ABSTRACT
Chapter 13 discusses the use of blasting to excavate rock. The mechanism of rock fracture by explosives is described, and how this can be used to design blasts and control blast damage. Production blasting methods are discussed including blast hole patterns, detonation sequences and appropriate explosive loads, expressed as the ‘powder factor’. Final wall blasting is described, including cushion blasting and pre-shearing design, with respect to drill hole patterns and explosive loads. Finally, control of blast damage to nearby structures due to ground vibrations, noise and flyrock is discussed; allowable thresholds for ground vibrations are listed.
