Uniaxial compression tests of prismatic Dionysos marble specimens are simulated numerically using the distinct element code PFC2D. Two kinds of models are prepared for the current study: Bonded Particles Models (BPMs) and Grain Based Models (GBMs). 100 BPMs and 110 GBMs, the latter consisting of deformable, un-breakable polygonal grains cemented on their adjoining sides, are prepared. The PFC2D parameters considered as uniform random variables within a preselected range and the micro-parameters sets are obtained through latin hypercube sampling. The models are subjected to numerical uniaxial compression tests and the relation between the PFC2D parameters and the macro-mechanical response of the synthetic rock is examined. Diagrams relating the PFC2D parameters and the synthetic rock properties are presented. These diagrams are then used in order to select the optimum sets of PFC2D parameters to be used for the Dionysos marble simulations. The numerically obtained stress-strain diagrams are compared to those measured experimentally. Further, the evolution of bonds breakage during the simulation is compared to the rock acoustic emission during loading. The simulation results demon-strate that both the macro-mechanical response and the failure process can be modeled using the BPMs and the GBMs. Some differences between the numerical results and the macroscopic marble behavior are discussed.
The bonded-particles model BPM (Potyondy & Cundal 2004) has been extensively used over the past decade to simulate the mechanical behaviour and fracture of intact rock under a variety of loading configurations. In the BPM, the intact rock is repre-sented by a dense packing of rigid spheres or disks bonded together at their contacts. The model is implemented in the Particle Flow Code PFC (Itasca 2009) which em-ploys the Distinct Element Method (Cundal 1971, Cundall & Strack 1979). The formulation of the BPM in PFC is described in detail in Potynondy & Cundal (2004).
