Report. Integral Bridges. Author Marianne Haditsch. Research Area Faculty of Civil Engineering Sciences. Supervisor Dipl.-Ing. Regina della Pietra

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1 Report Integral Bridges Author Marianne Haditsch Research Area Faculty of Civil Engineering Sciences Supervisor Dipl.-Ing. Regina della Pietra Chairmanship O. Univ.-Prof. Dr.-Ing. habil. Viet Tue Nguyen Institute of Structural Concrete University of Technology Graz, Austria

2 INTRODUCTION 1 INTRODUCTION In the context of the project "Rio scientists and young people take stock" I got the chance to spend two months at the Institute of Structural Concrete at the University of Technology in Graz and therefore gained some insights into different fields of building technology. Rio + 20 is an international organization based on the world summit on sustainable development in Rio de Janeiro, consisting of organizations and members of government from different nations. Their aim is to support social justice and environmental protection but also to reduce poverty. They especially deal with the topics of sustainability, resources and climate change - topics which I am very taken with. Fortunately, people talk about sustainability more and more, but only a few of them recognize the gravity of the situation. To live more sustainably means to consume more sustainably. We have to use the resources of our planet and consider the needs of future generations at the same time, they shouldn't have to worry about how to handle their lives. We have to deal with our commodities more economically, because at the moment we would need three earths if the entire humanity lived like the Europeans do. Many of us struggle with this topic but only a few really change their way of life. During my time at the institute I learned a lot about infrastructure, bridges and building itself. I worked intensively on the construction of bridges and learned that it is also possible to work sustainably and economically in this field. Currently, integral bridges, i.e. jointless and bearingless bridges, become more and more important. In contrast to conventional bridges, the costs construction and maintenance are reduced with the help of that technology. Beside these and a lot of other advantages, the "demanded durability" of integral bridges is one of the main arguments in favor of this technology. Through the elimination of grooves and brackets it is possible to work more sustainably and cost-effectively. Traffic jams and, consequently, environmental pollution are reduced. Even in antiquity integral bridges were created, based on the model of Roman stone arch bridges made entirely of natural stone. The first concrete bridges 1

3 INTRODUCTION were built about two thousand years ago. At that time the Romans used a coarse mortar, which bears a great resemblance to modern building materials. In the late 19th century, people reverted to the jointless building technology, but it has only been in use for the last few years again. Figure 1-1 Pont du Gard, 1. Century AD Mainly in the USA integral bridges are already "standard". Currently, about bridges without any grooves or brackets are in use, including 9000 integral and 4000 semi-integral bridges. The first integral bridge in the USA, the "Teens Run Bridge", was built in 1938 near Ohio. The first integral frames in Japan and South Korea were built in 1996 and 2002, respectively. In Europe the percentage of integral frames is increasing as well. In Britain, for example, more than sixty per cent of the structures in 2004 were built in an integral style, 1650 integral bridges in Switzerland alone. Although the proportion of integral structures is increasing continuously, conventional bridges still predominate, as comprehensive guidelines for integral structures are not yet available. because in the integral technique guidelines are not completely given. The intention of sustainable construction is the minimization of the consumption of energy and resources. It takes all life cycle phases of a building/structure into account. (Dietrich Schwarz, Zurich) The integral building technology permits a configuration according to these principles. Conventional frames create higher life cycle costs and require frequent maintenance. According to that, integral bridges become increasingly significant. In this paper I will give a few examples for integral bridges in Switzerland and Germany. I will also describe them in detail and define the international status of integral frames. 2

4 continental frames 2 CONTINENTAL FRAMES The highest share of international integral frames is to be found in Europe, but an exact number cannot be given. We especially encounter bridges without any bearings and joints in Britain, Scandinavia and Sweden, with most of these structures about 90% of all European constructions built in Germany. In the following section I will give three examples each of integral bridges in Switzerland and Germany. 3

5 continental frames 2.1 IN SWITZERLAND SUNNIBERGBRÜCKE Structural system Road bridge Overstretched girder bridge/ five-span prestressed/ ground plan curvature Span [m] L i = 59.0 m m m m m; L max = m; L ges = m Width [m] Carriageway cross section B ges = 12,37 m Tee beam cross section with two edge girders h K 1.0 m Prestressed concrete Foundation Pile foundation at the supports/ Shaft foundation at the abutments Switzerland/ Klosters Year of construction 1998 In a wide curve the Sunnibergbrücke bridges the valley of Landquart, 62 metres above the ground. It was opened in 2005 and connects the villages of Bühl and Drostobel. Figure 2-1-1: Bridge 4

