Behaviour of cold formed steel stiffened web sections

Abstract

Steel is a worldwide construction material, which is a combination of Iron and Carbon. There are two types of steel sections; one of the sections is Cold Formed Steel (CFS) section, which are used mainly in lightweight building applications. Features of CFS are lightness, high strength and stiffness, mass production and easy erection, economy in transportation and handling, non-combustibility, recyclable material. The advantages of CFS are that the yield strength of the steel is increased in cold forming due to the consequence of cold work into strain - hardening range. The predominant zones were increased where the metal is bent by folding. The effect of cold working is thus to enhance the mean yield stress by 15% - 30%. The yield stress may be enhanced by a minimum of 15%. The needs for this research were due to high industrial activity in recent years, usage of steel in the construction activity was increased tremendously. Recently, CFS was utilized more to deduce the cost of construction. The most common shape for CFS members is a lipped channel, although Z , C , tubular , hat , sigma and other shapes have also been used. Since all the advantages of the sigma shape are not effectively utilized, this project is focused on the behaviour and strength characteristics of the sigma section. The thesis has been arranged in five chapters as follows: A brief introduction about the details of CFS, its manufacturing process, existing features, the advantages of existing materials, different flexural members, and the stiffeners. Then the literary review of the various methods with their corresponding techniques about the evaluation and the system. After completion of the survey, Finite Element Software ANSYS 14.0 were employed. Totally, 12 specimens are used by assuming two boundary conditions with open and closed distortional buckling restraint around the edges for analysis. Then, ABAQUS v6.4. were employed. Then, 108 specimens of different geometry and profile shapes were analysed. From this analysis, vertical de