Experimental investigations of T‐joints made of high‐strength square hollow sections

This article presents experimental investigations on welded T-joints made of high-strength square hollow sections (S700MH and S890QH) under axial and bending loads, with and without preloading the chord. A total of 56 tests were conducted to analyse the influence of geometric parameters, material properties and pre-tensioning on joint behaviour and failure mechanism. The results are evaluated statistically and compared with current and draft Eurocode provisions (prEN 1993-1-8). The findings confirm that while the Cf-factor offers a conservative basis, refinements are necessary to account for distinct failure mechanism such as punching shear failure and the influence of loading direction, particularly for high-strength steels.