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There are many examples of steel structures subjected to severe environmental conditions with bolted connections directly exposed to climatic agents such as steel bridges, mining transfer towers, wind towers etc. In this experimental research, non‐slip joints with M16 and M20 bolts have been studied. The specimens were subjected to fourteen 12 h freeze‐thaw cycles, with periodic immersion in water and temperature oscillation. Subsequently, the connections were subjected to a slip test under monotonic load. The results were compared with other equal joints not subjected to freeze‐thaw cycles and kept at room temperature for the same time. Some interesting conclusions are extracted from this piece of research. It was observed that freeze‐thaw cycles negatively affect the slip resistance of non‐slip joints with GB+ZE surfaces, even with a slight increase in clamping force. Samples with SR and GB surfaces increase in their slip resistance was observed. [ABSTRACT FROM AUTHOR]

Fortunately the design processes of steel buildings across Europe is eventually covered by a unified code: The Eurocode 3: 'Design of steel structures.' Nevertheless, although Eurocodes will soon become mandatory documents, designs will not be standardized because each country has a set of National Annexes which must be taken into account when designing in that particular country. Furthermore, every country also has its own body of non-conflicting complementary information. A problem then arises when engineers need to produce designs in other European countries, either for a company based in one state or as individuals. Also, allowing engineers time out of the office for attendance at the intensive training courses which are required for earning experience on the new codes of design, frequently represents an obstacle for their employers. In an attempt to solve these problems, a strong trans-national partnership has been working to develop an ICT-supported, flexible training approach to allow designers to apply Eurocodes in accordance with the national regulations and practices of different member states. The resulting material in seven languages shows how to design a typical building according to the different national contexts. The developed portal incorporates facilities for course presentation, forums, blogs and on-line translation. The students thought that the portal was an effective tool that helped them to improve the quality and efficiency of their studies. In their opinion the web-course is well structured and they found the forum for discussion and the web-based tutoring system very helpful. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 448-458, 2013 [ABSTRACT FROM AUTHOR]

The use of adhesively bonded carbon fiber reinforced polymer (CFRP) materials to reinforce cracked steel elements has gained widespread acceptance in order to extend the lifespan of metallic structures. This allows an important reduction of the stress intensity factor (SIF) at the crack tip and thus a significant increase of the fatigue life. This paper deals with the assessment of the SIF for repaired cracked steel plates, using semi-empirical analysis and finite element analysis. Metallic plates with only one crack originating from a center hole were investigated. Virtual crack closure technique (VCCT) was used to define and evaluate the stress intensity factor at crack tip. The obtained modeling results are compared with experimental investigations led by the authors for different reinforcement configurations including symmetrical and non-symmetrical reinforcement, normal modulus and ultra-high-modulus CFRP plates, and pre-stressed CFRP plates. Results show that finite element model (FEM) analysis can obviously simulate the fatigue performance of the CFRP bonded steel plates with different reinforcement configurations. Moreover, a parametric analysis of the influence of the pre-stressing level was also conducted. The results show that an increase of the pre-stressing level results in an increase of the fatigue life of the element. [ABSTRACT FROM AUTHOR]

The successful and effective shaping of curvilinear steel bar structures is becoming an increasingly complex and difficult task, due to the growing demands to satisfy both economic and environmental requirements. However, computer software for algorithmic-aided design makes it possible to take into account many aspects affecting structures, as early as the initial design stage. In this context, the paper presents an optimization method for shaping the curvilinear steel bar canopies of hyperbolic paraboloid and cylindroid shapes, in order to obtain effective structures adapted to external environmental conditions. The best structural solutions in terms of the structure's shape, topology and support positions are obtained as the effects of multi-criteria optimizations with the application of genetic algorithms. The following are used as the optimization criteria: minimal structure mass and minimal deflections of the structure's members, as well as their maximal utilization. Additionally, the best canopy locations in relation to the sides of the world are determined through analyzing their shadow casts for various locations, so the structures have the least impact on the surroundings. This research, with its interdisciplinary character, aims to present the possibility of applying generative shaping tools to obtain structurally effective and environment-adaptive curvilinear steel bar structures in the first phase of their design, which can support sustainable designing. [ABSTRACT FROM AUTHOR]