Abstract
The seismic performance of a corner beam-column joint in reinforced concrete frames was studied by testing two three-dimensional corner beam-column subassemblage specimens without slabs under constant column axial load and bi-directional lateral cyclic load reversals. The column-to-beam flexural strength ratio was varied from 1.4 to 2.3 by changing the magnitude of column axial load. Although a sufficient margin to prevent shear failure was provided to a corner beam-column joint in the test, the subassemblage specimens failed in joint hinging after beam and column longitudinal bars and joint hoops yielded. The ultimate joint hinging capacity of a corner joint under bi-directional lateral loading was enhanced by an increase in column compressive axial load, and can be estimated based on the new mechanism proposed by Kusuhara and Shiohara.
Highlights
A new mechanism of joint hinging was proposed by Shiohara [1], a professor at the University of Tokyo, Japan, for a beamcolumn joint in reinforced concrete (RC) moment-resisting frames
(1) a joint shear capacity margin of 1.6 estimated by Architectural Institute of Japan (AIJ) seismic provisions was provided to a corner beamcolumn joint in the test to prevent shear failure, all joints failed by joint hinging under bi-directional lateral cyclic loading after beam and column longitudinal bars and joint hoops yielded
(3) Peak story shear force in the transverse direction under bidirectional loading was 0.74 times the ultimate beam flexural capacity computed by a section analysis for a corner beam–column subassemblage with a column axial stress ratio of 0.04
Summary
A new mechanism of joint hinging was proposed by Shiohara [1], a professor at the University of Tokyo, Japan, for a beamcolumn joint in reinforced concrete (RC) moment-resisting frames. The seismic performance of a corner beam-column joint in RC frames was studied, focusing on joint hinging mechanism, by testing two three-dimensional beam-column subassemblage specimens without slabs under both constant column axial load and bi-directional lateral cyclic load reversals. Beam longitudinal reinforcement was mechanically anchored by an end plate, using a headed bar, within the joint core concrete with a horizontally projected length of 300 mm corresponding to 0.86 times the column depth. The column-to-beam flexural strength ratio for specimens varied depending on the direction of lateral load due to the asymmetrical position of beam bars in a beam section and varying axial load in a lower column which was caused by change of a direction of beam shear force. Strains of beam and column longitudinal bars and joint hoops were measured by strain gauges
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call