CONCRETE MIXTURE FOR 3D PRINTING Russian patent published in 2022 - IPC C04B28/04 

FIELD: building materials.

SUBSTANCE: invention relates to the building materials industry and can be used for the manufacture of building products and structures in the additive manufacturing technology by layer-by-layer extrusion (3D printing) of a concrete mixture based on Portland cement, sand, finely ground pozzolanic component and superplasticizer. The 3D printed concrete mix includes Portland cement, sand, superplasticizer and water. Portland cement contains 68.1 wt.% tricalcium silicate and 7.2 wt.% tricalcium aluminate, quartz sand with a fineness modulus of 2.2-2.4 and a moisture content of 1-2% is used as sand, and additionally, the concrete mixture contains finely ground pozzolanic component - biosilica with a specific surface area of ​​at least 1100 m2/kg and hydraulic activity of at least 1400 mg/g, and "Relamix PK" is used as a superplasticizer - a copolymer based on polyoxyethylene derivatives of unsaturated carboxylic acids with the following content of components, wt.%: Portland cement - 20.0-23.0, sand - 63.99-67.48, superplasticizer "Relamix PC "- 0.20-0.23, finely ground pozzolanic component - biosilica - 2.0-2.3, water - 10.32-10.48.

EFFECT: reducing the consumption of Portland cement and superplasticizer in the concrete mixture, increasing the dimensional stability and ensuring the absence of defects in the form of ruptures of printed layers from the concrete mixture with the possibility of its extrusion on building 3D printers that implement the layer-by-layer extrusion method, reducing shrinkage deformations, water absorption, increasing the flexural strength of the hardened composites printed on a 3D printer (without the use of molds).

1 cl, 2 tbl