Crossbeams run between the trusses at the top, and diagonal and vertical stiffening beams run on the outside and inside of each roadway. These trusses are held up by suspender ropes, which hang downward from each of the four main cables. The trusses allow the Brooklyn Bridge to hold a total load of 18,700 short tons (16,700 long tons), a design consideration from when it originally carried heavier elevated trains. The main span and side spans are supported by a structure containing six trusses running parallel to the roadway, each of which is 33 feet (10 m) deep. However, due to a supplier's fraudulent substitution of inferior-quality cable in the initial construction, the bridge was reappraised at the time as being only four times as strong as necessary. This is because John Roebling designed the Brooklyn Bridge's truss system to be six to eight times as strong as he thought it needed to be.
It was coincidental that the open truss structure supporting the deck is, by its nature, subject to fewer aerodynamic problems. At the time of construction, engineers had not yet discovered the aerodynamics of bridge construction, and bridge designs were not tested in wind tunnels. The side spans, between each suspension tower and each side's suspension anchorages, are 930 feet (280 m) long. A 1909 Engineering Magazine article said that, at the center of the span, the height above MHW could fluctuate by more than 9 feet (2.7 m) due to temperature and traffic loads, while more rigid spans had a lower maximum deflection. Navigational clearance is 127 ft (38.7 m) above mean high water (MHW). The bridge "elongates and contracts between the extremes of temperature from 14 to 16 inches". The main span between the two suspension towers is 1,595.5 feet (486.3 m) long and 85 feet (26 m) wide. A separate measurement of 5,989 feet (1,825 m) is sometimes given this is the distance from the curb at Centre Street in Manhattan. Including approaches, the Brooklyn Bridge is a total of 6,016 feet (1,834 m) long when measured between the curbs at Park Row in Manhattan and Sands Street in Brooklyn. To provide sufficient clearance for shipping in the East River, the Brooklyn Bridge incorporates long approach viaducts on either end to raise it from low ground on both shores.
The Brooklyn Bridge has been designated a National Historic Landmark, a New York City landmark, and a National Historic Civil Engineering Landmark.Īn approach ramp to the Brooklyn Bridge, seen from Brooklyn, with Manhattan Bridge (partially hidden by buildings) seen in the background Over the years, the bridge has been used as the location of various stunts and performances, as well as several crimes and attacks. A major tourist attraction since its opening, the Brooklyn Bridge has become an icon of New York City. Only passenger vehicles and pedestrian and bicycle traffic are permitted. The Brooklyn Bridge is the southernmost of the four toll-free vehicular bridges connecting Manhattan Island and Long Island, with the Manhattan Bridge, the Williamsburg Bridge, and the Queensboro Bridge to the north. Following gradual deterioration, the Brooklyn Bridge has been renovated several times, including in the 1950s, 1980s, and 2010s. To alleviate increasing traffic flows, additional bridges and tunnels were built across the East River. Since opening, the Brooklyn Bridge has undergone several reconfigurations, having carried horse-drawn vehicles and elevated railway lines until 1950. Construction started in 1870, with the Tammany Hall-controlled New York Bridge Company overseeing construction, although numerous controversies and the novelty of the design prolonged the project over thirteen years. The project's chief engineer, his son Washington Roebling, contributed further design work, assisted by the latter's wife, Emily Warren Roebling. Proposals for a bridge connecting Manhattan and Brooklyn were first made in the early 19th century, which eventually led to the construction of the current span, designed by John A. The span was originally called the New York and Brooklyn Bridge or the East River Bridge but was officially renamed the Brooklyn Bridge in 1915. It was also the longest suspension bridge in the world at the time of its opening, with a main span of 1,595.5 feet (486.3 m) and a deck 127 ft (38.7 m) above mean high water. Opened on May 24, 1883, the Brooklyn Bridge was the first fixed crossing of the East River. The Brooklyn Bridge is a hybrid cable-stayed/ suspension bridge in New York City, spanning the East River between the boroughs of Manhattan and Brooklyn.
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