Experimental and numerical study on impact behaviour of concrete-filled steel tubular flange girders with local corrosion

Abstract

The lateral impact behaviour of concrete-filled steel tubular flange girders (CFSTFGs) with local corrosion was investigated in this study. Lateral impact tests on 18 girders were completed, and the effects of the local corrosion degree, impact height, impact number, and specimen type were considered. The damage development, failure modes, impact force, midspan deflection, reaction force, and energy absorption were analyzed. The tested results indicated that the CFSTFGs mainly experienced overall bending deformation under lateral impact, while the girder with corroded web and flange had the lowest impact resistance. As the local corrosion degree increases, the plateau impact force gradually reduces while the maximum deflection increases of girders. The peak and plateau stages of the impact force become more noticeable as the impact number increases. Then, a finite element analysis (FEA) model of CFSTFGs with local corrosion under lateral impact was developed and calibrated. The full-range analysis of impact responses of a typical CFSTFG with local corrosion was carried out, including the impact process, bending moment development, force balance, and plastic deformation energy. The key parameters affecting the impact force, midspan deflection, and dynamic bending moment of CFSTFGs were also discussed. The simplified method was finally proposed to calculate the dynamic flexural capacity of CFSTFGs with local corrosion under lateral impact.