Would you walk across a 3D-printed bridge? For folks in Amsterdam, the question now poses a real opportunity. Imperial College of London has spent the last four years working with Dutch company MX3D to develop a 3D-printed steel bridge that would serve as a “living laboratory.” Through a network of built-in sensors, researchers at Imperial College will be able to monitor the bridge’s performance as pedestrians use it daily. The bridge was unveiled this month by Queen Máxima of the Netherlands.
At 12 meters long, the stainless steel pedestrian bridge stretches across Amsterdam’s old and beloved Oudezijds Achterburgwal canal in the Red Light District. MX3D first kicked off its design in 2017, after which the company quickly won the European STARTS prize, a 2018 Dutch Design Award, and the 3D Pioneers Challenge for the bridge’s innovative design. Its construction took six months and 4.9 tons of steel. In 2019, MX3D and Imperial College tested the bridge under a 20-ton load at the University of Twente, and earlier this year, the bridge was finally installed.
So why 3D-print a bridge instead of using older construction methods? MX3D said it wishes to see how the public interacts with 3D infrastructure. The bridge’s sensors (instrumented by Autodesk, The Adam Turing Institute, and the Amsterdam Institute for Advanced Metropolitan Studies) collect data related to strain, displacement, and vibration. They also “measure environmental factors such as air quality and temperature, enabling engineers to measure the bridge’s health in real time and monitor how it changes over its lifespan.” Researchers from Imperial College will then input that sensor data into the bridge’s “digital twin,” a dynamic computer model that will subsequently provide insights on how to design and construct similar 3D printed metal structures.
Imperial College reports that 3D-printed stainless steel was tested throughout conception via destructive tensile testing, which provides insight into the yield strength and ductility of a metallic material. Imperial’s Department of Materials conducted tests on both smooth and “as-built” materials to understand the metal’s load-bearing capacity. The bridge’s futuristic geometry was created using silicone casting and laser scanning.
Depending on the success of the bridge, MX3D may develop future 3D-printed infrastructure. Various companies are already working on scaling 3D-printed housing, while others are researching the time and cost advantages of using 3D printing technology over manual construction labor.
MIT and Amsterdam Partner on Autonomous ‘Roboats’
While most cities are revving up to get self-driving cars on the roads, Amsterdam is more interested in autonomous boats. The Dutch city is about one-quarter water thanks to its massive network of canals, and it has visions of robotic boats cruising those waterways.