Design blunders in vanity project
THE 1.7-mile Queensferry Crossing, which opened in 2017 at a cost of some £1.3billion, was the longest three-tower, cable-stayed bridge in the world and by far the largest to feature cables which cross mid-span.
Exposed to extreme weather with open sea conditions, the vast increase in elaborate cabling magnified many times the risk of icing which had dogged the 1964 Forth Road Bridge.
As it was partly a vanity project, the advice of international engineers that a tunnel would be cheaper, impervious to weather and make better use of the existing road network was rejected.
Holyrood now has the problem that there’s currently no reliable method to deal with ice build-up on such an ostentatious, cable-stay bridge. It’s hard to see how this catastrophe can be blamed on Westminster.
Dr John Cameron, St andrews, Fife. WITH the supposed ‘all-weather’ Queensferry Crossing being closed by very modest snowfalls, you wonder what predictions for weather conditions the designers were relying on.
You would expect any designer with the slightest knowledge of Scotland to allow for a winter at least as bad as that of 2010-2011, when the country ground to a halt for most of December.
Indeed, given a life expectancy of more than 100 years for the bridge, they should have allowed for significantly worse than that.
Is it possible the designers, or more likely their paymasters in the Scottish
Government, were relying on the predictions of climate scientists?
For example, in 2000 Dr David Viner of the University of East Anglia was quoted as saying within a few years winter snowfall would become a ‘very rare and exciting event’. Unfortunately for the motorists of Fife, Dundee and beyond, not rare enough.
otto InglIS, edinburgh. THE very latest safety feature has just been announced for the flagship Queensferry Crossing: someone is to walk around with a pair of binoculars inspecting the high-rise cables! What a shambles. They could have at least given them a thermometer to hold in the other hand, so they had an indication of when ice is likely to form.
P Robertson, burntisland, Fife. ALL they had to do when building this bridge was to incorporate a low-voltage heating system in the cables, a bit like the heated rear windscreen of a car. Problem solved. Simple.
Karl Edwards, argyll.