Large hole blasting

Langzeit-Teste =long time test shelf life tests 114 285 large hole blasting 195 LASL = Los Alamos, National Scientific Laboratory (USA)... 

Sanshokitoruoru = TNT (Japan) 339 Sauerstofftrager = oxidizer 241 Sauerstoffwert Sauerstoffbilanz 242 sautage a gran trou = large hole blasting 195... 

That part of a drilled blast hole that remains when the force of the explosion does not break the rock completely to the bottom of the hole (-> Large Hole Blasting). 

Coyote blasting has now been almost completely displaced by -> Large Hole Blasting, because the spaces accommodating the explosive can be produced more rationally in this way. 

The economic advantage of large-hole blasting, and therefore its widespread use, are due to the fact that the operations of "drilling" and "loading of the rock pile" can be carried out quite independently of each other. 

Fig.3 Cumulative distribution curve for rock pile produced by large-hole blasting (linear scales on both axes)...

There is a whole range of possible variations in large-hole blasting practice, from single-row and multiple-row blasting with or without toe holes to so-called surface blasting. 

With large-hole blasting, the maximum of the noise emitted is in the low frequency range, between about 50 and 500 Hz. On the other hand, secondary blasting often produces a very objectionable bang with its maximum in the strongly audible frequency range of between about 500 and 2000 Hz (see Funke, 1978). 

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