Abstract
The overall behaviour of rock mass is effectively controlled by the micro properties of its constituent particles and the bonds between the particles. Unfortunately, the micro-scale properties are challenging to measure with standard laboratory tests. This study investigated the influence of these micro-scale bonding properties on typical parameters. This research provided a parametric study of four bond parameters: 1) normal to shear stress ratio (kratio); 2) tensile strength (fj_ten); 3) effective modulus (emod); 4) cohesion (fj_coh). These selected parameters should be adjusted and calibrated first to match lab tests. The procedure for generating material for flat-joint models should start with adjusting the four bond parameters; 1) kratio to synchronise the material's Poisson's ratio; 2) fj_ten to synchronise the material's tensile strength; 3) emod to synchronise the material's Young's modulus; 4) fj_coh to synchronise the material's compressive strength. This procedure was most effective because the last parameter's calibration does not affect the previously calibrated parameters. Based on the results, a systematic procedure was developed to facilitate easy calibration of PFC2D models to match laboratory testing results.