Title:
Seismic Behavior of Monolithic Exterior Beam-Column Connections with Unbonded Post-Tensioning
Author(s):
Sanghee Kim, Thomas H.-K. Kang, Donghyuk Jung, Byung Un Kwon, and Dong Joo Lee
Publication:
Structural Journal
Volume:
120
Issue:
6
Appears on pages(s):
49-62
Keywords:
cyclic test; exterior beam-column connection; high-strength concrete (HSC); joint shear demand; joint shear strength; monolithic connection; tendons; unbonded post-tensioning
DOI:
10.14359/51739085
Date:
11/1/2023
Abstract:
This paper presents experimental results on seismic behaviors of
post-tensioned (PT) monolithic exterior beam-column connections.
Lateral cyclic loading tests were carried out for six fullscale
exterior beam-column joint subassemblies fabricated with
normal- and high-strength materials. Despite substantial joint
cover spalling, the normal-strength specimens exhibited satisfactory
lateral strengths and hysteretic behaviors up to ±5% drift
ratios by virtue of the confinement effect of post-tensioning. The
high-strength PT specimens also showed stable hysteretic behaviors
with significantly reduced joint damages. It was found that the
post-tensioning can increase the joint shear strength by more than
60% in both types of specimens. Furthermore, the post-tensioning
was effective in retaining the lateral stiffness of the beam-column
joints under the repeated loads, especially in high-strength specimens, enabling them to maintain at least 90% of their first-cycle stiffnesses throughout the testing.
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