Applications of Finite/Discrete Element Modeling to Rock Engineering Problems

Abstract

In this paper, the authors review recent applications of an integrated numerical modeling approach based on the analysis of the mechanical behavior of discrete systems. The numerical analysis includes both a more realistic representation of fracture networks and the simulation of rock mass behavior as a combination of failure through intact rock and displacement/rotation along predefined discontinuities. Selected examples are presented with respect to a variety of engineering problems, including shear testing, failure of hard-rock pillars, slope stability, and block/panel cave mining. The results clearly illustrate the importance of including natural jointing to better capture rock mass behavior in response to loading and unloading. Particular emphasis is given to modeling cave development and surface subsidence, and the proposed numerical method is shown to capture fully the complex rock mass response to caving associated with multi lift extraction. Whereas the use of relatively complex numerical models is progressively becoming widespread in industry, this paper also reviews how numerical simulations of rock mass behavior strongly depends on the geological assumptions used to build the underlying discrete fracture network model and the mechanical properties of the natural discontinuities. Accordingly, a correct balance among engineering judgment, field characterization, and numerical modeling should always be maintained to reduce model uncertainty.