World’s first 3D-printed concrete cycle bridge opens in the Netherlands

Last Tuesday, October 17^th, the Netherlands inaugurated the world’s first 3D-printed concrete bridge, which is primarily meant to be used by cyclists. The bridge, which crosses a canalized river in the southeastern town of Gemert, is made of 800 layers of reinforced, pre-stressed concrete with a steel cable running through it to handle tensile stress. Constructed in Eindhoven by the Technical University of Eindhoven and the Dutch construction company BAM, it is 8 meters long by 3.5 meters wide and it took around three months to put together, while its life cycle is estimated at 30 years at least. “The bridge is not very big, but it was rolled out by a printer, which makes it unique,” Theo Salet, from the Eindhoven University of Technology. The new bridge is part of the Noord-Om project, a new section of ring road around the village of Gemert linking the existing routes N605 and N272, and hundreds of cyclists are expected to ride over it every day.

The structure

The concrete bridge was 3D printed in several parts (eight one-meter sections) using a special concrete mortar, and was then put together on-site. The eight sections were placed between two bridge heads and secured using heavy-duty cables. The first-of-its-kind structure must meet strict safety requirements, so it was tested for safety to bear loads of up to two tonnes.

Environment-friendly construction

Another positive outcome of this technique is that much less concrete is needed to 3D print such structures instead of building them in traditional ways, because the printer deposits the concrete only where it is needed. This means that fewer scarce resources are needed and significantly less waste is produced, leading to a reduction of CO₂ emissions. “We are looking to the future,” said Marinus Schimmel, head of BAM, adding that the company is constantly “searching for a newer, smarter approach to addressing infrastructure issues and making a significant contribution to improving the mobility and sustainability of our society.”

Other 3D-printed bridges

The bridge in Gemert however, is not the first 3D-printed concrete bridge that was unveiled, as thecity of Alcobendas in Spain actually inaugurated its own 3D printed concrete pedestrian bridge in 2016. The Spanish structure has a total length of 12 meters and a width of 1.75 meters and was printed in micro-reinforced concrete.

MX3D, another Dutch start-up, has also started the 3D-printing of bridges  from stainless steel. The company has already constructed the 1/3 of such a bridge, which is expected to be ready by March 2018 and placed over a canal in Amsterdam before next June. 

The Gemert 3D printed bridge during construction

 Photo source: 3Ders.org