Experimental analysis of the influence of weak/strong axis on rectangular ultra‐high strength concrete filled steel tubular slender columns subjected to eccentric loads

Key Points

• This research aims to investigate how the weak and strong axis influences the performance of slender rectangular tubular columns filled with ultra-high strength concrete under eccentric loads.
• Conducted eight experimental tests on rectangular tubular columns filled with ultra-high strength concrete.
• Applied a constant bending moment distribution while varying the axis (weak and strong axis).
• Maintained the same column section geometry, concrete, and steel specifications across tests.
• Analyzed the effects of eccentric action load and infill concrete on column performance.
• Observed varying ultimate loads based on the axis orientation under applied loads.
• Measured and discussed performance indexes including Strength Index (SI) and Concrete Contribution Ratio (CCR).
• Found significant differences in structural performance between weak axis and strong axis configurations.

Abstract