Strength and deflection characteristics of concrete reinforced with steel swarf

This paper reports the strength characteristics of concrete reinforced with steel swarf at varying percentages. A total of forty-five concrete specimens were investigated; with a mix proportion of 1:2:4 and water-cement ratio of 0.55, fifteen numbers each of 150mm concrete cubes, 150x300mm concrete cylinders and 150x150x750mm beams, were cast and tested for density, compressive, tensile and flexural strengths. The results showed that workability of Swarf Reinforced Concrete (SRC) is not significantly affected at 0.5% steel swarf content but decreased as the percentage of steel swarf increased. The density of SRC increased as the percentage of fibres increased, due to the material property of the steel swarf. The compressive strength of swarf concrete as compared to normal concrete was found to increase by 1.7%, 4.8% and 5.6% for 1%, 1.5% and 2% swarf content respectively. The obtained increase in the tensile strength was 5.2%, 3.9%, 13% and 26% for 0.5%, 1%, 1.5% and 2% swarf content respectively. Using regression analysis, Index models for compressive strength and tensile strength with respect to the swarf content was developed at high coefficient of correlations (R² values) of 0.9398 and 0.9601 respectively. The maximum failure load recorded for swarf concrete was 2.5 times higher than that of plain concrete. The significant increase in the failure loads for the 1.5% and 2% steel swarf content is an indication that there was good bond between the concrete and the steel swarf. The maximum deflection of 0.57mm was recorded for swarf concrete beams. This is an increase of 103% compared to plain concrete beams. The SRC is able to sustain further deformation under increased load; this is as a result of increased load carrying capacity and ductility of the beam section, which is due to the strength and ductility properties of the embedded steel swarf. (paper)