Shrinkage and settlement assessment of fresh concrete using Digital Image Correlation (DIC) and Acoustic Emission (AE)

Concrete undergoes displacements and volume changes due to ongoing processes such as settlement, hydration, shrinkage, and early-age cracking, which can strongly affect its durability and long-term performance. In the present paper, the displacement of concrete is measured by Digital Image Correlation (DIC), a contactless technique that can provide a global measurement of the whole surface allowing a real-time mapping of the horizontal (shrinkage) and vertical displacements (settlement). The motivation of this study is to obtain a real-time full-field 3D view of deformations and strains when novel admixtures for internal curing and self-healing, like SuperAbsorbent Polymers (SAPs), are added to the mixture. These admixtures strongly modify the microstructure influencing the displacement history. Two concrete cubes were monitored, one reference and one containing SAPs. Results were complemented by Acoustic Emission (AE), providing a full methodology of non-intrusive techniques for monitoring the crucial fresh state of concrete.