3D-printed concrete: Construction and climate resilience possibilities

As a leading authority on engineering and architectural practice, WSP is helping construction clients find new and effective ways to add 3D-printed concrete (3DPC)—a form of automated fabrication that reduces labor cost, planning time and waste—to their project menus. With 3DPC, a robot layers beads of mortar-like material to build structures from the ground up. This allows users to print odd shapes without formwork and is ideal for vertical construction.

Los Angeles-based RCAM Technologies Inc., whose specialty 3DPC elements underpin renewable energy infrastructure, has enlisted WSP for design tool and test protocol development; feasibility, economic and environmental studies; fabrication and assembly planning; fabrication site searches and evaluation; port facility layout development; plus, risk identification and mitigation.

“WSP’s technical support has been critical to several of our projects, including the development of support structures for land-based, fixed bottom, and floating wind,” says RCAM CEO Jason Cotrell. “With their help, we are able to simultaneously develop our broad portfolio of concrete products, including towers, anchors, and floating platforms while maintaining a lean, fast-moving, and agile core staff.”

According to WSP Maritime Division Vice President Markus Wernli, 3DPC is not expected to replace, but rather complement traditional cast-in-place and precast concrete construction methods, and “become another tool in the toolbox for the construction industry. With RCAM Technologies, we are taking part in developing a new innovative construction methodology, and finding solutions for combatting climate change. We’re doing this by developing sustainable structures for the renewable energy sector that can be built cost effectively, expediently and in large numbers, despite the current labor shortage.”

“WSP has led and participated in programs for emerging technologies such as 3DPC, all in collaboration with private companies, federal laboratories, universities, subject experts and the U.S. Departments of Defense, Energy and Transportation,” he adds. 

3D printing concepts and robotic construction methodologies promise several exciting aspects for development, and invite fast-setting concrete materials with the potential of expanding to more sustainable materials, such as geopolymers. Then there are the technology’s new design possibilities that allow for structures that were not possible with conventional construction methods. 

WSP has a long history of supporting clients eyeing new technologies for the heavy infrastructure sector, Wernli observes. Team members understand how to develop innovative designs that are not covered by current standards and that need to be based on principle mechanics, finite element analyses, plus material and structural testing that follow strict rules for technology qualification towards certification by accredited third parties.

WSP and RCAM Technologies are working on several innovative 3DPC applications, including this printing of a tower wall section.

WSP and RCAM Technologies are working on several innovative 3DPC applications. They include wind turbine towers and land-based turbine foundations; support structures for offshore wind turbines; anchors for floating offshore wind turbines, as well as deep-sea pumped, hydroelectric storage units; and, floating offshore solar energy structures.

“Our applications and designs will fully engage the benefits of 3DPC,” Wernli affirms. “There’s already exponential growth in this technology’s use and development. The technology is impacting the housing sector and its reach is expected to eventually expand into heavy infrastructure. At this point, WSP and our clients can learn how 3DPC can be used now and into the future. The use of 3DPC will first grow in less challenged structural and non-structural components before finding application in components for large infrastructure.”

The unique features of 3DPC also contribute to the challenges companies face when implementing the technology in their projects. For example, while the printing process is suitable for vertical construction, it’s challenging for horizontal structural components. 

Additionally, there’s not yet an ideal solution for the printing process to reinforce concrete components. This is because the material is orthotropic, meaning it behaves different when loaded in one direction than in another direction.

WSP’s work to help design and configure 3D-printed structures addresses these challenges. The firm continuously engages in a feedback cycle with industry practitioners to identify potential solutions and improve current printing technologies, and to help clients like RCAM realize projects beyond construction codes that weren’t written with 3DPC considerations.

Along with codes and standards factors, WSP is gauging the workforce development factor attending 3DPC method uptake. “Automation will cause a shift in labor skill from the more traditional construction worker to printing operators and maintenance workers,” Wernli explains. “Additional workforce will be needed for the planning and programming for printing, printer setup, and development of future generation printers and materials.”

“Environmental stewardship is another important aspect that needs to be considered for the future success of 3DPC,” he continues. “This includes the development of low carbon and energy footprint materials. Other, non-cementitious materials are already in development such as polymer concrete and wood composites.” — WSP, New York