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The present paper is a contribution to the discussion on the over-strength coefficients of structural steels. In addition to the statistical scatter of the yield strength, the dependence of the material properties on the loading speed and on repeated loading up to the inelastic range must be taken into account here, among other things, for earthquake designs.

The Northern Elbe Bridge, built in 1963, is the eastern Hamburg Elbe crossing of the Federal Motorway 1 over the Norderelbe, which gives the bridge its name, and is located directly between the two motorway junctions Hamburg-Süd and Hamburg-Südost. After the first damage in the form of fatigue cracks occurred in the 2010s, recalculations and inspections were carried out. In the course of this, it was determined that a mathematical structural modelling that corresponds as closely as possible to reality is of great importance in order to be able to assess the damage that has occurred and reliably determine critical points in the structure. For this purpose a comparison between measurement and calculation of the structural deformations under defined loads offers a good possibility for verification and calibration of calculation models. In the present case the crossings of exceptional heavy transports with defined loads could be used. An innovative kinematic laser scanning was used for the metrological recording of the structural deformations. The principle procedure for the measurement data acquisition and the results of the comparison are described in this article.

The new Zayed University Campus in Abu Dhabi is a successful example of international cooperation between designers and builders from multiple continents, the potential of the main contractor philosophy and the benefits from BIM-equivalent design approaches. Besides extreme time constraints, the project required mastery of numerous engineering challenges, different design philosophies, difficult interfaces between design and construction works as same as a huge construction site with up to 8,000 workers running in parallel to the design works. 

Using modern planning and fabrication methods whilst employing innovative materials resulted in a complex and highly precise geometry in the production of the free-form sculpture Virtual Tectonics 1. The project met all of the highest requirements for stability and sustainability and the sculpture is entirely fit for purpose. As a symbol for the possible applications of fibre composite materials especially of CFRP and GFRP) in the building construction industry, the experiences gained and lessons learned in the course of the project are a sound foundation for the further development of entire structures made from fibre composite materials.

The second part of the report about Hall 3A focuses on distinctive features in the detailed design and the erection on site, regarding the aspects of geotechnics, concrete and steel construction.

The construction work can be divided into two parts: the just in time design of the foundation slab due to sophisticated subsoil conditions and the challenging, heavily reinforced and complex concrete structures of the jointless edge wing with exposed concrete of highest quality stand for the first part.

The second part focuses on the filigree steel construction and the thoroughly detailed design for all building stages, as there are: calculation of the stress free three dimensional presetted fabrication geometry, numerous, exceptional and complex states of construction and temporary erection stages.

The Nuremberg fairground will be extended southwards. From 2014 on, visitors and exhibitors of the world-famous Toy Fair will be able to enjoy the new Hall 3A designed by Zaha Hadid Architects. Already during the initial architecture study of 2010, the need for an exceptional architecture was determined, with the prerequisite to be affordable and feasible in the provided tight time window. Due to this and the technical complexity, the requirement of an interdisciplinary and fully 3D-based approach was given. For structural engineering numerous challenges did exist, primary within development and analysis of the architecturally exposed steel structure of the roof with spans of more than 75 m. Already during the early structural design phases, the construction sequence had to be taken into account. Additionally, the solid construction works of the approximately 105 m long, joint-less edge wing as well as for the connection to the existing Hall 4A got ambitious due to architecturally exposed concrete along with complex geometries. The mixed foundation with large bore piles in the hall area in combination with a slab foundation for the edge wing, the needs for a large building pit adjacent to a main municipal sewer and its subsequent superstructure led to geotechnical engineering challenges as well.

Using modern planning and fabrication methods whilst employing innovative materials resulted in a complex and highly precise geometry in the production of the free-form sculpture Virtual Tectonics 1. The project met all of the highest requirements for stability and sustainability and the sculpture is entirely fit for purpose. As a symbol for the possible applications of fibre composite materials especially of CFRP and GFRP) in the building construction industry, the experiences gained and lessons learned in the course of the project are a sound foundation for the further development of entire structures made from fibre composite materials.

