Enhanced impact energy absorption in self-healing strain-hardening cementitious materials with superabsorbent polymers

Concrete is the most-used man-made construction material worldwide. One of its major flaws remains the susceptibility to cracking upon impact loading. In this study, plates containing different amounts of superabsorbent polymers were impacted at four different ages (1 week, 1 month, 4 months and 6 months) and stored at different healing conditions (wet/dry cycles and 95 5% RH). After 28 days of healing the plates were impacted and healed again. When the deformations during impact and the rebound after the impact were analysed, the specimens containing SAPs showed a more ductile behaviour during impact loading compared to reference samples. A good healing was confirmed by natural frequency analysis. Even during a second impact loading of healed samples a significant regain in natural frequency was obtained. The evolution of the natural frequencies also showed a superior healing caused by wet/dry cycles compared to healing at 95 5% RH. Only in specimens with SAPs, the healing condition of 95 5% RH resulted in a regain in natural frequencies due to the moisture uptake by the SAPs and subsequent healing. (C) 2018 Elsevier Ltd. All rights reserved