الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
Thin-walled cold-formed steel structural members occupy an important part in the field
of modem structural engineering because of their low weight to strength ratio and their
ease of fabrication. Because of large width to thickness ratio of the component plates of
the cross-section, they are subjected to local buckling, overall buckling in addition to the
common yield failure criterion. Current design of cold-formed steel members, especiaJ1y
those having high slenderness ratio of cross section component elements, is basicall y
dependable on using the effective area of cross section based on von Karman approach.
This leads to a complexity of the design of cold-formed steel members.
Therefore, the main purpose of the present research is to investigate (experimentally and
theoretically), the influence of web depth-to-thickness ratio and web depth to flange
width ratio on the ultimate capacity of cold-formed thin-walled beam-columns. An
experimental program has been conducted on 15 box-section beam-column specimens
loaded axially up to failure. A parametric study was conducted, using the finite element
model, on a variety of thin walled box-sections representing columns, beams and beamcolumns.
The section ultimate capacities were determined and plotted in the form of
interaction curves. The results of the finite element model were used to develop design
equations to predict the ultimate strength of thin-walled box-sections subjected to pure
moment and or pure normal force. In the proposed approaches, designers need to
compute only the proposed buckling factor (:I<.”ooel) which takes into account web-flange
interaction and they have to use the total gross sectional area to find the ultimate strength
of columns, beams and beam-columns of thin walled box-sections.