George Washington Bridge

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Coordinates: 40 ° 51 ′ 7 ″  N , 73 ° 57 ′ 15 ″  W.

I-95.svg George Washington Bridge
George Washington Bridge
Official name George Washington Bridge
use Motor vehicles ( I-95 / US 1 / US 9 / US 46 ; 8 + 6 strips), pedestrians, cyclists
Crossing of Hudson River
place New York City and Fort Lee, NJ
Entertained by Port Authority of New York and New Jersey
construction Double-decker suspension bridge
overall length 1451 m
width 36 m
Longest span 1067 m
Headroom 4.27 m (upper level),
4.11 m (lower level)
Clear height 65 m
vehicles per day ≈ 275,000
opening October 24, 1931 (above)
August 29, 1962 (below)
planner Othmar Ammann
location
George Washington Bridge (New York City)
George Washington Bridge
George Washington Bridge

The George Washington Bridge ( George Washington Bridge , colloquially GWB , GW Bridge or GW for short ) is a suspension bridge over the Hudson River in New York City , which connects Manhattan with New Jersey . The road bridge with a total of fourteen lanes is considered to be the busiest bridge in the world. It is named after George Washington , the first President of the United States . When it opened in 1931, the bridge planned and built by Othmar Ammann had the largest span in the world.

location

The George Washington Bridge crosses the Hudson River, which flows between steep, 30 m high banks, between Washington Heights in northern Manhattan and Fort Lee , Bergen County , New Jersey , on the mainland side. Fort Washington used to be in the immediate vicinity at the highest point of Washington Heights and Fort Lee on the other side.

It is the only bridge between Manhattan Island and the mainland west of the Hudson. Only the Holland Tunnel and the Lincoln Tunnel offer further direct road connections to New Jersey. Downstream there is only the Verrazzano-Narrows Bridge between Brooklyn and Staten Island , upstream the Tappan Zee Bridge, around 25 km further north, is the next bridge over the Hudson River.

traffic

The George Washington Bridge is part of Interstate 95 from Florida to Maine . The I-95 leads as the New Jersey Turnpike in a large arc from the west to the bridge, on the other side crosses Manhattan as a twelve-lane Trans-Manhattan Expressway in a trough and crosses the Harlem River to the Bronx on the Alexander Hamilton Bridge , where it becomes the Cross Bronx Expressway will. The US Highway 1 and US Route 9 also walk across the bridge, which also houses the local traffic over various access roads.

Traffic flows through eight lanes on the upper level and six lanes on the lower level, with trucks only allowed to use the upper level. There is a speed limit of 45 mph (72 km / h), but the actual speed is often lower due to heavy traffic. In 2012, 49,110,921 vehicles crossed the bridge in the direction of New York, so that the bridge is used by around 100 million vehicles per year.

The bridge is toll road in the direction of New York , the journey from New York to New Jersey is free. According to the 2012–2015 toll rate schedule , the fee for crossing the bridge for motorcycles is $ 12 for cash payments, $ 9.25 for a single pass during commuter times (peak) and $ 7.25 at off-peak times and for cars $ 13 bar and $ 10.25 EZ-Pass (peak) and $ 8.25 EZ-Pass off-peak. There are also discounts for cars that are occupied by at least three people or that have good emissions. For trucks, different tariffs apply depending on the time of day or night and the number of axles between $ 19 (2-axle, at night, with single pass) and $ 90 (6-axle semi-trailer, cash payment). Pedestrians and cyclists can cross the bridge free of charge; they share the path on the south side, which is open from 6 a.m. to midnight. The path on the north side of the bridge is usually closed unless maintenance work requires another regulation.

description

The George Washington Bridge was built according to the plans and under the direction of Othmar Ammann , inaugurated on October 24, 1931 and opened to traffic on October 25.

Their total length is 1451 m (4760 ft), measured from one anchorage of the suspension cables to the other. Since the bridge connects the areas above the high cliffs of the Hudson River, no long access ramps were required and the roadway on the bridge could be kept relatively flat. The short bridge spans between the banks and the pylons (192 m for the New York side and 186 m for the New Jersey side) explain that the suspension cables outside the pylons drop unusually steeply to their anchorages. The bridge has a headroom above the mean flood of the Hudson River of 64.6 m (212 ft).

The span is 1067 m (3500 ft), which at the time of its opening was a new world record and far exceeded the largest span of the Ambassador Bridge (564 m). In 1937 it was replaced by the Golden Gate Bridge with a span of 1280 m.

Her two pylons are made from a plain-looking steel - truss structure . They are 184 m (604 ft) high, 64 m wide and 17 m thick and with these dimensions they are still unique. Its pillars are connected in the upper third above the carriageway by trusses and round arches to form portals , the opening of which corresponds to the width of the carriageway girder . The pillars are also connected and stiffened by round arches under the girder. The pylon on the New York side stands directly on the bank, the pylon on the other side just in front of the bank in the water. The pylons were originally intended to be clad with granite or prestressed concrete slabs, but this was not done because of the sharp rise in construction costs as a result of the global economic crisis . The steel girder construction was nevertheless described in the professional world as elegant and fascinating and the bridge thus became a forerunner of modernity.

The deck beam is 36 m (119 ft) wide. The eight-lane carriageway in the middle of the upper level is 27.4 m wide. The difference of around 4.3 m on both sides is due to the space required for the suspension ropes.

