Engineering properties of Class-F fly ash-based geopolymer concrete

Concrete is the most utilized building material in the world. Ordinary Portland Cement (OPC) is a core ingredient in the manufacturing process of concrete. For every tonne of OPC produced, approximately one tonne of carbon dioxide is released into the atmosphere. Increasing environmental awareness means alternative binders are being considered in the ever growing demand for building construction. The development of geopolymer concrete aims to reduce the need for OPC concrete by using constituents that would otherwise be considered as industrial waste to form a binder. This study presents an experimental program aimed to develop an optimum mix design using fly ash. The engineering properties of this mix was tested, analyzed and compared with prediction models developed for OPC-based concrete. The comparison suggests that existing OPC models provide reasonably accurate predictions of the elastic moduli and stress-strain relationships, whereas they slightly underestimate flexural and splitting tensile strengths.