UH Model for Granular Soils

A constitutive model is presented to describe the mechanical behaviors of granular soils. A S-shaped normal compression line (NCL) is first expressed by a simple equation. Subsequently, a state parameter (ξ) is defined to quantify the current state of granular soils, and a unified hardening parameter (H) that is a function of the state parameter (ξ) is developed to govern the hardening process of the drop-shaped yield surface. A constitutive model for granular soils is proposed by combining with flow rule. Finally, the comparison between the predictions and the test results of Cambria sand indicates that the model is able to describe the mechanical behaviors of granular soils in a large stress range.