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Benning H.,Bundesministerium fur Verkehr | Goj K.,Oberste Baubehorde im Bayer | Marzahn G.,Landesbetrieb Strassenbau Nordrhein Westfalen | Mertzsch O.,Landesamt fur Strassenbau und Verkehr Mecklenburg Vorpommern
Bauingenieur | Year: 2012

While analyzing traffic volume on current German autobahns, it became obvious that the planned capacity of most highway bridges has been almost exceeded by daily traffic volume, Including increasingly heavy trucks with rising numbers of axles and load size. In fact, to ensure future long-term serviceability of the German autobahn system, there is no way around refurbishing most of these bridges, by combining ordinary maintenance work with strengthening measures, and replacing numerous others as well. A realistic assessment of existing highway bridges that comprises bearing capacity, serviceability, and fatigue resistance in order to evaluate their structural health is a widely accepted prerequisite for a long-lasting refurbishment strategy. The provisions reported here for evaluating necessary upgrades of older bridges provide an appropriate tool for setting uniform standards in assessing existing highway bridges to ensure comparability of results and the conclusions drawn from them.

Hegger J.,RWTH Aachen | Marzahn G.,Bundesministerium fur Verkehr | Teworte F.,HP Ingenieure GmbH and Co. KG | Herbrand M.,RWTH Aachen
Beton- und Stahlbetonbau | Year: 2015

The structural assessment of existing road bridges that has been recently performed on the basis of the equally named provisions, issued in 2011 by the Federal Ministry of Transport and Urban Affairs, have revealed significant deficits in shear and torsion as well as fatigue resistance especially in prestressed concrete bridges. In a research project, funded by the Federal Highway Research Institute of Germany, design methods have been developed that were incorporated into the first addendum of the Structural Assessment Provisions. This paper describes the respective design methods for shear under static and cyclic loading without shear reinforcement. The procedures take into account current research results as well as the design codes for concrete bridges and are based on a verification of the principal tensile stresses. The use of the procedure and the main results are shown exemplarily by a design example of a typical box girder bridge of the German road network. © Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG.

The traffic forecast assumes a sharp increase in goods transport by road. In the future, this will result in an even higher traffic load and thus to an even higher degree of wear of the bridges. Many older bridges can no longer fully meet the continually increasing requirements. These structures, including many large valley and river bridges, are affected more and more by wear and tear and damages. They are located almost exclusively in the old federal states. The question arises as to how these bridges can be used or even strengthened in the future. With the strategy for post-test calculations and strengthening of the bridge stock developed by the Federal Ministry of Transport, Building and Urban Development a nationally uniform approach was elaborated together with the Federal Highway Institute and the road construction administration of the federal states. This concept aims at examining for everyone of the individual bridges concerned whether it still meets the requirements of heavy-goods transport today and in the future. The so-called post-test calculation guideline specially developed for this purpose forms the core of this task. What needs to be done is to improve the structural condition of the road bridges as well as to eliminate deficits of the load-bearing capacity. The objective of all efforts has to be the prevention of extensive traffic restrictions up to the closure of a bridge. Copyright © 2013 Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.

With the "Flutmulde Rees" flood retention basin between Rhine kilometres 833.5 and 839.0 and an amount of more than EUR 56 million invested, the Duisburg-Rhine Waterways and Shipping Agency is realising one of the biggest hydraulic engineering projects in the history of the WSV. Designed as a side channel, the project has been under construction in a 5-year building period on the left side of the Rhine across the city of Rees since September 2009. The flood basin is part of an overall project to deepen the fairway of the Lower Rhine between the Port of Duisburg and the ports of Antwerp, Rotterdam and Amsterdam from 2.50 to 2.80 metres below the reference water level. The local, over-proportional erosion tendencies are being minimised and the water bed globally stabilised by partially draining off the floodwater through the flood basin. Thanks to the installation of elements to secure the ecology and its effect of neutralising floodwater, the "Flutmulde Rees" is also setting trends from a water management perspective.

Friebel W.-D.,Bundesministerium fur Verkehr | Blosfeld J.,Bundesanstalt fur Strassenwesen BASt | Kaundinya I.,Bundesanstalt fur Strassenwesen BASt
Bautechnik | Year: 2010

In the recent past it was shown that road tunnels can be damaged severely by large fires. For that reason several international research projects were carried out for further development of structural fire protection of road tunnels. Based on international research projects three national research projects were initiated by the Federal Ministry of Transport, Building and Urban Development (BMVBS) and the Federal Highway Research Institute (BASt). In the course of these projects existing temperature-time-progressions (so called "fire curves") for road tunnels, fire tests in tunnels and real fires in road tunnels were analyzed with regard to a possible application for the design of structural fire protection of road tunnels. Furthermore the temperature penetration in the tunnel lining and the load bearing capacity of usual tunnel sections were numerically examined under fire influence. Finally the influence of fiber-modified concrete on the effect of explosive spalling was investigated by means of large scale fire tests on specimens made of concrete for tunnel lining. In the following procedures and results of the national research projects are described. © Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin.

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