Modification of the Kuz-Ram model using response surface methodology to optimise blast fragmentation

Saubi, Onalethata; Suglo, Raymond S.

doi:10.22059/ijmge.2026.400194.595289

Modification of the Kuz-Ram model using response surface methodology to optimise blast fragmentation

Document Type : Research Paper

Authors

Department of Mining Engineering, Botswana International University of Science and Technology, Palapye, Botswana.

10.22059/ijmge.2026.400194.595289

Abstract

Predicting and optimising blast-induced rock fragmentation is essential for improving downstream mining operations such as loading, hauling, and comminution. The widely used Kuz-Ram model often requires heuristic calibration of the rock factor, which limits its predictive accuracy in heterogeneous rock masses. This study introduces a modified Kuz-Ram model that integrates response surface methodology (RSM) to refine the rock factor estimation based on the blastability index (BI). A dataset of 80 production blasts from Orapa Diamond Mine, Botswana, incorporating four input parameters, powder factor, charge, rock factor, and blastability index was analysed. The RSM-modified model demonstrated a 12.2% improvement in prediction accuracy compared to the traditional Kuz-Ram model, achieving an R² of 0.579, with RMSE and MAE reduced to 5.71 and 3.07 respectively. The approach preserves the empirical simplicity of Kuz-Ram while explicitly modelling nonlinear parameter interactions, offering a transparent yet robust tool for blast design. This method is practical for mines requiring rapid calibration to site-specific geological conditions and can be extended to include additional parameters, such as delay timing, in future work.

Keywords

Main Subjects

Mineral Exploitation

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