12 June 2014
Tyneside Bridges: 10. Redheugh Bridge
At last, this was the final bridge in the IABSE Study Tour of north-east England.
Completed in 1983 to a design by Mott, Hay and Anderson, the present Redheugh Bridge is on the site of two former crossings. The first was the most interesting: an innovative cable-stayed design by Thomas Bouch, which survived from 1871 to 1897.
Spanning 160m, the current bridge is a post-tensioned concrete box girder structure. An attractive steel box girder design had been proposed by MHA in 1966, but this was abandoned when a spate of failures of this type of bridge occurred, coinciding with a rise in steel prices which rendered a sufficiently strong design uneconomic.
The bridge has a twin-cell single box configuration, with utility services carried inside the box - gas pipes in one cell, and electricity cables and a water pipe in the other cell. Holes in the concrete box are provided for ventilation and as drainage in case the water main should leak.
The bridge was constructed using the balanced cantilever technique, with a series of 3m long in-situ concrete sections. It was completed a year after the Byker Metro Viaduct, another post-tensioned concrete balanced cantilever bridge built nearby. The Byker bridge was more innovative, being built using glued precast units, the first of its type in Britain, and I think it was also far more successful aesthetically. However, it's fair to note that the Byker bridge carries significantly lower loads, and has much shorter spans, so the pressure to adopt only the most economic solution will have been a little less.
That concludes my tour of bridges in the north east of England. I have a backlog of other bridges to report on here, and hope to start my next series of reports soon.