Load-bearing and deformation behaviour of truss joints using thin-walled pentagon cross-sections

For medium and large spans of trusses efficient solutions can be achieved with members made of cold formed sections due to the easiness of production and the nearly unlimited variety of cross-section types and the high-strength steels available today. The use of ‘pentagon’ cross-sections with a large radius of gyration for both axes offers statical and constructional advantages for the chords. The low-cost design of the truss joints using a gusset plate welded onto the ridge of the cross-section can lead, however, to great section deformations and consequently also to an early failure of the entire construction. This local load-bearing behavior can be described by the following analytical calculation model based on the Generalized Beam Theory (GBT). Furthermore this analytical model has been compared with tests on truss segments and results of an numerical analysis using the finite element program system ABAQUS.