Self-healing assessment of cementitious mortars through ultrasonic monitoring

Abstract

Self-healing cementitious composites have gained increased attention over the past decades, encouraged by the excessive costs related to manual concrete repair. Thorough investigations on these materials have shown their potential to be applied for real life construction elements. However, the existing methods used to assess the self-healing effectiveness possess several limitations, making an in-situ evaluation of the regained properties practically impossible. This study therefore investigates a non-destructive testing methodology based on ultrasonic wave propagation that can eventually be practically implemented. The sensitivity of ultrasound to the elastic properties of the material under study allows to assess the self-healing effectiveness and discriminate between actual healing, in the sense of mechanical properties restoration, and simple filling of the crack. Moreover, the method is validated and complemented by numerical wave simulations that allow to connect the macroscopically measured wave velocity to the stiffness of the healing products deposited within the crack.