Study of Flexural Behavior of Hybrid Fibre Reinforced Geopolymer Concrete Beam

Concrete is the most common building material in the world and its use has been increasing during the last century as the need for construction projects has escalated. One of the potential materials to substitute for conventional concrete is geopolymer concrete (GPC). GPC is an inorganic alumino-silicate polymer synthesized from predominantly silicon, aluminum and by-product materials such as fly ash, Ground Granulated Blast Slag etc. The main objective of this study is to investigate the impact of steel fibres and hybrid polypropylene- steel fibres on the mechanical flexural behavior of GPC. Crimped steel fibre with varying percentages (0 %, 0.25 %, 0.5 %, 0.75 % & 1 %) is adopted in this study. And then polypropylene fibre is added to the optimum steel fibre mix with varying percentages (0 %, 10 %, 20 %, 30 % & 40 %). The addition of bres changes its brittle behavior to ductile with signicant improvement in tensile strength, tensile strain, toughness and energy absorption capacities. For curing, temperature was fixed at room temperature for 24 hours. The concrete specimens were tested for mechanical properties of concrete namely cube compressive strength, split tensile strength, flexural strength and other tests were conducted for cement, chemical admixture, coarse aggregate & fine aggregate. The results of the experimental program reveal that mechanical properties of GPC are improved with the addition of fibres and also improve the load carrying capacity of beams.