Seismic behaviour of RC external joints

The behaviour of reinforced concrete beam–column connections under cyclic loading has been extensively investigated to date. A common feature of the results published is that, in contrast with current design objectives, connections are characterised by extensive cracking and large deformation before the plastic hinge formation within the linear elements. The present work describes an attempt to minimise cracking and deformation of the joints through the use of steel plates for anchoring the beam's longitudinal reinforcement and alternative reinforcement arrangements in the joint. The results obtained from tests on full-size beam–column subassemblages indicate a considerable improvement in behaviour, in spite of the significant reduction in reinforcement congestion.