Effects on Mechanical Properties of Industrialised Steel Fibres Addition to Normal Weight Concrete

Five groups of concrete grade C25 were produced with the addition of steel fibres (SFs) at different volumetric percentages: 0% (as control specimen), 0.5%, 0.75%, 1.00% and 1.25% by absolute concrete weight. SFs with aspect ratio, l/d=80 with 0.75 mm diameter and hooked at both ends were used in this study. The effects of adding SFs in concrete on its mechanical properties were measured for the cube compressive strength (f(cu)), splittting tensile strength (f(ct)), flexural tensile strength (f(t)) and also the Modulus of Elasticity in compression. For each group, nine cubes of 100 X 100 mm, four cylinders of 150 mm diameter X 300 mm long and four prisms of 100 X 100 X 500 mm were prepared and tested at 7,14 and 28 days. The mechanical properties of grade C25 concrete with and without SFs were determined in a comparative way by developing relationships between f(cu), f(t), f(ct) and percentage of steel fibres. These relationships were experimentally determined to reveal the quantitative effects of additional SFs to concrete for these measured properties. (C) 2011 Published by Elsevier Ltd.