The improvement of fly ash based geopolymer concrete by inclusion of hooked steel fibers

Geopolymer concrete is an innovative construction material that utilized fly ash as one of waste material in coal combustion industry as a replacement for ordinary Portland cement in concrete. However, the plain geopolymer concrete suffers from numerous drawbacks such as brittleness and low durability. This research purpose to increase the brittleness of geopolymer concrete by inclusion hooked steel fiber cured under room temperature, the sample preparation by mixing of fly ash class F, alkaline activator, difference percentage of hooked steel fiber, and lastly by adding fine aggregate (river sand) and coarse aggregate (granite). The result showed the density of steel fiber reinforced geopolymer concrete produced is almost similar to the conventional of steel fiber reinforced OPC concrete. Meanwhile, inclusion of hooked steel fibers significantly enhance the both compressive and flexural strength of geopolymer concrete. The improvement also increase with the addition of hooked steel fibers by volume fraction.