Improved seismic resilience of existing steel moment frame by built-in continuous columns

作者：Li, Cheng-Yu; Bai, Ru-Ning; Zhang, Hong-Tai^*; Jia, Liang-Jiu

来源：JOURNAL OF CONSTRUCTIONAL STEEL RESEARCH, 2023, 204: 107849.

DOI：10.1016/j.jcsr.2023.107849

• Continuous column
• Deterioration
• Stiffness
• Drift concentration
• Collapse control
• Seismic resilience

A seismic resilience strategy of retrofitting the existing columns of frame structures into built-in continuous columns (BCCs) hinged to the main frame is presented in this paper. The continuous columns provide vertical continuous stiffness to adjust the structural deformation distribution achieving collapse control. This study retrofits three 5-, 7-and 9-story prototype steel moment frames (SMFs) through external continuous columns (ECCs) or BCCs. In addition, effects of strength and stiffness deterioration on the seismic response of the SMFs are also considered. Results from pushover and incremental dynamic analysis show that the ECCs and BCCs can both mitigate structural displacement concentration. With a performance target of plasticity hinge ratio up to 50% for the main frame, when the stiffness demand is satisfied, the inter-story drift concentration factor of the BCC frame is always smaller than that of the ECC one. It indicates that the inter-story deformation distribution of the BCC frame is more uniform under the premise of satisfying the target collapse resistance performance.

• 单位
  同济大学