At early-age, hydration of cement leads to a reduction of volume (caused by the Le Chatelier contraction) which induces autogeneous shrinkage. Besides, hydration is an exothermic reaction and an increase of temperature occurs (followed by a decrease). As autogeneous shrinkage…
At early-age, hydration of cement leads to a reduction of volume (caused by the Le Chatelier contraction) which induces autogeneous shrinkage. Besides, hydration is an exothermic reaction and an increase of temperature occurs (followed by a decrease). As autogeneous shrinkage arises only in cement paste and as coefficient of thermal expansion may be different between cement paste and aggregates, strains incompatibilities lead to an internal self-equilibrated state of stress. Depending especially on the concrete mix, initial cracking may occur at the cement paste scale leading to a modification of the global concrete behavior. In this contribution, an analysis of the internal stresses is performed on a mesoscopic mesh by finite element calculations taking into account hydration, autogeneous and thermal shrinkage, basic creep and cracking. Influence of creep strains and mesoscopic representation are studied showing that, for an ordinary concrete, hydration lead to a reduction of “elastic” stiffness and tensile strength even if creep is taken into account.