Design provision assessment for the resistance of laterally restrained cellular steel beams
Vitaliy V. Degtyarev, Stephen Hicks, Felipe Piana Vendramell Ferreira, Konstantinos Daniel Tsavdaridis
Abstract
This paper evaluates the accuracy and reliability of laterally restrained cellular beams designed according to SCI P355, EN 1993-1-13, and AISC Design Guide 31 (DG31). The evaluations relied on extensive numerical data developed within the study using FE models validated against test results. The reliability analyses followed EN 1990 Annex D for both SCI P355 and EN 1993-1-13, and AISI S100 Chapter K for AISC DG31. The improved Hasofer–Lind–Rackwitz–Fiessler (iHL–RF) reliability method was also used for all considered provisions. The results indicate that SCI P355 and EN 1993-1-13 predict the beam resistance reasonably well, while AISC DG31 produces higher mean and coefficient of variation values of the simulation-to-prediction ratios than the European provisions. Partial factors computed per EN 1990 Annex D exceeded 1.00 for many failure modes, but the iHL–RF method indicated that the partial factor of 1.00 is justified for all limit states except for web-post buckling determined according to EN 1993-1-13. These results demonstrate that the EN 1993-1-13 web-post buckling rules should be revised and the more onerous buckling curve c used in design. Whilst this proposed change may be considered controversial for such a new standard, buckling curve c has been widely used in design according to SCI P355 for 15 years. AISC DG31 produced conservative designs. The findings of this study highlight areas where the existing provisions need revision and provide insights on how the improvements can be made, thereby contributing to the safety and economy of this form of construction.