Seismic performance evaluation and numerical analysis of CFDST long columns with local corrosion under eccentric compression

In this study, the seismic performance of locally corroded CST and CFDST long columns was evaluated by quasi-static tests. The effects of four levels of corrosion and two types of cross-sections on damage patterns, horizontal load-displacement curves, and seismic indexes were assessed. ABAQUS software was used to conduct extended simulations on long columns of CFDST, analyzing the impact of each parameter on seismic performance. Experimental results indicated that the horizontal load-displacement hysteresis curves of the CFDST long columns within the specified corrosion parameters exhibit robust characteristics, demonstrating improved seismic performance and energy dissipation capacity while preventing sudden damage due to local buckling. The parametric analysis showed that increasing the diameter-to-thickness ratio of the outer steel pipe and decreasing the hollow ratio significantly impact the peak load, whereas increasing the axial compression ratio and eccentricity results in non-uniform specimen damage and reduced peak load.