Effectiveness of low-cost fiber-reinforced cement composites in hollow columns under cyclic loading

This study is to investigate the effectiveness of low-cost fiber-reinforced cement composites (FRCCs) on improving the seismic performance of hollow bridge columns. FRCCs with an economical type of hooked steel fibers were used. Five 1/4-scale rectangular hollow columns were tested under quasi-static lateral cyclic loading. The main test variables included steel fiber volumetric ratio (0%, 1%, or 2%), the presence of coarse aggregates, and column length-to-depth ratio (2 or 3). In all specimens, no transverse reinforcement was provided to identify the sole contribution of concrete or FRCCs on the confinement as well as the shear strength. The specimens having FRCCs exhibited stable inelastic load-displacement responses up to 3% or 4% drift, even though they suffered severe shear cracks. In contrast, one specimen with normal concrete only showed very limited ductility. The specimen with the higher fiber ratio generally achieved the larger displacement ductility and the greater energy dissipation, and also better sustained intensive cracking damage.