Shear Verification of Plain and Lipped Channel Steel Sections

Resumo

With the continuous growth of industrialization in the construction sector in recent years, steel structures have become increasingly common and economically viable. Along with this trend, the use of cold-formed steel sections has also expanded. Made from thin steel sheets, these sections offer advantages such as low weight, ease of fabrication, handling, and transportation, thereby reducing assembly and shipping costs.In steel roofing structures, cold-formed sections—particularly plain and lipped channel sections—are widely used in trusses and purlins. When used as purlins, these members are subjected to oblique bending, with loads applied outside the shear center of the cross-section—a condition not accounted for in the current Brazilian steel design standards.Given this context, the present study analyzes the maximum shear stresses in the webs of plain and lipped channel sections subjected to the boundary conditions and loading typically experienced by roof purlins. The analysis is carried out using an analytical method based on solid mechanics, the approach recommended by Brazilian steel design codes, and the finite element method (FEM), in order to validate the analytical results.In addition to comparing the results obtained from the three different methods, this work proposes a correction factor to align the results from the Brazilian design codes with those derived from solid mechanics, in cases where discrepancies are found.