Ultrasonic evaluation of self-healing cementitious materials with superabsorbent polymers: Mortar vs. concrete

The inclusion of superabsorbent polymers (SAPs) has become increasingly attractive to promote the self-healing ability of cementitious materials, thereby reducing the costs related to manual repairs. To advocate the use of these additives within large-scale constructions, an assessment of the self-healing ability is needed to ensure the safety of infrastructures. A non-destructive evaluation method was found in the adoption of ultrasonic monitoring. Thanks to the sensitivity of ultrasound to the elastic properties, the technique allows to determine the self-healing effectiveness and to compare the healing capacity between different mixtures. However, most studies concerning ultrasonic assessments of the healing evolution were conducted on mortars, lacking large aggregates. Therefore, to upgrade to the most commonly used construction material, self-healing of concrete is monitored, and its performance is compared to mortar. Ultrasonic surface wave monitoring shows the potential to evaluate the crack closure in either mixture and the effect of different SAPs included.