Abstract:
The application of headed reinforcement as a replacement for conventional reinforcement was investigated in two projects relating to the seismic design of bridges. In the first project, a test unit composed of a column, cap beam, footing and knee joint was designed entirely with headed reinforcement, and in the second project a test unit representative of a multi-column bridge bent was investigated, having a cap beam design utilizing both headed reinforcement and a mechanical coupler system. In both investigations the use of recently-developed products facilitated simplified detailing, particularly in the cap beam/column joint region, resulting in reduced reinforcement congestion in the joint zone and improved constructability. The design and performance of the test units under simulated seismic loading are presented.