Contribution to study of the self-healing effect activated by crystalline catalysts in concrete structures when subjected to continuous exposure to water

Author(s): E.M. Takagi, M.G. Lima, P.R.L. Helene
Paper category: Conference
Book title: Concrete Repair, Rehabilitation and Retrofitting III (ICCRRR)
Editor(s): M.G. Alexander, H.-D. Beushausen, F. Dehn, P. Moyo
Print ISBN: 978-0-415-89952-9
Publisher: Taylor & Francis Group
Pages: 508- 509
Total Pages: 2
Language: English

Abstract: 
This paper aims to contribute to the study of the self-healing effects on high performance concretes activated by crystalline catalysts when subjected to continuous water exposure, as part of a postgraduate research program developed at the Instituto Tecnológico de Aeronáutica (ITA) in Brazil. For this purpose, a specific crystalline catalyst was selected to investigate the potential to act as a self-healing agent in concrete. Specimens of high performance concrete were prepared having a constant water/cement ratio of 0.50, with and without addition of these crystalline catalysts. A uniaxial compression load was applied to generate microcracks in cylindrical concrete specimens pre-loaded up to 90% of the ultimate compressive load determined at 28 days for 2 minutes. Later, the extent of damage was determined as a percentage of loss in mechanical properties by determining compressive strength recovery and percentage of increase in permeation properties and water absorption rate by monitoring for 28 and 56 days after preloading, during a period necessary for self-healing of these microcracks. The results of the recovery of strength and permeability will be attributed to the self-healing of these pre-existing microcracks, due to hydration of anhydrous particles of cement and especially by the activating effect of the crystalline catalyst, on the surfaces of these microcracks. This is determined as a percentage of gain of mechanical properties and the percentage of decrease in the permeability properties. The knowledge developed in this study makes it possible for the self-healing technology to be specified in the high performance concretes mix design in various applications in air transportation and airport infrastructure buildings, especially in hydraulic structures and underground constructions.

Online publication: 2014
Publication Type: abstract_only
Public price (Euros): 0.00