关键词: PVA-FRCC, 柱, 抗震性能, 损伤模型, 破坏形态, 变形, 耗能

Abstract: The pseudo-static test of 7 PVA-FRCC medium-length columns (hereinafter PVA-FRCC columns) was carried out with the shear span ratio, reinforcement ratio, and axial compression ratio as the research variables, and the crack morphology, deformation, energy consumption, and laser damage resistance of PVA-FRCC medium-length columns under seismic action were investigated. The results show that PVA-FRCC columns exhibit excellent crack control ability and closure ability after unloading, as well as remarkable ductility, deformation, and energy consumption capacity, with a maximum elastic-plastic limit displacement angle of 1/13. Specimens with higher shear span ratios have lower bearing capacity, while the reinforcing effect of PVA fibers endows superior deformation resistance and damage resistance after peak load. Furthermore, an increasing of reinforcement ratio leads to improve bearing capacity, deformation, and damage resistance of the PVA-FRCC columns, while an increasing of the axial compression ratio significantly reduces deformation, energy consumption, and damage resistance of specimens. PVA-FRCC columns with a smaller axial compression ratio and an appropriate shear span ratio and reinforcement ratio exhibit optimal performance when the PVA fiber volume fraction is 1%. To evaluate the damage status of PVA-FRCC columns, an improved Park-Ang damage model is proposed, which well satisfies the boundary conditions and reflects the trend of damage development which consistent with experimental results.

Key words: PVA-FRCC, column, seismic performance, damage model, destruction form, deformation, energy consumption