Construction of elastic viscoplastic constitutive model and settlement control of over-consolidated soil using finite element software ABAQUS

摘要

To study the settlement process of high-filled embankment before and after construction, an elastic viscoplastic constitutive model of over-consolidated soil is designed based on finite element analysis. The model is used to predict the settlement of subgrade before and after construction. First, the lower load surface is used as the reference yield surface of strain rate. Based on the principle of relative over stress, two rate sensitive parameters are established through the measurement of triaxial compression test with different strain rates. Second, the relative over stress function, stress function, and dynamic yield criterion function are established. Finally, two kinds of over-consolidated soils with over-consolidation ratios of 16 and 8 are tested for triaxial shear creep, and the finite element software is used for simulation analysis. The results show that the ultimate axial strain decreases with the decrease of deviatoric stress. When the creep time exceeds 3000min, the model has good prediction effect. The finite element calculation results of different backfill layers in inversion parameters show that the maximum settlement layer of high-filled embankment may not occur at the top or bottom, so attention should be paid in the construction process of high-filled embankment. This exploration provides a reference for the study of long-term deformation and strength of high-filled embankment.