JOURNAL OF ROCK MECHANICS

JOURNAL OF ROCK MECHANICS

Numerical Investigation of Rock Mass and Explosive Properties on Blast Damage in Rock Slopes

Document Type : Original Article

Authors
Ali Haghnejad 1
Kaveh Ahangari 1
Parvizz Maarefvand 2
Kamran Goshtasbi 3
1 Department of Mining Engineering, Faculty of Engineering and Technology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
2 Faculty of Mining Engineering, Amir Kabir University of Technology (Tehran Polytechnic), Tehran, Iran.
3 Faculty of Engineering, Tarbiat Modares University, Tehran, Iran.
Abstract
Explosion leads to disturbance in the rock mass and its damage. In this study, an attempt has been made to evaluate the explosion damage caused by two explosives, Anfo and Ammolite, using 3D discrete element numerical modeling of two almost similar slopes. In this regard, 4 different rock mass properties and two discontinuities with opposite and consistent extensions to the slope face were used in the modeling. Explosion damage was qualitatively investigated by the possible fracture zones of the 3DEC software and quantitatively evaluated using the maximum particle velocity values ​​recorded during the explosions. Based on this, it was determined that geological discontinuities control the plastic flow of tensile and shear fractures. Of course, discontinuities with an orientation consistent with the slope face play a more effective role in reducing explosion damage. With increasing rock mass strength and with discontinuities consistent with the slope face, the impact of an Ammolite explosion from 10 meters from the pit opening is less than that of Anfo explosion. Considering the impact of discontinuities on damage control, the use of artificial discontinuities, such as those developed in pre-cracking explosions, would be a suitable method to reduce damage and prevent instability in slopes.
Keywords
Rock Mass Discontinuity
Blast Damage
Rock Mass Properties
ANFO
Emulsion
3DEC
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JOURNAL OF ROCK MECHANICS
Volume 1, Issue 4
Winter 2016
Pages 11-22