It reminds me of the construction of the Chunnel that

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• the double-railway tunnel solved the problem of ventilation～ -妖妖靈- ♀ (0 bytes) () 02/18/2024 postreply 08:50:04

• Thanks. What do you mean by "the double-raillway..."? -唐宋韻- ♂ (0 bytes) () 02/18/2024 postreply 08:56:02

• At the beginning when they designed the Channel Tunnel. Now, -妖妖靈- ♀ (5785 bytes) () 02/18/2024 postreply 09:07:13

• As shown, Holland Tunnel is diff. It only has 2 tubes. -唐宋韻- ♂ (0 bytes) () 02/18/2024 postreply 09:11:13

• At the very beginning, it was very creative to have the idea -妖妖靈- ♀ (0 bytes) () 02/18/2024 postreply 09:16:35

• of a 2-rail design instead of a single-rail one. -妖妖靈- ♀ (0 bytes) () 02/18/2024 postreply 09:17:59

• Channel Tunnel, even for train, is too long to ignore ventin -唐宋韻- ♂ (0 bytes) () 02/18/2024 postreply 09:17:44