The Minimass beam is a 3D printed reinforced concrete beam that uses less concrete and less steel than conventional beams.

Minimass was developed by Andy Coward, founder of the company Net Zero Projects Limited. The prefabricated concrete beam is made by precisely placing the minimum materials without any waste. The beam uses concrete and steel like conventional beams, but saves up to 70% embodied carbon and up to 50% of material costs.

The beam uses 78% less concrete and 70% less steel than conventional beams. It is designed to create stiffness and strength through axial compression and tension. The tension capacity is provided by standard post-tensioning cables with standard post-tensioning anchors. By using 3D printing, waste is eliminated, as no formwork is needed.

Minimass has been designed to be used to replace any other type of beams, both in buildings and in bridge construction.

Currently, a series of 6m long physical prototypes have been printed and tested for deconstructive load testing. Deconstructive testing has been taking place using a 4-point bending test, with strain and displacement throughout.

Photos: Andy Coward / Minimass