Timbrel Vaults, also known in America as Guastavino vaults after their most famous practitioner, are incredibly thin structures that Kris De Decker says "allowed for structures that today no architect would dare to build without steel reinforcements. The technique was cheap, fast, ecological and durable." I described them briefly in Crossway Zero Carbon Home Brings Back the Timbrel Vault, but the definitive post is Kris De Decker's 2008 Tiles as a substitute for steel: the art of the timbrel vault.
The art of building the timbrel vault like Rafael Guastavino used to do is pretty much dead, as is the art of bricklaying like Eladio Dieste of Uruguay used to do. But ETH Zurich University is saving both by using computers and robot technology to do what few humans can any more. Kris De Decker reports on the work of Lara Davis, Matthias Rippman and Philippe Block from the Swiss BLOCK Research Group at the ETH Zurich University, where they reinvent the timbrel vault. They design it in Rhino (with an addon they are giving away) build up formwork out of pallets and computer-cut cardboard;
They then set the thin tiles on the cardboard formwork with quick setting cement. Kris notes that the traditional method was much more economical in its use of formwork, but the new technique is still pretty efficient. He quotes the designers:
The cardboard formwork implemented in this project is fabricated with 2-D CAD-CAM cutting and gluing processes and is assembled on site. The system's rapid fabrication, lightweight transportation, and speed of erection and de-centering dramatically reduce the material and labour-based costs of construction. An inexpensive and potentially reusable/recyclable material, this lightweight cardboard formwork extends the viability of thin-tile vaulting to freeform construction.
They have even thought about how to drop the formwork easily: just add water.
The entire formwork sits on top of a series of sealed plastic tubes containing cardboard spacers. Each spacer, which consists of a folded stack of cardboard sheets, taped together, supports the corners of typically four palettes. After the vault is completed, the tubes are filled with water, saturating the cardboard, causing it to compress under the load of the palettes and effectively to lower the formwork.
The strength of these vaults is really hard to believe, given their thinness and lack of reinforcement. Here you can see them being load tested to destruction.
The Block Research Group's motto is Learning from the past to design a better future. They are certainly living up to it. From Kris De Decker at No Tech Magazine; read also his history of the Timbrel Vault.