Effect of pore shape on the thermal conductivity of partially saturated cement-based porous composites

Increasing demands of new cement-based porous composites for thermal insulation required by sustainable development are crying out for clarifying the key factors affecting their thermal properties. In this study, we focused on the effect of pore shape, a factor that was often slighted or ignored before, on the thermal conductivity of composite materials. We established a predicting model for a simple twophase inclusion-matrix system based on effective medium and mean-field theories. The model can be easily extended to assess the effective thermal conductivity of multi-phase and multi-scale composites. The generalized model involves both homogenization schemes and material structures including the shapes and orientations of inclusions. We showed that the shapes of inclusions affect the effective thermal conductivity of composites significantly. The established model were used to predict the thermal conductivities of cracked ordinary concrete and partially saturated autoclaved aerated concrete reported in the literature with in-depth discussion. (C) 2017 Elsevier Ltd. All rights reserved.