June 20th 1887 the "new" "Tay rail bridge opened, the longest in the British Isles.
Firstly  let’s get the usual dates thing out the way, I have three dates for this after examination, 1st, 10th and 20th of June, you’d think in an age where we photograph things for posterity, we could get the dates right. I’ve chosen today because it flagged up in my alerts, it’s as simple as that.
We have to salute the bravery of those men who worked building bridges like this, I say men, but look t the photos of the construction workers and see how young some of them were!
I think we all know the story behind the Tay bridge disaster so there is now need to go through it all again but after the bridge collapsed  the North British Railway and supporters of the Tay Bridge were determined that it should be rebuilt. William Henry Barlow who had sat on the board of  enquiry into the old bridge was asked on the best course of action. After thorough investigation of the options, his recommendation was to build a new double line bridge, completely independent of the old.
Barlow’s design for the new bridge was deeply influenced by the presence of the old. To satisfy stipulations made by the Board of Trade, the bridge was to be constructed exactly parallel alongside the old in order to keep navigation channels open, and its height was to be reduced from 88ft in the old bridge to 77ft in the new. As in the old bridge, the railway line was to run on the top of the approach girders, and through the girders of the high, larger navigation spans. Barlow recommended that if the spans of the new bridge were to be kept the same, girders from the old bridge that were unaffected by the collapse of the high girders, were able to be re-used in the new.
The new bridge was to be built 60ft upstream from the old, allowing the old bridge to become ‘staging’ for the men and materials in the construction of the new. The approaches onto the new bridge were altered; to the south the branch lines were joined on brick arches nearer to the shore at Wormitt, and to the North the eastwards curve into Tay Bridge Station (now called Dundee) was softened. Stringent tests on weight and wind loading in the design and construction of the new bridge were also to be undertaken. The proposals for the ‘New Tay Viaduct’ were accepted by Parliament in October 1881, and the firm William Arrol & Co of Glasgow was appointed contractor.
The new bridge took just 5 years to build, thanks in most part to special pontoon equipment with hydraulic legs which were designed by William Arrol. Various arrangements of these hydraulic pontoons were used to sink and construct the brick and concrete foundation columns, to erect the wrought iron piers, to move the old girders into position for the new bridge, and to erect the new navigation spans. The completed bridge is 10711ft in length, 8396ft of which is in a straight line running virtually north / south across the Tay until it curves eastwards towards Dundee. There are 85 piers; 1-28 forming the south approach, 28-41 the ‘navigation spans’ and 41-85 the north approach. The new Tay Bridge was opened to traffic, without ceremony on 20th June 1887.It still stands as testament to what good engineering was used in it's build.
