Bayonne Bridge

The Bayonne Bridge is the fifth-longest steel arch bridge in the world, and was the longest in the world at the time of its completion.

The bridge became a National Historic Civil Engineering Landmark in 1985. Ammann, the master bridge builder and chief architect of the Port Authority, chose the steel arch design after rejecting a cantilever andsuspension design as expensive and impractical for the site, given a requirement by the Port Authority that the bridge must be able to accommodate the future addition of rapid transit tracks.The eventual design of the bridge called for a graceful arch that soars 266 feet (69 m) above the Kill Van Kull and supports a road bed for 1,675 feet (511 m) without intermediary piers. The total length of the bridge

The arch resembles a parabolabut is made up of 40 linear segments. The design of the steel arch is influenced by theHell Gate Bridge designed by Ammann's mentor, Gustav Lindenthal Gilbert had designed an ornamental granite sheathing over the steelwork as part of the original proposal, but as in the case of the George Washington Bridge, the stone sheathing was eliminated in order to lower the cost of the bridge, leaving the steel posed. It was the first bridge to employ the use of manganese steel for the main arch ribs and rivets.Construction on the bridge began in 1928, and eventually cost $13 million. When it opened on November 15, 1931, it was the longest steel arch bridge in the world. It maintained that distinction after the 1932 opening of the Sydney Harbour Bridge, whose arch is much more massive but 24 feet shorter. The Bayonne Bridge's dedication ceremony was attended by David M. Dow, the Secretary for Australia in the United States, and the same pair of golden shears used to cut the ribbon was sent to Australia for the ribbon-cutting of the Sydney Harbour Bridge. After the ceremony in Sydney, the scissor blades were separated and one

The work, begun in July 2013, will raise the road deck by 64 feet (19 m), create 12-foot wide lanes, including a bicycle and pedestrian lane, and install a median divider and shoulders. This would raise the bridge's clearance to 215 feet (66 m) by building a new roadway above the existing roadway within the current arch structure. A gantry crane rolling on top of the arch will construct one rope-supported section of the new roadway at a time, using a temporary beam to support the existing roadway while each rope is replaced.The existing roadway will then be removed. The Port Authority believes it is possible to build the new roadway without interrupting traffic flow between Staten Island and Bayonne. In July 2012 the Port Authority announced construction would begin in Summer 2013, to be completed by late 2016. In this timeline, removal of the existing roadway would be completed by late 2015, in time for the opening of the widened Panama