Utilising microCT scanning technology as a method for testing and analysing plastic shrinkage cracks in concrete

Plastic shrinkage cracking is tested by placing fresh concrete in a restrained mould and exposing it to high evaporation conditions. Plastic shrinkage cracking was studied using microCT scanning technology, which allowed the cracking and volume change to be studied below the surface of the concrete. The effect of the level of restraint on plastic shrinkage cracking was also analysed. The study showed that the shrinkage occurring in the concrete is isotropic, even with the formation of a crack. The settlement voids under reinforcing bars form almost immediately after casting the concrete and is mostly a problem in conditions with high evaporation.