Mechanical properties of GGBSFA Geopolymer concrete with varying Silica Modulus at different curing conditions

Abstract

Geopolymer concrete is made of waste materials such as Fly ash and ground granulated blast furnace slag (GGBS). The use of this concrete helps to reduce the stock of wastes and also reduces emission of carbon by reducing Portland cement demand. The major constituent of Geopolymer concrete is aluminium and silicon rich materials. These materials are either natural materials that are thermally activated (e.g. kaolinite) or byproducts from industries (e.g. fly ash ). These materials are activated using alkaline activating solution which polymerizes the materials and forms into networks creating hard binder. Geopolymer concrete with Fly Ash as precursor gains less strength at low rates in ambient temperature. Fly Ash Geopolymer concrete should be heat cured to improve its strength. In the present investigation effect of Silica Modulus(SiO2/Na2O) and percentage Na2o on the mechanical properties of Geopolymer concrete cured with Plastic Membrane and in ambient temperature are presented. In this alkaline activator which is combination of NaoH(NH) and Na2Sio3(NS) is used to activate the binder.8 type of mixes with fixed binder content, varying GGBS, Fly Ash ratio and Silica Modulus of Alkali solution are used to study the strength properties of Hardened concrete. It was found that the strength decreased with increase in Silica Modulus and increased with increase in percentage Na2o.M40 grade concrete is attained for a combination of Silica Modulus of 1.4 and 5.399 percent of Na2o.