The effect of detonator position on rock fragmentation was studied at the Kevitsa open pit mine. Five full-scale field tests were conducted where blasts divided into test and reference areas, compared with each other. In detonators placed or near middle point explosive column, in corresponding to conventional used mine, about 1–2 m above bottom blast holes. fragment sizes from both areas measur...

Paleocene plutons on Kodiak Island, in Alaska, contain host-rock xenoliths that have undergone varying degrees of fragmentation, metamorphism and assimilation in the surrounding granitoid rocks, and therefore provide an excellent natural laboratory to study the processes of xenolith fragmentation and magma contamination. Kodiak Island has two belts of Paleocene plutons: the Kodiak batholith tha...

[1] Flow processes in unsaturated fractures considerably differ from flow in rock matrix because of the dominance of gravitational forces, accentuated by variations in fracture geometry. This gives rise to liquid fragmentation, fingering, and intermittent flow regimes that are not amenable to standard continuum representation. We develop an alternative modeling framework to describe the onset o...

Delay time is an important factor in the quality of bench blasting. The development and application electronic detonators make it possible to control timing detonation by a highly precise delay time. It easily achievable way seek better blast fragmentation controlling In order investigate influence on rock fragmentation, eight experiments blasting models with double holes were carried out. aver...

A review of breakage and fragmentation modelling literature has shown that only a few methodologies have been specifically developed for applications in underground production blasting. These approaches however, have applied empirical relations that do not adequately consider ring blasting geometries; have failed to appropriately respond to changes in basic design input parameters; and have pro...

Abstract The rock fragmentation and crack propagation of anisotropic induced by tunnel boring machine (TBM) tunneling is studied in this paper. First, a numerical model based on the 2D particle flow code (PFC2D) established calibrated to reveal four stages fragmentation. In Stage I (indentation depth 0–0.4 mm), indentation force beneath cutterhead increases decreases dramatically with accumulat...

While empirical rock fragmentation models are easy to parameterize for blast design, they usually prone errors, resulting in less accurate fragment size prediction. Among other shortfalls, these may be unable accurately account the nonlinear relationship that exists between input and output parameters. Machine learning (ML) algorithms potentially able better relationship. To this end, we assess...