Characterisation of cement pastes with innovative self-healing system based in epoxy-amine adhesive. (July 2015)

• Record Type: Journal Article
• Authors: Perez, G.; Gaitero, J.J.; Erkizia, E.; Jimenez, I.; Guerrero, A.
• Is Part Of: Cement & concrete composites. Volume 60(2015)
• Page Start: 55
• Page End: 64
• Publication Date: 2015-07
• Subjects: Microcapsule -- Nanosilica -- Self-healing -- Cementitious material -- Characterisation -- Microstructure; Composite-reinforced concrete -- Periodicals; Concrete -- Periodicals; Composite materials -- Periodicals; Composites de ciment -- Périodiques; Béton -- Périodiques; Composites -- Périodiques; Béton léger -- Périodiques; Cement composites; Composite materials; Composite-reinforced concrete; Concrete; Lightweight concrete; Periodicals; Electronic journals; 620.135
• DOI: 10.1016/j.cemconcomp.2015.03.010
• Languages: English
• ISSNs: 0958-9465

Abstract

Abstract: Two innovative additions are considered for the development of self-healing concrete: epoxy-containing silica microcapsules and amine-functionalized nanosilica. The effect of two concentrations of the additions on the microstructure of a cement paste with silica fume is studied. The results indicate a proper dispersion of the additions within the matrix, a pozzolanic reaction induced by nanosilica and the stability of the microcapsules that reliably isolate the epoxy from the paste. As the concentration of additions increases, a preferential orientation of the portlandite phase is observed, together with a decrease of the compressive strength due to the presence of a minor content of macropores and to the low strength of the capsules. The self-healing efficiency is confirmed in concrete specimens for 150 μm wide cracks and a particular concentration of the additions. These results will be essential for the subsequent development of a reliable self-healing concrete based in the epoxy-amine adhesive.