Modelling the effects of blasting on paste fill

Abstract

Numerical modelling is being used to simulate the response of paste backfill to underground blasting. Paste fill is a cemented backfill used to fill the void left by mining to provide stability to the mine. The extraction process in open stoping mining involves blasting adjacent to paste fill. If the paste fill becomes unstable due to the blast loading. it may displace into the void. The finite clement numerical modelling package A BAQUS/Explicit was used to model the behaviour of paste fill due to adjacent blasting in an underground mine. A paste fill stope was monitored during the extraction of two nearby stopes, and a series of field tests were carried out to provide data to validate the numerical models. The validated models were then run for different paste fill mixes, to observe the changes in paste fill response for different mixes.