“A lightweight concrete ceiling with formwork 3D-printed from sand is among the innovations to feature in an experimental robot-made house built by university ETH Zurich.

The DFAB House, currently under construction in Dübendorf, Switzerland, showcases five digital building methods that have never before been seen in architecture, and the concrete Smart Slab is the latest addition.

The structure has been computationally designed to use only the minimal amount of material necessary to make it load-bearing, and is less than half the weight of usual concrete slabs.

The light weight form was enabled by using 3D sand printing to…”

Source:
http://www.impactlab.net/2019/04/19/eth-zurich-makes-lightweight-concrete-ceiling-using-3d-sand-printing/