EXPLICIT APPROACH TO DESIGN OF STAINLESS-STEEL COLUMNS

The paper describes a design procedure for stainless-steel columns fai ling by flexural buckling. In the approach, the stress-strain curve is assumed to be expressed as a Ramberg-Osgood curve, defined in terms o f the initial modulus (E-0), the 0.2% proof stress (sigma(0.2)), and t he parameter n. It is shown that the column curve can be described in terms of the Ramberg-Osgood parameters by adopting a Ferry curve as th e basic strength curve, and expressing the imperfection parameter in t erms of E-0, sigma(0.2), and n. By using a Ferry curve, the design pro cedure is explicit. This contrasts with the iterative approach describ ed in the ASCE load and resistance factor design (LRFD) specification for the design of cold-formed stainless steel structural members. The proposed strength curves are compared with those from tests on stainle ss steel columns. It is shown that the coefficient of variation of the ratio of test strength to design strength is lower using the proposed design approach than when using the ASCE specification; thus, the pro posed approach is more accurate than that described in the ASCE specif ication. It is also more efficient because it is explicit. Using the c omparison with test results, the resistance factor to be used with the proposed design procedure is derived.