标题：Equivalent Stabilizing Force of the Simply Supported Roof Girders Including the Longitudinal Variability of the Compression Force Acting in the Restrained Chord
摘要：In the calculation model of the equivalent stabilizing force qd for bracing system consistent with EN 1993-1-1 it has been conservatively assumed that the member to be restrained is uniformly compressed within its length by an axial force. This assumption is incorrect owing to the actual distribution of the axial force which is non-uniform in the shape of parabola. Thus a different imperfection force is generated in comparison with this given in EN 1993-1-1. In the paper the equivalent stabilizing force qd of simply supported roof girders has been analyzed. The formulas for an equivalent stabilizing forces of restrained roof girders with parabolic variability of axial force, have been proposed. Obtained results have been discussed and illustrated with examples.
关键词：steel structures ; lateral bracing system ; equivalent stabilizing force ; roof girder ; member to be restrained ; purlin
