Numerical simulation of the blast response of cemented paste backfilled stopes

The effects of underground blasting on stress wave propagation, blast response and generation of pore water pressures in cemented paste backfilled (CPB) stopes is researched in this study. Through LS-DYNA the effects of sequencing of detonation and number and blasthole proximity on the total and residual pore pressures exerted in the fill was explored. Results show that liquefaction risk decreases as explosives are detonated in rows located perpendicular to stope's exposed face with delay times in excess of two milliseconds. Cementation of CPB was not observed to affect blast induced pressures in fully saturated backfills but decreases liquefaction risk.