| Bridge Name: | Octávio Frias de Oliveira Bridge |
| Native Name: | Ponte Octávio Frias de Oliveira |
| Native Name Lang: | pt |
| Carries: | two oppositely curved roadways, three lanes each |
| Other Name: | Ponte Estaiada |
| Crosses: | Pinheiros River |
| Locale: | São Paulo, Brazil |
| Design: | Cable-stayed bridge[1] |
| Mainspan: | 150m (490feet) for each roadway; 290m (950feet) total cable-stayed spans for each roadway |
| Length: | total for two roadways |
| Width: | 16m (52feet) for each roadway |
| Height: | 138m (453feet) (X-shaped tower) |
| Begin: | 2005 |
| Complete: | May 2008 |
| Material: | Concrete sustained by stainless steel cables, coated with polyethylene resistant to sunlight |
| Mapframe-Zoom: | 13 |
The Octavio Frias de Oliveira bridge, locally known simply as "Ponte Estaiada" (Portuguese: lit. 'Bridge Cable-stayed'), is a cable-stayed bridge over the Pinheiros River in the city of São Paulo, Brazil, opened in May 2008. The iconic bridge has an "X"-shaped tower, tall, and connects the west end of Jornalista Roberto Marinho Avenue to the riverside expressway Marginal Pinheiros in the south area of the city. It is named after businessman Octavio Frias de Oliveira.
The bridge is composed of two cable-stayed curved roadways suspended from a single concrete "X"-shaped tower or pylon. It is the only bridge in the world that has two curved roadways supported by a single pylon.[2]
The bridge, conceived by the São Paulo Municipality City Hall,[3] was designed by engineers of the "Enescil Engenharia e Projetos Ltda". The preliminary design called for two separate cable-stayed bridges, each suspending a curved roadway from its mast (pylon) inclined outwardly from the axis of curvature to provide balance and minimum torsion on its mast. More importantly, the two oppositely curved roadways crossed over each other. The critical step in the engineering design was to make the crossover of the two roadways occur vertically below both inclined masts, which led to the two oppositely inclined masts intersecting, bracing each other, forming a single "X"-shaped tower as the central support of the bridge.[4] After the engineering design was established, "Valente e Valente Arquitetos" softened the contours and provided the finishing touches of the work.[5]
In 2005, construction began under the company "Construtora OAS Ltda". After three years of construction, the bridge was inaugurated on 10 May 2008. The total cost, including illumination, came to R$233 million.[6]
The "X"-shaped tower is anchored onto the east bank of the Pinheiros River at the end of the Jornalista Roberto Marinho Avenue; it is 138 meters high, 76 meters wide at its base and 35.4 meters wide at the top. The cable-stayed bridge deck is unique due to its complex form: two curved roadways with constant radius of 275.1 meters, oppositely curved, crossing over near the base of the tower, one at an elevation of 12 meters and the other at an elevation of 24 meters, each supported by a strut between the two legs of the X-shaped tower. Both roadways have cable-stayed spans of 140 meters on the Roberto Marinho Avenue side and 150 meters on the Marginal Pinheiros side, for a total of four cable-stayed spans. The curved edge beams of each cable-stayed span are connected to its outwardly inclined arm of the X-shaped tower by 18 pairs of stay cables, for a total of 144 stay cables.[7] On the curved cable-stayed spans over the Pinheiros River, the stay cables are interlaced, creating a crisscrossing geometric arrangement not found in any other cable-stayed bridge in the world.
At the end of December, lights are put up on the cables and illuminated to create color effects like those on a Christmas tree. The bridge is also lit up on special occasions during the year and is often used for automobile advertisements on television.
Although the Bridge is a well-known sight, it takes intentional effort to see it up close because only motor vehicles are allowed on it.[8] To drive through one of the two cable-stayed curved roadways of the Bridge, one needs either to be westbound on Roberto Marinho Avenue and head southbound on Marginal Pinheiros or to be southbound on Marginal Pinheiros and head eastbound on Roberto Marinho Avenue. Alternatively, the Bridge area by the River can be accessed by bicycle or by foot, although the Pinheiros River is polluted.[9]
The bridge has been attacked by vandals on several occasions. In 2011, thieves stole 6km (04miles) of wire, worth R$200,000 (US$117,000).[10] Later in August, vandals broke in the bridge's control room and destroyed the panels.[10] On January 9, 2012, vandals stole 94 of the 142 searchlights of the bridge.[10] It will take 90 days and R$1,000,000 (around US$250,000) to completely re-establish the lighting system.[10]