Application of Finite Element Method for Simulation of Rock Mass Caving Processes in Block Caving Method

Document Type : Original Article

Authors

School of Mining Engineering, College of Engineering, University of Tehran, Tehran, Iran

Abstract

Determining the caving height in the block caving method requires considering a suitable caving criterion discussed in this study. The comparison between different caving criteria and choosing appropriate caving criteria for use in rock mass cavability study is the main idea of this study, which has not been investigated in previous studies. In this paper,  through FEM (Finite Element Method) software, the height of the caving area in different undercutting stages was calculated using the criteria of displacement and shear and tensile failure. The results revealed that when using shear and tensile failure, the height of the caving was almost four times higher than the displacement criterion. The height of the caving reaches 249.15 m in this case. However, it is 59 and 107 m considering the allowable displacement and strain criteria, respectively. According to empirical methods, the caving propagated to the highest block height. Thus, the shear and tensile failure criteria predict the caving height better than the displacement criteria.

Keywords

Main Subjects


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