RU2674353C1 - Complex additive for foam concrete mixture - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to constructional materials and can be used as a complex additive to a mortar mixture when producing foam concrete. Complex additive for concrete mix contains, wt. %: foaming additive based on protein 75–80, red blood salt 20–25.

EFFECT: increased tensile strength during bending and index of crack resistance of foam concrete.

1 cl, 1 tbl, 1 ex

Description

The invention relates to building materials and can be used as a complex additive in the mortar mixture in the production of foam concrete.

Known complex additive for foam concrete mixture containing sodium chloride in an amount of 58.8-71.4, a protein-based foaming additive in an amount of 8.2-11.8, a sol of silicic acid in an amount of 20.4-29.4 (RU No. 2381192, С04В 24/14, publ. 02/10/2010).

Closest to the proposed invention is a complex additive containing a foaming additive on a protein basis and a sol of silicic acid in the following ratio of components, wt. %: protein-based foaming additive - 3.7-4.2, silica sol - 95.8-96.3, (RU No. 2377207, С04В 22/08, С04В 24/14, С04В 38/10, publ. 12/27/2009).

The disadvantages of such complex additives are insufficient physical and mechanical properties: tensile strength during bending and fracture toughness of the resulting foam concrete.

The objective of the invention is to increase the tensile strength in bending and the fracture toughness index as a ratio of foam concrete.

The technical result of the invention is achieved in that a complex additive for a foam concrete mixture containing a protein-based foam-forming additive additionally contains red blood salt, K ₃ [Fe (CN) ₆ ] in the following ratios of components, wt. %:

Protein Based Foaming Agent 75-80 Red blood salt 20-25

Concrete example

A complex additive containing a protein-based foaming additive and red blood salt is used to prepare building foam with the following ratios of components, wt%:

Protein Based Foaming Agent 75-80 Red blood salt 20-25

The following brands can be used as a protein-based foaming additive: Addiment SB 31L (dark brown liquid, foaming pH range: 6-10; the main active substance is proteine hydrolyzate (Khitrov A.V., abstract for the competition) Doctor of Technical Sciences “Technology and properties of foam concrete, taking into account the nature of the foam introduced.” St. Petersburg: PGUPS, 2006); scope: as an additive for the production of foam concrete; trademark RENIMENT SB 31L; manufacturing company “SIKA ADDIMENT GmbH” B-69171 Leimen, Germany), as well as FOAMCEM (the main active substance is proteingid Rolizate; scope: foaming agent for the preparation of lightweight cellular concrete; manufacturer Lastonltaliana SPA) and GreenFroth-P (the main active substance is proteine hydrolyzate; scope: for the production of foam concrete, as well as for the manufacture of light wall and decoration; manufacturer ISOLTECH sncdiScarpa & С ViaC. Colombo, 41 24020 RANICA (BG), Italy).

Red blood salt is a reagent (techn.) “Potassium iron-hydrogen” - K3 [Fe (CN) 6], obtained by oxidation of potassium hexacyanoferrate with chlorine or bromine in a hydrochloric acid medium. GOST 6816-79, manufacturer - Reahim JSC.

Below are the results of a study of the proposed complex additives for foam concrete mix.

Cement sand mixture composition, wt. %: Portland cement grade M400-D20 - 70%, sand SiO ₂ - 30% is closed with water at a water-binding ratio (W / B) of 0.40.

A concentrated foaming additive based on protein FOAMCEM is dosed with a percentage concentration of the main substance of 70% in the amount of 0.43% by weight of cement, red blood salt in the amount of 0.4%) by weight of cement, water in the amount of 14% by weight of cement is mixed in polyethylene containers and get a solution of a foaming additive. Using a foam generator, building foam is obtained. The resulting construction foam is mixed with the prepared cement-sand mixture to obtain a homogeneous foam concrete mixture.

Foam concrete samples made with the proposed complex additive harden under natural conditions. After 28 days of hardening, the samples are tested in accordance with GOST 25485-89 "Cellular concretes. Technical conditions. " The results are presented in the table.

Analysis of the results shown in the table indicates that the introduction of the specified complex additives for foam concrete mixture leads to an increase in tensile strength in bending and fracture toughness of the material in comparison with the values achieved when using the prototype.

Claims (2)

Complex additive for foam concrete mixture, including a protein-based foam-forming additive, characterized in that it additionally contains red blood salt in the following ratio of components, wt.%: protein-based foaming agent 75-80 red blood salt 20-25