Drying shrinkage and permeability properties of fibre reinforced alkali-activated composites. (10th August 2020)

• Record Type: Journal Article
• Authors: Adesina, Adeyemi; Das, Sreekanta
• Is Part Of: Construction & building materials. Volume 251(2020)
• Publication Date: 2020-08-10
• Subjects: Alkali-activated composite -- Fibre-reinforced composite -- Drying shrinkage -- Permeability properties -- Microstructure; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.119076
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Fibre-reinforced alkali-activated composites were developed. The composites were made by activating BFS and/or FA with hydrated lime. Drying shrinkage and permeability properties of the composites were evaluated. Non-destructive tests were used to assess the quality of the composites. Composites made with 50% BFS and 50% FA was found to be the optimum. Abstract: This study presents the durability investigation in terms of drying shrinkage and permeability properties of three fibre-reinforced alkali-activated composites. These composites were made with lime activated blast furnace slag and/or fly ash as a binder and reinforced with polyvinyl alcohol (PVA) fibres. The permeability properties investigated are the sorption, sorptivity, and volume of permeable voids of the mixtures. Two non-destructive tests which are ultrasonic pulse velocity and the surface resistivity of the mixtures were also undertaken. Results from this study showed that the incorporation of fly ash into the mixture as the aluminosilicate precursor reduces the drying shrinkage of the mixtures significantly. However, there is a detrimental effect on the compressive strength and permeability properties of the mixture with the introduction of the fly ash due to its lower reactivity. Nevertheless, the permeability properties of the composite incorporating 50% slag and 50% fly ash as a binder were found to be optimum in terms of the overall performance. A microstructural investigation carried out on the mixtures further confirms the experimental results obtained.