STICK will attempt to send out entertaining and informative items on various subjects of interest to our network. We will also be using social media such as Twitter to keep in touch.
Today, conservation engineering with a follow up on STICK Knowledge & Fun 13 and 15 with a progress report by Prof. Roland Paxton (Heriot-Watt University) on restoration and conservation work being carried out at the Union Chain Bridge near Berwick Upon Tweed (see STICK Knowledge & Fun 13 - Union Bridge (campaign-archive.com)
). This bridge is the the world’s oldest vehicular suspension bridge, longest span when built in 1820 and designed by the visionary engineer Samuel Brown.
For more information on the work on the ICE Panel for Historical Engineering Works see Historical engineering works | Institution of Civil Engineers (ice.org.uk)
Progress Report on the Restoration of Union Chain Bridge, 30 November 2020
For several decades the Institution of Civil Engineers (ICE) via its Panel for Historic Engineering Works (PHEW), Heriot-Watt University, and since 2014, The Friends of Union Chain Bridge
[now numbering 690] and also the American Society of Civil Engineers (ASCE) and Japan Society of Civil Engineers (JSCE) Committees have strongly supported the preservation of Union Bridge for posterity as a world-class landmark in long span suspension bridge development. Its deterioration since 2010 has caused much concern, to remedy which £10.5m of hard-won funding has been raised from 11 organisations and others for its restoration.
On 1 July 2020 a £7.1m contract for the bridge’s restoration was entered into by the bridge owners with The Spencer Group of Hull and work on site commenced on 1st
October. Completion is programmed for November 2021. Spencer’s have had experience of this kind of project as exemplified in their restoration of Sir John Rennie’s 1835 Horkstow suspension bridge, which in 1999 attracted a ‘commendation’ from the national Historic Bridge and Infrastructure Awards
Panel for which I was an adjudicator.
Because of the Covid-19 pandemic the bridge’s bicentenary on 26 July 2020 turned out to be a low key, very local, celebration which included a preview of the International Historic Civil Engineering Landmark (IHCEL) Plaque shown below, the obtaining of which I undertook to put in train at The Friends
inaugural meeting in 2014. Hopefully the plaque will be formally dedicated in due course, an outcome The Friends
will encourage. Sadly, all the officially planned bicentenary engagements, including the Plaque Unveiling and Symposium, had had to be cancelled. Fortunately, the substance of the planned Symposium has survived in Spanning the Centuries
published in July [available from the Friends of Union Bridge
Preview of the IHCEL Plaque on 26 July by Ted Cawthorn and Robbie Hunter, Secretary and Chairman of the Friends of Union Chain Bridge. Image: Friends of Union Change Bridge.
The plaque carries ASCE, ICE and JSCE recognition for Union Chain Bridge on an International Historic Civil Engineering Landmark Plaque. Image: Friends of Union Change Bridge.
The estimate for making the Landmark Plaque was nearly twice ASCE’s budget causing concern with the tight timescale! This problem was met by a rapid re-consideration of its wording to the absolutely acceptable minimum and commitments from JSCE, PHEW Scotland and The Friends
to meet a shortfall of £1249/$1685. The result is spectacular and a credit to all concerned. The bridge’s international recognition was enhanced by having the Japan Society of Civil Engineers as a co-sponsor, its first association with an IHCEL Plaque. There is international interest in the bridge. Dr. Henry Petroski (Duke University, USA) has written an article on Union Chain Bridge which will appear in the next issue of American Scientist
Right: The temporary steel Scottish bank winch tower on 25 November 2020. The tower is founded at ground level, its sides can be seen through the arch.
Image: Friends of Union Change Bridge.
Above: Base of steel tower for cable and anchor drilling equipment
support and renovation and replacement of tower masonry as at 25 November 2020. Image: Friends of Union Change Bridge.
The restoration contract is understood to be going well despite the contractor’s team having to cope with Covid-dictated restrictions. Work is now progressing on Stage 6 - the construction of towers to support winches for the removal and re-erection of the historic chains. The present state of work is indicated in the following photographs, courtesy of The Friends
. It can be seen from comparing these images with Northumberland County Council’s proposed modus operandi
above [Spanning the Centuries
p.39], that amendments in detail have been made.
Hon Professor, Institute for Infrastructure and Environment, Heriot-Watt University.
Patron, The Friends of Union Chain Bridge;
Emeritus Member ICE - PHEW
30 November 2020
The STICK Committee