The HafenCity University (HCU) was founded on 01.01.2006 as a new University of the Built Environment and Metropolitan Development combining the four faculties of Architecture, Structural engineering, Geomatics and Urban planning. Situated directly on the River Elbe, the new building in the new HafenCity district offers space for some 1.400 students and180 staff as well as diverse central facilities consolidated on a gross floor area of about 30 000 square metres. The design by architects code unique reflects the special character and core competencies of the HCU. The sculptural, jointless structure in reinforced concrete frame construction is divided into two above-ground wings with a length of over 100 meach, connected by a central atrium as well as the shared single-storey plinths floor (so-called “Warftsockel”) designed as flood protection. The central foyer is enclosed by the filigree steel constructions of the atrium roof as well as the west and east façades. In particular the wide spans and distinctive projections, the practically complete visibility of the jointless concrete construction, the oblique angles of the building’s wings in themselves and in relation to each other, as well as the diversity of utilisations stacked on top of one another, demanded innovative solutions for the structural engineering. Additional challenges were presented by the all-round restrictive characteristics of the site, the tight budget, as well as the complexity of getting agreement on the building target among all parties concerned – taking into account a particular demand for sustainability – and the largely parallel building activities necessary due to scheduling reasons.

Part 2 of the report describes the planning and execution of the main structure for the new HafenCity University. Especially the constructive features of the wide-span COBIAX-slabs and the long cantilevering sections, the complexity of vertical load due to the multitude of crosswise wall-like beams, the filigree steelwork of the foyer and the special technical equipment for university laboratories will be reported. Finally same specials of construction sequence and temporary works concerning the above mentioned specifies will be described.

Along with the development of an exclusive office- and business building with four underground parking levels an about 13 m deep excavation pit with diaphragm walls and natural bottom sealing was needed. Considering the sensitive neighbouring buildings only little deformation of the underground was acceptable. By using a pre-stressed inner framework as upper bracing and a partial concrete cover as lower bracing the requirements were fulfilled. Already during preliminary design calculated ground deformations could be approved by an extensive measuring program accompanying the project.

The new Zayed University Campus in Abu Dhabi is a successful example of international cooperation between designers and builders from multiple continents, demonstrates the potential of the main contractor philosophy and showcases the benefits from BIM-equivalent design approaches. Apart from the extreme time constraints, the project required mastery of numerous engineering challenges. It required an understanding of different design and construction philosophies, management of difficult interfaces between design and construction works and consideration of the demand of a construction site with up to 8,000 workers running in parallel to the design works. Together with the employees and students of Zayed University, the main contractor and the architects, we are happy that our shared goal could be achieved in such a short time.

The new Zayed University Campus in Abu Dhabi is a successful example of international cooperation between designers and builders from multiple continents, the potential of the main contractor philosophy and the benefits from BIM-equivalent design approaches. Besides extreme time constraints, the project required mastery of numerous engineering challenges, different design philosophies, difficult interfaces between design and construction works as same as a huge construction site with up to 8,000 workers running in parallel to the design works.

Die Bebauung der Ericusspitze mit der neuen Zentrale des Spiegel-Verlages und mit dem Ericus-Contor ist ein gelungenes Beispiel für die frühe Bildung eines schlagkräftigen Teams aus Investoren und Planern und zugleich für das städtebaulich-architektonisch moderne wie nachhaltige Bauen. Neben zahlreichen Besonderheiten des Baugrundstücks waren dabei immerhin ein Investorenwettbewerb, ein internationaler Architektenwettbewerb, ein Bebauungsplanverfahren, eine aufwendige Planungs- und Vergabephase mit unzähligen Beteiligten, eine in die laufende Planung zu integrierende Nachhaltigkeitszertifizierung, ein Architektenwechsel, ungewöhnliche Aufgabenteilungen in der Planung sowie eine Großbaustelle mit zahlreichen ingenieurtechnischen Herausforderungen und terminlich bedingten Schnittstellen zu meistern.

