Investigation of Self-Healing Phenomenon in High Performance Fiber Reinforced Microconcrete with Steel and Sisal Fibers
T.N. da C. Moreira, S.R. Ferreira, R.D.T. Filho
Abstract. High performance fiber reinforced concretes present advantages when compared with conventional concretes, such as greater tenacity, durability and crack control. Nevertheless, it can have great environmental appeal if part of the cement is replaced with blast furnace slag. Combining the lower environmental impact achieved by the adequate selection of the matrix with the self-healing potential of this type of composite, a greater economic and environmental value can be added to the family of advanced materials. The purpose of this research is to evaluate the self-healing phenomenon of high performance microconcrete reinforcement (0,64% in vol.) with steel and sisal fibers (lf =13 mm). The addition of vegetable fiber aimed to guarantee a better distribution of moisture in the matrix and to potentiate the phenomenon, but also to act as secondary reinforcement. The samples were cured for 28 days and then, under tensile loads, a single crack (200 µm) was induced. The micro-cracked specimens were subjected to wet and dry cycles for 3 months to allow the healing. After this period, the samples were re-tested under tensile loads until collapse. The evaluation of the healing potential was performed through two mechanical indexes: index of mechanical recovery (ITR1 and ITR2), which was the relation between the maximum stresses before and after conditioning. Microscopic analyzes were performed to evaluated the crack closure, as well as thermal analysis of the filler filling material to identify the hydration products present in the crack. The results indicate that partial/total recovery of mechanical behavior occurred and sisal fiber acted as nucleating agent.
Keywords
Self-Healing, Sisal, Steel, Crack Control, High Performance
Published online , 8 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: T.N. da C. Moreira, S.R. Ferreira, R.D.T. Filho, ‘Investigation of Self-Healing Phenomenon in High Performance Fiber Reinforced Microconcrete with Steel and Sisal Fibers’, Materials Research Proceedings, Vol. 7, pp 552-559, 2018
DOI: https://dx.doi.org/10.21741/9781945291838-53
The article was published as article 53 of the book Non-Conventional Materials and Technologies
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