Comparison of two near-field blast vibration estimation models: A theoretical study

Abstract

Blast-induced rock damage has been directly related to blast vibration by many researchers. The common measurement of blasting vibration is in terms of peak particle velocity (PPV). The levels of peak particle velocity at which the rock damage occur are termed as threshold levels of PPV for rock damage. As rock damage is a phenomena occurring very close to the blast holes (?1 m), the peak particle velocity levels at the point of damage cannot be measured directly. Thus, the threshold levels of peak particle velocity for rock damage are estimated by using different near-field blast vibration estimation models. These models essentially use the vibration predictors established from the vibration measurements taken at a safe distance. The most common two techniques of near-field vibration estimation models are the mathematical summation of peak particle velocity resulting from the elemental charge column and the integrated peak particle velocity for the charge length i.e., zero to charge height. However, till date the scope of application of near-field estimation models is limited to single-hole blast only. This paper incorporates a review of the near-field blast-vibration estimation models. Apart from this, an extension of a near-field vibration estimation model for a row of periphery holes is also presented. A theoretical comparison is also made in between single-hole model and row of holes model for estimating the threshold peak particle velocity levels for overbreak in a drift. Similarly, the damage profiles for both the cases are also developed and presented. � 2013 Taylor & Francis Group.