Reliability of Short Composite Beam‐Column Strength Interaction

Abstract

The strength of a short composite steel‐concrete beam column is affected by variations in the strengths of concrete and steel, the cross‐sectional dimensions of concrete and steel section, the placement of steel section and reinforcing bars, and the strength model itself. The effects of these factors on the variability of the ultimate strength of square short composite beam columns in which steel shapes are encased in cast‐in‐place concrete are studied. The results indicate that the specified concrete strength, the structural steel ratio, and the end eccentricity ratio influence the probability distribution properties of short composite beam‐column strength. The end eccentricity ratios of 0.5 or less are critical since they have a very significant effect on the beam‐column strength. As expected, the beam columns with slenderness ratios near the ACI Building Code upper limit for short columns produce lower strengths than the corresponding cross sections.