Queensferry Crossing is the third bridge across the Firth of Forth, the mouth of the Forth River. The very first there was the railway Fort Bridge of the late 19th century (now a UNESCO monument). In 1964, the automobile Fort Road Bridge was put into operation: it was opened by Elizabeth II, and exactly 53 years later, on September 4, 2017, she opened the Queensferry Crossing.
The need to build a new estuary bay bridge became clear in 2004 when the steel cables of the Fort Road Bridge were found to lose 8-10% strength due to corrosion. This suspension bridge, the longest in the world at the time of opening, was used every day by 60,000 vehicles, and even its temporary closure would entail great difficulties for the Scottish economy and the entire country: 85% of goods in the United Kingdom are transported by trucks. In 2007, after a large-scale study, the Scottish Cabinet of Ministers decided to build another bridge nearby - to reduce the load on the Fort Road Bridge (and as a backup during the necessary repairs). Queensferry crossing (the name was chosen as a result of popular vote, citizens in its course proposed 7,600 variants of the "name" for the bridge) opened 10 years later, which is a very short time for a project of this magnitude. The current load of the bridge is 24 million vehicles per year; after its opening, the Fort Road Bridge was completely given over to public transport, cyclists and pedestrians.
The Jacobs Arup team acted as government consulting engineers, with 1.9 million man-hours and experts, including from branches from other continents. The general contractor was designed by an amalgamation of Ramboll, SWECO and Leonhardt Andra und Partner, and the general contractor was a consortium of Hochtief, American Bridge, Dragados and Morrison, whose specialists in total gave Queensferry-crossing more than 10 million working hours.
Two viaducts, 543 and 222 meters long, respectively, lead to the bridge. The bridge itself covers 2.7 km, its three towers reach a height of 210 m. In total, the bridge complex is 22 km long, since it includes specially rebuilt road sections leading to it.
Taking into account the harsh climate of the Scottish coast of the North Sea, travelers on the bridge are protected from the wind by fences with a height of 3.5 m. The state of the Queensferry crossing is monitored by 1,500 sensors that record how it copes with the load at different temperatures, humidity, and wind strength. There are anti-corrosion moisture removal systems and various elevators, monorail, etc., simplifying any preventive and repair work.
During the construction, world records were set for underwater concrete pouring (16 869 m3 in 24 hours without a break during the construction of the south tower) and balanced hinged installation (from the central tower, spans were extended by 322 m in each direction - a total of 644 m - to their connections to the rest of the structure).
