Statistical Analysis of Slender Composite Beam‐Column Strength

Abstract

The strength of a slender composite steel‐concrete beam column differs from the computed nominal value, which is based on specified nominal strengths of constituent materials, geometric properties, and code design equations. The variability in the strength is caused by the variations in the strengths of concrete and steel, the cross‐section dimensions of concrete and steel sections, the placement of steel sections and reinforcing bars, and the strength model itself, among other factors. This study was undertaken to investigate the variability of ultimate strength of slender composite beam columns in which steel shapes are encased in cast‐in‐place concrete. The results of this study indicate that the slenderness ratio, the structural steel ratio, and the end eccentricity ratio significantly influence the probability distribution properties of slender composite beam‐column strength, whereas the effect of specified concrete strength seems to be significant only for beam columns with a low slenderness ratio.