Seismic Safety and Post-Earthquake Resilience of Frame with Debonded High-Strength Reinforced Concrete-Encased-and-Filled Steel Tubular Columns

The incremental dynamic analysis of a ten-floor frame archetype whose concrete encased-and-filled steel tubular (CEFST) columns with debonded high-strength reinforcements (DHSRs) was performed. Seismic fragility results showed the use of DHSR is beneficial for the seismic safety of CEFST frame system, especially for the prevention of seismic collapse. The utilization of CEFST columns with DHSRs in the first three stories alone introduced a small probability of seismic damage. The fragility curves of residual story lateral drifts indicated the use of DHSR can significantly mitigate the residual deformation. Precise evaluation of residual drift of frame structure should be further studied.