Small scale in-rock precompression testing: Effects of delay timing
- ICI Explosives USA Inc., Denver, CO (United States)
Previous work has shown that testing of precompression effects conducted on a small scale under simulated field conditions in actual rock provides a reasonable model for the evaluation of explosives and initiators under the adverse conditions encountered in production blasting. Using this methodology can result in greater understanding of the phenomena as well as the ability to predict performance. This effort has been extended to evaluate various parameters not previously studied in a controlled fashion. The present paper describes the use of this technique to study the effects of delay timing on precompression effects. Intervals from 25 to 150 milliseconds are included in the study. Both VOD measurements and damage estimates are utilized in the evaluation. The results demonstrate that timing delay between holes is quite important in determining the overall effectiveness of a blasting program. In addition, a parallel study was conducted to evaluate the usefulness of a smaller laboratory scale testing regime in screening various approaches to reduce the effects of precompression. Results are presented which indicate the presence of definite correlations between the laboratory procedure and the rock tests. The use of both methods together is shown to provide the explosive formulator as well as the mining engineer with an important tool for obtaining improved results.
- OSTI ID:
- 398323
- Report Number(s):
- CONF-9401127-; TRN: IM9649%%531
- Resource Relation:
- Conference: 10. annual symposium on explosives and blasting research, Austin, TX (United States), 30 Jan 1994 - 30 Jan 1996; Other Information: PBD: 1994; Related Information: Is Part Of Proceedings of the tenth annual symposium on explosives and blasting research; PB: 313 p.
- Country of Publication:
- United States
- Language:
- English
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