3 ms·
This is also a technique that was used more than 100 years ago for the line 4 of the Paris métro: https://www.ratp.fr/en/discover/out-and-about/culture/history-
by padenot 2y ago
This is also a technique that was used more than 100 years ago for the line 4 of the Paris métro: https://www.ratp.fr/en/discover/out-and-about/culture/history-metro-line-4 https://www.ratp.fr/en/discover/out-and-about/culture/histor...
- llsf 2y agoFunny that they had to freeze the ground to dig it, as it is one of the hottest line in Paris (at least 20 years ago).
- s1artibartfast 2y agoMy understanding is that the freezing is normally about stopping water intrusion long enough to drill and place concrete