Abstract
This study was undertaken in order to investigate the structural behaviour of novel Engineering Cementitious Composites (ECC) columns subjected to eccentric loading. These columns were experimentally formulated using a hybridization of steel and polypropylene fibres. Two ratios were adopted for the steel fibres of 0.5% and 1%, whilst the polypropylene fibre was kept to be constant at a ratio of 0.5% for all of the ECC columns. The eccentric loads were applied at two eccentricities: small (h/6) and large (5h/12). A comparison was also made with the behaviour of self-compacting concrete and traditional ECC columns containing either steel or polypropylene fibres. The vertical and lateral deformations as well as the maximum load at failure were noted. The results obtained showed that the hybrid ECC columns exhibited higher load carrying capacities when compared with those of both self-compacting concrete and traditional ECC columns. The percentage increase was 30%. The hybrid ECC column samples containing 1% steel fibre did not show a signification difference in the load-deformation behaviour when it compared with that containing 0.5% steel fibre. The values of eccentricity governed the global behaviour of the tested columns. The predicated load carrying capacity of the ECC columns needs a magnification factor in case of concentric test, and to take into account the existence of fibres ratio when calculating the area of steel reinforcement for eccentric loading.