CONCRETE MIX FOR LAYER-BY-LAYER EXTRUSION (3D PRINTING) Russian patent published in 2022 - IPC C04B28/04 

FIELD: building materials industry.

SUBSTANCE: invention relates to building materials industry and can be used for the manufacture of building products and structures in additive manufacturing technology by layer-by-layer extrusion (3D printing) of a concrete mixture based on Portland cement, sand, finely ground pozzolan component, superplasticizer and polyphenylethoxysiloxane. The concrete mixture for layer-by-layer extrusion using 3-D printing includes Portland cement, sand, superplasticizer and water. Portland cement contains tricalcium silicate - 68.1 wt.%, tricalcium aluminate - 7.2 wt.%, quartz sand with a fineness modulus of 2.2 - 2.4 and a moisture content of 1-2% is used as sand, MasterRheobuild 183 based on naphthalene sulfonates is used as a superplasticizer, and additionally the mixture contains a finely ground pozzolan component - metacaolin with hydraulic with an activity of at least 1200 mg/g, a grinding degree of at least 2000 m2/kg and polyphenylethoxysiloxane "FES-50" with the following component content, wt.%: portland cement – 21.0-24.0, sand – 60.64-64.20, superplasticizer – 0.21-0.24, metakaolin – 2.1-2.4, polyphenylethoxysiloxane "FES-50" - 0.010-0.012, water – 12.480-12.708.

EFFECT: reducing the consumption of Portland cement and superplasticizer in the concrete mixture, increase shape stability and ensure the absence of defects in the form of ruptures of layers printed from the concrete mixture with the possibility of concrete mixture extrusion using construction 3D printers implementing the method for layer-by-layer extrusion, reducing shrinkage deformations, water absorption, increasing the bending strength of hardened composites printed on 3D-printer (without using moulds).

1 cl, 2 tbl