Thermo-chemo-mechanical behavior of alkali-activated slag materials - Focus on early-age

Abstract

International audienceThis study addresses the development of a modelling approach predicting the behavior of waste packages made with an alkali activated slag mortar. Durability of such structures is studied regarding the restriction of hydraulic binder's strains by the rigid inclusions and the wasteforms' container. The current work focuses on early-age behavior. First, the evolution of material's mechanical properties and delayed strains (autogenous shrinkage and basic creep) are determined experimentally. Results show that equivalent time approach should be used for simulations to address correctly the time-dependent evolution of mechanical parameters, rather than an approach based on hydration degree (determined by calorimetry). For basic creep, the use of an aging dashpot seems to be sufficient. Then, finite element calculations at meso-scale are performed to determine homogenized properties of binderwaste assembly. Results are used for macro-scale simulations