A micromechanical framework for thermo-elastic properties of multiphase cementitious composites with different saturation

Abstract

• A micromechanical framework is devised for thermo-elastic properties of CC . • The framework accurately predicts the thermo-elastic properties of CC. • Increasing saturation degree improves the thermo-elastic properties of CC. • CTE monotonically increases with the increase of porosity. Abstract: Understanding of the thermo-elastic properties of cementitious composites (CC) with different saturation degrees is of great importance for the design of CC durability in various hydraulic environments. This work devises a generic micromechanical framework to predict the effective thermo-elastic properties involving the elastic modulus, thermal conductivity, and coefficient of thermal expansion (CTE) of multiphase CC with different saturation degrees, composed of spheroidal aggregates and their surrounding interfacial transition zones (ITZs), water-pores, air-pores and homogeneous bulk paste at a microscopic scale. Comparisons against experimental measurements and theoretical bounds suggest that the micromechanical framework is a reliable means to accurately estimate the effective thermo-elastic properties of multiphase CC under different saturation conditions. The proposed model sheds light on the quantitative effects of saturation degree, porosity, pore shape, and aggregate shape and volume fraction, and ITZ thickness on the thermo-elastic properties of CC, which can provide insights for the design of “tailor-to-demand” thermo-elasticity performance of CC.