The centrepiece of the exhibition is a vaulted structure consisting of 399 individual limestone blocks that stand in pure compression, without any structural connection, mortar or reinforcement. The sinuous stone surface covers 75 m2 and spans more than 15 m in multiple directions. Only 5 cm thick in some places, which is proportionally half as thick as an eggshell, the unreinforced stone vault questions the misconception that expressive form need go hand-in-hand with inefficient use of material.
For the exploration of exciting structural compression forms, the BRG has developed computational, graphical design methods based on the centuries-old technique of “graphic statics”. The spectacular vaulted structure has been realised by combining these novel structural design methods with new possibilities in the field of digital fabrication and the experience of expert stone masons. A contemporary equivalent of a Gothic cathedral, this stone vault perfectly materialises BRG’s philosophy: “Learning from the past to design a better future.”
In line with this philosophy, the message of the “Beyond Bending” exhibition is strengthened further by two prototypes of optimised, compression shell floor systems based on traditional tile vaulting. The first prototype is a 2 cm-thick, unreinforced, concrete construction that, because of its specific shape in compression, uses 70% less material than a conventional floor slab. The second prototype is based on the same structural principle, but constructed using 3D sand printing technology. It demonstrates what fully-bespoke structural solutions might look like in the not too distant future. At the end of the Arsenale site stands a second, large vaulted project designed by the two creative structural designers. The “Droneport” is a prototype for the development of small modular airports for unmanned cargo planes. By 2019, a network of “droneports” should facilitate the delivery of medicine and blood to remote, inaccessible areas all over Rwanda. The masonry vault was engineered such that it could be built by local communities using the Catalan tile-vaulting technique, with a minimum amount of supporting scaffolding. Furthermore, because of its specific compression geometry, humble materials can be used, such as unfired earthen tiles, pressed using local soil. The “Droneport” is a project by the Norman Foster Foundation and is part of the Red Line initiative by AfroTech EPFL that develops “drone networks” for Africa and other emerging economies.
The Block Research Group at ETH Zurich is co-directed by Philippe Block and Tom Van Mele. The two Belgians graduated together in 2003 as architectural engineers from the Vrije Universiteit Brussel.