3D Printing Lightweight, Insulated Walls Using Cement

Harnessing the power of moldless manufacturing through large-scale robotic 3D printing, research at ETH Zürich in collaboration with FenX AG delves into the use of cement-free mineral foam made from recycled waste. The objective is to build wall systems that are monolithic, lightweight, and immediately insulated, minimizing material use, labor requirements, and associated costs.

Cement-free mineral foam is a porous material that can be applied in varying densities, strategically distributing insulation and strength where needed. This technique optimizes the thermal performance and energy consumption necessary to heat interior spaces. Furthermore, by using a single material with different densities, it facilitates the future reuse and recycling of its parts, which already have a lower carbon footprint than plastic or aerated concrete foams.

The specific project is called Airlements. With a height of 2 meters, Airlements is a prototype of a wall made up of the assembly of four 3D printed parts. Each hollow segment weighs 25kg and was printed in less than an hour, then allowed to harden over the course of a week in a controlled environment. Operating in a temperature range of 20 to 28 degrees Celsius and a relative humidity of 20 to 70%, this configuration eliminates the need for energy-intensive processing, a significant advance over previous studies involving cement-free mineral foams. The corrugated texture of each piece provides greater strength and structural integrity to the final structure.

To transform it into a cohesive monolithic system, the hollow core can be filled with mineral foam and sealed with a protective covering of cementless plaster. In this way, they can be used as non-structural exterior walls. Additionally, the casting process allows for the seamless integration of reinforcements and infrastructure facilities, expanding the potential applications of this technology. As the research progresses, emphasis will be placed on improving the load capacity of the resulting elements and refining the manufacturing precision of the 3D printing system.

Team DBT: Patrick Bedarf, Anna, Szabo, Prof. Benjamin DillenburgerTeam FenX: Alex Heusi, Aybige, Öztüre, Lex Reiter, Enrico Scoccimarro, Michele Zanini, Etienne JeoffroyTechnical Support: Tobias Hartmann, Cilgia Salzgeber, Jonathan Leu, Lucas Petrus, Philippe Fleischmann, Michael Lyrenmann, Heinz Richner, Bharath Seshadri, Angela YooPhotography: Hyuk Sung KwonFunding: Innosuisse 41905.1 IP-EE