A calibration method of discrete element contact model parameters for bulk materials based on experimental design method

This study proposes a method to address the issues of large amount of calculation and low efficiency in the calibration of discrete element method (DEM) contact model parameters for rockfill, which is based on the experimental design method. Plackett-Burman design method was used to analyze the significance of each contact model parameter to the macro-mechanical parameters. Second-order response surface regression models were developed to analyze the relationship between macro-mechanical parameters and contact model parameters that have significant impact on them. The contact model parameters in the rockfill DEM were calibrated using a multi-objective optimization method based on laboratory triaxial tests. The calibrated parameters were then used to simulate discrete element triaxial tests of the rockfill under varying pressure conditions. The study demonstrates that calibrated parameters can accurately predict the macroscopic behavior of rockfill under different confining pressures. Additionally, the calibration method has good applicability and effectiveness.