ABSTRACT

Mining industry relies heavily on drilling and blasting for any excavation project as it is cost effective and applicable for wide geo-mining conditions. Thus, need of the hour is to make this method as efficient as possible to achieve timely completion of projects from higher drivage rates. During blasting, only a small part of the shock energy released from the explosive is utilized for fragmentation and displacement of rockmass. The rest is dissipated as ground vibration all around the blast hole. Ground vibration is measured by seismographs in terms of Peak Particle Velocity (PPV) at the point of monitoring. Statistical analysis of the measured PPVs helps in establishing the vibration predictors, i.e., the ground and propagation characteristics. These vibration measurements are carried out at a longer distance to keep the seismographs safe and within their measurable range and the explosive charge is considered as a point charge. In case of blast induced rock damage, the damage extent (point of interest) is very close to the blast hole and thus the seismographs cannot be placed at that spot. Further, the prediction of vibration threshold

R0c = allowable overbreak distance (m); ql = Linear charge concentration (kg/m); K and α are constants based on site characteristics.