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
Most cities were mostly built by improvisation In Architecture Without Architects, Bernard Rudofsky documented the ways in which most cities were mostly built by improvisation, following no consistent formal design. Building was added to building, street to street, their forms adapting to different site conditions in the process of extension. Rudofsky thought that this hidden order is how most settlements of poor people develop and that the work of improvising street order attaches people to their communities, whereas 'renewal' projects, which may provide a cleaner street, pretty houses, and large shops, give the inhabitants no way to mark their presence on the space. Richard Sennett, The Craftsman I am hereNon-architects urbanism