Mechanical Properties of a 3D-Printed Wall Segment Made with an Earthen Mixture

Materials (Basel). 2022 Jan 7;15(2):438. doi: 10.3390/ma15020438.

Abstract

This study provides a contribution to the research field of 3D-printed earthen buildings, focusing, for the first time, on the load-bearing capacity of these structures. The study involves the entire production and testing process of the earthen elements, from the design, to the preparation of the mixture and the 3D printing, up to the uniaxial compression test on a wall segment. The results indicate that 3D-printed earthen elements have a compressive strength of 2.32 MPa, comparable to that of rammed earth structures. The experimental data also made it possible to draw conclusions on the action of the infill, which seems to have the function of stopping the propagation of cracks. This has a positive effect on the overall behavior of 3D-printed earthen elements, since it avoids the onset of dilative behavior in the final stages of the load test and maintains ultimate load values higher than 50% of the maximum load.

Keywords: 3D printing; Poisson’s ratio; biocomposites; crack propagation; earthen buildings; load-bearing walls; mesoscale behavior; microscale behavior; orthotropic material; volumetric strain.