10.07.2018 - Blasting work right on track

10.07.2018 - Blasting work right on track -

More than 4,900 of a total of 5,860 metres of the new Albula Tunnel have now been cleared. This is around 83 per cent of the entire length. The breakthrough is expected to take place in autumn 2018.

Among other things, suitable excavated rock from the tunnel will be re-used as top-quality fill material for RhB's new double-track section Bever - Samedan.

The planners and building contractors involved are already busy with the preparations for the next stage of construction, "lagging/interiorwork", right up until the tunnel is opened in 2021. Measurements have shown that a maximum deviation of 50 millimetres is to be expected for the imminent tunnel breakthrough. For this purpose, a network of five measurement bench marks was created at each of the two portals and determined highly precisely with a satellite-aided navigation system (GPS). Inside the tunnel, laser tachymeters are used to measure angles and distances and thus provide the basis for the surveyors to calculate the coordinates.