Effect of alkali activator ratio on mechanical properties of GGBS based geopolymer concrete

Abstract

Geopolymer concrete also referred to as “green” and “environmentally friendly” concrete is carbon free binding material which can be ultimate replacement for traditional Ordinary Portland cement (OPC) concrete. OPC production is solely responsible for seven percentage (7%) of carbon dioxide (CO2) gas emission globally. Taken in account, the serious threats imposed by ordinary Portland cement in coming future with its increasing use in construction projects, ecofriendly geopolymer concrete which aren’t harassing to surroundings will be a boon in Civil engineering field. Here, in this paper we studied the behavior of Geopolymer Concrete using (GGBS) under the effect of varying concentration of Alkali Activators. The alkali activators Sodium Hydroxide (NaOH) and Sodium Silicate (Na2SiO3) with Alkali Activator ratio (AAR) of 1:1.5, 1:2 & 1:2.5 were used. Also, the molarity of NaOH was altered for 8Molar, 10Molar and 12Molar. The specimens were casted for Compressive, Split Tensile and Flexural test and were tested after 7 days and 28 days of ambient curing. It was observed that Compressive, Split Tensile and Flexural strength of the GPC specimen increased with increasing molarity of Sodium Hydroxide (NaOH) and with increase in Alkali Activator Ratio.