By David Brill
For the first time in more than a century, architects are witnessing the birth of an entirely new building system—something that hasn’t happened since the mass production of steel and glass. The additive manufacturing (3-D printing) revolution has already changed the way items like prosthetics and musical instruments are produced. Now it is providing architects with a whole new suite of construction materials.
Structures of the future will be printed one layer at a time, and UT’s College of Architecture and Design is getting in on the ground floor of 3-D printing technologies and techniques for buildings. Case in point is the Additive Manufacturing Integrated Energy (AMIE) project, the world’s first zero-energy structure created entirely by a 3-D printer and the first to reciprocally share energy with a 3-D-printed vehicle.
AMIE is a collaborative venture from the UT-ORNL-SOM Governor’s Chair for High Performance Energy Practices in Urban Environments, which includes partners UT, Oak Ridge National Laboratory (ORNL), and international architecture firm Skidmore, Owings & Merrill (SOM). James Rose, director of UT’s Institute for Smart Structures, and architecture students in the Governor’s Chair Design Studio in Energy and Urbanism contributed to the design process and were engaged at the project’s earliest phase.
In the Beginning
Initially the students were presented with a challenge, described by Rose: “Science has given you a new material. Figure out what it wants to be and design a structure.” Professional oversight was provided throughout the process by Governor’s Chair Philip Enquist and Lucas Tryggestad of SOM’s Chicago office.
Some of the students took design cues from nature and studied bones and nautilus shells. “Like 3-D-printed materials, bones and shells are built layer upon layer,” Rose said. “They’re also lightweight and remarkably strong, qualities that we knew would be important for the AMIE structure.” Other students explored the art of origami, which turns a flat sheet of paper into a 3-D object.
The students brought their ideas to life using the powerful computers and small-scale 3-D printers at UT’s Fab Lab. Each rendering reflected the character of the material it was inspired by: open vertical cavities found in bones, adjoining chambers similar to those in nautilus shells, and origami’s ridges and valleys.
AMIE’s final form—designed by SOM in collaboration with Rose and ORNL—echoes elements found in the student projects.
For instance, the shell group created a series of printed rings, representing walls, ceiling, and floor, which could be joined to form the structure’s open, unsupported interior. AMIE features ten of these interlocking rings, each formed from two C-shaped components joined top and bottom.
The origami group proposed a partially collapsible structure with louvered sides like the bellows of an accordion. AMIE’s louvered sides have inset windows that can be positioned to allow penetration of warming sunlight in colder climates. For warmer climates, the structure can be oriented to block sunlight. The origami group also conceived a central interior island with a sink, dishwasher, stove, microwave, refrigerator, and bed.
Although the work of the bone group does not apply directly to the final design, it may yet influence future 3-D-printed architecture. “Often, students haven’t learned yet that something is impossible,” Rose said. “And they go on to demonstrate a new way of looking at a problem.” One of 3-D printing’s limitations is the inability to print unsupported horizontal structures because the thread of molten plastic will collapse before it can harden. The bone group solved the problem by printing a barrel arch that leveraged the print head’s ability to deposit material at a 40-degree angle. The structure’s walls incrementally gained thickness with each pass until they joined at the center of the interior space.
Some Assembly Required
Parallel to the student work, architects from SOM completed the final design and delivered it to ORNL as a computer file. All of AMIE’s parts were formed by layering building material—a polymer blended with 20 percent carbon fiber—extruded from ORNL’s big area additive manufacturing printer’s print head.
The composite parts were then transported to Clayton Homes in Andersonville, Tennessee, for assembly of the twelve-foot-wide by thirteen-foot-high by thirty-eight-foot-long structure. From the moment the students were engaged to finished product took only nine months. AMIE then embarked on a US tour in the fall of 2015.
Rose believes adaptations of AMIE’s basic design and 3-D construction have many potential applications such as military barracks, refugee shelters, and micro-apartments for students. Because 3-D printers have a modest energy demand and can be made portable, structures can be printed on-site. And since the process is so precise, there is very little waste.
Architecture is an iterative process, and successful practitioners look into the future even as they glance back at the past. Barrel arches, for example, trace back to the Roman Empire. But the students were able to use a novel building system to give the arch new expression.
Architecture is also an additive process—like 3-D printing itself—ever building on past innovations. Rose’s Governor’s Chair studio is already devising the next phase of AMIE’s evolution: individual 3-D-printed modular rooms that will snap together like Lego bricks and stack to create high-density housing.
As for the configuration and features of the rooms themselves—including 3-D-printed fixtures and even furniture—the decisions would be left up to the occupants. From a design perspective, 3-D printing enables a shift from mass production to mass customization.
“With 3-D printing, there’s no penalty in cost or materials for printing every part differently,” Rose said. “And 3-D printing also liberates architects from the hard edges imposed by traditional building materials and allows them to create fluid lines.”
Granted, it’s a large leap from miniature snap-together rooms to a habitable apartment building. But even Christopher Wren began St. Paul’s Cathedral with a scale model and a vision.