The design of cold-formed steel members must consider a variety of buckling failure modes, including local buckling, distortional buckling, and global buckling. In 2004, the American Iron and Steel Institute incorporated the Direct Strength Method (DSM) into the North American Specification for the Design of Cold-Formed Steel Members as an alternative to traditional design methods. This method involves an elastic buckling analysis to determine buckling modes and stresses, and utilizes a series of nominal strength curves for predicting member strength. However, the strength curve selection requires mode determination based on general guidelines and interpretation of mode shapes. The purpose of this paper is to present a newly developed quantitative method of determining buckling modes. This will allow the complete DSM strength calculations to be performed by computer software without user intervention, and will enable stronger adoption of the Direct Strength Method.
展开▼
