How China Is Building a High-Speed Railway Tunnel 78 Metres Under the Sea

🌊 How do you build a high-speed railway deep beneath the sea? 🚄 In this video, we follow the full construction process of China's Jintang Undersea Tunnel, part of the Ningbo–Zhoushan high-speed railway in Zhejiang Province. The tunnel is planned at 16.18 km, with an 11.21 km shield-bored section reaching about 78 metres beneath the water surface during construction. 🏗️ 🔍 What you will learn: ✅ Route selection and seabed surveys 🗺️ ✅ How water pressure is calculated 💧 ✅ Tunnel boring machine (TBM) parts and how they work ⚙️ ✅ Slurry shield excavation and muck removal 🚧 ✅ Concrete lining, waterproof gaskets and grouting 🧱 ✅ Leak control, cutter changes and ground monitoring 🔧 ✅ Track, power, signalling and safety systems 🚉 ✅ Testing and commissioning before passengers ride 🛤️ 📅 Project status: The tunnel is still under construction. Reports say the railway is planned to open by 2028. Details may change as work continues. 👍 If you enjoyed this, LIKE the video, SUBSCRIBE to the channel and press the 🔔 bell icon so you never miss the next engineering documentary! 💬 Which mega project should we cover next? Tell us in the comments! ⚠️ DISCLAIMER: This video is for educational and informational purposes only. It explains general underwater shield-tunnelling methods alongside publicly reported facts about the Jintang Undersea Tunnel. Figures such as length, depth and schedule come from public reports and may change. Construction details are simplified, and some stages describe the standard engineering work needed to complete a railway tunnel, not confirmed events on this specific project. This channel is not affiliated with China Railway or any company or government body mentioned. 🤖 AI CONTENT DISCLOSURE This content includes AI-assisted visuals for educational and informational purposes. While accuracy is reviewed, some scenes may be simplified or dramatized for visual explanation 🎬 CLIPS AND COPYRIGHT All clips and visuals in this video were created by the channel owner. Please do not re-upload or reuse them without permission. #JintangTunnel #UnderseaTunnel #UnderwaterTunnel #ChinaEngineering #ChinaInfrastructure #NingboZhoushan #HighSpeedRail #HighSpeedRailway #UnderwaterRailway #TunnelBoringMachine #TBM