Bond characteristics of steel fibre reinforced self-compacting concrete

Steel fibre reinforced self-compacting concrete (SFRSCC) is a relatively new composite material that combines the benefits of the self-compacting concrete (SCC) technology with the advantages derived from the fibre addition to a brittle cementitious matrix. Steel fibres improve many of the properties of SCC elements including tensile strength, ductility, toughness, energy absorption capacity, fracture toughness and cracking. Although the available research regarding the influence of steel fibres on the properties of SFRSCC is limited, this paper investigates the bond characteristics between steel fibre and SCC. Based on the available experimental results, the current analytical steel fibre pullout model is modified by considering the different SCC properties and different fibre types (smooth, hooked) and fibre inclination. To take into account the effect of fibre inclination in the pullout model, apparent shear strengths (tau((app))) and slip coefficient (beta) are incorporated to express the variation of pullout peak load and the augmentation of peak slip as the inclined angle increases. These variables are expressed as functions of the inclined angle (phi).