Eccentrically patch-loaded steel I-girders: The influence of patch load length on the ultimate strength

The ultimate strength of steel I-girders is reduced when the loads are applied at an eccentricity relative to the center of the section, compared with the centric case, for which the loads are applied in the plane of the web. Current expressions for the strength reduction coefficient for eccentrically patch-loaded steel I-girders do not account for the length of the patch loading. In this paper, the effect of patch load length is investigated using a substantially larger data set than was available in the past. The length of the patch load is found to have a significant influence on the strength reduction coefficient for small ratios of flange thickness to web thickness, tf/twtf/tw.