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Wind from all directions Wind loads on membrane structures are not regulated by standards. The variety of shapes of the typically open and thus flow‐exposed surfaces on both sides cannot be captured using geometric variables in tables, as is common for typical building forms in Eurocode EN 1991‐1‐4. The recommended individual wind tunnel tests are only feasible for larger projects with the corresponding budgets and planning periods. Therefore, some recommendations for typical membrane roofs have been collected in the literature, and at the same time, computer‐based wind simulations have developed to the extent that they are now also offered in market‐standard FEM software packages. This paper aims to explain the accuracy and comparability of the various approaches using case studies. The paper presents the analysis of standard approaches, literature values, wind tunnel tests, and computer‐based methods with a comparison of calculation results and provides insights into the development of load assumptions in membrane construction. [ABSTRACT FROM AUTHOR]

Translation abstract Linking nano with macro – opportunities for steel constructionNanostructured metallic multilayers have significantly higher strength, fatigue resistance and ductility than monolithic homogeneous metal cross sections. The superior structural properties of these nanostructured cross sections are known, and so it is surprising why no attempt has been made to date to use nanostructured cross sections in macro cross sections in structural engineering to improve the cross section properties. This paper links the advantages of nanostructured multilayers with the needs of homogeneous metallic macro‐cross sections and examines the question of the extent to which the high‐performance material nanolaminate can compensate for the structural weak points of metallic infrastructure. The following weak points of metallic infrastructure are addressed: 1) the welded connection subjected to fatigue and corrosion, 2) additively printed metallic cross sections exposed to fatigue and corrosion. The article provides food for thought on how nanostructured multilayer can potentially contribute to the future of steel construction. As an example, the design and maintenance of cyclically loaded metallic infrastructure structures, such as bridges and offshore wind turbines, are discussed and it is shown how sustainability, resource conservation, reduction of the CO2 footprint, availability, security of supply and economic viability of steel infrastructure structures can potentially be achieved. [ABSTRACT FROM AUTHOR]

Structural stability tests on two‐span channel members in bending, axial compression and torsion The use of slender steel members promotes the competitiveness of steel structures in structural engineering. However, these members often necessitate stability verifications. Global research activities in this field have so far mainly focussed on single‐span members with doubly symmetric cross‐sections. For mono‐symmetric sections such as channels, only a few design models exist based on experimental evidence. Moreover, the potential of structural systems such as multi‐span members is yet not entirely exploited in the normative verification models. Therefore, this paper presents a comprehensive experimental study on the stability behaviour of two‐span members with steel channels under combined loading. Five‐point bending tests were conducted to determine the load‐bearing capacities and to experimentally analyse the influence of the constructional detail of the central support, the axial load, the slenderness ratio and other parameters on the load‐bearing behaviour. The article provides the scientific basis for extending the scope of the stability verification for members subjected to bending, axial compression and torsion in Annex C.2 of the novel EN 1993‐1‐1:2022 to two‐span channel members. [ABSTRACT FROM AUTHOR]

Load‐bearing and fatigue behaviour of butt welds in plates of different thicknesses The cross‐section of long‐span steel structures is usually adapted to the bending moment distribution. For this purpose, a thickness transition is applied in the area of butt‐welded joints in flanges of I‐shaped beam members. The fatigue behaviour of these constructional details is complex and differs from a butt‐welded joint in steel plates of the same thickness. This paper presents the results of 30 notch detail tests and compares the behaviour of butt‐welded joints in plates with a thickness transition with those of the same thickness. The statistical analysis of the experimental studies shows a higher fatigue resistance for butt‐welded joints with a thickness transition compared to butt welds of plates of the same thickness. The classification of the latter constructional detail in detail category 90 acc. to FprEN1993‐1‐9:2024 can be confirmed. The prognosis of the notch detail tests with the Two‐Stage‐Model confirms its applicability for the analytical‐numerical prediction of the service life of complex welded constructional details. In addition, the application of the model proves the influence of the thickness ratio and stress ratio on the service life of butt‐welded joints with thickness transition. [ABSTRACT FROM AUTHOR]