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The Direct Strength Method (DSM) of design,which is an alternative to the Effective Width Method (EWM) used for cold-formed steel structural design,has recently been adopted by some design codes (NAS,2004 Supplement;AS/NZS4600,2003) for the design of cold-formed steel structural members.The DSM as used in the NAS and AS/NZS 4600 has been limited to cold-formed beams and columns.Till now the method has not been applied to hot-rolled and welded steel structural members.Furthermore,even for beam-columns of cold-formed sections there exist no DSM formulas either for in-plane stability or for out-of-plane stability.Welded Ⅰ-section beam-columns with slender web are designed by the EWD to the current Chinese Standard GB 50017-2003 (Code for Design of Steel Structures).The DSM is much simpler to apply than the EWM as it uses gross section properties rather than effective section properties as commonly used in EWM.Due to this simplicity to use,the question naturally arises:if the DSM can also be used to such members.In this paper this possibility is preliminarily explored for such sections both for in-plane and out-of-plane stability and it is concluded that based on the GB 50017-2003,the DSM was found to give rather good design accuracy compared with the current EWM for most cases discussed and it is much easier to implement,therefore a set of design proposals based on the GB 50017-2003 is put forward.