Numerical Investigation on Web Crippling Behaviour of Cold-formed C-section Beam with Vertical Stiffeners

Abstract

Present paper investigates an efficiency of application of vertical stiffeners in the web of cold-formed C-section beams under local concentrated loading. The stiffeners would be cold-formed – an I-section cut is made on the web and the cut edges are folded into the inner side of the profile. A lipped channel beam with a length of 1 m was selected to investigate the efficiency of vertical web stiffeners. As a validation of rational stiffener parameters requires an extensive experimental program that is time-consuming and prohibitively expensive, thus, the numerical modelling using finite element method (FEM) was adopted. The numerical modelling was performed according to the standardized methodology of American Iron and Steel Institute (AISI) covering four loading and boundary conditions: 1) interior-one-flange (IOF); 2) interior-two-flange (ITF); 3) end-one-flange (EOF); and 4) end-two-flange (ETF). The influence of stiffeners geometry on the ultimate stiffened web crippling strength was assessed using the data from the numerical modelling of one hundred specimens. The obtained results were compared to the ultimate web crippling capacity of unstiffened beams. The relationships of load-vertical web displacement and load-horizontal web displacement were derived. The analysis of the obtained results formulated the directions for a further research.