Influence of the porosity gradient in cement paste matrix on the mechanical behavior of mortar

This paper is devoted to the study of the influence of the microstructure of mortar on its mechanical behavior. For this purpose, mechanical tests have been carried out on mortars and a mathematical model, the (n + 1)-phase model, has been used to take into account three variable parameters of the microstructure of mortar (the thickness of the interfacial transition zone, the porosity gradient in the cement paste matrix and the nature of the constituents of the Interfacial Transition Zone) for some given parameters (volume fraction of aggregates, porosity of the mortar and mechanical behavior of the aggregates and the cement paste). By fitting some measured moduli to the model predictions, we can estimate in a non-destructive manner, the possible distribution of porosity within the Interfacial Transition Zone. Our results provide information on the data such micromechanical models can deal with in order to predict the elastic behavior of mortars. (C) 2010 Elsevier Ltd. All rights reserved.