From bones to mortars, a visit to the doctor for the study of self-healing

Often compared to the healing process of bones, self-healing of mortars is the process by which the precipitation of CaCO3 at a crack opening leads to its closure. This is an effective method of extending the service life of structures [1]. Currently, multiple methods exist to assess the effectiveness of self-healing, yet coupled experiments are scarce. In this work, we show how a visit to the doctor would also benefit the study of mortars. We couple the standard self-healing assessment techniques, microscopy and water permeability tests, with micro-Computer Tomography (μCT). CEM II/A-LL 32.5R mortar was casted in cylinders of 45 mm diameter, adapted for water permeability tests [3], and cracked at 7 days. Three samples (S) were placed in 1 hour wet/ 23 hour dry cycles for 112 days. Water permeability tests were performed at 0, 28 and 112 days, superficial crack closure was assessed at 0 and 112 days and samples were scanned using μCT at 0 and 28 days. The results highlight the importance of coupled tests to provide a more comprehensive evaluation of the process and internal dynamics of self-healing in mortars.