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

FIELD: building materials.

SUBSTANCE: invention relates to the field of building materials industry and can be used for the manufacture of building products and structures in the technology of additive manufacturing by layer-by-layer extrusion (3D printing) of a concrete mixture based on Portland cement, sand, finely ground pozzolanic component, superplasticizer and sodium methyl siliconate. Modified concrete mixture for building 3D printing includes Portland cement, sand, superplasticizer and water. Portland cement contains, wt.%: tricalcium silicate 68.1, tricalcium aluminate 7.2, quartz sand with a fineness modulus of 2.2 - 2.4 and a moisture content of 1-2% is used as sand, a superplasticizer based on polycarboxylate esters "MasterGlenium 430", and additionally it contains a finely ground pozzolanic component - diatomite with a hydraulic activity of at least 1500 mg/g, degree of grinding not less than 1400 m²/kg and sodium methyl siliconate "GKZH-11N" with the following content of components, wt.%: Portland cement - 20.0-23.0, sand - 62.63-66.37, superplasticizer "MasterGlenium 430" - 0.20-0.23, finely ground pozzolanic component - diatomite - 2.0-2.3, sodium methyl siliconate "GKZH-11N" - 0.010-0.012, water - 11.420-11.828.

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

1 cl, 2 tbl