Effect of distance and direction on ground surface vibrations generated by array blasting: A numerical study

Array blasting is commonly used to facilitate the removal of near-surface rock masses for excavation purposes. When operating in the vicinity of structures, vibrations caused by blasting are typically monitored using velocity-sensitive transducers at the ground surface, and vibration measurements are quantified in terms of peak particle velocity (PPV). Weight of explosive and distance from the blast array are typically used as the main criteria to identify potential locations of damaging vibrations. However, numerical modeling of PPV fields surrounding a simple blast array reveals variability and asymmetry within the PPV field and demonstrates that PPV is dependent on both the distance and direction from the blast array as well as the quantity of explosives. These results demonstrate that longer delay periods between blasts in an array generally result in a reduction in PPV in the vicinity of the array. The results presented herein demonstrate that it may be beneficial to perform pre-survey numerical simulation of blast-induced vibrations to identify zones that are susceptible to excessive vibration levels.