Mechanical properties of fly ash based geopolymer concrete with full and partial cement replacement

Abstract Concrete is the most widely used building material in the construction of infrastructures such as buildings, bridges, highways, dams, and many other facilities. The increasing of worldwide production of ordinary Portland cement (OPC) to meet infrastructure developments indicates that concrete will continue to be a chosen as the most common material of construction in the future. The production of cement consumes a lot of energy and increase CO 2 emission to the atmosphere. Another alternative to make environment-friendly concrete is the development of geopolymer which is an inorganic alumina-silicate polymer, synthesized from materials of geological origin or by-product materials such as fly ash which is rich in silicon and aluminum. In this paper 18 concrete mixtures were produced to evaluate the effect of key parameters on the mechanical properties of concrete and its behavior. The study key parameters are; binder material content, cement replacement ratios, and the activator solution ratio as a fly ash based geopolymer. The test results showed that replacement of fly ash as-based geopolymer improved the mechanical properties of concrete. Compressive strength, splitting tensile strength, flexural strength and bond strength are on higher side for 50% replacement as compared to those produced from 0%, 25%, 75% and 100% cement replacement ratio.