Numerical Modelling of Rock Fracture Using Polygonal Finite Elements
Research output: Other conference contribution › Paper, poster or abstract › Scientific
|Publication status||Published - 2018|
|Event||The 44th Israel Symposium on Computational Mechanics - Ben Gurion University, Beer Sheva, Israel|
Duration: 22 Mar 2018 → …
|Conference||The 44th Israel Symposium on Computational Mechanics|
|Period||22/03/18 → …|
In this paper, we present some results on a research project aiming at the simulation of rock fracture with a mesoscopic model based on polygonal finite elements. As the mineral texture of many rocks is polygonal, the polygonal finite element method is a natural choice. Here, the rock meso-structure is described as a Voronoi diagram where the Voronoi cells are the physical polygonal finite elements. Then, the minerals constituting the rock are represented by random clusters of polygonal ﬁnite elements.
In order to account for rock fracture, the meso-scopic rock material description is equipped with a damage-viscoplasticity model based on the Hoek-Brown criterion. Due to the asymmetry of the tension and compression behavior of rocks, separate scalar damage variables, driven by viscoplastic strain, are employed in tension and compression. The final aim is to study problems with transient impact loadings, e.g. percussive drilling. For this reason, the system equations of motion are solved by explicit time marching.
In the numerical examples, the capabilities of the present rock material description are demonstrated. Namely, uniaxial tension and compression tests of a numerical rock sample are simulated under plane strain conditions. Finally, the dynamic Brazilian disc test simulations are carried out as a dynamic example. These simulations demonstrate that the present method can capture the salient features, including the stress-strain response and the failure modes, of typical rock behavior in these applications.