The Influential Role of Confinement, Charge Factor and Segmentation of Explosive Charge in a Blasting Round: A Perspective for the Blasting-Induced Ground Vibration Compliance

Abstract

This paper focuses on evaluating the effects of confinement, charge factor and segmentation of holes in a blast round on blast-induced ground vibrations in a mine. The study involved conducting a series of experiments with different drillhole diameters and modifying design parameters. The results indicated that the initial blast designs were not optimised, resulting in to generation of higher magnitudes of ground vibrations. Based on the vibration data recorded, regression analysis was carried out to establish a best-fit relationship between the scaled distance and vibration. On the basis of the threshold values of peak particle velocity prescribed by the DGMS, the permissible maximum charge per delay at specific distances were determined. The permissible charge values were not workable and matching with the mine productivity. The subsequent experimental blast with a smaller drill hole diameter also did not significantly reduce the magnitudes of ground vibrations. However, the experiments conducted with reduced confinement conditions with less number of holes and optimized charge factors resulted in a notable reduction in the ground vibration magnitudes. An innovative technique of segmentation of total holes in a blasting round using electronic detonators demonstrated a significant decrease in vibration magnitudes with the potential of increased productivity. The findings of the study emphasize the importance of re-assessing the blast design parameters and charging patterns to mitigate ground vibrations and optimize the blast outcomes in mining operations.