Effect of delay time and duration of steam curing on compressive strength and microstructure of geopolymer concrete

Abstract

Ordinary Portland cement (OPC) is conventionally used as a primary binder to produce concrete. The amount of carbon dioxide released during the manufacture of OPC is a matter of great environmental concern in view of global warming. Thus, alternative concrete technologies have become an area of increasing interest in research community. On the other hand, fly ash (FA), abundantly available by-product of coal fired thermal power plants poses great environmentalproblems in terms of its safe disposal. Therefore, use of FA as a replacement of cement in concrete production is one alternative, which is being widely used in the construction field. Geopolymer is a type of amorphous aluminosilicate cementitious material. This paper reports the results of an experimental study on the effect of delay time and duration of steam curing on thecompressive strength and microstructure development of FA based geopolymer concrete specimens prepared by thermal activation of FA with sodium hydroxide and sodium silicate solution.