This paper addresses the flexural behaviour of medium-strength and high-performance concrete reinforced with recently developed macro fibres made of basalt fibre reinforced polymer (BFRP) with the intended use in marine applications. Four different fibre volume fractions and two different aspect ratios were investigated. Mechanical properties of fibre concrete were studied through an experimental programme consisting of 18 beam specimens and 45 cylindrical samples. Electrical resistivity testing was conducted to evaluate the performance of the concrete against chloride ingress. Three-point bending test was performed on beam specimens to assess the load-crack mouth opening displacement and load-mid span deflection curves, and to study their flexural behaviour, toughness, and ductility.
Since the operation of marine structures (concrete barges) starts minimum two months after the construction of concrete part, the hardened properties were also evaluated after sixty days. The results from the experimental tests indicated that the enhancement of concrete mechanical properties, including the toughness and ductility, were directly associated with the fibre content and concrete compressive strength. The post-cracking capacity of fibre concrete was found to be a function of the fibre volume fraction and the concrete compressive strength. Furthermore, the experiment showed that for the similar fibre content, fibres with an aspect ratio of 65 had a greater equivalent flexural strength, and the fibres with the aspect ratio of 83 had a higher post-cracking peak values.