Institution President, Ian Firth, discusses the engineering behind structures completed in 1897
This is the first in a series of monthly blogs celebrating structures whose completion anniversary falls this year. We start by thinking about 1897 – 120 years ago – and consider four notable structures completed that year; two bridges, a Ferris wheel and a major building. The fact that all are still standing and serving their original purpose is a testament to the skill of the engineers responsible for their design and upkeep. I will look at 110-year-old structures in February and finish with 10-year-old structures in December.
I have just selected a few in each case, but I hope that this blog might stir discussion. If anyone out there has insights or information to add about these, or any other significant anniversary structures along the way, then please comment below!
1 Findhorn Viaduct, Scotland
(Image source Wikimedia Commons, by James Hearton)
This beautiful curved viaduct carries the Perth to Inverness railway line over the valley of the river Findhorn near the village of Tomatin, about 14 miles south of Inverness. It was designed by Sir John Fowler (famous as the designer of the Forth Railway Bridge north of Edinburgh) and Murdoch Paterson.
It was built between 1894 and 1897, is just over 400m long, and consists of nine spans of lattice steel structure supported on stone columns. Sir John Fowler used a similar design here as he did for the approach viaducts of the Forth Railway Bridge, with the double Warren truss arrangement for the girder (meaning the X-shape pattern of bracing when viewed side on) and the tapering stone columns being common to both structures.
I like the elegant simplicity of this structure. The curved alignment, the strong rhythm and reassuring solidity of the columns, and the delicate lightness of the girder create a pleasing composition which suits the setting well. Thanks to the quality of the engineering design and construction It has lasted 120 years, no doubt with the help of some timely preventative maintenance, and with care should last a whole lot longer.
2 Giant Ferris Wheel, Vienna
(Image source Wikimedia Commons, by Jorge Royan)
This famous Ferris wheel was also completed in 1897 and still turns today. Starring in numerous films, including The Third Man
and the James Bond film, The Living Daylights
, it is a popular tourist attraction in the Prater amusement park, Vienna.
The design is by the British engineer, Walter Basset, who was also responsible for several other big Ferris wheel designs. These attractions were extremely popular at the end of the 19th century and the beginning of the 20th, and seem to be enjoying a renaissance in our own time.
The Vienna giant wheel, or Reisenrad, is 65m tall, and was the world's largest from 1920 (other taller ones having been demolished) until 1985. The current largest at 168m tall is the Vegas High Roller, recently completed in Las Vegas, which was a winner in The Structural Awards in 2015. The London Eye, completed in 1999, is 135m tall and was a Structural Award winner in 2001.
The Vienna Reisenrad was built to celebrate the golden jubilee of Emperor Franz Josef 1. It nearly didn't survive because a permit for its demolition was issued in 1916, but funds were scarce at the time (there was a war on!) and the demolition was put on hold. It originally had 30 gondolas, but was severely damaged in World War 2, and when re-constructed only 15 were replaced. The rim of the wheel is suspended from the hub by steel cables which act as the spokes in tension, and the wheel is driven by a cable which passes round the circumference and down to the drive mechanism under the base. Sadly, Walter Basset's Ferris wheel business was not a commercial success and he died in 1907, almost bankrupt.
3 Whirlpool Rapids Bridge, Niagara Falls
(Image source: Wikimedia Commons, by Balcer)
Completed in 1897, this steel arch bridge was designed by Leffert L Buck, who is also famous for other major bridge works, including the Williamsburg Bridge in New York, which has a main span of 488m.
Buck had previously been responsible for the reconstruction of Roebling's famous railway suspension bridge over the Niagara Gorge, replacing all the components apart from the original suspension cables, without closing the bridge to railway traffic.
At this site there was also a suspension bridge, which could no longer carry the increasing rail traffic loading. Once again, Buck conceived a design which could be constructed on the same alignment without closing the railway line. Starting in April 1896, the steel arches were built out from both sides of the gorge, working towards the centre, immediately underneath the old bridge. The old bridge girder, still suspended from the suspension cables, was built into the new arch structure, so that on completion of the arch both the old and the new structures acted together. Then the towers and cables of the old suspension bridge were removed, as well as any other components that were not needed in the new structure. Thus, history records that the new 245m span arch bridge was completed without any interruption of the railway - a significant achievement indeed!
Buck was awarded a Medal of Excellence by the American Society of Civil Engineering (ASCE) and in 1901 he received the Telford Premium Award from the Institution of Civil Engineers.
4 Thomas Jefferson Building, Washington
(Image source: Wikimedia Commons, by Carol M Highsmith)
While Leffert L Buck's arch bridge was being constructed over the Niagara Gorge, this building was at last nearing completion in Washington after long and frustrating delays. Originally known as the Library of Congress Building, the design was the winner in an architectural competition in 1873.
Architects Paul J Pelz and John L Smithmeyer won the competition, (the record doesn't mention the structural engineers!) but due to disagreements and/or procrastination in Congress, construction didn't start until 1886. Then, in 1888, Smithmeyer was dismissed, leaving Pelz in charge - until he was also dismissed in 1892.
Pelz was replaced by Edward Pearce Casey, the son of Brigadier General Thomas Lincoln Casey, Chief of the U.S. Army Corps of Engineers, who was in charge of construction. (Engineers to the rescue?!) So finally the building was opened In 1897, with the ornate interior decoration being completed the following year.
The central section of this enormous building expresses a kind of triumphant nationalism which has been compared to the Palais Garnier in Paris, and the copper dome, which was originally gilded, was criticised for apparently competing with the national Capitol Building.
Incidentally, among many other achievements, Brigadier General Thomas Casey was also responsible for the re-design and completion of the Washington Monument after problems were found with the original design. He was quite a guy – worth looking him up in Wikipedia
Let's hear it for the engineers!