ABSTRACT
Micro-mechanical modeling of medium dense Zbraslav sand was carried out with a special attention to the stress path effects demonstrated by proportional loading (PL) laboratory tests. Micro-mechanical model of Zbraslav sand has been generated and a new PFC2D procedure for numerical modeling of proportional loading tests with constant stress increment ratio developed. Using numerical biaxial tests and proportional loading tests the micro-properties of the synthetic material were calibrated in order to match the macro-scale response of the physical material. With regards to strength parameters, the calibration procedure revealed that some methodical aspects (e.g. velocity of loading platens) could considerably influence the peak strength of the synthetic sand. With regards to deformability, the influence of stress path direction changes on the deformational response of the synthetic sand has been proved, which is in good agreement with the laboratory test results. Solutions, results and some problems met are presented in the paper.
