OpenSEES-Based Seismic Performance Analysis of CFRP-Reinforced Concrete Column

To address durability issues in concrete structures caused by steel corrosion， this study proposed replacing steel reinforcement with carbon fiber-reinforced polymer （CFRP） tendons and systematically investigated the seismic performance of CFRP-reinforced concrete columns. Through low-cycle reversed loading tests on three full-scale specimens and OpenSEES numerical simulations， the influence mechanisms of key design parameters—including axial compression ratio （ν）， concrete strength， shear span ratio （λ）， longitudinal reinforcement ratio （ρ）， and stirrup ratio （ρ_s）—were elucidated. The results demonstrated that a threshold effect of axial compression ratio （ν）， beyond which the risk of reinforcement yielding surged and seismic performance deteriorated abruptly； unlike strength degradation induced by excessive ν， enhanced concrete strength significantly improved load-bearing capacity and energy dissipation but exacerbated brittle failure； increased shear span ratio （λ） shifed failure modes toward flexural dominance， reducing load capacity while the linear-elastic constitutive behavior of CFRP tendons limited energy dissipation enhancement； higher longitudinal reinforcement ratio （ρ） boost load capacity， delayed yielding initiation and stiffness degradation， and improved energy dissipation； stirrup ratio （ρ_s） exerted negligible effects on lateral stiffness but maintained post-yield strength stability through enhanced core concrete confinement at elevated ratios.