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The Art of Scaffolding
Built in 1901/1902, this 142 meter long railway bridge is today considered to be the emblem of the railway company. It crosses over the unspoilt Landwasser valley at a height of 65 meters. Around 9,000 cubic meters of calcareous dolomite stone from a nearby quarry were used to build this protected monument, an elegant bridge with five piers and six semicircular arches each with a span of 20 meters. The construction method using local stone produced an impressively harmonious appearance that blends into the mountainous landscape: one more reason why UNESCO awarded World Heritage status to this structure last summer, as part of the overall work of art "Rhaetian Railway in the Albula / Bernina Landscapes", which is only the third railway worldwide to be so honoured.
As the biggest and most spectacular structure on the 63 km long Albula route, which is also used by the world-famous Bernina Express and Glacier Express scenic trains, the Landwasserviadukt is also regarded as a civil engineering masterpiece. The three main piers of the viaduct, which is not free-standing but merges into a tunnel at both ends, were built up without scaffolding. The elegantly curving bridge is also the most popular photo motif along this route. At the present time, however, when the passengers take up their places at the right-hand windows and push their windows down, camera at the ready for the moment when the train is nicely curving round and high over the valley, they are in for a surprise: instead of the curved arches of the railway bridge they will see a work of art – wrapped up Christo-style. This is because the bridge is being refurbished – for the first time since it was built over 100 years ago, and without changing the outward appearance of this UNESCO World Heritage structure. For the tracks, a new gravel bed is being laid, and the stonework is being restored. Train services are continuing to run using temporary steel bridges. While scaffolding was not used during the original construction work, the Swiss company Lawil Gerüst AG erected, in around seven weeks starting in March, work scaffolding with a covered surface area of around 6,000 square meters, using Layher Allround equipment. This was done under tough conditions for the team of erectors, up to 14 strong, from both the logistical and engineering viewpoints.
Using a specially built roadway, the 750 tons of Allround equipment (which the company could request from Layher "just in time", thanks to standardized production plus a policy of keeping ample stocks) were transported to the foot of the viaduct by a twin-axle truck. The problem with the upward-tapering geometry of the piers was solved during scaffolding construction by using projecting structures. These brackets were mounted on the structure at ten meter intervals using a special holder. To build scaffolding around the sweeping arches of the viaduct around 50 meters up, an Allround lattice beam spanning 12.85 meters was installed between the pier scaffolding. The exact positioning of the scaffolding presented the biggest challenge here: the scaffolding erectors were able to rely on the accurate fit of the Allround system, as Josef Tresch, managing director of Lawil Gerüst AG, reported. The visual high point is however the scaffolding cladding: for the front face, a protective net in bright red was selected – this has long been the colour of RhB's trains. This has made a virtue of necessity, since after all one million passengers are expected to cross the viaduct by the autumn: while visitors are usually disappointed whenever famous landmarks are obscured by scaffolding, in this case there is astonishment at the red Christo-style wrapping, which used around 350 rolls of protective netting each 50 meters long. And which made the scaffolding into a work of art.
In charge of PR enquiries or contacts with the press:
Ms. Andrea Beisswenger
E-Mail Andrea.Beisswenger@layher.com
Telephone +49 71 35 / 70-0
Fax +49 71 35 / 7070-422
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