Rock brittleness capacity upon compressive fracture energy dissipation to assess drilling efficiency

Abstract

Rock drilling is essential in the mining industry. Complexities involved in the drilling process encompassing not only rock properties but also the nature of the drilling action impact the drilling performance and operational costs. Brittleness is a fundamental rock property relevant to rock drilling and excavation works. However, rock brittleness is a concept yet to be investigated. In this study, a new brittleness index developed upon fracture energy quantities withdrawn from the complete stressstrain characteristics in uniaxial compression of rock is presented. A vast independent data on the drilling performance reported elsewhere in the literature was evaluated against the new brittleness index. The results show that the proposed brittleness index successfully describes the performance of different drilling methods including PDC (Polycrystalline Diamond Compact) rotary drilling, roller-cone rotary drilling and percussive drilling.