Support ropes of the GW Bridge

The bridge has four suspension cables, two on each side of the roadway. The suspension ropes are parallel wire ropes produced on the bridge using the air-jet process . Each of the ropes consists of 26,474 individual wires . 434 wires were combined into 61 strands, which were arranged in a hexagonal profile and formed into round, almost 91 cm thick suspension ropes by hydraulic presses and then coated to prevent corrosion. The supporting ropes lie on the pylons in rope saddles weighing 162 tons (180  tn. Sh. ), Which were originally arranged openly on the pylon tops, but were covered after two years. The suspension cables are anchored directly in the rock on the New Jersey side, but in large concrete anchor blocks on the New York side.

The George Washington Bridge was designated a National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1981.

On holidays Martin Luther King Day , Memorial Day , Independence Day , Labor Day , Washington's Birthday , Columbus Day , Flag Day and Veterans Day is the pillar on the New Jersey the largest free-blowing side America flag in the world (30 m × 20 m , 215 kg).

North of the bridge on the New Jersey side is the Palisades, a wooded cliff. Building on the strip visible from the Hudson is forbidden for 15 miles. This was ordered by the owner John D. Rockefeller II , who wanted to protect the view from the “ The Cloisters ” museum in New York. Rockefeller bought the museum for the Metropolitan Museum of Art in New York in 1925 .

history

Since the end of the 19th century there have been various proposals for bridging the Hudson River, including various designs by Gustav Lindenthal , who wanted to connect Midtown Manhattan and New Jersey with a road and rail bridge that would have been significantly larger than today's bridge, but was not carried out for lack of money. Othmar Amman had worked on the design as Lindenthal's employee, but soon developed his own ideas.

After separating from Lindenthal, Ammann proposed a pure road bridge further north at Fort Lee, where the cost of purchasing land was significantly lower and the Hudson was narrower. In order to further reduce costs, it should initially only have one level for six lanes and two wide sidewalks, but be designed in such a way that two lanes could be added later and a second level could be added for motor vehicles and railroad trains in suburban traffic. This enabled him to propose a bridge that would cost significantly less and be politically easier to implement than the bridges offered by Lindenthal and other competitors.

Ammann's ideas were accepted; the newly established Port Authority of New York and New Jersey decided in 1925 to build the bridge and hire Othmar Amman as chief engineer for the planning and construction of the bridge. Cass Gilbert was commissioned to provide architectural advice. The planning of the cladding of the pylons with granite slabs goes back to him.

Ammann's final design was revolutionary in many respects: the span of the bridge was almost twice as large as that of the longest bridge built up to that point, and the deck girder had no large trusses to stiffen it. According to the deflection theory , which was first applied by Leon S. Moisseiff to large suspension bridges at the Manhattan Bridge , the weight of the suspension cables and the bridge deck would neutralize a large part of the lateral wind pressure; A low wind resistance of the flat deck girder is important. Ammann, who had dealt intensively with this theory and was also advised by Moisseiff, was convinced that the four supporting cables, the great width of the bridge deck and their extraordinarily high weight due to the span were sufficient to withstand even heavy storms. In addition, there was the stiffness of the wide and thick pylons and the short outer bridge fields with the steeply sloping supporting cables.

GW Bridge 1956 still with the flat deck and the USS Nautilus

The first groundbreaking for the construction of the Hudson River Bridge , as it was originally called, took place on September 21, 1927. After the construction of the pylons and the anchors, the wires supplied by John A. Roebling and Sons were converted into four by 300 workers in 209 working days Spinning ropes to which the suspension ropes were attached. The suspension of the sections of the bridge deck began on the pylons, so that the last section above the middle of the river closed the roadway. In 1930 the Port Authority decided to name the bridge the George Washington Memorial Bridge ; later this was simplified to the current name.

The bridge was inaugurated on October 24, 1931 by Governors Franklin D. Roosevelt , New York, and Morgan F. Larson , New Jersey - eight months ahead of the agreed date and well below budget.

Even after the collapse of the somewhat shorter, but with only two lanes, significantly narrower and lighter Tacoma Narrows Bridge in November 1940, Othmar Ammann was firmly convinced that his bridge was stable enough to withstand the dynamic wind forces that had not been properly understood until then . Practice confirmed his view, the bridge showed hardly any vibrations.

In 1946, as planned from the start, the carriageway was expanded from six to eight lanes. From 1959 to 1962, at the instigation of Robert Moses, the second level below the original, which was also planned from the beginning, was added, while traffic continued unchanged on the top eight lanes. This inevitably gave the bridge a girder that consisted of a high framework construction, so that its rigidity has not been in doubt since then.

Between 1977 and 1978 the old concrete pavement on the upper level was replaced by an orthotropic slab . The prefabricated, 3.35 m × 18.30 m (11 ft × 60 ft) elements, which had already been covered with the road surface, were installed at night. In this way, the rush hour traffic could flow unhindered again the next morning. This was also one of the first uses of an orthotropic plate to reinforce a larger suspension bridge.

Web links

Commons : George Washington Bridge  - Collection of Images, Videos, and Audio Files

literature

  • Michael Aaron Rockland: The George Washington Bridge: Poetry in Steel. Rutgers University Press, New Brunswick 2020, ISBN 978-0-8135-9461-3 .

Individual evidence

  1. ^ 3sat documentary: Gateways to New York - Othmar H. Ammann and his bridges. ventura film 2018.