Experimental investigation on the tensile behaviour of welded RHS high strength steel X-joints

The newest version of prEN 1993-1-8 (2022) prescribes a material factor (Cf) to reduce the design resistance of welded joints made of high strength steel (HSS) mostly due to the lack of available experiments, given the less ductility of HSS compared to mild steel. Additionally, it is stated that the material design yield strength should not...

Equivalent material properties of the heat-affected zone in welded cold-formed rectangular hollow section connections

A welded connection consists of three main material zones, the base material (BM), the heat-affect zone (HAZ), and the weld metal (WM). The strength of HAZ depends on the BM grade and manufacturing process, electrode grade, and welding parameters. Under certain conditions, HAZ has the lowest material strength, especially for high-strength...

A method for determining the constitutive model of the heat-affected zone using digital image correlation

The heat-affected zone (HAZ) is an unmelted region of a welded joint that has changed in material properties because of high temperatures during the welding process. HAZ has a lower strength than the base (parent) material (BM) and the weld metal (WM). The lower material strength is more significant if BM is made of high strength steel and...

Fracture simulation of welded RHS X-joints using GTN damage model

A welded rectangular hollow section (RHS) X-joint exposed to tension loading has three typical fracture-related failure modes: Punching shear failure (PSF), Brace failure (BF), and Chord side wall failure (CSWF). Prediction of these failure modes by finite element (FE) simulations requires modelling of the material damage. An appropriate...

Experimental and numerical investigations on the structural performance of mild and high strength steel welded RHS X-joints

Higher strength steels (HSS) hollow sections with steel grades from S460 up to and including S700 are becoming increasingly competitive in long span structures. Reduction of self weight is accomplished with the smaller wall thickness of the hollow section, leading to fabrication, transport and execution benefits. The use of HSS has a positive...