Effect of web inclination on the behavior of cold formed steel C-purlins

Abstract EN

C and Z sections are two of the most common cold-formed steel shapes in use today.

In case of portal frames those sections are used as purlins that carry loads not parallel to their webs, which lead to stresses in both major and minor directions of the sections.

To effectively use those sections the webs are made to have the same inclination angle as for the portal frame rafter.

A comparison between the behavior of C-purlins having vertical and inclined webs has been made to show the effect of web inclination on the capacity of the C-purlins.

The members selected are widely used in practice and have (h / t) that varies from 60 to 123.

The thicknesses of the used C-purlins are 1.5, 2.0, 2.5 and 3.0 mm.

The height of the used sections are 200 and 250 mm.

30 sections have been studied to show the effect of the web inclination angle on the behavior of the C-purlins.

The web slope varies from 0 to 20 %.

The direct strength method has been used to compare the local, distortional and overall buckling stresses for C-purlins having vertical and inclined webs.

Results are discussed and recommendations are given for the use of the C-purlins having inclined webs.