Development of sustainable concrete repair materials via microencapsulated agents

Abstract

Identification of non-structural damage in concrete infrastructure and actuation of preventive repair solutions is an established approach to avoid further structural damages and more expensive repair regimes. However the repair of concrete itself is not infallible with 55% of reported repairs in the EU failing within 5 years of service. Thus the already once repaired concrete structure is then subject to a constant cycle of repeated repair and a cumulative associated life cycle cost. The development of external repair material with self-healing capabilities, can affect a real step-change on the life-cycle costs and maintenance of existing and new infrastructure. Developed polymeric microcapsules containing liquid sodium silicate were used to impart autonomic self-healing to readily available commercial repair mortars for the first time. These materials cover a range of potential real time repair applications. Initially the compatibility between the developed self-healing agents and commercial products was established and the self-healing performance of the novel composite system was then evaluated. The results underlined the huge potential for the proposed composite systems as a stepping stone toward commercial uptake of self-healing microcapsule-based cementititious materials.