Utilization of silica fume for the production of self compacting GGBS based geopolymer concrete

Geopolymer concrete (GPC) is the most predominant alternate for cement concrete in construction industry which can highly reduce the CO₂ emission by the cement production. Self-Compacting Concrete (SCC) is also the growing technology that can help to pour the concrete in congested reinforcement sections. The effort is initiated to utilize the GGBS and Silica Fume (SF) as binders to create the Self Consolidating GPC (SCGC). GGBS based geopolymer concrete lacks in rapid setting and sticky nature with the formulation of calcium silicate hydrate gel. Silica fume has most finer particles and it is used to replace the GGBS at 0 to 100 percent at 10 percent increment levels. The impact of various replacement levels of SF with GGBS on the rheology and mechanical behaviour are assessed. The findings indicate that increasing the replacement percentage of silica fume enhances flow properties due to the presence of finer particles that contribute to fluidity. However, higher silica fume percentages lead to a reduction in hardened properties. Notably, the mixture comprising 70 percent GGBS and 30 percent silica fume achieved a compressive strength of 39.8 MPa, which closely approaches the compressive strength of the all GGBS mixture. This blend, considered optimal, exhibited improved flow properties alongside its notable compressive strength performance. Hence the mix with 70 percent of GGBS and 30 percent of silica fume can choose as optimum mix for the production of self compacting geopolymer concrete with nominal strength.