Evaluation of Kiruna mine drifting data using the NIOSH design approach.
Hustrulid WA; Iverson SR
Rock Fragmentation by Blasting: Proceedings of the 9th International Symposium on Rock Fragmentation by Blasting, FRAGBLAST 9, September 13-17, 2009, Granada, Spain. Sanchidrián JA, ed., Boca Raton, FL: CRC Press, 2010 Jan; :497-506
The National Institute of Occupational Safety and Health (NIOSH) has developed a new drift round blast design approach as part of a comprehensive program to improve underground mine safety through the introduction and implementation of better blasting practices in drifting. The key to better perimeter control blasting has been found to lie in the proper design of the buffer/helper row. Although in retrospect this finding is not particularly surprising, it goes against conventional wisdom in which special design efforts are spent on perimeter hole charge, spacing and burden design and rather little on the buffer row design. The paper begins with a brief introduction to the NIOSH buffer row design approach. This is followed by the presentation of a comprehensive set of data from 9 different drift rounds in iron ore and 3 rounds in waste rock in which the buffer row design remained constant but significantly different wall control designs were employed. Because the buffer row design was well-chosen, the extent of the over-break is shown to be essentially independent of perimeter charge concentration over a very wide range of values. This finding has a significant impact on future drift design concepts. The paper concludes with some ideas regarding future developments.
Mining-industry; Blasting-agents; Underground-mining; Rock-mechanics; Work-practices; Controlled-environment; Control-methods; Control-systems; Control-technology; Environmental-control; Environmental-control-equipment; Environmental-technology; Explosions; Safety-engineering; Safety-practices; Accident-prevention; Electrical-charge
W. A. Hustrulid, NIOSH Spokane Research Laboratory, Spokane, WA, United States
Rock Fragmentation by Blasting: Proceedings of the 9th International Symposium on Rock Fragmentation by Blasting, FRAGBLAST 9, September 13-17, 2009, Granada, Spain