X-ray computed tomography of fibre reinforced self-compacting concrete as a tool of assessing its flexural behaviour

The aim of the presented research programme was to investigate the flexural behaviour of steel fibre reinforced self-compacting concrete beams. The tested beams were reinforced with two types of crimped steel fibres. Fibres were added in volumes of 0.5, 1.0 and 1.5 %. The experimental tests were conducted on specimens cut from 1.2 m long elements. Before destructive mechanical testing the specimens were subjected to medical X-ray computed tomography (XCT) procedures. Results of XCT allowed to determine the distribution of fibres. The flexural behaviour of the beams was tested according to the RILEM TC 162-TDF recommendation. A comparison of non-destructive results and mechanical behaviour of tested specimens proved a very strong dependence. XCT also made it possible to assess the uniformity of fibre distribution throughout the tested elements. The influence of the location of concrete casting on fibre distribution was determined. The influence of mixture flow on fibre orientation was also analysed.