Damage Localisation in Fresh Cement Mortar Observed via In Situ (Timelapse) X-ray μCT imaging

This paper studies the evolution of internal damage in fresh cement mortar over the 25 hours of hardening. In situ timelapse X-ray computed micro-tomography (μXCT) imaging method was used to detect internal damage and capture its evolution in cement hydration. During μXCT scans, the hydration heat was measured, which provided insight for the internal damage evolution with a link to hydration heat development. The measured hydration heat was compared with an analytical prediction, which showed a relatively good agreement with the experimental data. Using 20 CT scans acquired throughout the observed cement hydration, it was possible to obtain a quantified characterisation of the porous space. Additionally, the use of timelapse μXCT imaging over 25 hours allowed to study the crack growth inside of the meso-structure including its volume and surface. Observed results provide valuable insights to cement mortar shrinkage.