Laboratory tests of the pull-out behaviour of spiral shaped steel fibres from concrete matrix

The pull-out tests were carried out using the Baldwin testing machine. Fig. 2 shows the schematic diagram of the test setup. The concrete block was mounted on top of a steel plate which was secured onto the Baldwin machine. Saw-toothed clamps were used to clamp the fibre while restrict slippage between fibre and clamping device. The clamp was connected to a 5 kN load cell. The fibre pull-out length was recorded by Linear Variable Differential Transformer (LVDT).