Numerical Modelling of Slide-Head-Toppling Failure using FEM and DEM Methods

Sarfaraz, H.; Bahrami, A.R.; Samani, R.

doi:10.22044/jme.2022.11698.2159

Document Type : Original Research Paper

Authors

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

https://doi.org/10.22044/jme.2022.11698.2159

Abstract

A common instability in the rock slopes is a toppling failure. If this type of slope failure occurs due to another kind of failure, it is considered as the secondary toppling failure. A type of secondary toppling failure is the slide-head-toppling failure. In this instability, the upper portion of the slope is toppled, and the pressure caused by the overturning of rock blocks leads to a semi-circular sliding in the soil mass at the slope toe. This instability is examined through the theoretical analysis and physical modelling. Firstly, the failure mechanism mentioned above is described. Next, the slide-head-toppling failure is studied through seven numerical simulations. The Phase2 and UDEC softwares, as the finite element and distinct element methods, respectively, are used in this work. Different kinds of slide-head-toppling failure are modelled such as the blocky, block-flexural, and flexural toppling failures. The numerical modelling results are compared with the existing physical tests and theoretical approaches. This comparison illustrates that the safety factor is underestimated due to the plane strain supposition in numerical modelling. However, the side-friction in the physical models has violated this assumption. The results obtained demonstrate that the distinct element method has an acceptable accuracy compared to the finite element method. Thus this numerical code can be used in order to examine the mentioned failure.

Keywords

20.1001.1.22518592.2022.13.1.19.1

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Numerical Modelling of Slide-Head-Toppling Failure using FEM and DEM Methods

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References

Volume 13, Issue 1January 2022Pages 269-280

Volume 13, Issue 1
January 2022
Pages 269-280