Tunnel hole-through, also called breakthrough, is the time, during the construction of a tunnel built from both ends, when the ends meet,[1] and the accuracy of the survey work becomes evident. Many tunnels report breakthroughs with an error of only a few inches, for example:

Dismantling the tunnel boring machine 10 days after the hole-through on the Gotthard Base Tunnel in Switzerland.

See also

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References

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  1. ^ "Governor Rockefeller and Mayor Lindsay Attend 'Holing Through' of 63d St. Tunnel". The New York Times. October 11, 1972. Retrieved January 24, 2017.
  2. ^ Lotschberg
  3. ^ "ASCE Metropolitan Section - Holland Tunnel". www.ascemetsection.org. Retrieved 2020-11-21.
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