ABSTRACT
Experimental and analytical studies into the behaviour of steel fibre reinforced concrete under direct shear were undertaken. The investigation looked at the performance of individual hooked-ended and straight fibres crossing a cracking plane, oriented at various angles, and tested in shear. The fibres were oriented at angles of ±75°, ±60°, ±45°, ±30°, ±15°, and 0° with respect to a plane perpendicular to the loading direction with embedment length ratios (each side of the crack relative to the fibre length) of 0.5:0.5 and 0.25:0.75. The combined effects of axial force in the fibres and bending of the fibres were more pronounced for the acute angles which exhibited fibre fracture behaviour whereas fibres oriented at obtuse angles failed in a pull-out mode. A series of non-destructive tests utilising radiographic techniques were also carried out on hooked-ended and straight fibres oriented at various angles to the cracking plane with an embedment length ratio of 0.25:0.75. The non-destructive tests show the internal fibre behaviour at the various stages of loading and are a valuable tool in understanding steel fibre-concrete behaviour.
