Seven years ago, ACCIONA began researching into the potential of additive manufacturing (3D printing) in construction, one of its core businesses. The research involved the development of the 3D printer and manufacturing technology in collaboration with Italian company D-Shape; selection of materials in collaboration with universities; and architectural and engineering design.
Luis Clemente, COO-3D Printing, ACCIONA, says: “The first prototype we developed was a 2x2x2m printer with which we started trials to discover what we could achieve with the printer. We fine-tuned the technology for commercial use and demonstrated it in the construction of the first concrete 3D printed footbridge in the world, in Alcobendas, Madrid. The 12×1.75m bridge was 3D printed with micro-reinforced concrete in eight segments and assembled like precast elements. We also reproduced the Arch of San Pedro de las Dueñas at Spain’s National Archaeological Museum (MAN) through 3D printing in concrete.”
The concrete 3D printed footbridge in Madrid.
The Arch of San Pedro de las Dueñas at Spain’s National Archaeological Museum.
This presented a business opportunity. The next step for ACCIONA was to identify a market to launch it services. Considering ACCIONA’s prominence in the Middle East combined with Dubai’s 3D printing strategy to make the city a world-class 3D printing hub by 2030, the company decided to open its 3D printing centre in Dubai.
Luis Clemente, COO-3D Printing, ACCIONA.
“Dubai is the place to be when it comes to the state-of-the-art technologies, especially regarding concrete 3D printing as it is underpinned by the Dubai’s commitment to a 3D printing strategy,” says Clemente.
ACCIONA’s 3D printing centre in Dubai houses the world’s largest operational 3D printer, a 6x3x2m machine which uses powder bed technology suitable for generating highly resistant structural parts. Power bed technology allows the creation of three-dimensional parts through the superimposing of successive layers of material automatically. The technique facilitates the production of highly complex pieces from 3D digital models. Introducing concrete as the base material offers additional durability and strength, particularly for architectural, urban and building applications.
A 3D-printed object at ACCIONA’s 3D printing centre in Dubai.
Large-scale 3D printing in concrete offers the possibility of constructing structural elements with total freedom of form, without the need for molds or formwork, which permits a more efficient development of complex structures. The technology also employs less energy and resources in producing concrete building elements.
The average time required to manufacture parts on the 6x3x2m printer ranges from 1–3 days depending on the finishing requirements. To speed up the process, ACCIONA has installed a second flatbed component, which can be interchanged to double the production capacity.
“The printer allows greater efficiency and automation of the construction processes. With the current size of the printer, we could manufacture the Madrid footbridge in two pieces. We have achieved concrete compressive strengths of up to 50MPa, and we continue our R&D process to achieve higher strength and durability. The biggest opportunity in this 3D printing technology is that it offers a freedom of architectural and urban design that had previously been unthinkable. It also opens the way to scientifically documenting heritage items and making replicas from their digital copies, which enables the public to contemplate identical reproductions,” says Clemente.
