Experimental investigation of fragmentation enhancement due to Salvo impact : Barker, D B; Holloway, D C; Cardenas-Garcia, J F Proc 23rd Symposium on Rock Mechanics, Berkeley, 25–27 August 1982, P441–448. Publ New York: AIME, 1982

Abstract

Tround International Inc is currently developing a hard rock drill that uses a salvo of three frangible projectiles to prefracture the rock ahead of a conventional tri-cone bit. This paper reports on a series of experiments conducted for Tround to study the fragmentation enhancement possible through the use of an optimally timed and spaced salvo of projectiles. In this study the complex three-dimensional problem was simplified to a two dimensional salvo impact problem in a transparent brittle plate of glass. The use of high speed photography and dynamic photoelasticity was then used to study the development of the impact damage zone and the various interactions of the stress waves. For the covering abstract of the symposium see TRIS 452576. (Author/TRRL)