The work was divided among eight different contractors.
(afterwards Sir) John Wolfe Barry was appointed engineer. Horace Jones was appointed architect and was knighted, but died the same year, and Mr. The Tower Bridge is, perhaps, the most famous bascule bridge in the world, and its working from the day it was first opened to the present has been perfect, far exceeding the hopes even of its most enthusiastic advocates.Īn Act of Parliament empowering the Corporation of the City of London to build the bridge was passed in 1885. This was the type of bridge finally decided upon, and it has proved a great success. “Bascule” is derived from the French word for “see- saw”, and the bascule bridge is a kind of drawbridge which works on a pivot and has a heavy weight at one end to balance the greater length at the other. Successful bridges of this type already existed, though on a much smaller scale, at Rotterdam and Copenhagen. In 1878 Horace Jones, the City architect, put forward a proposal for a low- level bridge on the bascule principle - that is, a bridge on a level with the streets with two leaves or arms that could be raised to let ships pass up and down the river and lowered to let vehicles pass to and fro across the waterway.
Proposals for a subway and for large paddle- wheel ferry boats were also considered. There was also a proposal for a railway line to be built at the bottom of the river and to carry a travelling staging with its deck projecting above high- water level. These included schemes for low- level bridges with swing openings of various kinds, and high- level bridges with inclined approaches or with lifts at either end. A two days’ census taken during August 1882 showed that the average traffic for twenty- four hours over London Bridge - which at that time was only 54 feet wide - was 22,242 vehicles and 110,525 pedestrians.Ī committee was appointed to consider the matter and to report upon the different plans that had been proposed. By the year 1870 the position had become serious, and between 18 some thirty petitions from various public bodies were brought before the authorities urging either the widening of London Bridge or the building of a new bridge. The building of the Tower Bridge came about because the development of cross- Thames traffic had far outstripped the capacity of the existing bridges. It is the most distinctive of London’s bridges and its construction was a masterly engineering achievement. One of the most famous examples of the bascule type is the Tower Bridge, which spans the River Thames just below London Bridge. He surmounts the difficulty by resorting to the opening type of bridge, of which the main types are the drawbridge or bascule bridge, turning about a horizontal axis the swing bridge, turning about a vertical axis the rolling lift bridge and the vertical lift bridge. THE problem of building a bridge over a busy river with low banks so that shipping is not obstructed is one that taxes the resource and ingenuity of the engineer. A bascule bridge is a kind of drawbridge working on a pivot and balanced with a heavy weight. The central span, made up of two bascules, is 200 feet long. The two side spans are suspended, each span being 270 feet long.
In the Tower Bridge a combination of the suspension and bascule principles is used. THE BASCULE BRIDGE is eminently suitable for spanning a crowded waterway with low banks. Engineers were able to build this type of bridge without interrupting traffic on the great commercial waterway The most famous example of the bascule bridge is the Tower Bridge across the River Thames in the heart of London.
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