Out‐of‐Plane Buckling Assessment of Frames through Overall Stability Design Method: Fid-Bau Portal

Out‐of‐Plane Buckling Assessment of Frames through Overall Stability Design Method

Papp, Ferenc / Szalai, József / Majid, Movahedi R.

ABSTRACTThis article extends the innovative Overall Stability Design Method (OSDM) for steel portal frames with double symmetric I and H cross‐sections. The OSDM utilizes linear buckling analysis and equivalent initial geometrical imperfection in the shape of buckling mode for the assessment of out‐of‐plane buckling resistance. The method was developed for single structural members with two alternative procedures. One of them is the overall imperfection method which uses equivalent amplitude and the other is the overall strength reduction method which follows the classic reduction factor based procedure. Both methods have been validated for fundamental cases of lateral‐torsional buckling and coupled flexural and lateral‐torsional buckling of individual members published recently. In this article these methods are extended for portal frames. The method may be adapted by any commercial design software which is able to execute a relevant transmission of the displacements (namely the warping) through the applied frame corner joints. The overall validation of the method for portal frames needs considerable investigations. This article aims to do the first step by the presentation of the procedure through benchmark examples.