timeline item
Results
Here is the information we have
on the item you selected
More like this
NEW SEARCH
| |
sign up for our newsletter
© 2017 Engineering Timelines
engineering-timelines@severalworld.co.uk
engineering timelines
explore ... how   explore ... why   explore ... where   explore ... who  
home  •  NEWS  •  search  •  FAQs  •  references  •  about  •  sponsors + links
Union Bridge
River Tweed, just north of Horncliffe, Northumberland, UK
Union Bridge
associated engineer
Captain Sir Samuel Brown
date  2nd August 1819 - 26th July 1820
era  Georgian  |  category  Bridge  |  reference  NT933510
ICE reference number  HEW 143
photo  Jane Joyce
Union Bridge, a wrought iron cable chain suspension bridge, crosses the River Tweed between England and Scotland. It was the first of its kind completed in Britain and remained the longest for five years.
The bridge was built by Captain (later Sir) Samuel Brown RN, who patented his design for the wrought iron chains. The original plans for the tower and abutments were improved on the advice of John Rennie (1761-1821). It spans 133m between the rock anchorage at its south end and the 18.3m tall masonry pylon at its north end, which gives a clear span of 110m.
There are three pairs of chains dipping about 8m, one above the other, on each side of the deck. Individual chains are formed from 4.6m by 50mm diameter eye-bar links. This technique was developed further by Thomas Telford on the Menai Bridge, completed in 1826.
Union Bridge cost some 7,700 to construct, around one third of the cost of a multi-span masonry arch bridge of similar length.
The 5.5m wide timber deck was refurbished in 1871 and in 1974. In 1902-3 a steel cable was added to each side with steel hangers, to give continued support if one of the iron chains fails. The worn connecting links between the main eye-bars were replaced with spheroidal graphite iron links in 1974.
The bridge was designed to move under loading but after some extreme displacement in 1953 work was done to restrict vertical movement to some 150mm. Traffic was later limited to one vehicle on the bridge at a time.
In spring 2007, the bridge was closed for several months when one of the hangers broke. Then in December 2008 a landslide forced closure again. Repair work started in June 2009.
Tweed Bridges Trust has maintained Union Bridge since the abolition of turnpike tolls in 1883. It is a Grade I listed building and a Scheduled Ancient Monument.
Research: ECPK
bibliography
"Historic bridge closes after faults discovered"
Berwick Advertiser, Berwick-upon-Tweed, England, 5th April 2007
http://ltp.northumberland.gov.uk
http://unionchainbridge.blogspot.com
www.chainbridgehouse.co.uk
reference sources   CEH SLB
Location

Union Bridge