Experimental Investigation of Effect of Hybrid Steel and False Banana Fibers on Concrete Properties

Abstract

Most of civil engineering construction that has been constructed in the world mainly uses concrete as construction material. But due to its weakness in tension resistance, concrete cannot be used alone. To overcome such problems, fibers have to be considered as an additive. The use of two or more types of fibers in a suitable combination may potentially improve the overall properties of concrete and also results in the performance concrete. The combination of fibers, often called hybridization, is investigated in this paper for a C25 grade of concrete. The main aim of the present experimental investigation was to combine different fibers namely steel fiber and false banana fiber to produce hybrid fiber reinforced concrete and to study the effect of each individual fibers on mechanical properties of concrete. Control and five fiber reinforced concrete composites were casted using different fiber proportions containing 1% of total volume of concrete. And the mix contains 1%, 0.75%-0.25%, 0.5%-0.5% and 0.25%-0.75% and 1% steel and false banana fibers respectively. Workability of fresh concrete using slump and compaction factor test and compressive test, flexural test and split tensile strength were performed and results were extensively analyzed to associate with the above fiber combinations. From the research, it was observed that the addition of fibers either in hybrid or mono fiber reduces workability of wet concrete .The compressive strength shows increment by 18.48 % and 12.49% for 1% SF and 0.75%SF-0.25%FBF respectively and it was below control for the rest mixes. The greater improvement was observed for tensile and flexural strength than compressive strength. The split tensile strength was increased as the percentage of steel fiber increased in the mix by 0.65%, 3.24%, 8.51% and 14.57% for 0.25%SF-0.75%FBF, 0.5%SF-0.5%FBF, 0.75%SF 0.25%FBF and 1%SF addition respectively. The maximum flexural strength was found at 0.75%SF-0.25% FBF combination. Additional load carrying capacity after peak load is more observed for fiber reinforced concrete than control. The crack bridging mechanism was more observed when the two fibers are used together than individual fiber. From the research, it was concluded that the greatest improvement in mechanical behavior of hybrid steel and false banana fibers was observed for 0.75%SF-0.25%FBF fiber content.