How does scaffolding work?
These everyday structures are vital in the field of construction
You might notice them being built around an old building on your street almost overnight, but scaffolding can also used to support structures such as half-pipes, ski ramps and concert stages. Scaffolding is even used to maintain large boats and iconic landmarks such as London’s Elizabeth Tower.
The teams of scaffolders need a strong head for heights and impeccable balance. It’s no easy task to lift, move and place thousands of steel tubes, weighing approximately 4.5 kilograms per metre, and there is a lot at stake if things go wrong. Though it can look a little precarious to see construction workers on top of dizzyingly tall skyscrapers, feel assured that scaffolding is assembled to a very high standard and is regulated by authorities. However, this isn’t a new technology we’ve developed in recent years. The paleolithic cave paintings at Lascaux in southwest France are accompanied with markings that suggest a scaffold system was built to paint the ceiling around 17,000 years ago.
Today, a scaffolding structure primarily consists of tubes, couplers and boards. Tubes are generally made from steel or aluminium, with a standardised diameter of 48.3 millimetres and are available in different lengths. The couplers are used to hold the tubes together in their familiar grid pattern, of which there are three basic varieties. Finally, the boards allow construction workers to move around on the scaffolding and tend to be made from seasoned wood.
Hong Kong’s iconic skyline is dotted with skyscrapers, and surrounding many of them is a traditional scaffold structure crafted with bamboo. Instead of steel or aluminium, parts of Asia have utilised this flexible, strong and lightweight wood for centuries. The plant grows in abundance, taking approximately four years to grow to the correct height before being chopped down, dried for two months, and cut into seven-metre tubes to use in construction. It might look precarious to see the wood lashed together with nylon strips, but the design of a grid pattern formed by 75-centimetre squares offers so much stability that skyscrapers up to 70 stories tall can be built using this ancient craft.
This article was originally published in How It Works issue 108, written by Charlie Evans
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