Anchorage behaviour and development length of headed bars in exterior beam–column joints

Six exterior beam–column joint specimens with and without transverse shear reinforcement were constructed and tested under cyclic loading to assess the anchorage strength of headed bars with short development length. The test results demonstrated that the beam–column specimen without transverse shear reinforcement can exhibit satisfactory seismic behaviour with headed bars up to a drift ratio of 3%; above this the role of transverse shear reinforcement is vital. The test results also indicated that hysteretic behaviour of exterior beam–column joints with headed bars was superior to joints constructed and tested with 90° bent bars with sufficient anchorage length.