Printing 3D sand: strength and design freedom in concrete

August 20th, 2018 / By: / Out There

Glass fiber-reinforced concrete is sprayed on the 3D printed formwork in several consecutive layers. Photo: Digital Building Technologies (DBT) ETH zürich / andrei jipa

Researchers in Switzerland have fabricated a lightweight 80-square-meter concrete slab ceiling that uses 3D sand printing for its formwork. The ceiling consists of 11 segments of Smart Slab, which is 20 millimeters at its thinnest point and is reported to be less than half the weight of a conventional concrete ceiling, although even at half the weight, the project tips the scale at 15 tons.

The Smart Slab segments were placed piece-by-piece on a 12-centimeter-wide mesh mold wall, which supported the concrete while it cured. After a two-week hardening process, the segments were ready to be installed.

Developed by the research group of Benjamin Dillenburger, assistant professor for digital building technologies at ETH Zurich, Smart Slab is one of the core elements of DFAB HOUSE. The group combines the knowledge and expertise of science and technology professors and industry experts, who are exploring and testing how digital fabrication can change architecture.