Testing and Constitutive Modeling of Lime-Stabilized Collapsible Loess. II: Modeling and Validations

Abstract

Assessing the hydromechanical behavior of collapsible soils is always a challenging topic in an unsaturated soil mechanics context. Although numerous efforts have been made thus far to establish frameworks for explaining the stress–strain behavior of collapsible soils, many of them are developed based on the results from conventional tests without controlling or measuring the unsaturated state variables. Furthermore, modeling the hydromechanical behavior of chemical-stabilized collapsible soils has been rarely studied. To establish a constitutive model for predicting the behavior of a lime-stabilized collapsible soil, the results obtained from filter paper and unsaturated odometer tests on a lime-treated loessial soil (which are presented in a companion paper) have been analyzed by considering the effective stress approach for unsaturated soils. An empirical model for explaining the load-collapse behavior of lime-stabilized tested soil is presented. Moreover, by implementing the disturbed state concept (DSC) method, a coupled semiempirical hydromechanical model is developed to predict the disturbance level and calculate the soil strain due to application of the vertical stress in Ko condition. Both presented models in this research are introduced as functions of two important governing state and material variables, namely matric suction and lime content. Results show excellent conformance between the laboratory test results and model predictions.