Compression Capacity Prediction of Cold-Formed Steel Sections

Cold-formed steel sections have important advantages such as flexible cross sectional
profiles and high strength-to-weight ratio but constantly experience buckling
problems. They are currently designed based on Effective Width philosophy in the
BS, Euro, American and Australian codes. The Direct Strength Method is a new
design philosophy utilizing the buckling loads obtained from a buckling analysis.
This project aims to investigate the feasibility of using the Direct Strength method
especially when employing the sections available in Malaysia industry. The local
steel designers are not well exposed to this method and no study has been reported on
its use in local industry. Activities of the project include data gathering, column
buckling analysis using Cornell University Finite Strip Method (CUFSM) and
comparison of ultimate strength based on test values and applications of Direct
Strength method and Effective Width method. Compression testing on Bluescope
Lysaght sections Cl5015, Cl5019, Zl5015 and Zl5019 of 500 mm and 1000 mm
length were carried out and were analyzed. Comparison with test results shows good
agreement with the theoretical values predicted using Direct Strength method. This
method can be a good compression capacity predictor because it explicitly
incorporates all buckling modes, does not require calculations of effective properties
and gives reliable predictions.