Physical and theoretical modeling of rock slopes against block-flexure toppling failure

Document Type : Research Paper


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

2 Msc Student, Department of Mining Engineering, University of Kashan, Iran

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


Block-flexure is the most common mode of toppling failure in natural and excavated rock slopes. In such failure, some rock blocks break due to tensile stresses and some overturn under their own weights and then all of them topple together. In this paper, first, a brief review of previous studies on toppling failures is presented. Then, the physical and mechanical properties of experimental modeling materials are summarized. Next, the physical modeling results of rock slopes with the potential of block-flexural toppling failures are explained and a new analytical solution is proposed for the stability analysis of such slopes. The results of this method are compared with the outcomes of the experiments. The comparative studies show that the proposed analytical approach is appropriate for the stability analysis of rock slopes against block-flexure toppling failure. Finally, a real case study is used for the practical verification of the suggested method.


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