Improved Design Rules for Stainless and Carbon Steel Bolts Loaded in Tension and Shear

The design of non‐preloaded bolted connections as bearing type connections (category A), tension connections (category D) or bearing type connections subjected to tension and shear loading (categories A + D) is given in EN 1993‐1‐8 for carbon steel bolts. However, the design of these kinds of bolted connections made of stainless steel is given in EN 1993‐1‐4 mainly basing on those regulations developed for carbon steel bolts neglecting the specific material properties of stainless steel bolts. To overcome this lack of knowledge, experimental and numerical investigations as well as reliability analyses were systematically carried out for austenitic and duplex stainless steel bolts on their tension, single‐shear and their interaction resistance. Finally, more economical and harmonised design rules for stainless steel bolts could be developed and implemented in the revision of EN 1993‐1‐4 and the German technical approval abZ/abG Z‐30.3‐6:2022. Subsequently, the regulations covered in EN 1993‐1‐8 for carbon steel bolts were checked, considering already existing experimental results in literature and new test results carried out by the authors regarding the applicability of the newly developed rules for stainless steel bolts. As a result, it was found that the rules for carbon steel bolts can be improved, being in line with the newly developed rules for stainless steel bolts and meeting the Eurocode safety requirements.