Longest 3D Printed Pedestrian Bridge Under Construction

The Netherlands opened the world’s first 3D printed concrete bridge in 2017. Now, the nation has its eyes set on another landmark achievement using additive manufacturing. Construction has now started on what will be the world’s longest 3D printed bridge.

The current longest 3D printed bridge in the world opened in 2019 in Shanghai, China, and stands at 86 feet long. This new project in Nijmegen, Netherlands, will be more than 95 feet long once completed. In addition to breaking records, this bridge represents a shift in both 3D printing and construction.

Pushing Boundaries

This project, appropriately named “The Bridge Project,” is part of a broader movement in the Netherlands, with Nijmegen called the Green Capital of Europe in 2018. The nation has a reputation for being one of the most eco-friendly in the world, and 3D printing in construction plays into that. The Netherlands is home to the first 3D printed concrete bridge, the first 3D printed steel bridge, and will soon be home to the longest.

The project is being co-commissioned by the Dutch public works department, Rijkswaterstaat, and will be printed in Eindhoven at the BAM and Weber Beamix 3D printing facility. The design itself was devised by Michiel van der Kley and modeled parametrically by Summum Engineering. Weber Beamix is the mortar subsidiary of the large and very old Saint-Gobain, which focuses on construction and materials. BAM is the largest construction company in the Netherlands.

Like its 2017 predecessor, the Bridge Project is a pedestrian and cyclist bridge, not one for larger vehicles. Still, the 2017 bridge could theoretically hold the weight of 40 trucks, so this one will likely boast similar strength. The structure isn’t intended to support motor traffic, but that doesn’t mean it can’t.

The Bridge Project aims to disrupt the current construction process. On top of providing an eco-friendlier way to build, 3D printing could enable more natural designs that blend into their environments. New structures could become a part of the surrounding nature instead of an obstacle that cuts through it.

The team behind the Bridge Project hopes to bring this design philosophy and construction method to more areas. If all goes according to plan, this project will lead to more 3D printed bridges, buildings, and other structures in the future.

Advantages of 3D Printing in Construction

The Bridge Project is the latest example of the rising trend of additive construction. While this practice is still in its infancy, it holds a lot of potential. As mentioned before, 3D printing can make more innovative, seamless designs, but it has other advantages, too.

3D printing can raise structures in a fraction of the time traditional methods require. The bridge in Shanghai, for example, took just 450 hours to complete. Since printers can produce entire structures on-site, they also reduce the number of vehicles and workers needed, saving money. It’s worth noting that, in the case of the Bridge Project and many others, components are often 3D printed off-site and then assembled in their final location.

In many traditional projects, construction companies have to assemble them in pieces, then put them together. In some cases, additive manufacturing enables teams to create a structure as a single, cohesive piece—though other elements, such as a roof, windows, plumbing and electricity are still integrated separately. As a result, they can improve structural integrity and reduce the risk of errors.

Since 3D printing is faster and requires less machinery, it’s more sustainable. Any equipment that teams do use won’t run for as long, reducing energy-related emissions.

Challenges in Large-Scale 3D Printing

Despite these benefits, some challenges remain with additive construction. Since this process is so new, the necessary expertise and machinery can be difficult or expensive to obtain. There aren’t many companies that specialize in 3D printing on this scale yet. This number is growing steadily, however, with startups that include Mighty Buildings and ICON, as well as businesses and projects from larger corporate entities, such as COBOD. Then, of course, there are BAM and Weber Beamix behind the Bridge Project.

Finding suitable printing materials can be complicated, too. Companies need to verify the composition and quality of raw materials to ensure they meet industry standards for any construction project. With 3D printing, they must meet even higher requirements, as they have to print well, dry quickly, and bond easily.

As more companies embrace these methods and technology advances, the industry will overcome these roadblocks. New safety and quality standards will emerge, printers will become more affordable, and more people will become familiar with the process. Since experts predict the additive construction market will grow by 147.79% a year by 2023, that may not take long.

Large-Scale Projects Could Push 3D Printing Forward

As the construction industry looks for ways to become more sustainable and efficient, 3D printing becomes more valuable. Similarly, construction projects like this bridge in the Netherlands bring new attention to 3D printing. The technology will grow and advance faster as a result. The Bridge Project shows how far additive construction has come in its relatively short history. Before long, it could become a standard practice in the construction industry.