Numerical Studies of Rivet-Fastened Rectangular Hollow Flange Channel Beams

The rivet-fastened rectangular hollow flange channel beam (RHFCB) is a new cold-formed hollow section proposed as an alternative to welded hollow flange beams. It is a monosymmetric channel section made by rivet-fastening two torsionally rigid rectangular hollow flanges to a web plate. This method will allow the designers to develop optimum sections, with affordable rivet connection between their web and flange elements. In addition to this unique geometry, the rivet-fastened RHFCBs also have unique characteristics relating to their stress-strain characteristics, residual stresses, initial geometric imperfections and hollow flanges that are not encountered in conventional hot-rolled and cold-formed steel channel sections. Therefore detailed experimental and numerical studies were conducted to study the section moment capacities of rivet-fastened RHFCBs. This paper presents the details of the numerical study of rivet-fastened RHFCBs and the results. Finite element models of rivet-fastened RHFCBs were developed by including all the significant effects that influence their ultimate section moment capacities, including material inelasticity, and geometric imperfections. The results from finite element analyses were then compared with corresponding experimental results and the predictions from the current design rules. Test results showed that the developed finite element models were able to predict the behaviour and section moment capacities of RHFCBs. The validated model was then used in a detailed parametric study that produced additional section moment capacity data of the rivet-fastened RHFCBs