The world’s largest 3D-printed footbridge is 15.25 metres long, 3.8 metres wide and 1.2 metres tall. It was created in China.
It took Chinese construction company SMCC and filament manufacturer 3D Polymaker 30 days to bring this project to life. They used an XXL 3D printer able to print objects up to 24 metres in length, 4 metres in width and 1.5 metres in height. They selected ASA (acrylonitrile styrene acrylate), a plastic that is particularly resistant to heat, water and harsh weather conditions, which was reinforced by the inclusion of 12.5% of fibreglass for the occasion.
The strength of the bridge – which alone weighs 5,800 kgs, making it the world’s heaviest 3D-printed plastic object – was tested by Chen Xiaoming, an engineer at SMCC, who stated that: “The bridge can bear a load of 250 kg per square metre, which means that it can withstand the weight of at least four adults per square metre.
The last step in its construction will involve laying a transparent floor offering a view of all of the structure’s printed layers. The bridge will be placed over a waterway in a park in Taopu Smart City, an innovation centre in Shanghai, in 2020.
It is expected to last for over 30 years, and any damaged part could be quickly replaced using the 3D printing process.
However, this feat of engineering is not the first of its kind: a 3D-printed bridge was built in Spain, but the material used to make it was concrete reinforced with polypropylene fibres. Some bridges have been 3D printed using steel filaments, and the College of Architecture and Urban Planning of Shanghai University unveiled its first two plastic 3D-printed bridges in 2017. Unlike this footbridge, the 2 bridges measuring 4 and 11 metres respectively were not intended to bear the weight of pedestrians. Quite the oversight!