Effect of porosity on the thermal expansion coefficient: A discussion of the paper ‘Effects of mineral admixtures on the thermal expansion properties of hardened cement paste’ by Z.H. Shui, R. Zhang, W. Chen, D. Xuan, Constr. Build. Mater. 24 (9) (2010) 1

A discussion is presented on the effect of porosity change on the thermal expansion coefficient of porous materials. It is shown that both drained and undrained thermal expansion coefficients normally increase with porosity increase. Consequently the reduction of the thermal expansion coefficient with the porosity increase, as obtained in the experimental results of Shui et al. [1], cannot be considered as a general trend for the behaviour of porous materials.