Numerical Modeling of Rock Slopes with a Potential of Block-Flexural Toppling Failure

One of the most important instabilities of rock slopes is toppling failure. Among the types of toppling failure, block-flexural failures are a more common instability, which occurs in nature. In this failure, some rock blocks break due to tensile stresses, and some overturn under their weights, and next to all of them topple together. In 2015, the physical and theoretical modeling of this failure has been studied by Amini et al. Due to the complexity of this failure mechanism, no appropriate numerical model has been proposed so far. In this research work, first, a literature review of the toppling failure is summarized. Then using the UDEC software, as a distinct element method (DEM), the experimental models are analyzed numerically, and the Voronoi joint model is applied to simulate the failure. The results of the numerical simulations are compared with the outcomes of the physical models and analytical solutions. This comparison illustrates that the numerical modeling has a good agreement with the corresponding experimental tests and theoretical approaches. Also the results obtained show that although the mechanism of block-flexural toppling failure is complicated, the numerical code is well-capable of analyzing this failure.