RU2297991C1 - Dry construction mixture - Google Patents

Abstract

FIELD: building materials industry; production of the building mortars.

SUBSTANCE: the invention is pertaining to the building materials industry and may find application at preparation of the building mortars used for the cellular concrete blocks laying. The technical result of the invention is the increased coefficient of the construction quality and the water-retaining capability. The dry construction mixture, which includes cement, lime, sand, and as the filler contains the preliminary crushed and dried up to the constant mass diatomite at the following components ratio (in mass %): cement - 25-30, lime - 4-6, diatomite - 20-30, sand - the rest.

EFFECT: the invention ensures the increased coefficient of the construction quality and the water-retaining capability of the produced cellular concrete blocks made out of the presented dry construction mixture.

2 tbl

Description

The invention relates to the building materials industry and may find application as mortars for laying blocks of gas, pono and cellular concrete.

There are several types of mortars for masonry blocks of gas, pono and cellular concrete. As a rule, they include mineral binder and various additives. However, the use of additives, along with improving the plastic properties of mortars, leads to a significant increase in the cost of dry building mixtures. In addition, similar domestic additives cannot be used in dry mixtures due to their production in the form of dispersions, and the known dry plasticizers of type C-3 in solutions with a high water content do not have the required effect on the technological properties of the mortar mixture.

At the same time, there is another way to increase the water holding capacity of masonry mortar, which boils down to the use of finely dispersed fillers in dry construction mixtures. This allows not only to obtain the required physical and mechanical characteristics of the solution during operation, but also the required properties for the period of masonry work. In addition, the use of special additives is excluded, the cost of the dry building mix produced is reduced.

The closest technical solution is a building mixture, including in wt.%: As a binder - a hydraulic binder 10-28; slaked lime 5-20; as a light filler - granular calcium silicate 10-60; as aggregate - classified sand up to 55, and other additives (see DE, application 3930458, CL 04B 28/02, publ. 21.03.1991).

The disadvantage of this composition is the insufficiently high water retention capacity required for laying blocks of gas, pono and cellular concrete. In addition, obtaining granular calcium silicate requires additional financial costs.

The technical result is to increase the water holding capacity of the mixture.

The technical result is achieved by the fact that the dry building mixture, including cement, lime and sand, as a filler contains pre-crushed and dried to a constant mass of diatomite in the following ratio of components, wt.%:

Cement 25-30 Lime 4-6 Diatomite 20-30 Sand rest

The introduction of the filler leads to stabilization of the cement test - filling the space between the grains of cement, increasing the number of contacts between them, while the adhesion forces between the particles increase, which significantly reduces the possibility of separation of the mortar mixture. An increase in the intensity of the forces of interaction between particles, an increase in the packing density leads to an increase in the ability to retain water in a cement paste. When replacing a part of cement with diatomite, adsorption of filler particles on the surface of the cement and aggregate occurs and their bonding to each other. As a result, the attractive forces between the cement and the aggregate increase, which leads to an increase in the highest plastic viscosity.

For testing a dry mixture of the specified composition, a mortar is prepared, the water-solid ratio is 0.6. Tests are performed on samples - cubes measuring 70.7 × 70.7 × 70.7 mm, solidified under normal conditions for 28 days. Technical characteristics and compositions of dry building mixtures are given in tables 1 and 2.

Table 1 Structure The ratio of components in wt.%: cement lime diatomite diatomite granular calcium silicate one 25 5 thirty 40 - 2 27.5 5 25 42.5 - 3 thirty 5 twenty 45 - four 25 5 twenty fifty - Prototype twenty 10 - fifty twenty table 2 Specifications Structure one 2 3 four known for the prototype Water retention capacity,% 98 96 94 94 82 The average density, kg / m ³ 1400 1450 1480 1470 1500 Compressive strength, MPa 7.0 7.5 8.0 7.5 7.0

From an analysis of the data it can be seen that the described dry mortar provide lightweight mortar with high water retention capacity.

Claims (1)

Dry building mix, including cement, lime, sand, filler, characterized in that as a filler it contains pre-crushed and dried to constant mass diatomite in the following ratio of components, wt.%: Cement 25-30 Lime 4-6 Diatomite 20-30 Sand Rest