207 Experimental analysis of monotonic and cyclic pull-out of steel fibres by means of acoustic emission and X-ray microfocus computed tomography

This research aims to investigate the monotonic and cyclic pull-out behavior of steel fibres by means of advanced non-destructive testing methods (NDT). Forty individually embedded steel fibres in a concrete matrix are tested in a pull-out setup with continuous acoustic emission monitoring and X-ray microfocus computed tomography is applied before, during and after testing. The developed setup allows to improve and to better control the experiments. The combination of NDT methods leads to a deeper insight compared to the traditional pull-out tests, by inspection of deviating results, detection of the pull-out stages, and localization of internal damage combined with visualization of the internal structure.