Abstract: The study of cone penetration process has been a hot topic in the geotechnical engineering, and its results are mainly used to predict the strength of granular soils. In cone penetration process, the strain softening, and strain rate effect of the granular soil have a significant impact on its strength. It is difficult to describe the influence on the penetration results through theoretical methods, instead, numerical methods can well simulate the cone in the process of penetration. To evaluate the influence of the strain softening and strain rate effects on the penetration results, the subprogram of the soft soil constitutive model was compiled by using the re-development platform provided by ABAQUS. The soil constitutive model is applied to the numerical model calculation throughout the subprogram interface VUSDFLD, and the subprogram interface form and subprogram activation method are demonstrated. The Coupled Eulerian-Lagrangian method was used to simulate the cone penetration process. Firstly, the mesh sensitivity analysis of the model is carried out, and it is concluded that when the mesh density is less than 0.2mm, the influence on results is negligible; secondly, the numerical simulation results are compared with previous experiments and numerical cases, and the results show that the penetration depth and the penetration velocity of the cone are in good agreement with previous studies, which indicating that the analysis can better simulate the motion characteristics of the cone during the cone penetration process. The results show that the re-development procedure can well simulation the application of the strain rate effect and the strain softening soil constitutive model in ABAQUS.

Key words: Numerical Simulation, Re-Development, VUSDFLD Subroutine, Strain-Rate Effects, Strain Softening