Title: Experimental Study on Hysteretic Behavior of Concrete- Filled Square Carbon Fiber-Reinforced Polymer Steel Tubular Beam-Column
Author(s): Qing-li Wang, Kuan Peng, Yi-Huan Guo, and Yong-bo Shao
Publication: Structural Journal
Appears on pages(s): 67-80
Keywords: finite element simulation; hysteretic behavior; middle section lateral force-deflection curve; square carbon fiber-reinforced polymer (CFRP) concrete-filled steel tube
To study the hysteretic behavior of concrete-filled square carbon fiber-reinforced polymer (CFRP) steel tubular (S-CF-CFRP-ST) beam-columns under different influence factors, 12 specimens were designed, and the failure mode, middle section lateral force-deflection (P-Δ) curve, middle section bending moment-curvature
(M-ϕ) curve, and middle section deflection-deformation (Δ−Δ′) curve were studied. Using the axial compression ratio and longitudinal CFRP reinforcement coefficient as influencing factors, the effects of the axial compression ratio and longitudinal CFRP reinforcement coefficient on the P-Δ skeleton curve, M-ϕ skeleton curve, strength and stiffness degradation, ductility, cumulative energy consumption, and other indexes were studied. The P-Δ curve and deformation mode of the specimens were simulated by ABAQUS, and the effects of the axial compression ratio, slenderness ratio, and other main parameters on the hysteretic performance of the members were studied. The test results show that CFRP has good lateral restraint and longitudinal reinforcement effect on concrete-filled steel tubular (CFST) columns, and the local buckling of CFST is delayed. The P-Δ curve and M-ϕ curve of all specimens
are full. In addition, the steel tube and CFRP have good synergy in both longitudinal and transverse directions. The change of the axial compression ratio and longitudinal CFRP reinforcement coefficient has no significant effect on the strength degradation. The increase of the axial compression ratio and longitudinal CFRP reinforcement coefficient can improve the flexural capacity and stiffness of the specimens, and slow down the stiffness degradation, but reduce the ductility and cumulative energy consumption of the specimens. The finite element software ABAQUS is used to simulate the P-Δ curve and deformation mode of the specimens. It is found that the simulation results are in good agreement with the experimental results. Based on the model analysis of the main parameters, it is found that the increase of steel yield strength and CFRP layers can improve the bearing capacity of the specimens, and the axial compression ratio has the most significant effect on the specimens.