Minimization of secondary fragmentation with a view to enhancing the blasting economics

Abstract

Construction materials have a huge demand and become an expensive commodity due to limited quarry activity. Further Research and Development (R and D) is very important in quarry industry in order to minimize the cost of quarry products in Sri Lanka. Cost of secondary fragmentation is a significant factor in this regard. This research is aimed exploring the methods at reducing the fragmentation cost effectively. Formation of the boulders mainly depends on the geological diversity, bench parameters and varying powder factor. Site geology is a natural factor that cannot be adjusted but the bench parameters and the powder factor can be changed over wide range to reduce the boulder formation. Three consecutive blasts were designed by the project team. The bench parameters and powder factor were determined to control the formation of the boulders.The plan views of the blasted muck piles were photographed to analyse the particle size distribution of the muck pile.