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

Abstract The paper describes eight experimental tests conducted on rectangular tubular columns filled with ultra‐high strength concrete and subjected to a constant bending moment distribution with respect to the weak and strong axis. The test parameters were the eccentric action load, and the axis considered. All the columns have the same section geometry, were prepare with the same concrete and steel and have the same slenderness. These tests complete previous works carried on by the research group. The influence of the infill concrete and the eccentricity applied are analyzed in depth. The ultimate load and different performance indexes such as Strength Index (SI) and Concrete Contribution Ratio (CCR) were considered in the discussion.