The Effect of HCWA-PFA Hybrid Geopolymer Modification on the Properties of Soil

Abstract

Abstract. This study investigated the performance of the properties of foamed concrete when replacing volumes of cement of 10%, 15% and 20% by weight. A control unit of foamed concrete mixture made with Ordinary Portland Cement (OPC) as well as samples containing 10%, 15% and 20% silica fume were prepared. Three mechanical property parameters of foamed concrete containing different percentages of silica fume were studied: compressive strength, flexural strength and splitting tensile strength. Silica fume is commonly used to increase the mechanical properties of concrete materials as well as for economic concerns. The foamed concrete in this study was cured at a relative humidity of 70% and a temperature of ±28°C. Improvements in the mechanical properties of foamed concrete were due to a significant densification in the microstructure of the cement paste matrix in the presence of silica fume hybrid supplementary binder as observed from micrographs obtained in the study. The overall results showed that silica fume has great potential to be utilized in foamed concrete as there was a noticeable enhancement in thermal and mechanical properties with the addition of silica fume.