How Hong Kong Built an Underwater Train Tunnel that Defies the Ocean

Hong Kong East Rail Line construction: how engineers built a train tunnel under a live shipping lane, 30 metres below Victoria Harbour, for HK$90 billion. Right now a cargo ship crosses Victoria Harbour above a speeding East Rail train. Both in the same harbour. Simultaneously. That tunnel — 11 concrete boxes, each 23,000 tonnes, built at Shek O Quarry, floated out, and sunk one by one to the harbour floor at night — took 10 months, a rebuilt gravel bed after a cargo anchor dragged through it, and a Marine Police lane closure for every single element. This documentary covers the full engineering and construction process: harbour immersion, 7 TBMs, 700 defective rebar bars found buried in load-bearing walls, the Island Line underpinned live 22mm past its 20mm limit, and the Category 10 simulation that puts joint 3 at 96% of design capacity. What's in this video: How engineers built 11 tunnel elements on land, floated them out, and sunk them 30 metres to the harbour floor How a 23,000-tonne element was held at 15 metres depth for 4 days while engineers rebuilt the gravel bed below it How a 23,000-tonne element was held at 15 metres depth for 4 days while engineers rebuilt the gravel bed below it How 7 TBMs were built through marine clay, granite, and 400 uncharted building piles simultaneously How 700 defective bars were found buried in load-bearing station walls — and how a steel frame was built to bypass them Subscribe to NEXTGEN MANUFACTURING to understand the incredible machines, blueprints, and megaprojects that built our world. #EastRailLine #Megaprojects #HowItsMade #HongKong #FactoryTour #Engineering #UnderwaterTunnel #Construction #InsideTheFactory #StormSurge #Tunnel #FullProcess #Aviation #Trending ⚠️ IMPORTANT: ABOUT THIS VIDEO ------------------------------------------------------------------- This is an educational documentary analyzing the engineering and construction of public infrastructure, based entirely on open-source information. All visuals