Enhancing Discrete Element Model Accuracy for Lunar Soil: Calibration and Validation of Mesoscopic Parameters

This study introduces a novel discrete element model calibration methodology incorporating particle shape and the van der Waals forces between particles. The effect of mesoscopic parameters on peak stress and failure point are systematically calibrated in the model by triaxial compression stress-strain curves. The results show that six meso-parameters have significant impact on the mechanical response of the model, including effective modulus, rolling friction coefficient, normal-to-shear stiffness ratio, damping coefficient, maximum attractive force and attraction range. The model accurately simulates complex mechanical behavior in both loose, dense lunar soils and soil-tool interaction.