Blast Fragmentation Screen - 2D Size Distribution and Screen Deck

Fragment size distribution

Quarry rock breakage is described statistically. The Kuz-Ram model gives the mean fragment size X₅₀ = A (V/Q)^0.8 Q^1/6 (115/E)^19/30 in cm, with A the rock factor, V the rock volume per hole (m³), Q the explosive mass per hole (kg) and E the relative energy of the explosive (a plain reference mix = 100). The fraction passing size x follows the Rosin-Rammler law R(x) = 1 - exp[-ln2 (x/X₅₀)ⁿ], where the uniformity index n (typically 0.8 to 2.2) improves with accurate drilling and a good burden-to-diameter ratio.

Screening

A screen deck with square aperture a passes pieces smaller than a. The undersize fraction equals R(a) and the oversize fraction 1 - R(a) is returned for further crushing. The animation draws pieces from the same distribution with a seeded random generator and counts what falls through, which is compared with R(a).

Honest simplifications: a pure empirical model with no blast-design instructions: it shows how a size distribution responds to inputs and why oversize is recirculated. Real screening efficiency is below 100 % for near-size pieces, moist rock blinds the deck and the model ignores fines from crushed zones. This page is educational statistics about inanimate rock, not a design tool.