JOURNAL PAPER

 

Controlled blasting for enhanced safety in the underground environment

 

 

E.J. Sellers

AEL Mining Services

 

 

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SYNOPSIS

Good blasting practices based on the careful application of explosive energy lead to significantly safer mining operations. Case studies demonstrate how the selection of the correct charge mass, explosive type and round design are vital for extracting the exact amount of rock required and preventing spurious damage to the remaining rock mass. In other cases the explosives are applied to precondition the rock mass, design rockburst resistant support, prevent damage to important excavations and reduce the exposure of miners to unsafe conditions. The Hybrid Stress Blasting Model is used to understand the explosive rock interaction and to illustrate and contrast good and bad blasting practices. In all cases, good supervision is required to continue safe mining according to the design.

Keywords: Blasting, safety, production, preconditioning, explosives, numerical modelling, drop raising, vibrations, and presplitting

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