Lightweight Cemented Soils: A First Attempt to Link Multi-Scale Experimental Observations and Thermodynamics-Based Constitutive Modelling

Abstract This paper proposes a first attempt to formulate a constitutive model for Lightweight - Cemented Soils (LWCS). The formulation, developed in the framework of Thermodynamics with Internal Variables, relies on a proper choice of the key internal variable capable of accounting for the macroscopic mechanical effects of the peculiar microstructure of this artificial material. The model is formulated based on the results of an experimental investigation on the mechanical response of LWCS specimens carried out under triaxial loading paths complemented by in-situ x-ray microtomography. Foam-induced porosity is considered as the only internal variable controlling the evolution of the microstructure, whereas the cemented matrix is modelled as an elastic perfectly plastic material. The predictive capability of the model is illustrated with reference to a series of numerical simulations of laboratory tests.