Effect of Distributed Spherical Air-Gaps on Performance of Emulsion Explosive

  • Vineeth BalakrishnanEmail author
  • Manoj Pradhan
  • P. Y. Dhekne
Original Contribution


The high density of emulsion explosives results in excessive consumption in weak-to-medium-strength rock mass. Reducing the explosive consumption is necessary for optimizing the overall blasting cost. The authors have developed a technique of reducing explosive consumption by using small spherical air-gaps. Laboratory experiments are conducted by measuring varying unconfined VOD for emulsion explosive cartridge induced with various percentages of spherical air-gaps. It is found that the VOD of emulsion explosives is falling from 4241 to 3654 m/s for cartridge with 0.20 voidages. The VOD is falling abruptly when the voidages are increased and resulting in uncertainty of detonation at 0.30 voidage. The findings of the study can assist the mine operators to judiciously reduce the consumption of explosives without compromising the explosive performance.


Velocity of detonation Distributed spherical air-gap blasting Emulsion explosive Explosives consumption reduction 



The authors acknowledge the management of M/S Special Blasts Limited, Raipur, India, for providing necessary facilities for conducting the experiments. The authors also acknowledge Director, NIT Raipur, India, for providing necessary funds for carrying out laboratory experiments.


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Copyright information

© The Institution of Engineers (India) 2019

Authors and Affiliations

  1. 1.Department of Mining EngineeringNational Institute of TechnologyRaipurIndia

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