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I want to mention a recent extension to Berlin‘s subway system right in the middle of the city, in swampy ground and below a canal. They injected „freeze lances
by baumschubser 2y ago
I want to mention a recent extension to Berlin‘s subway system right in the middle of the city, in swampy ground and below a canal. They injected „freeze lances“ into the ground, turned 43,000 m^3 of mud into an ice block and then carved their way through it. Absolutely amazing engineering, I think planned and executed by a Swiss company.
- Haemm0r 2y agoGot a link for this? I am interested :-)
- getwiththeprog 2y agoI can find https://www.berlin.de/en/news/8097068-5559700-stabilization-work-u2-tunnel-alex-friday.en.html https://www.berlin.de/en/news/8097068-5559700-stabilization-... Which states that due to sandy soil concrete was injected with lances. It was done by a French company. Might be the same tunnel?
- pwarner 2y agoBig Dig also used ground freezing. https://babelniche.com/2024/01/17/innovations-of-the-big-dig-2-slurry-jacking-freezing/ https://babelniche.com/2024/01/17/innovations-of-the-big-dig... And the Erie Canal dig the sections through swampy ground in the winter. That was partially to avoid Malaria. Circa 1825
- padenot 2y agoThis 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