QUEENSFERRY BRIDGE

The new Queensfery Bridge opened today. It joins the south side of the Firth of Forth (Edinburgh side) to the  north side providing a trunck route to the north-east of Scotland.

BBC photo

BBC photo

Iain showed me this article which is about an Edinburgh man who came up with a design 200 years ago.  The bridge is uncannily similar however it was never built.

Times Article August 30, 2017

UNCANNY SIMILARITY TO PLANS FROM 1818

 
It has been described as a “feat of modern engineering” but the Queesferry Crossing was first imagined by a little-known engineer whose 19th century plans have been found ion a vault at Edinburgh University (Gurpreet Narwn writes).
The designs drawn up by James Anderson in 1818 look remarkably similar to the crossing, which opens to the public today after almost ten years of planning and six years of construction.
Mr Anderson, the son of a textile worker in Edinburgh, envisaged “A Gridge of Chains proposed to be thrown over the Frith [sic] of Forth.”

The blueprints were discovered in the university’s archive by Bruce Bittings, a researcher.

The plans for a roadway linking North and South Queensferry were proposed 72 years before the completion of Sir John Fowler and Sir Benjamin Baker’s Forth Bridge, which still carries the railways across the famous waterway.

Anderson’s design and the new Queensferry Crossing are both suspension road bridges, with their supports extending as straight lines from the towers.  Anderson’s scheme has the roadway supported by chain cables, forged from iron bars.

He drew inspiration from Thomas Telford’s bridge across the Menai Strait in north Wales and proudly suggested his timber-decked crossing would “facilitate the communication between the southern and northern divisions of Scotland.”

The project would have cost between £200,00 at the time, which equates to about £840 million today - substantially cheaper than the £1.4 billion Queensferry Crossing.

Whilst his ambitious plans were beyond the capabilities of early 19th century bridge engineers, he has been credited for his visionary design.

A civil engineering biographical dictionary said he “deserves credit for visualising what the suspension=bridge principle would eventually achieve, and for incorporating in his designs some provision against oscillation of the deck.”

Anderson was elected a Fellow of the Royal Society of Edinburgh in 1836 and died at his home in the city in 1861.