Hydration induced meso-stresses in concrete and their consequences on the cyclic behavior

La Borderie, C., Mathallah, M., N'Guyen, T.D., Briffaut, M., Benboudjema, F. & Torrenti, J. (2010), "Hydration induced meso-stresses in concrete and their consequences on the cyclic behavior", In Euro Mediterranean Symposium On Advances in Geomaterial and Structures. Djerba, Tunisia. 10-12 May 2010.

The hydration process of concrete involves heating, progressive hardening, shrinkage. It is well known that this process can create cracking of large structures, but, depending on the concrete mixture used, leaves usually small specimens elastic. In the case of small specimens, strain mismatch between paste and aggregates generates autogenous stresses in concrete. Even if this state of stress does not affect the elasticity properties of concrete it modifies the initial conditions of any concrete structures. We propose to compute the initial state of stress in concrete at the mesoscopic level and show that this state of stress is at the origin of a part of the inelastic strains that go with damage and the so called “crack closure stress” under cyclic loading.