China has unveiled its first 3D-printed retractable bridge. Located in Shanghai’s Wisdom Bay Innovation Park, the proverbial Mecca for 3D technology firms, the near-10-metre bridge is controlled via Bluetooth and retracts or unfurls in around a minute.
The massive feat is viewed by those close to the project as a significant step in the large-scale adoption of 3D printing and retractable architecture.
Built over a shallow reflection pool, the bridge measures around 9.5 metres long, 1.1 metres high and 1.5 metres wide. The structure is relatively lightweight for its size, tipping the scales at 850kg, and can support the weight of 20 adults. Should the bridge exceeds its maximum load-bearing capabilities, the built-in gravity sensitive warning system is automatically activated.
The reason the bridge can support the weight is because of its unique construction. It is constructed of 36 3D-printed triangular panels, divided over nine segments. Each panel features a unique spiral pattern and is made from environmentally friendly composite carbonate polyester.
Triangles have many properties, one of which is their incredible strength and it’s for this reason that engineers and architects often use them in construction. Printing nearly a tonne’s worth took little over three days, according to the digital media outlet, 3D Printing Industry.
Wisdom Bay is home to a multitude of 3D printing, Virtual Reality (VR), Augmented Reality (AR), and robotics firms and startups – more than 360 international companies. 3D Printing Industry reports that the Bay is supposedly home to the only museum dedicated to all things 3D printed.
In 2019, Wisdom Bay played host to another feat of engineering. The University of Tsinghua built, at that time, the largest 3D-printed bridge in the world. This time printed from concrete, the bridge was almost 27 metres long, 3.6 metres wide and took 450 hours to print.
The university also built a 30 square metre, earthquake-resistant bookstore in Wisdom Bay Park, from a fibre concrete mixture, which took nearly three weeks to construct.
Several other 3D-printed structures have surfaced around Shanghai. A 15.25-metre-long pedestrian bridge was erected by the Shanghai Mechanized Construction Co. and Polymaker, a 3D printing filament producer. The two firms engineered the feat to demonstrate environmentally friendly construction and showcase smart technologies like 3D printing.
Similarly created footpaths, bridges and walkways are being constructed in cities around the world. For example, Rotterdam is home to the earliest example of a 3D bridge, printed from fibre-reinforced thermoplastics.