Ductility index and durability in fiber-reinforced concrete

To investigate the flexural behavior of fiber-reinforced concrete beams, even in the presence of traditional steel rebar, an experimental campaign has been carried out performing three-point bending tests. Conventional raw materials have been used to cast the concretes, which contain different amounts of steel fibers combined, in some cases, with a fixed amount of rebar. In addition, the use of a patented high performance selfcompacting fiber-reinforced concrete mixture has been analyzed. In all these cases, the ductility index, measured on the experimental load-deflection curves and used to assess the brittle/ductile behavior of the beams, can also be correlated with some durability parameters. Specifically, better fresh properties of concrete and the increment of flexural ductility improve the resistance to water penetration. In other words, the higher the ductility index the longer the beam durability measured in accordance with major standards.