An Advanced Critical State Constitutive Model for Overconsolidated Structured Soils

Abstract

This paper presents a constitutive model for simulating the stress–strain behavior of overconsolidated structured soils. The model extends the scope of a previous 10-parameter constitutive model proposed by the authors for structured soils. It uses a variable normal compression index dependent on the degree of structure to simulate structure degradation during loading. The model also introduces the concept of subloading plasticity to prevent the peak shear strength of structured soils from being overestimated in the overconsolidated state. The performance of the proposed model in describing the mechanical behavior of structured soils with different initial overconsolidation ratios is assessed. The proposed model is verified using the experimental data available in the literature for both naturally and artificially structured soils under compression and shearing conditions. The results indicate that the proposed model simulates the mechanical response of structured soils reasonably well in both normally consolidated and overconsolidated conditions.