in the face of crumbling concrete, of all places, bridges and borders, it is almost a miracle that historically valuable steel bridges under the load of modern traffic collapse. But the railway uses will remain unchanged in 1859, between Waldshut in Baden and the Swiss town of Koblenz-built bridge over the Rhine and other old iron constructions.

you must, However, engage with the Parties of special circumstances, because of the bridges from previous eras work differently than today’s. It takes a lot of idealism. Because “the engineers have no incentives to maintain buildings; also, the construction industry has no interest in it,” says Eugen Brühwiler, dealt Professor at the Technical University in Lausanne. Here, the taxpayer will be ignored and the monument care to be ridiculed. Only individual citizens hold against it. Still a countless number of riveted steel bridges will be replaced by new buildings, because they are valid, without this being scientifically proven as too little to be viable, and susceptible to fatigue fractures. In the process, have been expanded since about 1990-thanks to the vivid research, knowledge about the structural behaviour of such bridges much so that today a realistic Review of these structures is possible, explains Brühwiler.

the security for important parts of the 1897-built bridge over the Rhine at Eglisau in Switzerland, the computer was not met. Therefore, in 2012, was launched a year-long measurement program, to be able to seasonal influences. This data is supported, the condition of the bridge as a safe judge of that. On structural interventions has been omitted. Despite the effort, this investigation was compared to that of construction much cheaper. And the 63-Meter height over the river leading iron truss bridge will continue to remain a landmark of the Swiss railway.

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About 20 kilometers downstream, the above-mentioned oldest operating iron railway bridge in Europe. Three fields with the typical Lattice truss made of welding iron, spanning the river. In 1999, the route was electrified. Since then, 80 passenger trains daily pass the 130-Meter-long structure. Thus, the was able to stay to the same Parts of the Deutsche Bahn and the Swiss Federal Railways belonging to the bridge in operation, only the beams under the tracks in 2015, renewed. The historical image is retained.

The interests of railway companies and monument protection can match. Time-consuming investigations, as well as targeted repairs were, in many cases, still much cheaper than a new building, says Brühwiler. Sometimes, existing structures could be reinforced with a sense bridges renewed to stay for more decades in operation. However, in order to understand the function of older structures in Detail, non-destructive testing, or test loads is important. The load carrying capacity of bridges can be a practical check. It had buttons holding on to the old structures, says the Professor.

the new methods for the Verification of existing structures are penetrated hardly in the engineering practice, because standards are lacking. However, the not or sense only according to apply to older structures work differently. In Switzerland In 2011 standards for the Review and maintenance of existing structures have been published. In Germany, you are missing until today; there are only guidelines, which are limited to the computation and tend to be “very conservative compared to the reality,” says Brühwiler. This often leads to exaggerated measures.