The cross-sectional configurations, manufacturing processes and fabrication practices of cold-formed steel structural members differ in several respects from those of hot-rolled steel shapes. For cold-formed steel sections, the forming process is performed at, or near, room temperature by the use of bending brakes, press brakes or roll-forming machines. Some of the significant differences between cold-formed sections and hot-rolled shapes are-(a) absence of the residual stresses caused by uneven cooling due to hot-rolling;(b) lack of corner fillets;(c) presence of increased yield strength with decreased proportional limit and ductility resulting from cold forming;(d) presence of cold-reducing stresses when cold-rolled steel stock has not been fully annealed;(e) prevalence of elements having large width-to-thickness ratios and, hence, subject to local buckling in compression;(f) rounded corners; and(g) stress-strain curves can be either sharp-yielding type or gradual-yielding type.AS/NZS 4600 (Standards Australia/Standards New Zealand, 1996) is limited to the design of steel structural members cold-formed from carbon or low-alloy sheet, strip, plate or bar. The design is to be in accordance with the limit states design method.The Standard is applicable only to cold-formed sections not more than 25 mm in thickness. Research conducted at the University of Missouri-Rolla (Yu, Liu, and McKinney, 1973b and 1974) has verified the applicability of the Standard's provisions for such cases.In view of the fact that most of the design provisions have been developed on the experimental work subject to static loading, the Standard is intended for the design of cold-formed steel structural members to be used for load-carrying purposes in buildings. For structures other than buildings, appropriate allowances should be made for dynamic effects. The Standard does not apply to the design of structures subject to fire or fatigue since insufficient data was available on these phenomena for cold-formed members during its preparation.
Important note : All end users must be registered with an Account prior to user licenses being assigned.