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Translation abstract Bridge rehabilitation by means of UHPC overlays in AustriaThe rehabilitation and integralisation of the Steinbach Bridge on the motorway network between Vienna and Graz is Austria's first project using the method of strengthening by an UHPC overlay. As unique features, the bridge was neither sealed nor equipped with an additional wearing surface. Thus, the 7 cm thick, structurally effective UHPC layer works as water barrier and as carriageway surface. Experience from this pilot project has been incorporated into the UHPC guideline of the Austrian society for Construction Technology, both in terms of construction and design. In this article, the relevant key topics such as bond strength between UHPC and existing concrete, both statically and in terms of fatigue, crack widths, construction joints and surface grip are treated in more detail. The behaviour as well as the performance is presented by means of experiments. Design rules derived from those experiments are shown using the project Steinbach Bridge as an example. A closer look at the condition of the Steinbach Bridge after more than ten years of intensive use completes the picture of this still young but already well‐developed method of construction, which is now regulated by the guideline. [ABSTRACT FROM AUTHOR]

Throughout history, bookbinding incorporated advancements in techniques, usage of a wide range of materials, and application of imaginative designs. Lacquered bindings are just one of several technical breakthroughs attributed to Persian artisans. They consist of a sophisticated structure of numerous layers. This study explores each layer and their materials and methods, including motifs used from the Safavid to Qajar periods. Moreover, various treatments used for each layer during manufacture as well as various methods for preparing paper pasteboards, including marqaš, ṭalāyi, tah ṭalāyi, zarak, dūdī, and abrī have been investigated through literature research and reconstruction. The intricate layer combinations used in Persian lacquered bindings cause several simultaneous chemical processes. Chemical, physical, and biological degradation are significantly influenced by raw materials and the original manufacturing process. Separation of layers, softening, yellowing and loss of transparency, cracking, hazing, and pigment as well as metal corrosion brought on by internal and external deterioration factors including light, temperature, and relative humidity will also be covered in this study. [ABSTRACT FROM AUTHOR]

Summary This article describes the importance of metal oxide materials for semiconductor technology, sensor technology, and renewable energies. By the utilization of new material systems and the specific properties of molecular metal oxides, large improvements in energy efficiency and performance can be expected in the future. However, the growing need for raw materials and of their exploitation harbors some global ecological and social conflict potential. The aspects such as recycling and environmental sustainability will continue to gain in significance. [ABSTRACT FROM AUTHOR]

In the present work, oil-in-water (O/W) emulsion systems were prepared by using the PEG-7 lauric acid glycerides as the emulsifiers and the liquid paraffin as the oil phase. The influence of processing parameters such as emulsification temperature, stirring speed, emulsifier concentration, oil-water volume ratio and polymer addition on the stability of the emulsion systems was investigated. In order to determine the optimal conditions for the preparation of the emulsion systems based on PEG-7 lauric acid glycerides, a laser drop size analyser and a rotational rheometer were used. As the stability of the O/W emulsion systems increased, the average droplet size of the O/W emulsions measured by the laser droplet size analyser became smaller and the viscosity, storage modulus and loss modulus of the O/W emulsions measured by the rotational rheometer became larger. The following optimal conditions were determined in this study: emulsification temperature 808C, stirring speed 500 r/min, emulsifier concentration 5 wt%, oil-water volume ratio 1:1 and added amount of xanthan gum 0.2 wt%. The droplet morphology of the O/W emulsion prepared under the optimal conditions, which was characterised by a super high magnification microscope, is small. Furthermore, the long-term stability of the emulsion system prepared under the optimal conditions was investigated over a period of time (4 weeks). The O/W emulsion proves to be well stable even after 4 weeks, with a water separation rate of 0%. [ABSTRACT FROM AUTHOR]

