Experimental and Theoretical Research on Welded Aluminum K-Joints ^†

Aluminum alloys provide corrosion resistance, lightweight construction, and functionality through extruded profiles. The creation of heat-affected zones (HAZs), which can reduce load-bearing capacity by up to 50% and complicate K-joint design, makes it difficult to apply aluminum in truss systems. Since EN 1999-1-1 (EC 9) does not even provide guidelines for welded aluminum K-joints, practitioners turn to EN 1993-1-8 (EC 3), resulting in a conservative design that ignores the advantages of aluminum. This study investigated the behavior of welded K-joints in lattice girders made of alloy EN AW 6082 T6. The comparison of the experimental and numerical results showed different load-bearing behaviors depending on dimensions and cross-section types. Further tests were carried out. The aim was to derive an aluminum-specific design procedure.