Fiber-matrix bond strength by pull-out tests on slag-based geopolymer with embedded glass and carbon fibers

Abstract

The reinforcement efficiency on a composite depends on the effective transfer of the stress between matrix and fiber. This work presents an experimental and comparative study of fiber-matrix bond strength for fiber-matrix interface between glass fibers and carbon fibers added to the slag-based geopolymer matrix. This analysis was performed by pull-out test. A total of 18 tests have been conducted, three for each type of fiber at each embedded length of 10 mm, 20 mm and 30 mm. The critical embedded length and the maximum interfacial shear (bond) strength were analyzed, and SEM observations were carried out for the cross-section of each fiber to measure diameter and observe the interface. It was found that the greatest efficiency was obtained by reinforcing with the glass fibers, incorporated at 20 mm in the slag-based matrix.

Keywords:

• Blast furnace slag
• cement Portland
• sodium silicate activating solution
• pull-out test
• glass fiber
• carbon fiber

Acknowledgments

The authors acknowledge the Brazilian institutions CAPES (Coordenação de Aperfeiçoamento de pessoal de nível superior – Coordination of Improvement of senior staff), CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico – National Council for Scientific and Technological Development) and Institut de Recherche en Génie Civil et Mécanique – Research Institute on Civil and Mechanical Engineering for their support in conducting experiments.

Disclosure statement

No potential conflict of interest was reported by the author(s).