Die dreiseitig vom Wasser umschlossene Ericusspitze ist nach wechselvoller Geschichte heute das nordöstliche Tor zum neuen Stadtteil HafenCity. Der dort neu angesiedelte Hauptsitz des Nachrichtenmagazins „Der Spiegel“ ist mit 15 Obergeschossen zudem einer der bedeutenden Hochpunkte der HafenCity. Zusammen mit dem benachbarten Ericus-Contor, dessen 11 Obergeschosse ebenfalls überwiegend als Büro genutzt werden, konnte ein architektonisch hochwertiges Ensemble mit Vorbildcharakter auch für das nachhaltige Bauen geformt werden. Beide Gebäude stehen auf einem gemeinsamen zweigeschossigen Warftsockel in fugenloser WU-Bauweise, der wesentlich zur Integration in das historische Umfeld beiträgt. Für die bereits sehr frühzeitig einbezogene Tragwerksplanung waren seit der Investorenauswahl und des internationalen Architektenwettbewerbes besondere technische und terminliche Herausforderungen zu meistern. Insbesondere tiefe Vor- und Rücksprünge in der Kubatur des Spiegel-Verlages und weitgespannte Brückengeschosse im Ericus-Contor erforderten ungewöhnliche Lösungen. Dies galt auch für die Pfahlgründung, bei der zahlreiche Zeitzeugen im Untergrund und neu eingebrachte Verpressanker aus einer parallel durchgeführten Sanierung und Ertüchtigung der das Grundstück einfassenden alten Kaimauern sowie eine außergewöhnliche terminliche Situation zu berücksichtigen waren. Die große Baugrube direkt am tideoffenen Elbwasser konnte durch enge tragwerksplanerische Vorgaben z. B. zur Höhenentwicklung des Rohbaus und unter Ausnutzung der örtlichen Gegebenheiten ohne umlaufenden Spundwandkasten und ohne aufwendige Wasserhaltung kostengünstig realisiert werden.

Many infrastructure projects at the moment include the planning of shallow tunnels to be bored with a shield machine. The extent of the settlement trough with the resulting settlement and inclination of buildings often represent an important problem. Calculations of these deformations are based on an empirical approximation process or finite element methods. The reliability of a FE calculation relies significantly on the quality and calibration of the material model used. A material model with a universal approach for all soils, whose parameters can be determined very simply from standardised laboratory tests, has been developed as a contribution to this problem. The practicality of the material model has been demonstrated in a multitude of specialised civil engineering projects where no damage occurred, and where the calculations performed at the design stage were confirmed by measurements during the construction phase. The process is illustrated through the example of construction projects in Hamburg. The geology there is characterised by Pleistocene and Holocene sands as well as mica silt, illite and till of varying consolidation resulting from preloading during ice ages.

The unexpected severe damages which earthquake-engineered steel structures suffered from the earthquakes of Northridge 1994 and Kobe 1995 remind of structural mild steel´s rate-dependency. Due to lack of relevant knowledge for earthquake-loading the rate-dependency of mild steel was investigated within a DFG-financed research. Major results are presented below. Both for monotonic and repeated inelastic loading structural mild steel shows significant dependency of stress-strain-relation from loading speed. Relaxation and creep phenomena at room temperature result from the materials rate-dependency. For use in FEA a constitutive model is presented, which is based on longtime DFG-financed research and can describe the complex material behaviour of structural mild steel in total.

The unexpected severe damages which earthquake-engineered steel structures suffered from the earthquakes of Northridge 1994 and Kobe 1995 remind of structural mild steel´s rate-dependency. Due to lack of relevant knowledge for earthquake-loading the rate-dependency of mild steel was investigated within a DFG-financed research. Major results are presented below. Both for monotonic and repeated inelastic loading structural mild steel shows significant dependency of stress-strain-relation from loading speed. Relaxation and creep phenomena at room temperature result from the materials rate-dependency. For use in FEA a constitutive model is presented, which is based on longtime DFG-financed research and can describe the complex material behaviour of structural mild steel in total.

The prediction of the realistic lifetime and the prolongation of the service life of a structure is an important task to reduce costs. The usual theoretical predictions are not very reliable. The prediction model used consists of a load model, a system-transfer model and a damage model. The results of these sequentially coupled models are usually unreliable, especially the influence of the uncertain load and damage models controls the reliability of the result. A method based on monitoring strategies is presented, which avoids these problems. If the remaining life time of existing structures should be assessed, information about the strain time history of the past is needed. It is shown how these data can be generated.