Tunnel hole-through

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
Dismantling the tunnel boring machine 10 days after the hole-through on the Gotthard Base Tunnel in Switzerland.

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:

See also[edit]

References[edit]

  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

External links[edit]