Cell salvage is an efficient method to reduce the transfusion of homologous banked blood, as documented by several meta-analyses detected in a systematic literature search. Cell salvage is widely used in orthopedics, trauma surgery, cardiovascular and abdominal transplantation surgery. The retransfusion of unwashed shed blood from wounds or drainage is not permitted according to German regulations. Following irradiation of wound blood, salvaged blood can also be used in tumor surgery. Cell salvage makes a valuable contribution to providing sufficient compatible blood for transfusions in cases of massive blood loss. Certain surgical procedures for Jehovah's Witnesses are only possible with the use of cell salvage. Another possible use is the washing of homologous banked blood, e. g. to prevent potassium-induced arrhythmia or sequestration of autologous platelets. Other advantages besides a good compatibility are the high vitality and functionality of the unstored autologous red blood cells. These have been declared a pharmaceutical product by the German transfusion task force in 2014, so that the autologous red blood cells are now under the control of the Pharmaceutical Products Act (AMG). The new hemotherapy guidelines, however, tolerate cell salvage only under strict rules, whereby the production of autologous blood during or after surgery is still possible without additional special permits. The new guidelines now require the introduction of a quality management system for cell salvage and regular quality controls. These quality controls include a control of the product hematocrit for every application, monthly controls of the protein and albumin elimination rates and the erythrocyte recovery rate for each cell salvage device. Testing for infection markers is not required. The application of cell salvage has to be reported to the appropriate authorities. [ABSTRACT FROM AUTHOR]

Large bar diameters and high reinforcement ratios – Part 3: Columns The use of large bar diameters and high reinforcement ratios can lead to columns with minimized cross‐sections. These columns provide great technical and economic potential, e.g. in the construction of high‐rise buildings, as the installation of technical building equipment can be simplified and the rentable effective area can be maximized. However, the use of such columns is limited due to a lack of experimental evidence and by existing standard regulations. In order to investigate the practical aspects of constructing, the load‐bearing capacity and the robustness of such highly reinforced columns, experimental and numerical investigations on normal strength reinforced concrete columns with large bar diameters and high reinforcement ratios were conducted at the iBMB, Division of Concrete Construction of the TU Braunschweig. The present paper describes the tests and presents the experimental and numerical results. [ABSTRACT FROM AUTHOR]

Abstract: Tightness of sandwich constructions – Water and air tightness in longitudinal joints and window connection joints. The air and water tightness of the envelope play an important role in the planning of modern buildings due to the ever increasing requirements in terms of energy conservation. For sandwich structures, which contain many joints due to the prefabricated elements, the design of these joints is of particular interest. In addition to the normative specifications regarding the joint tightness of sandwich panels, this report also explains the associated laboratory test procedures. Subsequently, the results of experimental and numerical investigations of various research projects are presented and conclusions for the production and assembly of sandwich elements are shown. All in all, it can be stated that very tight building envelopes can be realized with sandwich panels while observing important basic rules in production and assembly. [ABSTRACT FROM AUTHOR]

Sandwich Elements Made of UHPC and Foamed Polyurethane Modern building envelopes are sustainable and integral building constructions, which conserve resources, hold favourable physical properties, carry loads, are modular and feature a high freedom of design. Innovative sandwich constructions with concrete facings can meet this demands. The combination of high performance concrete and corrosion resistant reinforcement made of fibre-reinforced polymers for the outer layers in combination with foamed in pack polyurethane as core material can lead to efficient sandwich elements. The production method is tested with planar sandwich beams and sandwich plates in the first step, which additionally are the basis for sandwich elements with various cross-sectional shapes. The test results are presented within this paper. [ABSTRACT FROM AUTHOR]

Light-weight precast shell elements made of textile reinforced concrete: production, experimental investigations and application potential For single curved barrel-vault shells made of textile reinforced concrete (TRC) a manufacturing process has been developed that comprises the production of the precast parts as well as tailored solutions for transport and mounting of the filigree shells at the construction site. Furthermore, the load-bearing capacity of the shells could be verified experimentally using large-scale tests of prototypes. Saw cuts document the high production quality of the precast parts.The developed methods were successfully applied within the research project by constructing a large-scale roof structure consisting of five barrel-vault shells. The cross-sectional thickness of the 10 m2 large elements amounts to only 2 cm emphasizing the high strength and application potential of TRC. [ABSTRACT FROM AUTHOR]

