Routine design When we think of bridges, it is the dramatic and monumental long spans that come to mind first, especially the lithe suspension bridges such as the Golden Gate and the pure geometric arches such as Sydney Harbour. But the majority of bridges are not such spectacular structures. Most of them are ordinary overpasses, with spans of 30 or 40 feet, carrying roadways or rails across other thoroughfares or over small streams. You see such bridges by the dozen on any drive down the Interstate. They may be lacking in glamour, but they are more representative of a bridge builder's art. The engineering and construction of girder bridges are pretty routine these days, but the bridges are not quite standard items you order from a catalogue. The girders, whether of steel or concrete, are custom-build for each bridge, then trucked to the site and hoisted into place with a crane. The designer still has scope for variation and creativity, and it shows out on the highways: some overpasses are prettier than others. Brian Hayes, Infrastructure: A Guide to the Industrial Landscape engineeringdesignautomationroutine
Invisible substance We wanted wood, not only in many visible places, but also in the roof trusses of the homeroom buildings, where they are invisible. Fujita wanted to replace the invisible trusses with steel trusses. They could not understand the idea that it was the actual substance — even though not visible — which would control the feeling of the thing. Christopher Alexander, The Battle for the Life and Beauty of the Earth All the way throughFinished on the inside material