In our new section, the curve, there will be 2 railway tunnels and 1 gallery. Their construction will be discussed here.
First, there are quite a few conditions we have to take into account:
1. It is a modular layout
2. There is a functional overhead line, the pantograph always makes contact with the contact wire. Therefore, extra attention must be paid to the transitions between the modules. The contact wire here will consist of a brass wire. This makes it possible to have transition tubes at the ends of each module over the brass contact wire and so have a "continuous" contact wire.
3. The contact wire transition between the visible parts and the tunnel parts will have to be made in a different way as the contact wire in the visible parts is very thin. Here we are going to use springs to fix and tension the contact wire in the beginning of the tunnel. We have to make sure that the pantograph can easily make the transition and that everything is visually acceptable.
4. The inside of the gallery and the tunnels must be finished: rock faces, walls, support beams...
5. At the rear there are lockable openings to allow intervention in the event of derailment or technical failure. The edges of these openings must be hidden as well as possible. Also in terms of fastening these inspection hatches, they should stick out as little as possible at the back. Indeed, each module is packed in a box for transport to an exhibition. Therefore, we will try to keep the hatches in place by means of velcro straps.
6. Through the openings of the gallery, the inside of the tunnel is visible. Here again, the choice of the height at which the walls are placed will determine what the spectators get to see. The height of the contact wire is 16.5 cm above the track. The ceiling of the gallery is at 27.5 cm above the rail.
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