Modelling of creep effect on a healed crack in cementitious materials

Abstract

Self-healing of cracks by continuous hydration of unhydrated cement particles provide an improvement of mechanical properties for cementitious materials. Recent studies indicate that concrete specimens subjected to a sustained mechanical load lead to a variability of the mechanical properties recovery during self-healing. In fact, the presence of sustained mechanical load inset the creep deformations of concrete. In this paper, a numerical model based on the coupling of the microstructural hydration code CemPP and the finite element code Cast3M was performed to describe the mechanism of creep for healed structures. Numerical simulations have been carried out to determine the mechanical regains of cement paste cracked at 48 hours and then subjected to ongoing hydration process. After this first step, the viscoelastic creep behavior was investigated by applying a tensile creep load equal to 40% of tensile strength for each healed microstructure.