Code provisions and practical design examples of hooked bar anchorage

In structural concrete, hooked bars are used to shorten anchorage length when the requirements for straight bar anchorage cannot be provided within the available dimensions of elements. The objective of this study was to provide an overview of hooked bar anchorage. Design examples and structural details are based on Building code requirements for structural concrete (ACI 318-08) and commentary. Examples of standard hooks in exterior beam-column joint and hooked bar anchorage details for reinforced concrete beam-SRC column joints are discussed. The general behavior of anchorage of hooked reinforcing bars is summarized from a review of previous studies. Then, design requirements for the development length of standard hook are discussed and used in an example. An example of the use of hooked bars in reinforced concrete beam-SRC column joint is provided. Four options for short development length are presented and compared: Adding more reinforcement, welding bars, confinement by steel column flanges, and anchorage by plate welded between flanges.