standard Ponte 25 de Abril , Lisbon’s bridge

The 25 de Abril Bridge (Ponte 25 de Abril “25th of April Bridge”), is a suspension bridge connecting Lisbon, capital of Portugal, to the municipality of Almada on the left bank of the Tejo River.

25 de Abril Bridge

Ponte 25 de Abril

It was inaugurated on August 6, 1966 and a train platform was added in 1999. Because of its similar coloring, it is often compared to the Golden Gate Bridge in San Francisco, USA. In fact, it was built by the same company (American Bridge Company) that constructed the San Francisco-Oakland Bay Bridge and not the Golden Gate, also explaining its similarity in design. With a total length of 2,277 m, it is the 20th largest suspension bridge in the world. The upper platform carries six car lanes, the lower platform two train tracks.

In 2006 a daily average of 150,000 cars cross the bridge, including 7,000 on the peak hour. Rail traffic is also heavy, with a daily average of 157 trains. In all, around 380,000 people cross the bridge daily (190,000 if considering return trips).

25th April Bridge and boat

25th April Bridge and boat

While going over the bridge you have this fantastic panoramic view of Lisbon. You can see a few landmarks in the distance if you have a tour guide that points it out to you.

History and description

The current suspension bridge opened in 1966 at a cost of 32 million US dollars. Originally, it was named the Ponte Salazar (after the then prime minister/dictator of Portugal, António de Oliveira Salazar). This bridge was renamed the 25th April Bridge (Ponte 25 de Abril) after the 1974 Portuguese Revolution, which started on that date, so as to remove any reference to the former dictator.

The bridge is 2.278km long between its anchorages with the main span being 1.013km long. The bridge originally opened (1966) as a four lane road bridge with a central barrier but the barrier was removed in 1990 to accommodate a fifth lane. The bridge leaves western Lisbon at high level above the Alcântara valley and makes landfall at Almada on the southern bank of the river, adjacent to the Cristo Rei monument (a smaller variant of the Brazilian original in Rio de Janeiro). The bridge, when built, had the longest central span of any European suspension bridge. However, both the more recent Humber Bridge (UK) and Bosphorus Bridge are amongst those that are now longer.

25 de Abril Bridge- Night view

25 de Abril Bridge- Night View

The bridge crosses the Tagus at a height of 70m. and its foundations on the Lisbon side, at 79m. deep into basalt rock, were also a world record at the time of their sinking.

The bridge itself provides good views over Lisbon, of the Lisbon docks and of the Cristo Rei (Christ the King) monument at Almada, which commemorates Portugal’s survival of World War II without the country’s direct involvement. Down river can also be clearly seen the Torre de Belém.

Design

The 25 de Abril Bridge is based on the San Francisco – Oakland Bay Bridgenear the Golden Gate Bridge in San Francisco, USA. Both SFOBB and the 25 de Abril Bridge were built by the same company. The American Society of Civil Engineers says that “Like its sister bridge, the SFOBB in San Francisco, the Tagus River Bridge is located in an area with a long history of earthquakes” and seismic data had to be taken into account in its construction. Another sister bridge is the Forth Road Bridge in Edinburgh.

Lisbon-25de Abril Bridge- Sunset View

Lisbon-25de Abril Bridge- Sunset View

Upon completion the bridge had the longest suspended span and the longest main span in Continental Europe, the world’s longest continuous truss, and the world’s deepest bridge foundation. It was the fifth largest suspension bridge in the world, the largest outside the USA. Today it is the 20th largest suspension bridge in the world. It looks great , but take a look at Ponte Vasco da Gama , the other great Lisbon’s bridge , you’ll be surprised .

Ponte 25 de Abril - car view

Ponte 25 de Abril - Car View

Dimensions

  • 1012,88 m – length of main span
  • 2277,64 m – length of truss
  • 70 m – height from water to upper platform
  • 190,47 m – height of main towers (second tallest structure in Portugal)
  • 58,6 cm – diameter of each of the two sets of main cables
  • 11,248 – number of steel wire strand cables, each 4,87 mm in diameter, in each set of main cables
  • 54,196 km – length of steel wire strand cables making up the two sets of main cables
  • 79,3 m – depth (below water-level) of the foundation of the south pillar
  • 30 km – length of access roads
  • 32 – viaducts in the access roads

[article source: www.wikipedia.org]

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