6 continental frames SALGINATOBELBRÜCKE Road bridge Structural system Arch bridge Span [m] L ges = m Width [m] B ges = 3.80 m Reinforced concrete Switzerland/ Schiers Year of construction 1930 Robert Maillart, one of the most popular engineers of the German-speaking region, built the Salginatobelbrücke in 1930, which probably is the most popular building of his entire work. In an elegant way it bridges the valley of Salgina and makes the surrounding area shine in all its glory. Figure 2-1-2: Bridge 5

7 continental frames SCHWANDBACHBRÜCKE Road bridge and pedestrian bridge Structural system Suspended deck arch bridge Span [m] L ges = m Width [m] B ges = 4.9 m Reinforced concrete Switzerland/ Hinterfultigen Year of construction 1933 The Schwandbachbrücke is located between Hinterfultingen and Schönentannen, crossing the Schwandbach river. Together with the Salginatobelbrücke and the Ziggenbachbrücke it ranks among the best constructions of the 20th century. Figure 2-1-3: Bridge 2.2 IN GERMANY 6

8 continental frames NESENBACHTALBRÜCKE Structual system Road bridge and pedestrian bridge Frame bridge/ 6- span- pre- stressed/ Ground plan curvature/ Restraint thrust bearing (100%) Span[m] L i = 8.25 m m m m m m; L max = m; L ges = m Width [m] Carriageway cross- section B ges = m Board cross- section on underlying space truss/ h K = 2.28 m Reinforced concrete/ Steel (framework and supports) Foundation Pile foundation at inner supports (ø= 0.90 m)/ Flachgründung im Widerlagerbereich Germany/ Stuttgart- Vaihingen Year of Construction 1999 The girder bridge with a length of nearly 151 meters connects Österfeld and Vaihingen by its curved construction. Additionally it gives an excellent protection against noise and a unique view of the Kaltental. Figure Bridge LA- FERTÉ- STEG 7

9 continental frames The pedestrian and cyclist s bridge, which was built 2001 in Stuttgart-Zuffenhausen, creates in consequence of its dynamic swinging form a harmonic but also noble atmosphere. With a Pedestrian bridge Structural system Girder bridge/ Multi- span/ Ground plan curvature/ Abutment tension (100%) Span [m] L max = 28.5 m; L ges = m Width [m] b ges = 3.50 m Carriageway cross section Tee beam cross section/ h K = 0.75 m Reinforced concrete/ Steel stanchion Foundation Pile foundation at the thrust bearing Germany Stuttgart- Zuffenhausen Year of concrete 2001 length of 119m and a radius of 53.70m, a residential area, a fairground and an indoor pool get connected by a circle arc. Figure 2-2-2: Bridge BIDGE ACROSS THE GAHLENSCHE STREET BOCHUM Pedestrian bridge 8

10 International frames Structural system Suspension bridge/ One rope plane Span [m] L 70.0 m (Pylon distance) L ges = m Width[m] b ges = 3.0 m Carriageway cross section Board cross section/ Composite panel H K 1.15 m Reinforced concrete of the board/ Steel (Pylon, Rope, Cross member) Foundation Pile foundation at the thrust bearings and pylons/ Ø= 1.20 m, l pf = 25.0 m Germany/ Bochum Year of construction 2003 This pedestrian bridge was built in 2003 and is one of the first double-curved, one-sided supported suspension bridges in the world. An S-shaped curve connects two staggered sidewalks. Dipl.- Ing. Kurt Göppert developed this design in the course of a competition and implemented it in a reasonable way. Figure 2-2-3: Bridge 3 INTERNATIONAL FRAMES 9

11 International frames Especially in the USA the integral design is already standard. Currently, there are bearingless and jointless bridges, including 9000 integral and 4000 semi-integral bridges. However the number of integral constructions in different countries varies, as well as the guidelines, such as the maximum permitted spans and total lengths. In 59% of all federal states, for example, there are fifty integral frames, whereas 15% of the federal states account for 1000 integral bridges. The first integral bridge of the USA, the Teens Run Bridge near Ohio, was created in 1938, whereas the first integral frames in Japan and South Korea were not built before 1996 and 2002, respectively. 3.1 USA SEMI-INTEGRAL BRIDGE ON ROUTE 18 OVER BLUE SPRING RUN 10

12 International frames Road bridge Structural system Girder bridge/one- field truss/crooked α=45 Span [m] L ges = 33m Width [m] b ges = 13m Reinforced concrete Foundation Pile foundation USA Year of construction 2005 Figure 3-1-1: Bridge 11

13 Model and group photos 4 MODEL AND GROUP PHOTOS Model Integral Bridge Annual outing on August 24,