Mechanical properties of fiber reinforced geo-polymer concrete made with three mineral admixtures and steel fibre at different ambient curing periods

Concrete consists of important elements such as binding cement, inactive fillers, fine aggregate, coarse aggregate and water. Among all materials, cement is the main compound that causes carbon dioxide emissions into the environment. This study completely replaces cement with industrial waste by-products in various proportions to produce geopolymer concrete (GPC). First, GPC remained a combination of fine aggregate, coarse aggregate, and low calcium (i.e., Class F) fly ash with an alkaline solution. Current work is focused on replacing low-calcium fly ash with ground granulated blast furnace slag (GGBFS) in various proportions along with a constant 10% condensed silica fume (CSF) in all blends. Various levels of steel fibres such as 0, 0.5, 0.75 and 1.00 are added to improve the tensile properties of GPC. Samples (i.e. cubes, cylinders, prisms) were cast in various mix combinations, cured under ambient conditions and tested after 7, 28, 45 and 60 days. The mechanical properties of geopolymer concrete were improved when low-calcium fly ash was replaced with constant rate ground granulated blast furnace slag(GGBFS) and condensed silica fume (CSF) and varying amounts of steel fibres.