Toughness of Steel Fiber Reinforced Silica Fume Concrete Under Compression

Concrete steel fiber composite is increasingly used day by day as a structural material for various applications, especially in the area of earthquake resistance structures. The complete stress-strain curve of this material in compression is needed for its behavior and the toughness properties. In this experimental study, an attempt has been made to generate the complete stress-strain curve of steel fiber reinforced concrete with a compressive strength range of 52–75 MPa, for water-cementitious materials ratio of 0.40 and 0.3 with 10% silica fume replacement. Crimped fibers with fiber volume fractions of 0.5%, 1.0% and 1.5% with an aspect ratio of 80 are considered in this study. The effects of fiber addition on the shape of stress-strain curves and toughness ratio are presented and discussed. Test results indicate that inclusion of steel fibers to silica fume concrete improves the compressive strength moderately, and ductility and toughness considerably. Equations are proposed to quantify the effect of fibers on compressive strength, and toughness ratio of concrete in terms of fiber reinforcing index and elastic modulus. The proposed equations are giving good correlation with the experimental values.