Scholarlink

<p>In reinforced concrete (RC) moment frames, beam-column joints are critical to seismic performance, yet ordinary concrete joints often exhibit poor behavior under cyclic loading. This study presents a novel experimental investigation into retrofitting deliberately weakened RC beam-column joints using Ultra High Performance concrete (UHPC) jackets. Unlike previous studies that examined UHPC in general strengthening applications, this work uniquely evaluates three distinct jacketing configurations (applied to column-only, partial beam-column, and connection-zone regions) under two weakness scenarios: weak beam-strong core and strong beam-weak panel zone. Five specimens were tested under cyclic displacement-controlled loading with a constant axial load of 300 kN. The results demonstrated that UHPC jacketing significantly enhanced seismic performance: the ultimate load capacity increased by up to 2.6 times (from 70.2 kN in the weakest specimen to 181.7 kN in the strengthened specimen), energy dissipation improved by up to 2.5 times, and specimens achieved ductile behavior with drift ratios exceeding 4%. Among the tested configurations, covering both the panel zone and adjacent beam-column regions (Model S4) proved most effective in improving strength, stiffness, and energy dissipation while confining damage to replaceable UHPC layers. These findings experimentally validate UHPC jacketing as an effective and practical retrofitting strategy for enhancing the seismic resilience of vulnerable ordinary RC beam-column joints.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Improving the behavior of RC beam-to-column connection using ultra high performance concrete jacket

  • 期刊论文

  • 发表日期：

    2026年4月10日

查看全文
  • Ramtin Rezakhani,
  • Mohamad Ghasem Vetr,
  • Ali Ghamari

摘要

In reinforced concrete (RC) moment frames, beam-column joints are critical to seismic performance, yet ordinary concrete joints often exhibit poor behavior under cyclic loading. This study presents a novel experimental investigation into retrofitting deliberately weakened RC beam-column joints using Ultra High Performance concrete (UHPC) jackets. Unlike previous studies that examined UHPC in general strengthening applications, this work uniquely evaluates three distinct jacketing configurations (applied to column-only, partial beam-column, and connection-zone regions) under two weakness scenarios: weak beam-strong core and strong beam-weak panel zone. Five specimens were tested under cyclic displacement-controlled loading with a constant axial load of 300 kN. The results demonstrated that UHPC jacketing significantly enhanced seismic performance: the ultimate load capacity increased by up to 2.6 times (from 70.2 kN in the weakest specimen to 181.7 kN in the strengthened specimen), energy dissipation improved by up to 2.5 times, and specimens achieved ductile behavior with drift ratios exceeding 4%. Among the tested configurations, covering both the panel zone and adjacent beam-column regions (Model S4) proved most effective in improving strength, stiffness, and energy dissipation while confining damage to replaceable UHPC layers. These findings experimentally validate UHPC jacketing as an effective and practical retrofitting strategy for enhancing the seismic resilience of vulnerable ordinary RC beam-column joints.