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Abstract: General design concept for buckling structures – Suggestion for a new part F of EN 1993‐1‐5. A revised version of EN 1993‐1‐5 should soon be published. The reduced stress method will be reworked in section 10. The complementary regulations published recently in this journal, in particular to the biaxial pressed stiffened steel plate, are partly time‐consuming. In addition to these announced rules a concept with „gradual exactness” with which a low limit value of buckling resistance can be fast determined is applied in the code proposal. A new reduction factor is defined for stiffeners, based on an already published proposal for the geometrical imperfection amplitude. Because of the compatibility to the MNA/LBA concept in EN 1993‐1‐6, the suggestion for a new part F of EN 1993‐1‐5 can be used generally for compound steel structures in future. Examples are given for application of the code proposal. [ABSTRACT FROM AUTHOR]

Abstract: Failure of a steel pallet rack in Athens. Pallet racking systems have peculiar characteristics which differ from usual steel structures that make them sensitive to stability failure modes. In the present paper a rack failure is presented where the rack has failed due to lateral torsional and distortional buckling of its most stressed uprights. The structural behavior was studied by a combination of experimental and numerical/analytical methods. The investigations included test loading, bending tests on pallet beams, compression tests on stub column and bending tests on beam end connectors. Subsequently, a global geometrical non‐linear analysis is performed on the 3‐D system. Its results indicate by comparison with the pictures of the actual structure that the collapse mode is correctly detected. Conclusions are drawn that recommend the performance of static and dynamic analyses on an obligatory basis. [ABSTRACT FROM AUTHOR]

Abstract: Calculation of corrugated wall sheet silos. Corrugated wall sheet silos are one of the most constructions of storing agricultural products. Until the introduction of the DIN EN regulations in 2010 the calculation and the design performance of these corrugated wall sheet silos were carried out essentially according to DIN 18914: 1985‐09. This standard has been canceled without replacement and has been replaced by DIN EN 1993‐4‐1 and other regulations according to DIN EN. The complexity of the ”new“ norms is well known. It is reported on the experience how the simple design and calculation concept of the silo container can be implemented relatively simply within the very extensive DIN EN regulations. [ABSTRACT FROM AUTHOR]

Transversal load introduction into unstiffened girder webs – interaction with shear force and bending moment and implementation in new Eurocode version Transversal load introductions into unstiffened girder webs are often used economic solutions in building structures, not directly covered in the current Eurocode. Within this paper an engineering design model, developed at TU Graz, is evaluated for cases with additional high shear forces and bending moments acting at the girder. The resulting load carrying behaviour, in cases of interaction between Fz & Vz & My, is presented, based on comprehensive numerical studies, also for girders which are susceptible to web buckling. Finally, the modified design model is presented, which will be part of the new Eurocode version prEN 1993‐1‐1. In addition, a more general solution is shown, which could also be implemented in the Eurocode in form of a national Annex. [ABSTRACT FROM AUTHOR]

Abstract: Introduction of the Direct Strength Method into the design of cold formed steel members according to EN 1993‐1‐3. Cold formed steel members have a varied area of applications in steel lightweight constructions but are subject to local and global instabilities due to compressive and bending stress. The design method of the European Standard EN 1993‐1‐3 is based on the Method of Effective Widths covering local and distortional buckling. Unfortunately, an EN 1993‐1‐3 design is time‐consuming and prone to errors, furthermore the results are often conservative. This paper is going to introduce a new, practical design method for cold‐formed steel sections that combines the established European regulations of global instabilities with the Direct Strength Method (DSM) described in the North American standard AISI Standard 100 regarding local stability analysis. Based on comparative studies of mono‐symmetric cross‐sections it is possible to demonstrate that this new method offers a great potential of improving the design of cold‐formed sections, additionally improves the economic efficiency of lightweight steel sections. More theoretical and experimental investigations are needed, deeper leading questions are to answer, until this method is able to supplement the European standard. [ABSTRACT FROM AUTHOR]

Abstract: Equivalent initial imperfections for applying the partial internal forces method for flexural buckling about the weak axis. This paper compares design approaches for equivalent initial imperfections of steel members with hot‐rolled double symmetric I‐/H‐profiles subjected to buckling about the weak axis. In addition to the normative rules applied in Germany and Europe, design approaches for imperfections are also taken into account, which are currently discussed as part of the further development of Eurocode 3. A proposal using the partial internal forces method allows a consistent design for steel members taking into account the cross‐sectional failure as well as the flexural buckling about the strong and weak axis. The proposal leads to design results that agree well with the results of numerical simulations. [ABSTRACT FROM AUTHOR]

Abstract: The use of High Strength Steel (HSS) S690 in highway bridge decks is not yet widespread. A research program investigated the optimal use of HSS in bridges. A comparative design was performed for a 21.5 m wide highway bridge, with a typical 80 m long inner span and a steel‐concrete composite twin plate girder deck, using the Eurocode standards. Three designs were produced: Design (A) with S355 NL steel grade, Design (B) with HSS S690 QL/QL1, and Design (C), also with HSS S690, but exploring different design options provided by welded joint treatments to improve fatigue and suggest possible enhancement of the present Eurocode rules. General guidelines for the design of highway bridge decks using HSS S690 are provided. [ABSTRACT FROM AUTHOR]