Formulation and performance evaluation of alkali-activated self-compacting concrete

Abstract

Extensive quantities of fly ash and ground granulated blast furnace slag are produced by power-generation plants and steel manufacturing industries. These superfluous by-products, instead of being left as waste, are used for producing alkali-activated self-compacting concrete, generally known as self-compacting geopolymer concrete. Geopolymer technology has shown its potential in completely eradicating Portland cement for producing concrete. The current study present the executability of developing free flow geopolymer concrete with diverse consequences of substitution of fly ash by ground granulated blast furnace slag (0%, 50% and 100%) and alkaline activator to cementitious binder ratio (0.1, 0.3, and 0.5) on fresh properties, strength development and durability properties. Various tests such as volume stability, sorptivity, water permeability, rapid chloride penetration, sulphate attack and acid attack were evaluated. The results concluded that partial to complete replacement of fly ash by ground granulated blast furnace slag not only eliminated the requirement for elevated curing treatment, but also improved the compressive strength and volume stability, whereas the alkaline activator to cementitious binder ratio effectively influenced the durability and strength development of self-compacting geopolymer concrete to a greater degree. Also, there was no remarkable enhancement in various properties with the use of high-range water-reducing chemical admixtures on the mix. A dominant parameter in deciding the potential adaptation of self-compacting geopolymer concrete in the construction sector is its durability parameters. The durability characteristics were evaluated in detail by activating the source products with a combined mixture of 10 M sodium hydroxide solution and sodium silicate with an alkaline activator ratio of 4.