TECHNICAL NOTE Effect of Loading Rate on Sand Pile Failure: 2D DEM Simulation Manoj Khanal . Marc Elmouttie . Brett Poulsen . Andrew Olsson . Deepak Adhikary Received: 4 July 2016 / Accepted: 19 December 2016 Ó Springer International Publishing Switzerland 2016 Abstract Discrete element method (DEM) is a widely used simulation tool to model physical behaviour of granular materials. In this study 2D DEM simulation has been used to simulate the failure of a sand pile loaded at the crest. The model has been calibrated and validated using experimental force- displacement behaviour, angle of repose and particle velocity profile. The effects of numerical loading rates on simulation results have been investigated. The calibrated DEM model showed that the selection of loading rate is crucial in simulating particle assembly behaviour. In the quasi-static state a small change in loading rate does not change the force-displacement behaviour of the model. However, the system becomes unstable and force-displacement behaviour of the granular assembly diverges from the quasi-static state when the loading rate is higher than the quasi-static loading rate. Keywords Sand pile failure Á DEM Á Loading rate Á Grains Á PFC 1 Introduction The paper describes a numerical simulation designed to capture the failure of a sand pile at the natural angle of repose and estimate the force-displacement beha- viour of the sand pile while loaded from the crest. Discrete element method (DEM) is a widely used simulation tool to model physical behaviour of granular materials (Cleary and Sawley 2002; Khanal et al. 2005, 2007, 2008b; Schubert et al. 2005; Antonyuk et al. 2006, 2010; Khanal and Morrison 2008, 2009; Khanal and Tomas 2008, 2009; Arslan et al. 2009; Grima and Wypych 2010; Le Bouteiller and Naaim 2010; Markauskas and Kac ˇianauskas 2010; Brosh et al. 2011; Khanal 2013; Mu ¨ller et al. 2013; Khanal and Jayasundara 2014; Guo and Curtis 2015) including free flow of particles (Cleary and Sawley 2002; Khanal and Morrison 2008, 2009; Khanal and Jayasundara 2014; Guo and Curtis 2015) and breakage of composite particles (Khanal et al. 2005, 2007, 2008b; Schubert et al. 2005; Antonyuk et al. 2006, 2010; Arslan et al. 2009; Khanal and Tomas 2009; Le Bouteiller and Naaim 2010; Li and Cheng 2015). Depending on applications, in 2D models circular and non circular and in 3D models spherical and non-spherical particles can be used to M. Khanal (&) Á M. Elmouttie Á B. Poulsen Á D. Adhikary Commonwealth Scientific and Industrial Research Organization (CSIRO) Energy, 1 Technology Court, Pullenvale, QLD 4069, Australia e-mail: Manoj.Khanal@csiro.au A. Olsson Commonwealth Scientific and Industrial Research Organization (CSIRO) Minerals, 1 Technology Court, Pullenvale, QLD 4069, Australia 123 Geotech Geol Eng DOI 10.1007/s10706-016-0142-3