Passenger service has begun in Seattle on the world’s only railway built on a floating bridge. Trains weighing about 272 tonnes cross Lake Washington on a structure that responds to wind, waves and changes in water level. For passengers, it is an ordinary trip, but for engineers it is a far more complex task: turning a moving bridge into a reliable railway.
The lake is about 60 metres deep and sits in a glacial basin with a soft bottom, so conventional supports are practically impossible here. Engineers had to solve three problems: weight, movement and electricity. They reinforced the structure, created flexible rail sections and protected the metal against corrosion.
It is now working infrastructure рассчитанная on tens of thousands of passengers every day. This technology is especially interesting for deep bodies of water: the bridge rests on pontoons and does not require supports reaching into the ground.
