Effect of Silica Fume and Wood Ash Additions on Flexural and Splitting Tensile Strength of Lightweight Foamed Concrete

Abstract

Reducing building material costs by identifying sustainable and green construction materials is desirable for economic reasons and environmental responsibility. This study examines ways to enhance strength of foamed concrete by adding wood ash (WA) and silica fume (SF). The effect of different percentage combinations is investigated, to understand the effect on the flexural and splitting tensile strengths. The supplementary binders replace a percentage by weight of the cement and are blended with foamed concrete. The WA–SF mixes at 5%–15%, 10%–10%, and 15%–5%, were compared to standard foamed concrete. The microstructures show evidence of novel densification and there was an improvement in the flexural and tensile strengths. The 5% WA–15% SF mix has the most significant effect on the foamed concrete compared to the control. The binder matrix also prolonged the setting time of the cement paste.