California-based practice Emerging Objects has developed a 3D printed structural column inspired by ancient Incan techniques, which it is claimed can stand up to earthquakes.
The column's earthquake-resilient properties can be achieved by using masonry principles that diffuse the force of an earthquake through the interlocking components of a wall.
The idea for the Quake Column draws from traditional Incan ashlar techniques which had to contend with the highly seismic land of Peru. For centuries, the Incans used mortar-free construction, which proved to be more earthquake-resistant than using mortar.
The interlocking stone structures of the ancient race removed resonant frequencies and stress concentration points, while the dry-stone walls could also move slightly during an earthquake and resettle without the walls collapsing.
This passive structural control technique thus employs both the principle of energy dissipation and that of suppressing resonant amplifications.
In addition Inca walls also tend to incline inwards by three to five inches and the corners were rounded, which helps contribute to their stability.
The 3D printed approach has also provided a number of other benefits.
- Each “stone” that comprises the Quake Column interlocks perfectly with neighbouring blocks
- Whereas the cyclopean blocks of Incan construction are massive and weigh several tons, the 3D printed column blocks are lightweight and hollow
- Each column block is numbered to designate its place in the construction sequence
- Each column block has a built in handle for easy lifting, control and placement of the massive 3D printed blocks
- Calculations suggest this technique could be used to fabricate building code compliant, load-bearing walls
"While this was an experiment in connectivity, we have been able to create 3-D printed parts that are much stronger than reinforced concrete in compression," Emerging Objects principal Ronald Rael said to Wired magazine. "We are also working on increasing the tensile strength of our materials using reinforcement fibres."