Stahlfaserbeton wird seit Jahrzehnten in verschiedenen Bereichen des Bauwesens erfolgreich eingesetzt. Hauptsächlich kommt Stahlfaserbeton aber in Form von Industriefußböden zur Anwendung. Die großen Streuungen in den Materialkennwerten erschweren die Anwendung für Bauteile mit nennenswerten Beanspruchungen. Daher wurden umfangreiche experimentelle Untersuchungen zur Streuung des Zugtragverhaltens von Faserbeton durchgeführt. Diese beinhalten 4-Punkt-Biegezugversuche an großformatigen Balken sowie an Standardbiegebalken nach DAfStb-Richtlinie Stahlfaserbeton. Die Balken unterscheiden sich in verwendetem Fasergehalt und -länge sowie nach der Art der Faserzugabe. Nach Durchführung der Biegezugversuche wurde entlang der Balken die Faserorientierung und -verteilung mit dem fotooptischen Verfahren bestimmt. Die Ergebnisse zeigen, dass die Faserverteilung stark streut, während die Faserorientierung nur in geringem Maße schwankt. Sowohl in den Biegezugversuchen als auch in der Auswertung der Schnittbilder ist der Einfluss der Faserzugabeart feststellbar. Die Streuung im Tragverhalten kann durch eine geeignete Faserzugabe und folglich homogenere Faserverteilung reduziert werden. Influence of fibre addition on the scattering in the post cracking tensile behaviour of steel fibre reinforced concrete Steel fibre reinforced concrete (SFRC) has been successfully used in certain areas of concrete constructions. However, the main area of application remains industrial concrete floor slabs. The large scattering in the material properties impedes the application for components with significant loads. Therefore, extensive experimental investigations on the scattering in the tensile post cracking behaviour of SFRC were carried out. The investigations include 4-point-bending tests on large-sized beams as well as standardized beams according to the German guideline for fibre concrete. The specimens differ in fibre amount, fibre length and type of fibre addition. After bending tests, the fibre orientation and distribution were determined along all specimens by using an opto-analytical method. The test results demonstrate that the fibre orientation is almost constant, while the fibre distribution scatters significantly. In bending tests as well as the opto-analytical analysis, the influence of the type of fibre addition is evident. Consequently, the scattering in the mechanical behaviour can be reduced by a suitable fibre addition and thus a more homogeneous fibre distribution can be gained. [ABSTRACT FROM AUTHOR]

Über die Havel verläuft in Rathenow eine neue 350 m lange Brücke für Fußgänger und Radfahrer. Die S-förmige Weinberg-Brücke war das zentrale Highlight der Bundesgartenschau 2015 in der Havelregion. Die Gartenschau fand im Land Brandenburg in den Städten Brandenburg/Havel, Premnitz, Rathenow und Rhinow/Stölln sowie in Havelberg in Sachsen-Anhalt statt. Die Brücke besteht aus zwei Bogenbrücken, der eine führt über die Havel und der andere über das Gewässer Hellers Loch, mit jeweils nach außen geneigten Bögen sowie einem einseitig aufgehängten Deck, das sich zur Bogenmitte hin aufweitet und einen Verweilbereich mit Bänken schafft. Die einseitige Seilaufhängung ermöglicht ungehinderte Blicke über die Gewässer und Baumkronen in die Umgebung. Durch die neue Brücke ist eine dauerhafte Verbindung zwischen der Kulisse Schwedendamm und dem Weinberg geschaffen worden. Sie ist der wichtigste Baustein für die touristische Entwicklung der Stadt Rathenow und des Optikparks. Construction of the Weinberg-Bridge in Rathenow for the Federal Garden Show 2015 in Germany. In Rathenow, a new 350 m long bicycling and footbridge spans the river Havel. The ogee Weinberg-Bridge was the main highlight of the Federal Garden Show 2015 in the Havelland. The horticultural show was located in the cities of Brandenburg/Havel, Premnitz, Rathenow and Rhinow/Stölln of the region of Brandenburg as well as in the city of Havelberg in Saxony-Anhalt. Over the two waters (Havel and Hellers Loch), the construction consists of two arch bridges with slanted archs, an unilaterally jointed bridge deck, which enlarges until the middle of the arch and offers benches for a stay on the bridge. The unilateral connection of the ropes enables unimpeded views over the waters and the trees in the surrounding area of the bridge. The permanent connection between the scenery of the Schwedendamm and the Weinberg is the most important part of the touristic development process of the city and the Optikpark. [ABSTRACT FROM AUTHOR]

