Hybrid Stress Blast Model

Since 2001, Itasca has been a member of the Hybrid Stress Blast Model (HSBM) project with the goal of developing a numerical model of the rock blasting process. The software created by Itasca, called Blo-Up, uses a unique combination of continuous and discontinuous numerical methods to represent the key processes occurring during blasting.

Sample output from Blo-Up showing the predicted muckpile shape resulting from a 20 hole bench blast.

Briefly, Blo-Up is a three-component coupled model of rock blasting; a coupled modeling approach was chosen because no single numerical technique was found to adequately describe all the physical phenomena occurring during blasting. The three components are (i) a continuum geomechanics model for the early-time detonation and near-field crushing; (ii) a brittle discrete element model for stress wave propagation, fracturing and burden movement; and (iii) a gas product model for burden acceleration by gas expansion, fracture flow and atmospheric venting.

Itasca presently is involved in the HSBM Validation Project, which seeks to prove the quality of Blo-Up model predictions in real world blasting. Field-scale bench and underground blasting tests currently are being used to validate and improve the model. The goal of the software is to provide blasting engineers a high-quality predictive model of blast outcomes. Application areas include mine to mill optimization, grade movement predictions and pit wall damage studies.

Read more on the HSBM project:


Sellers, E., J. Furtney, I. Onederra and G. Chitombo. (2012) “Improved Understanding of Explosive – Rock Interactions Using the Hybrid Stress Blasting Model,” in SHIRMS 2012 (Proceedings of the Second Southern Hemisphere International Rock Mechanics Symposium, South Africa, May, 2012).

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