By Luke Carothers

The Oudezijds Achterburgwal is one of the oldest canals in the world.  Built in Medieval times, the canal once formed the Eastern border of Amsterdam, but it now runs directly through the city’s famous Red Light District.  The Oudezijds Achterburgwal is being updated for modern times with several new projects, including the construction of the world’s first stainless steel 3D printed bridge.  

The pedestrian bridge crossing the Oudezijds Achterburgwal was built by Dutch startup MX3D who collaborated with Autodesk through the entirety of the project.  The 40-foot long bridge, which is made of more than 6,000 kgs of stainless steel, was 3D printed by a team of four robots.  In addition, the bridge is breaking ground in terms of its ability to self-monitor, meaning that the bridge is outfitted with a sensor network that captures data on structural impacts of strain, rotations, and vibrations as well as air quality and temperature.  These features make the bridge a “living lab.”    

This impetus for this project came in 2015 when Autodesk and MX3D began working together to create a proof-of-concept project in Amsterdam.  According to Alex Tessier, Director of Simulation, Optimization, & Systems at Autodesk, the idea was to, “showcase all facets of conventional manufacturing technologies while pushing the envelope of art and design.”  This started with the dream goal of printing a bridge in place and exploring the accompanying possibilities with it.  The team explored processes such as exploring the use of robotics to create 3D structures by building up welds from mounted MIG welders.  

These early stages of the project were not only focused on questions about process, but also on how the materials would perform on a larger scale.  Furthermore, because the bridge would be used by pedestrians, the team wanted to find a way for the bridge to “give back” to the community.  

To answer these questions and achieve this goal, Autodesk began creating a prototype and testbed for the bridge in 2017 at their Autodesk Technology Center at Pier 9 in San Francisco.  This early testing involved designing and building their own sensors and software to monitor the bridge.  The goal was to explore use cases for structural health monitoring, digital twins, intelligent sensors, cloud and edge processing, automated analysis of data in real time, and the role that smart infrastructure could play in smart cities of the future.  In completing these stages of research, Autodesk collaborated with the Joris Laarman Lab, The Alan Turing Institute, Arup, the University of Twente, and others.

The final result of these efforts is a bridge that is embedded with a system of sensors that monitor its environment, performance, and use.  This network of sensors provides data that is then processed in real time; according to Alex Tessier, this creates “data streams that can [be woven] together” to form a digital twin of the bridge.  Sensors are currently measuring forces such as load distribution, tilt, strain, acceleration, and temperature.  There are also environmental sensors that monitor the local microclimate around the bridge.  Tessier believes that this data will “help us understand how things are used and how to make them better, safer, and more useful.”  Additionally, in the coming months Autodesk is looking to install advanced computer vision that will allow the bridge to anonymously monitor pedestrian loads.  This advanced computer vision has already been developed at the Autodesk Technology Center at Pier 9, and Tessier is confident it will soon be installed in Amsterdam.

With all systems in place, the MX3D Bridge in Amsterdam will, by fusing data from all the sensors, be able to learn how the bridge responds to many different conditions and factors over time.  This project is perfectly timed at a moment when the world is responding to the growing problem of aging infrastructure.  Tessier believes it is imperative that engineers’ creations “participate in the data economy and automate the findings and democratize them so that society can have access to this large library of learning.”  This helps engineers and contractors to be more sustainable and use less material.


Luke Carothers is the Editor for Civil + Structural Engineer Media. If you want us to cover your project or want to feature your own article, he can be reached at lcarothers@zweiggroup.com.  

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