Hochfeste Rohre und eckige Stahlbauhohlprofile für Krane sowie für den Maschinenbau werden eingesetzt, um bei zunehmender Auslastung den stetig wachsenden Anforderungen an die Konstruktion gerecht zu werden. In vielen Anwendungen besteht die Notwendigkeit, Konstruktionsmassen zu begrenzen. Damit werden entweder regulatorische Vorgaben, wie beispielsweise Achslastbeschränkungen bei Mobilkranen, oder andere anwendungsspezifische Erfordernisse erfüllt, wie die Steigerung der Hakenlast bei Gittermastkranen. Zudem bietet sich die Möglichkeit, Wanddicken zu reduzieren und damit den Verarbeitungsaufwand beim Schweißen zu reduzieren. Für Bemessung und Ausführung sind neben der Streckgrenze und den statischen Eigenschaften meist die Duktilität, die Kerbschlagzähigkeit sowie eine möglichst einfache Verarbeitung durch gleichmäßige Eigenschaften der eingesetzten Werkstoffe von zentralem Interesse. Dieser Beitrag bietet einen Überblick über Anforderungen, Herstellung und Eigenschaften hochfester nahtloser Rohre und Stahlbauhohlprofile. High strength seamless tubes and steel hollow sections for cranes and machine building applications - production and properties. High strength tubes and steel hollow sections for cranes and machine building applications are used with increasing utilization of the designs to cover continuously growing requirements. For many applications limiting construction weight is a necessity. Either regulatory inputs, like axle load limitation of mobile cranes, or other application-specific requirements such as load capacity of crawler cranes are covered. Additionally high strength steels allow wall thickness reductions and thereby give opportunity to reduce the effort of welding. For design and execution beside yield strength and static properties mostly ductility, impact properties and preferable easy processing through uniform properties of the used steel grade are key interests. This article will provide an overview of requirements, manufacturing and properties of high strength seamless tubes and steel hollow sections. [ABSTRACT FROM AUTHOR]

Steel as reinforcing material has dominated the civil engineering for a long time. However, some disadvantages occur by its insufficient corrosion resistance and the associated need for an adequate concrete cover. Those can be avoided using textile high performance materials, where carbon shows a high potential being promoted as concrete reinforcement material of the future. The development of carbon fibers opens a new field producing reinforced fiber composites. The outstanding properties and the resulting huge light weight construction potential as well as its defined tunable mechanical, thermal and electrical properties, carbon fibers find their way into a lot of industrial branches, namely like automotive- and mechanical engineering, aerospace engineering, energy production (wind energy) and building industry, especially textile reinforced concrete. The material for carbon fibers mainly bases on polyacrylonitrile made of mineral oil, which already in form of fibers passes through several thermal treatments to form and to design the properties of the carbon fibers. [ABSTRACT FROM AUTHOR]

Die Bauausführung für den Ersatzneubau der Schnettkerbrücke begann mit der Zuschlagserteilung an das Unternehmen Schachtbau Nordhausen GmbH im September 2005. Schnell zeigte sich, dass die Realisierung des Bauwerksentwurfs für die technisch und optisch anspruchsvolle Brücke in dieser exponierten Lage für alle Beteiligten eine große Herausforderung war. Die Herstellung erfolgte unter schwierigen Randbedingungen. So musste der Bauablauf unter weitestgehender Aufrechterhaltung des Straßen- und Bahnverkehrs erfolgen. Die Gründungssituation erwies sich als außerordentlich schwierig. Neben dem Neubau musste auch noch die alte Brücke mit einem aufwendigen Verfahren abgebrochen werden. Zusätzlich waren die Interessen der Bewohner des Stadtteils Schönau zu berücksichtigen, da sie während der Bauzeit vom Baustellenverkehr besonders betroffen waren. Der folgende Aufsatz beschreibt die technischen Lösungen zur Umsetzung der komplexen Bauaufgabe. Eine generelle Bauwerksbeschreibung erfolgte bereits einem ersten Teil über den Ersatzneubau der Schnettkerbrücke [1]. Replacement of the Bridge Schnettkerbrücke in Dortmund: Building of the bridge (part 2). The replacement of the Bridge Schnettkerbrücke started with the assignment of the construction company Schachtbau Nordhausen GmbH in September 2005. It was quickly to realize, that the building of this technical and optical ambitious bridge was a great challenge for all participants. The erection had to take place under difficult conditions. The disturbance of road and railroad traffic must be reduced to a minimum. The building of the foundations was very difficult. Besides of the building of the new bridge the old bridge must be deconstructed. The interests of the inhabitants of the urban district Schönau had to be respected, because they were disturbed by the site traffic during the whole construction period. The following paper describes the technical solutions to execute the complex construction process. For a general description of the bridge see [1]. [ABSTRACT FROM AUTHOR]

