timeline item
Here is the information we have
on the item you selected
This entry was funded by
More like this
sign up for our newsletter
© 2018 Engineering Timelines
engineering timelines
explore ... how   explore ... why   explore ... where   explore ... who  
home  •  NEWS  •  search  •  FAQs  •  references  •  about  •  sponsors + links
Tower Bridge
River Thames, beside the Tower of London
Tower Bridge
associated engineer
Sir John Wolfe Barry
Henry Marc Brunel
date  April 1886 - 30th June 1894
era  Victorian  |  category  Bridge  |  reference  TQ335803
ICE reference number  HEW 31
photo  Jane Joyce
The symbol of London, Tower Bridge is a low-level bascule bridge, openable for ship traffic, with a high-level walkway above. The original lifting mechanism was a steam-driven hydraulic system.
Although the bridge appears to be made of stone, it is in fact a steel-framed structure with granite and Portland stone cladding. Each tower has four steel columns, 19ft 6in high and made from plates, angles and Ts. Their octagonal steel base-plates are 14ft across, bedded into stone bases 16ft square and 3ft thick.
The metalwork was shipped from Glasgow and transferred to barges half a mile downstream, at the rate of 50 to 100 tons a week. However, no single piece weighed more than 5 tons. In all, 11,00 tons of steel, 1,200 tons of cast iron and 580 tons of lead were needed.
The towers sit on two massive river piers, each 70ft wide by 184ft 4in. They provide a clear navigation width of 200ft. During construction, a clear navigation width of 160ft had to be maintained at all times, which delayed the work considerably.
The original hydraulic system (for lifts and bascule operation) consisted of a pumping station on the south shore with two double tandem compound steam engines, powered by four Lancashire boilers. In addition, two hydraulic accumulators boosted power when the bridge had to be opened. The high pressure water went out to the river piers, which housed the hydraulic motors.
The system was converted to electro-hydraulic operation in 1974 and the steam plant decommissioned. The engineers for this were Mott, Hay and Anderson.
Horace Jones was the City Architect in the 1870s and his design was chosen over others, including three by Bazalgette, as the City of London insisted on using its own architect and clinched the deal by finding the money.
Barry teamed up with Henry Marc Brunel for this project. Brunel provided the detailed design calculations for the steelwork.
Architect: Sir Horace Jones
Piers, abutments and northern approach works: Sir John Jackson Ltd
Southern approach works: William Webster
Steel superstructure: Sir William Arrol & Co
Engineers with Arrol: James Tuit, Adam Hunter
Masonry contractor: Perry & Co
Hydraulic machinery: Sir William Armstrong, Mitchell & Co
reference sources   CEH Lond

Tower Bridge