Under the Microscope: Most of us don't think about the built environment often but it nevertheless exerts a powerful effect on us, writes William Reville.
I always like to see the Four Courts or Leinster House on TV because I find the images of the buildings so satisfying. I think the average person would like to be an architect, and sometimes daydreams of magnificent buildings they would design. I do, but I wouldn't make much of an architect as I am not good at visualising how spaces interact in three dimensions.
There is a concept in architecture called "honest design", in which all the features serve the function of the structure. Probably the best-known honest design is in the Eiffel Tower, designed and built by Alexandre Gustave Eiffel (1832-1923). While Eiffel completed his work with consummate efficiency, Sydney Opera House entailed such massive over-runs of time and expense in pursuit of honest design as to demonstrate that, sometimes, common sense calls irresistibly for compromise.
The Eiffel Tower was built for the Paris Exhibition of 1889. Standing 300 metres high, it was the tallest man-made structure of its time. The only practical use of the Eiffel Tower is to provide splendid views over Paris, and its real purpose was to demonstrate that France was a leader in the technical world.
The Eiffel Tower was always massively popular with the public, but not with the artistic elite at the start. The tower could be seen from anywhere in Paris. The writer Guy de Maupassant detested it so much that he had lunch in the tower restaurant as often as possible because it was only in the tower itself that you did not have to look at it.
Two million people visited the tower in its first year and it became ever more popular as the years went by. Looking at the tower became just as important as looking from the tower. Slowly the Eiffel Tower became the pre-eminent symbol of Paris and of France. It was painted by important artists and praised by poets and novelists. Hitler promised to destroy it, but resistance fighters flew the tricolour from the tower while American tanks were still engaging Panzer tanks in the streets below. Today tourists still flock to the tower, and terrorists threaten to bomb it. The tower has transcended its physicality to become a great human symbol.
Viewed from a distance, one is struck by the graceful shape of the Eiffel Tower. Moving closer, you begin to resolve the detailed structure, the massive base and the countless rivets that hold the whole thing together. Eiffel produced more than 14,000 square feet of drawings, detailing the 15,000 structural parts and the 2.5 million rivet holes. The erection of this 8,000-tonne jigsaw-puzzle by only 250 workers was a feat of genius in itself. The tower was finished in two years, two months and five days, without a single worker being involved in an accident. Eiffel estimated the cost at $1.5 million but built it for 5 per cent less.
The structure of the tower is simple. It sits on four massive buttresses each inclined inwards at an angle of 44 degrees and tied together and prevented from falling by the first horizontal platform at 180 feet above ground. Every tower must stand up to wind. One solution is to make the tower so massive that it always prevails against wind force. The other way is to make the surface of the tower so minimal that the wind cannot get an effective grip on it. Eiffel relied on the second method. His tower is a delicate lacework of iron on which the wind can command little grip. The design of the Eiffel Tower (below) is almost completely honest, with the exception of four arches under the first platform that have no structural purpose. Eiffel thought that the public might dislike the appearance of the inclined buttresses supported by the horizontal square first platform and he made the decorative addition so the casual observer would think that the lower level of the tower was supported by familiar arches.
The Sydney Opera House stands over the harbour like a great ship with its sail-like concrete shells rising from a terraced platform. In 1957 the Danish architect Jorn Utzon won an international design competition with a series of freehand sketches. Nine years behind schedule and massively over original budgets, the opera house opened in 1973 following a protracted pursuit of honest design.
Early in the design project it was decided that, although the shape of the shells derived mainly from visual considerations, they would have to stand against wind and gravity without the help of additional structural framing from underneath. Many millions of dollars were spent on years of computing and engineering to design the hugely complex, pre-stressed concrete roof to make this possible. A far simpler and less expensive system of hidden steel trusses could have supported the shells of the opera house roof.
I don't think Eiffel would have approved. He certainly had no problem with bracing the Statue of Liberty with an internal iron skeleton against the rigours of New York harbour.
William Reville is associate professor of biochemistry and director of microscopy at UCC