Experimental investigation on structural behavior of mono and hybrid fibre reinforced concrete elements

Abstract

In recent years, earthquakes have prompted the structural engineering community throughout the world to pursue considerable research on the behavior of structures under cyclic loading. The concept of using fibres to reinforce a brittle material is not innovative. As per American Concrete Institute (ACI) guidebook of concrete practice, the utilization of two or more types of fibres in a concrete mix is considered as a promising concept. An appropriate mixture of fibres produces a better composite concrete than individual fibres for special applications. In the present research, the experimental studies are carried out to investigate the structural behavior of fibre reinforced concrete elements of M30 grade using micro and macro steel fibres. The combined effect of micro and macro fibres in beams, beam-column joints and slab specimens are investigated both experimentally and analytically. The maximum volume fraction of steel fibres used are restricted to 1.5% by volume of concrete. The mechanical properties like compressive strength, split tensile strength, newlineflex ural strength and modulus of elasticity of the conventional concrete specimen, single fibrous concrete specimen and hybrid fibre reinforced concrete specimen with various combinations of micro and macro steel fibres with a volume fraction of 0.75%, 1% and 1.5% are found and compared. It is observed that an increase in compressive strength, split tensile strength, flexural strength and modulus of elasticity is observed for the specimens with the combination of micro and macro steel fibres with a total volume fraction of 1.5%. newline newline