Abstract

Peak particle velocity (PPV) is an important parameter in estimation of rock and structural damage. In general, ground vibration is measured using a seismograph at a distance from the blast face to keep the instrument safe. However, rock damage due to blasting occurs very close to the blast hole and thus, PPV at the damaged zone can not be measured directly. In the far-field observations charge is considered as point source because the distance of measurement is significantly longer than the charge column length. However, in near-field PPV estimation charge length can not be ignored. Thus, a mathematical model is developed for estimation of near-field PPV. In the proposed model, effect of an elemental charge in the charge column is calculated and then summed up for the whole charge column. Thus, it is assumed that blast waves from all the elemental charges of charge column reached at the point of interest at same time. This can be helpful in assessing the extent of blast-induced rock damage.

Key words: Near-field PPV, rock damage, blasting.