A Study on Web Buckling Analysis of Lipped Channel Sections and Z Sections With Web Holes

Abstract

Cold formed steel (CFS) beams are produced by generally by two methods namely, Roll forming and Break pressing. These members have a wide range of applications in Cladding panels and decking, Stud frames and other fabricated structures. Local wall thickness to height ratio causes cold formed steel sections to undergo local buckling. However the use of cold formed steel sections are increased now a days due to the improved post buckling behaviour. CFS sections with web openings are commonly used in floor joists or wall studs in industrial, commercial and residential buildings. Theses opening provide for building services causes reduction in the strength of the sections. In most of the CFS sections with web holes in them, channel sections are found to be used widely. Z sections are also used widely in this field, however no researches has been done in Z sections with the effects of web holes. IS811:1987, provides specifications for lipped channel sections and Z sections. This study mainly concentrates on a comparative study of the web buckling analysis of lipped channel sections and Z sections. Non-linear elasto plastic finite element analysis are used to study the effect of web holes on web buckling analysis under interior two flange loading conditions (ITF) and interior one flange loading conditions. This finite element model was then used for the parametric study on the effect of different size and position of web holes. Various codes were also used to study the effect of different size and position of web holes in the load carrying capacity of the section.