken, sampled and processed with MINES ParisTech's FragScan software. Our paper emphasizes how site specific conditions and a highly productive environment (around 130 kt rock moved every day) restrain experimental possibilities, and practical recommendations to future experimenters are accordingly proposed.