What the first 3D printed steel bridge looks like
On July 15, 2021, a 12-meter steel footbridge opened in Amsterdam. It would seem nothing out of the ordinary. You won’t surprise anyone with bridges in Amsterdam. But unlike other steel bridges around the world, this one was 3D printed.
The printed bridge over the Oudezijds Achterburgwal canal. It is located in the Red Light District in the heart of Amsterdam.
Who and how unsealed the bridge
This first bridge of its kind is made using stainless steel rods. They are welded into a single structure by a robotic system in the workshop of the Dutch technology company MX3D in collaboration with the engineering firm Arup.
The weight of the structure is 6 tons, and it reaches 12 m in length.
The bridge was printed by four robots by welding layers of stainless steel wire, taking 4.5 tons of steel and six months to make a span of 12 meters. Then the bank supports and decorative elements were made.
After combining robotic arms with welding machines for a machine capable of printing furniture, the idea for such an unusual bridge came from Joris Laarman (founder of the Dutch studio Joris Laarman Lab).
The structure was installed for two years as a replacement for the conventional bridge, which at that time will be under reconstruction.
The bridge was first unveiled at Dutch Design Week 2018 in Eindhoven, where the project won the Dutch Design Award and the Audience Award. After that, the finished bridge lay in the warehouse for another three years: first, waiting for the reconstruction of the canal, then due to the coronavirus pandemic and lockdown.
What else is interesting in the printed bridge
The curved S-shape of the bridge and the perforated lattice balustrades were designed using parametric modeling software.
The development team claims this 3D printing technology could lead to more efficient designs that use less material.
In addition to performing the main function, that is, the ability to cross the channel, the bridge is a living laboratory with a whole network of various sensors. They collect real-time data on bridge performance.
Every time someone walks runs or rides a bicycle across the bridge, sensors read information. It is then used to monitor the structure and condition of the bridge. A sensor system to measure the stress, displacement, and vibration of the steel structure. As well as air quality and ambient temperature.
All this data is used to create a digital copy of the bridge, which will simulate a real bridge. This will allow you to predict the future behavior of the bridge and inform the developers of the need for maintenance at the earliest opportunity.
But that’s not all. Collecting the data will enable engineers to understand how 3D-printed steel structures can be used for larger, more complex construction projects.
What the engineers say
“A 3D printed metal structure that’s big and strong enough to handle pedestrian traffic has never been built before. We tested and modeled the structure and its components throughout the printing process and beyond, and it is fantastic that it is finally open to the public, ”says Leroy Gardner, a civil engineer at Imperial College London.
“3D printing offers tremendous opportunities for the construction industry, providing much more freedom in the choice of material and shape properties,” added Gardner. “This freedom also presents a host of challenges and will require civil engineers to think in new ways.”
Tim Guertiens, Co-founder at MX3D, said the project’s success has important implications for the future of architecture. “If you want to have a nicely designed bridge or an aesthetic bridge, suddenly printing it is a good option,” he said. “Because it’s not just about making things cheaper and more efficient for us, it’s about giving architects and designers a new tool — a very cool new tool — with which they can rethink the design of their architecture and their projects.”