There are tens of thousands railway bridges across Europe. Furthermore, there are road bridges in order to cross the tracks. Some of them are rather boring as they are poured in concrete. The railway construction article for this club magazine focuses on a bridge pillar which is skilfully built from stone.
Trains prefer to travel in the plane. As you know, in the case of the wheel track system the steel wheel rubs against the steel track. Therefore, it‘s adhesion is less than that of the rubber tires of a bicycles on street tarmac. The low adhesion has a big advantage: A train consumes considerably less electrical energy or diesel than a road vehicle with the same weight and load. Thanks to the low adhesion, a locomotive that weighs just 80 tons is capable of pulling a train weighing 1000 tons without getting out of breath. Only the starting requires great sensitivity. In the case of a heavy freight train, wagon after wagon will start individually, until the entire cartload is rolling.
The low adhesion is disadvantageous when the train needs to travel over hills and valleys. The railway doesn‘t like slopes – the word comprises up and down gradients – above all the great ones. Already slopes that are barely visible are problematic for the locomotives. The early mountain railway lines in the Alpine area, for example, reach slopes of 25 per thousand. That means that the route section rises or drops by 25 metres on a length of 1,000 metres. You can master that easily on your bicycle. Even for modern electric high-performance locomotives 25 per thousand stand for incredible strain.
Therefore, the railway route builders paid attention to plan the railway lines as level as possible right from the start. Of course, this is not always possible, since trains have to cross mountains and valleys. So the railway company created engineering structures, those used to be almost only bridges in the early days, and then also tunnels.
Bridge construction was already known in ancient times. Finally, the people wanted to cross the rivers and creeks with dry feet already back then. So the master builders started working. Some ancient Bridges survived until today. In the course of the centuries, one or another bridge over a deep canyon was built. Most of the bridges continued to serve for crossing waters. That changed only with the invention of the railway. From this time on, everywhere across the country bridges of different heights and lengths were built. Some of them moved up to attractions, as for example the Bietigheim Viaduct.
In the early days, almost every bridge war made from stone. Later, the engineers developed artistic structures from iron and steel. Concrete was added already at the turn of the 20th century. Along the Mittenwald railway from Mittenwald to Innsbruck, which was inaugurated on 1912, almost all bridges are made from concrete. So, this material has been longer been in place than some may believe.
At the Thomas Mann Gymnasium in Stutensee classic bridges, or more precisely bridge pillars, were made from stone. Julia explains the construction using the example of a pillar. Of course, she didn‘t build it stone by stone. Instead, she used Styrodur. It is a little lighter than stone, it can be processed more easily and is capable of safely and reliably bearing a bridge across railway tracks. It is however considered to use plaster pillars for a bridge that crosses your railway line. They become stone pillars in the same ways as Julia shows with Styrodur.
She used a sharp tinker knife and a screwdriver for carving the structures of the stones into the material. When using Styrodur, the tinker knife doesn‘t need to be as sharp as for plaster. And this is the difference. Afterwards, the pillar receives a coat of grey paint. You can choose which grey or dun colour you want to used. In nature, there are numerous stones in different colours. Finally, Julia applied heavily diluted black colour which she wiped away after a short time of drying. In this way, the black colour stays in the joints and other contours. The colour had to dry, afterwards the pillar was ready.
Then, Niklas installed it into a module. There used to be a bridge over a depression where a railway line runs parallel to a road. The central pillar is still standing. Also the bridge bearing on one side is still recognizable. On the other side you can only forefeel where the bridge used to begin. Of course, there are also bridges that were eventually no longer required. It was often removed because it urgently needed to be restored. Then, the question was whether it is worthwhile repairing it. If it was found that the bridge was no longer needed, they stopped the works. In this case, a pillar was left behind in the landscape.
some Styrodur, a sharp tinker knife, a screwdriver, grey and black colour. The set-square is very helpful when measuring. You find the Styrodur in packaging waste. If you build the pillar from plaster, you also need a mould. You can buy that at your specialized Märklin dealer. In this case, the stones are already preformed so that you only have to emphasize them with the tinker knife.