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While this method can create new tunnels, I see it’s first best use at enlarging existing tunnels by setting the “concrete” type stuff surrounding an existing t
by sroussey 4y ago
While this method can create new tunnels, I see it’s first best use at enlarging existing tunnels by setting the “concrete” type stuff surrounding an existing tunnel but at a larger diameter (well, also need not be round!). Then demolition of the existing tunnel walls and some cave in of other materials and you have a new larger tunnel after cleanup.
- dylan604 4y agoYou'd still lose use of the existing tunnel. Why not build a new second tunnel?
- komadori 4y agoIf you want to increase the loading gauge of a railway, it may be expensive/difficult to reroute the track to go through a different tunnel. Also, making the track less straight may impair the maximum speed of the line.