Her Majesty Queen Máxima of the Netherlands has unveiled the world’s first 3D-printed steel structure, a ‘living laboratory’ pedestrian bridge over the Oudezijds Achterburgwal canal in Amsterdam’s red light district.
More than four years in the making, the 12-metre-long bridge was designed and built by a team led by Dutch company MX3D, with assistance from researchers at Imperial College London (ICL).
‘A 3D-printed metal structure large and strong enough to handle pedestrian traffic has never been constructed before,’ said Leroy Gardner, a professor in the Department of Civil and Environmental Engineering at Imperial. ‘We have tested and simulated the structure and its components throughout the printing process and upon its completion, and it’s fantastic to see it finally open to the public.’
Installed within the bridge is a vast network of sensors that the ICL researchers will use to measure, monitor and analyse how the structure handles pedestrian traffic.The data, which will be made available to other researchers worldwide, will enable engineers to measure the bridge’s ‘health’ in real time, monitor how it changes over time and understand how the public interacts with 3D-printed infrastructure. They will be used to refine a ‘digital twin’ of the bridge that will more and more accurately mimic the physical bridge as more sensor data come in.The physical bridge’s performance and behaviour will be tested against the twin in order to help answer questions about the long-term behaviour of 3D-printed steel, as well as its use in real world settings and in future novel construction projects.
Because the team was breaking new ground building a public structure from 3D-printed steel, it conducted intensive physical testing and computer simulation to ensure that the bridge would be safe to use. This involved testing destructive forces on printed elements, advanced digital twin computer simulations and non-destructive real-world testing.
‘We look forward to continuing this work as the project transitions from underpinning research to investigating the long-term behaviour of metal printed structures,’ said ICL’s Craig Buchanan. ‘Research into this new technology for the construction industry has huge potential for the future, in terms of aesthetics and highly optimised and efficient design, with reduced material usage. It has been fascinating and we are delighted that the structure is now ready to be used.’
‘3D printing presents tremendous opportunities to the construction industry, enabling far greater freedom in terms of material properties and shapes,’ said Professor Gardner.‘This freedom also brings a range of challenges and will require structural engineers to think in new ways.’
‘3D printing is poised to become a major technology in engineering, and we need to develop appropriate approaches for testing and monitoring to realise its full potential, said Professor Mark Girolami of the Alan Turing Institute, which provided some of the funding for the project and will be involved in the analysis of the sensor data. ‘When we couple 3D printing with digital twin technology, we can then accelerate the infrastructure design process, ensuring that we design optimal and efficient structures with respect to environmental impact, architectural freedom and manufacturing costs.’