Effectiveness of Horizontal Stirrups in Joint Core for Exterior Beam-Column Joints with Nonseismic Design

摘要

Reversed cyclic-load tests on full-scale reinforced concrete exterior beam-column joints with nonseismic design to the British standard BS 8110 were carried out. The seismic behaviour of these non-seismically designed beam-column joints was investigated, and the effectiveness of horizontal stirrups in joint core on the seismic performance and shear strength of the joints were emphasised. It was found that horizontal stirrups which were provided in beam-column joints with nonseismic design improve effectively the seismic behaviour and enhance the joint shear strength. It was shown that the upper limit of the horizontal stirrup ratio in join core for enhancing the shear capacity of exterior beam-column joints was 0.4%, which may be considered as one of the design criteria of joint stirrups for non-seismically designed exterior beam-column joints under low-to-moderate earthquakes. Additional transverse reinforcement provided to the joint may thus have less effect on the enhancement of the joint shear strength.