Influence of adding steel – glass – polypropylene fibers on the strength and flexural behaviour of hybrid fiber reinforced concrete

This experimental research investigates the strength and load deflection characteristics of hybrid fiber reinforced concrete. Two or more types of fibers are combined to improve the overall properties of concrete. Grade of concrete chosen for study is M40 and the specimens were incorporated with 0.75% volume fraction of Steel, Glass and polypropylene fibers in equal proportions and in different combinations. This study primarily focused on compressive strength, split tensile strength and flexural tensile strength of composite with two types of fiber combinations. Results were compared with non-fibrous control concrete and strength effectiveness was observed to be more in Steel- Polypropylene fibers combination. Negative results were produced by Glass- polypropylene hybrid fiber composites. Based on the best strength results reinforced concrete beam specimen is made with Steel – polypropylene hybrid fiber combinations as a secondary reinforcement and it is tested under flexural loading conditions. Load deflection behaviour and crack studies were carried out on tested beam specimens. Finally experimental results were compared with Finite element software results and close agreement was observed between them.