Vasco da Gama Bridge is a cable-stayed bridge flanked by viaducts and roads that spans over the Tagus River near Lisbon, capital of Portugal. It is the longest bridge in Europe with a total length of 17.2 km or 10.7 miles.
Bridge sections
Bridge sections
- North access roads
- North viaduct - 488 m (1,601 ft)
- Expo viaduct - 672 m (2,205 ft); 12 sections
- Main bridge - main span: 420 m (1,378 ft); side spans: 203 m (666 ft) each (total length: 829 m/2,720 ft); cement pillars: 150 m (492 ft)-high; free height for navigation in high tides: 45 m (148 ft);
- Central viaduct - 6.351 m (20.84 ft); 80 pre-fabricated sections 78 m (256 ft)-long; 81 pillars up to 95 m (312 ft)-deep; height from 14 m (46 ft) to 30 m (98 ft)
- South viaduct - 3.825 m (12.55 ft); 45 m (148 ft) sections; 84 sections; 85 pillars
- South access roads - 3.895 m (12.78 ft); includes the toll plaza (18 gates) and two service areas
Construction and cost
The project was split in four parts, each one built by a different company, and supervised by an independent consortium. There were up to 3,300 workers simultaneously on the project, which took 18 months of preparation and another 18 months of construction.
The bridge has a life expectancy of 120 years, having been designed to withstand wind speeds of 250 km/h (155 mph) and hold up to an earthquake 4.5 times stronger than the historical 1755 Lisbon earthquake (estimated at 8.7 on the Richter scale). The deepest foundation piles, up to 2.2 m (7.2 ft) in diameter, were driven down to 95 m (312 ft) under mean sea level. Due to the bridge's length, it was necessary to take the Earth's curvature into account to site the piers correctly, otherwise a deviation of 80 cm (31 in) would be apparent at either end of the bridge. Environmental pressure throughout the project resulted in the left-bank viaducts being extended inland to preserve the marshes underneath, as well as the lamp posts throughout the bridge being tilted inwards so as not to cast light on the river below.
The cost of the bridge came at zero to the State, as it was built in the BOT (build-operate-transfer) system by Lusoponte, a private consortium which got a 40-year concession on the tolls of both Lisbon bridges. Lusoponte's capital is 50.4% from Portuguese companies, 24.8% French and 24.8% British.
As of 2009, the toll is €2.40 per passenger car (up to €10.80 per truck) northbound (into Lisbon). There is no toll for southbound traffic.
The bridge has a life expectancy of 120 years, having been designed to withstand wind speeds of 250 km/h (155 mph) and hold up to an earthquake 4.5 times stronger than the historical 1755 Lisbon earthquake (estimated at 8.7 on the Richter scale). The deepest foundation piles, up to 2.2 m (7.2 ft) in diameter, were driven down to 95 m (312 ft) under mean sea level. Due to the bridge's length, it was necessary to take the Earth's curvature into account to site the piers correctly, otherwise a deviation of 80 cm (31 in) would be apparent at either end of the bridge. Environmental pressure throughout the project resulted in the left-bank viaducts being extended inland to preserve the marshes underneath, as well as the lamp posts throughout the bridge being tilted inwards so as not to cast light on the river below.
The cost of the bridge came at zero to the State, as it was built in the BOT (build-operate-transfer) system by Lusoponte, a private consortium which got a 40-year concession on the tolls of both Lisbon bridges. Lusoponte's capital is 50.4% from Portuguese companies, 24.8% French and 24.8% British.
As of 2009, the toll is €2.40 per passenger car (up to €10.80 per truck) northbound (into Lisbon). There is no toll for southbound traffic.
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