No abstract

CARDIFRC is the trade name of two main groups of ultra-high performance fibre-reinforced concrete mixes-Mixes I and II-differing primarily in the maximum size of quartz sand used (0.6 mm in Mix I, and 2 mm in Mix II). In this paper, the conversion of CARDIFRC Mix II to a self-compacting and industrially competitive ultra-high performance fibre-reinforced concrete (UHPFRC) is described. A full mechanical and fracture characterisation (i.e. size-independent fracture energy and the corresponding bi-linear stress-crack opening relationship) of this UHPFRC is provided.

The aim of this paper is to describe the performance of reinforced concrete (RC) beams retrofitted with a self-compacting ultra-high-performance fibre-reinforced concrete (UHPFRC) under three-point bend cyclic loading. It is found that retrofitting the RC beams with a thin UHPFRC strip on the tension face increases their endurance limit under a non-zero mean stress cyclic loading from approximately 40% to approximately 60% of their static three-point flexural strength. Moreover, the retrofitted beams behave as a composite structure, with no delamination of the retrofit strip being observed in any of the fatigue tests.