Autogenous Healing in 10-Years Aged Cementitious Composites Using Microfibers and Superabsorbent Polymers

Abstract

Cement-based materials are the most widely used construction materials in the world for infrastructure works. Unfortunately, they come with a high environmental burden due to carbon dioxide emissions and the need for regular maintenance and repairs. Without these, the service life can decrease. By using a self-healing approach, the service life can be extended, as well as the durability and sustainability of the building material. As the ability to self-heal depends on the age of the material, so will the potential influence of added materials to promote this healing. However, the effects of reduced healing beyond one year are not ubiquitous in the literature. In this study, specimens were studied after a decade of maturation under different storage conditions to conclude on the self-healing capabilities of the old samples. Cracks can still be partially healed after ten years, mainly due to the formation of calcium carbonate crystals, related to the observed regain in mechanical properties measured by repeated four-point bending tests. The initial addition of superabsorbent polymers to the mixture results in greater healing compared to the reference samples, making it a sustainable option for the future of cement-based composites.