Title: Use of Headed Reinforcement in Beam-Column Joints Subjected to Earthquake Loads

Author(s): John W. Wallace, Scott W. McConnell, Piush Gupta, and Paul A. Cote

Publication: Structural Journal

Volume: 95

Issue: 5

Appears on pages(s): 590-606

Keywords: beam-column joints; cyclic loads; earthquake loads; frames; headed reinforcement; joints (junctions); mechanical anchorage of reinforcement; standard hooks;

DOI: 10.14359/574

Date: 9/1/1998

Abstract:
The behavior and load-deformation response of reinforced concrete exterior and corner beam-column joints constructed with headed reinforcement is evaluated. The evaluation is based on the experimental results of two exterior and five corner joint specimens tested as part of an extensive experimental program. An overview of the experimental study is presented prior to evaluating the effectiveness of the specimens constructed using headed reinforcement. Use of headed reinforcement eased specimen fabrication, and concrete placement, and the behavior was as good as, or better than, similarly constructed specimens with standard 90 deg hooks. For beam-column corner joints, the test results indicate that additional transverse reinforcement is required at the heads to restrain pull-out of the head. For the exterior, interstory connections, excellent behavior was observed for specimens constructed to current design recommendations.