Blasting Analysis on the Basalt of Diack (Senegal) Using the Langefors-Kihlstrom Theory

The study was carried out at the Diack quarry to optimize blasting and reduce costs. The Langefors-Kihlstrom method was chosen for its proven results in blast design. The objective is to evaluate the current blasting parameters and compare them with those obtained using Langefors' approach to adjust and maximize blasting efficiency and operational safety. The Langefors method uses a semi-empirical formula to calculate the maximum allowable Burden (Bmax) based on various rock mass characteristics and explosive parameters. From this Bmax, all other practical parameters, such as practical burden, sub-drilling length, hole depth, and explosive consumption, are derived. The results show that the practical burden of 3.97 m calculated using the Langefors method is acceptable compared to the current 4 m burden used at the quarry, with notable differences in geometric parameters. Regarding loading parameters, the Langefors method suggests an EXPLUS 90 quantity per hole of 21.59 kg and ANFO of 54.78 kg, totaling 76.37 kg per hole. The optimized theoretical calculations led to a 9% increase in blasted tonnage while reducing explosive consumption by 22%, with a powder factor of 300 g/m³, lower than the 387 g/m³ used in the current method, leading to better production. Finally, the Langefors method proves to be more efficient, offering superior breaking power and reduced specific explosive consumption. Thus, its use will reduce blasting costs. Keywords: Blasting, Quarry, Maximum Burden, Langefors Method, Diack