Effect of Steel Fibers on Bond Strength of Hooked Bars in High-Strength Concrete

The effect of steel fibers in improving the bond performance of hooked-bar anchorages installed in high-strength concrete (HSC) beam-column connections was evaluated by testing twelve beam-column type specimens. The specimen simulated the rigid connection of a vertical cantilever beam to a base column. The tensile beam reinforcement consisted of two bars anchored in the column outside the column reinforcement cage using hooked-bar anchorages. The variables used in the study were the beam bar size (16, 25, or 32 mm) and the volume fraction of steel fibers added and dispersed in the concrete mix (0, 0.5, 1.0, or 1.5%). Analysis of the test results revealed that steel fibers were effective in increasing the anchorage capacity and the ductility of the load-deflection history of specimens with steel fibers as compared with companion specimens identical in geometry and bar size but without steel fibers.