I'm not an engineer so I might be missing something, but according to Wikipedia[0]: > The precast concrete tunnel sections will have a rectangular cross-sectio

I'm not an engineer so I might be missing something, but according to Wikipedia[0]: > The precast concrete tunnel sections will have a rectangular cross-section that is about 40 metres (130 ft) wide and 10 metres (33 ft) high and (also mentioned in the video): > The tunnel will consist of 79 standard elements with a length of 217 metres If it's a perfect cuboid, this should result in a buoyancy corresponding to ~87,000 tonnes. According to the video, each segment weighs (over) 73,000 tonnes, though this presumably doesn't include other stuff that will be added into the tunnel like road surface material, rail tracks etc. [0] https://en.wikipedia.org/wiki/Fehmarn_Belt_Fixed_Link#Tunnel_characteristics https://en.wikipedia.org/wiki/Fehmarn_Belt_Fixed_Link#Tunnel...