Blastability of rocks under permafrost conditions
For normal working of the bottom the linear dimensions of the borehole grid in frozen rocks should be reduced 13% and the explosive ratio increased 28% compared to the same rocks in a normal (thawed) state.
When reissuing the standards the tables of explosive consumption should be supple-mented by the explosive ratios for frozen rocks according to Table 1 of this article.
The adverse effect of permafrost on the blastability of rocks is observed not only with respect to working the bottom but also to crushing of the rock mass. Therefore, in frozen large-block rocks producing an increased yield of oversize, the required explosive ratio can substantially exceed the value needed for working the bottom. The value of the explosive ratio for the required crushing of the rock should be established by experimental explosions for the specific mining conditions.
KeywordsAdverse Effect Explosive Energy Source Rock Mass Power Generation
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- 1.Technical Regulations for Conducting Blasting Works in Power Construction [in Russian], Énergiya, Moscow (1972).Google Scholar
- 2.Standard Handbook on Boring and Blasting Works [in Russian], Nedra, Moscow (1975).Google Scholar
- 3.E. I. Shifrin, “Use of the full-scale template method for determining the granulometric composition of rock in blasted-rock piles,” in: Abstracts information on Progressive Experience (Minmontazhspetsstroi SSSR), Series V, Special Works in Industrial Construction [in Russian], No. 1 (103) (1975).Google Scholar
- 4.V. K. Rubtsov and S. A. Davydov, Multiple-Row Blasting [in Russian], Nedra, Moscow (1965).Google Scholar
- 5.B. N. Kutuzov, N. I. Pomesh, and V. F. Pluzhnikov, “Classification of rocks according to blastability for quarries,” Gornyi Zh., No. 2 (1979).Google Scholar