Study on mesoscopic numerical parameters in numerical tests of sand-pebble geology

To study the influence of the meso-mechanical parameters of sand-pebble on the macro-mechanical properties, the numerical simulation method of discrete element method and the sand-pebble numerical triaxial test are used, a test method for elliptical particles is proposed, and the sensitivity analysis of the meso-mechanical parameters of sand-pebble is performed. The results show that the effective modulus of the particles has a significant effect on the macroscopic elastic modulus of the material, and the increase in the macroscopic elastic modulus of the material has an approximately linear relationship with the increase in the effective modulus. The effect of the particle stiffness ratio on the macro-mechanical properties of the material is insignificant. The increase in the friction coefficient is roughly linearly related to the increase in the peak stress. The increase in the interparticle porosity has a negative correlation with the decrease in the peak stress, and the particle diameter ratio affects both the number of particles produced and the peak stress. This paper provides a reference for the theoretical basis for subsequent research on the physical and mechanical characteristics of sand-pebble geology.