Im Zuge des Ausbaus der Autobahn A 40 wurde ein Ersatzneubau für die Schnettkerbrücke in Dortmund erforderlich. Neben den technischen Schwierigkeiten, die sich aus dem Bauen unter Aufrechthaltung des Verkehrs ergeben, war die Bauaufgabe auch durch besondere Anforderungen an die Gestaltung der neuen Brücke geprägt. Die außergewöhnliche Lösung ist eine technisch und optisch anspruchsvolle Brücke, bei der verschiedene Tragwirkungen miteinander kombiniert werden. Die Ausführung erfolgt als robuste Stahlverbundbrücke mit einer maximalen Stützweite von 132 m. Replacement of the Schnettker Bridge in Dortmund: Design of the bridge (part 1). In course of the expansion of the autobahn A 40 the bridge Schnettkerbrücke had to be replaced. Beside of technical difficulties, resulting from the request to build the new bridge while maintaining the traffic, there have been a lot of architectural requirements to the new bridge. The extraordinary solution is a technical and optical ambitious bridge, which combines different types of load carrying actions. The maximal span of the robust composite bridge is 132 m. [ABSTRACT FROM AUTHOR]

Der Bereich der Gewebe und Zellen ist geprägt durch ein Zusammenspiel des europäischen und deutschen Rechts. Die praktische Umsetzung der rechtlichen Vorschriften kann Schwierigkeiten bereiten. Auftragstätigkeiten im Zusammenhang mit der Entnahme von Gewebe und den Laboruntersuchungen zur Herstellung von Gewebezubereitungen oder Arzneimitteln für neuartige Therapien dürfen nur auf der Grundlage eines Vertrags durchgeführt werden. Derartige Verträge sollten nicht nur die Abgrenzung der Verantwortlichkeiten berücksichtigen, sondern auch den Besonderheiten im Bereich der Gewebe Rechnung tragen. Die eigenen Verträge sollten auf ihre Vollständigkeit und Aktualität geprüft und überarbeitet werden. Die zuständige Behörde ist befugt, Einsicht in die Verträge zur verlangen. Der Beitrag hat ausgewählte Fragen zum Gegenstand, die sich aus der Beratungstätigkeit der Autorin ergeben haben. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Since 1999, the composite material textile reinforced concrete (TRC) has been largely studied and developed at the universities of Dresden and Aachen in two DFG-Collaborative Research Centres. Until today, Germany is the world leader in this field. Numerous realized practical applications demonstrate the versatility and performance of the material. Nevertheless, the realization of TRC-projects is often difficult. Approvals in individual cases were necessary, since there were no national technical approvals until today. Getting a first building approval was a major step to overcome this obstacle. In the context of this approval, the present paper gives a brief introduction to the topic textile reinforced concrete. [ABSTRACT FROM AUTHOR]

The nitrous oxide production unit of the German Armed Forces was a worldwide unique facility which was only employed in the former main medical depot at Euskirchen (nitrous oxide: medical gas which is now obsolete). The last unit was phased out in 2002 and brought to the main medical depot at Blankenburg. Unfortunately the unit is now no longer in the depot and seems to have disappeared. This article describes the nitrous oxide production process and the use of the production unit which was designed by the Socsil company of Switzerland. [ABSTRACT FROM AUTHOR]

Spray forming produces cast microstructures with comparatively low macro- and micro-structural chemical segregation and is thus well-suited for the manufacture of complex chemistry, multi-component alloys that otherwise show strong elemental segregation. Although spray formed Ni superalloys have shown properties equivalent or superior to their conventionally cast/wrought counterparts, they have not been adopted commercially because of the difficulties in ensuring a high process yield and the complexity and associated cost of large-scale Ni superalloy melting. In this paper, we describe a hybrid arc spray forming (HASF) process in which costly, large-scale alloy melting as pre-cursor to spray forming is avoided by the use of a consumable wire feedstock. To achieve thermal conditions of melt spray forming - essential to produce a refined, polygonal grain structure - a customised secondary atomisation system has been developed. Fe-0.8 wt%C and Ni superalloy IN617 microstructures and preliminary mechanical properties suggested that hybrid arc spray forming may offer an attractive combination of convenience, low cost and mechanical performance. [ABSTRACT FROM AUTHOR]