Performance-based damage quantification and evaluation for self-centering concrete frames

Abstract

Self-centering concrete frames (SCCFs) are designed to provide superior seismic capacities with resilient features. Although a well-designed SCCF can limit damage development, it still impairs post-earthquake performance and shall be considered properly. Quantifying and evaluating structural damage can provide valuable guidance for seismic designs and post-earthquake assessments, yet related studies towards SCCFs are still limited. This paper aims to conduct damage quantification and evaluation for SCCFs. The damage development and distribution within SCCFs are investigated. A modified damage model is adopted to quantify the damage developed in beam-column joints. Weighting coefficients based on the hysteretic energy demands are introduced to assess story and integral structural damage. 12 SCCFs with different structural features are designed and analyzed under 44 ground motions. The damage development within structures is quantified and evaluated using the performance-based damage intervals. The results show that damage developed in SCCFs exhibit stable growth with seismic intensities, implying superiorities in the damage controllability and stability. Meanwhile, increasing the self-centering parameter λ proves effective in reducing damage developed in SCCFs. A method to estimate integral structural damage is proposed, while proper design parameters are suggested to further assist seismic designs for SCCFs based on analytical results.