채널 터널 | 그 뒤에 숨겨진 놀라운 공학 기술
Sabin 토목공학 · 18:58
The Channel Tunnel was not a simple “dig a railway under the sea” job: the decisive problems were the piston-effect air resistance in a sealed bore, staying inside a thin, watertight chalk-marl layer without GPS, and...