Automating the Calibration of Flat-Jointed Bonded Particle Model Microproperties for the Rewan Sandstone Case Study

Abstract The flat joint contact model (FJM) provides significant improvements over its predecessors, the parallel bond and models, for bonded particle modelling of rocks due to unique microstructure that allows reproduction macroscopic compressive–tensile strength ratio, σ c /|σ t | ; internal friction angle, ϕ Hoek–Brown constant, m i . However, microproperty calibration process is tedious time-consuming perform manually various interdependencies exist in FJM. Previous attempts at automating have typically utilised advanced statistical methods, such as artificial neural networks, but they not yet been widely applied FJM a representative range confining stresses calculation In this study, new method proposed based on numerical root-finding algorithm specific sequencing. Rewan Sandstone case study with similar natural porosity 2D packed low initial mean stress. resulting microproperties are shown reproduce both target laboratory properties realistic damage evolution, including normalised crack initiation stress 0.46 0.83 coinciding reversal axial stress–volumetric strain curve an unconfined compression test simulation. It also demonstrated absolute change instantaneous lateral–axial ratio (Poisson’s linear-elastic phase) reasonable proxy acoustic emissions which may be measured laboratory.