Influence of GGBFS-based blended precursor on fresh properties of self-compacting geopolymer concrete under ambient temperature

Abstract

Geopolymer concrete having self-compacting nature is known as self-compacting geopolymer concrete (SCGC) which does not need mechanical compaction to improve the concrete density. The geo-polymerization process primarily depends on aluminosilicate materials and alkaline activator solution (AAS). The type of precursor material greatly affects the hardened concrete properties i.e. both the short-term and long-term concrete characteristics. The present study aims to achieve an optimal blended precursor-based SCGC possing acceptable fresh property characteristics where ground granulated blast furnace slag (GGBFS), the precursor in the control GGBFS-based SCGC is partially replaced by silica fume (SF), and rice husk ash (RHA) with various proportions. Mix proportions with the replacement of GGBFS by SF (10%, 20%, 30%, 40%) and RHA (5%, 10%, 15%, 20%) are prepared along with one control GGBFS-based SCGC. The fresh property of the nine SCGC mixes are interpreted through the filling ability (slump flow, T50cm slump, V-funnel); passing ability (L-box, J-ring), and resistance to segregation (V-funnel at T5minutes) test. All the ambient temperature-cured SCGCs are made with the following mix parameters: 12 M sodium hydroxide molarity, AAS ratio of 2.5, superplasticizer dose of 7%, and extra water of 24%.