A review of the development of better prediction equations for blast fragmentation

The development of prediction formulas for the fragmentation from bench blasting has been reviewed, starting with Koshelev et al. (1971) and Kuznetsov (1973). Much attention has been paid to the Kuz-Ram model (Cunningham 1983, 1987 & 2005), its development, its errors and the mean vs median misunderstanding. The work by the USBuMin (Stagg et al. 1990, Otterness et al. 1991) and by Chung & Katsbanis (2001) are reviewed as are the JKMRC models by (Kanchibotla et al. 1999, CZM) & Djordevic et al. (1999, TCM) developed to cope with the underestimation of blasting fines. The change brought by the Swebrec distribution (Ouchterlony 2005) and the associated KCO model is described. Studying distribution-free fragment sizes x_P for an arbitrary mass passing P led to the discovery of the fragmentation-energy fan (Ouchterlony et al. 20017a) and, with the help of dimensional analysis to the new fragmentation prediction model x_P -frag (Sanchidrián & Ouchterlony 20017a), which has much lower errors than the Kuz-Ram and CZM models.