ABSTRACT
ABSTRACT This paper reports the first results of an experimental programme investigating the fatigue behaviour of steel fibre reinforced concrete (SFRC). As a first step in this research, uniaxial monotonic and cyclic pull-out tests of partially and individually embedded steel fibres in a concrete matrix are performed. Furthermore, an experimental setup is developed to perform these pull-out tests in combination with the advanced non-destructive measurement techniques of Acoustic Emission (AE) sensing and X-ray microfocus Computed Tomography (micro-CT scans). The varying parameters are the type of hooked-end fibre (3D or 5D), the embedded length, the fibre orientation, and the loading pattern. The developed setup allows to improve and to better control the experiments. As a result, concrete cracking and pull-out behaviour are determined more accurately. The AE activity is higher for 5D hooked-end fibres compared to 3D hooked-end fibres. Furthermore, the localisation of damage during pull-out tests represents the different stages of fibre pull-out. Lastly, outliers with respect to the bond-slip behaviour of the pull-out tests are visually confirmed with the micro-CT scans. In conclusion, the combination of the AE technique and the micro-CT scans leads to a deeper insight and understanding of the fatigue behaviour of steel fibres embedded in concrete.
