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AbstractWithin the Master’s course “Civil Engineering” at TU Darmstadt, a project has to be carried out. In the winter term 2018/2019 this was the design and fabrication of a bridge spanning 6 m and made entirely from paper. Students had to find bridge types suitable for the use of paper, develop and optimise cross sections and bracing systems and furthermore prove the load bearing capacity. This included the use of experimental methods explicitly. Finally, the bridge had to be erected crossing a small creek. No materials other than paper, cardboard and glue were allowed.

The urgency of effective climate action measures and the practical experience in the context of the existing European Emissions Trading Scheme (ETS) are striking arguments for the introduction of uniform prices on CO₂emissions: as a minimum price in the ETS and as a reform of existing tax rates on fossil fuels (CO₂tax) for heating and transport (Non-ETS). In order for CO₂pricing not to become a mere instrument of rising government revenues, the options currently under consideration are the counter-financing of existing taxes and levies that reduces electricity prices or a per capita refund (climate bonus) for households. Both result initially in very similar distributional effects: the lower the household income, the higher the initial financial relief. Compared to the counter-financing of the EEG levy, climate bonuses are expected to have stronger rebound effects and the reduction of bureaucracy and promotion of the efficient use of renewable energy in heating and transport (sector coupling) would be waived. Thus a counter-financing, in particular the EEG levy in order to lower electricity costs, is a priority. In order to adequately address social hardships, only few socio-political accompanying measures would be needed that are largely independent of the pricing mechanism.

In the past decades, structural fire design has changed essentially. In the past, the structural integrity of single elements was mostly proven by load tables that were based on fire tests. The introduction of the “hot” Eurocodes (Parts 1–2) offers the possibility to assess the resistance of even complex structural systems under fire conditions. For this purpose, a calculation can be made according to the Eurocodes taking into account the relevant material behavior, which is mainly known for structural steel and concrete elements. The material behavior is defined in the Eurocodes by stress–strain curves, depending on the temperature. Even for connections, design rules are given. The resistance of bolts in fire can easily be calculated using global reduction factors that depend on the member temperature. The global reduction factors for bolts are valid at present for all grades. Tests showed that either differing alloying materials or varying treatment methods can lead to a relevant change in the ultimate strength. These two points have an important influence on the production process of zinc-coated high-strength grade 10.9 bolts (fu= 1000 N/mm2). On account of this, tension tests on specimen and zinc-coated bolt assemblies have been conducted to assess the behavior under fire conditions. The results, on one hand, provide the possibility to verify the reduction factors for grade 10.9 bolts given in the Eurocode and, on the other hand, lead to a more precise understanding of high-strength bolt behavior under fire conditions. This paper describes the state of the art, the tests, and the present results of numerical analysis.

Steel concrete composite beams are an economical alternative for the construction of wide-spanned slender structures in parking lots, office and industrial buildings. They combine the tensile strength and stiffness of steel sections with the good compressive strength of concrete slabs. To ensure an unrestricted use of the building, the expected deformations, vibrations and cracks are calculated during the analysis of the serviceability limit state. In reality, major differences between the calculations and the real deflections of beams are observed. Therefore, the deflection behaviour of composite beams was analysed and recommendations were developed to improve the calculation of the deformations. The deflection history was measured continuously during construction of four parking lots built with steel concrete composite beams. One result was that the fabrication of the beams at the manufacturing plant has an important influence on the subsequent deflection of the beam.

A complete new fairground was built in Stuttgart just on the doorstep of the International Airport. Part of the fairground is a multi-storey car park. This car park is a steel and steel concrete composite construction with a total length of 440 m, a width of 100 m and a height of up to 22 m. It is positioned like a bridge over a very busy highway and a new railroad track for Germany's high speed train ICE. Due to the remarkable position it became the eye-catching landmark for the new fairground in Stuttgart.Due to the fact that the highway traffic should not be affected by the erection, the main parts of the construction were launched over the highway, while the traffic was still in full progress. More than 5,500 tons of steel and concrete structure where moved about 170 meters. With a speed of 6 m per hours, six separate moves were necessary to place the structure into the final position.The car park was opened to the public on June 12th 2007 and contains space for more than 4,000 cars. In September 2007 the construction company received the European award for steel structures 2007 for this extraordinary building. This paper describes the structure of the car park, the concept of the fire protection, an interesting detail and the erection of the structure.

Die Bestimmung der Tragfähigkeit von Bauteilen aus S 460 im Brandfall auf der Grundlage vereinfachter oder allgemeiner Berechnungsverfahren entsprechend EN 1993‐1‐2 [1] erfordert die Kenntnis der mechanischen Eigenschaften des hochfesten Feinkornbaustahls unter erhöhten Temperaturen. Hierzu wurden Untersuchungen an Probestäben aus einem normalisierend gewalzten S 460 N und einem thermomechanisch gewalzten S 460 M durchgeführt. Beide Stahlsorten unterscheiden sich sowohl in ihrer chemischen Zusammensetzung als auch in der Temperaturführung beim Walzen. Auf der Grundlage instationärer Warmkriechversuche wurden Werkstoffgesetze für den Temperaturbereich von 20 bis 900 °C hergeleitet. Die Untersuchungen zeigen eine im Vergleich zu S 460 N erhöhte Festigkeit des S 460 M bei hohen Temperaturen. Diese ist zurückzuführen auf die durch das thermomechanische Walzen verursachte Verfestigung und die Verringerung der Kriechgeschwindigkeit durch Niob‐ und Titanausscheidungen. Beim Vergleich der Ergebnisse mit den in EN 1993‐1‐2 [1] für S 460 angegebenen Werkstoffgesetzen erkennt man, dass diese sowohl die Festigkeit als auch die Steifigkeit des untersuchten S 460 N überschätzen.

Die Lehrveranstaltung “Produktionsverfahren im Stahlbau” der Technischen Universität Darmstadt wird seit zwei Jahren parallel zur Präsenzveranstaltung auch online angeboten. Externen Studierenden ist es somit möglich, an der Veranstaltung teilzunehmen, ohne daß sie in Darmstadt präsent sein müssen. Diese Umstellung ist ohne größere Eingriffe in die bestehende Lehrveranstaltung möglich gewesen und trotz beschränkter Ressourcen mit großem Erfolg umgesetzt worden.

Clustering large data sets is a central challenge in gene expression analysis. The hybridization of synthetic oligonucleotides to arrayed cDNAs yields a fingerprint for each cDNA clone. Cluster analysis of these fingerprints can identify clones corresponding to the same gene. We have developed a novel algorithm for cluster analysis that is based on graph theoretic techniques. Unlike other methods, it does not assume that the clusters are hierarchically structured and does not require prior knowledge on the number of clusters. In tests with simulated libraries the algorithm outperformed the Greedy method and demonstrated high speed and robustness to high error rate. Good solution quality was also obtained in a blind test on real cDNA fingerprints.

In the centre of Frankfurt the office building "Junghof" had to be refurbished to make it attractive for modern use. When it was built in the 1950s five storeys were located around a central court. The new concept (Fig. 1) developed by the Architects and Engineers added two storeys, raising the building above the critical height into the class of high-rise buildings. This led to additional requirements with regard to the fire-safety, mainly escape routes and fire resistance of structural elements.The building is located close to a district with many sky scrapers that rise up to 200 m. Because it is visible from most of these the architects invested much effort into the 5th façade. The roof was given a free form, cladded with aluminium panels.