Bond Performance of Interior Beam-Column Joints with High-Strength Reinforcement

Four beam-column joint tests were undertaken to assess the accuracy of New Zealand design rules relating to bond strength in beam-column joints when applied to large diameter, high-strength reinforcement. The ratio of longitudinal beam reinforcement diameter to column depth intentionally did not meet the requirements of the New Zealand design standard for any of the units. The units were subjected to cyclic displacements up to interstory drift angles of 5%. Bond failure occurred in two of the four test units, at drift levels exceeding those allowed by international codes. It is believed that the unexpectedly good bond performance of the remaining two units was due to the large excess of vertical joint shear and column moment capacity. [PUBLICATION ABSTRACT]