Construction mortars are mixtures of binder, water and fine aggregate, which acquire a homogeneous stone-like structure as a result of the hardening process. Before hardening, they are called mortar mixtures and are used for masonry walls, foundations and plastering the surfaces of various structures.

Based on the type of binders and additives, a distinction is made between cement, lime, cement-lime, cement-clay and some other combinations.

Based on the properties of the binder, solutions are divided into air solutions, made with air binders (lime, gypsum), and hydraulic solutions, made with hydraulic binders (cements of various types).

Based on the type of fillers, a distinction is made between heavy solutions, with natural sands, and light ones, with porous fillers.

In terms of composition, mortars can be simple, with one binder (cement, lime) and mixed, which usually contain two, less often three binders or one binder with an inorganic additive (cement-lime, lime-clay, etc.).

Air mortars are used for the construction of stone structures operated in a dry environment, and hydraulic mortars are used in a wet environment.

Heavy solutions, where the filler is quartz sand, have a bulk density of more than 1600 kg/m3; light - less than 1500 kg/m3, the filler in them is sand from expanded clay, ground slag, etc.

The strength of the solution is determined by its brand (the numbers indicate compressive strength in kgf/cm2).

Waterproof mortars are used to make structures waterproof (for example, a 1:2 cement mortar with the addition of liquid glass).

Materials for mortars

To prepare solutions, binders, fillers and additives are used.

Binding materials include puffed lime in the form of dough, fluff and quicklime, building gypsum, Portland cement, etc.

The filler for mortar mixtures is natural or artificial sand.

Air lime It hardens only in air, which is why it is called air. It can be quicklime (boiling lime), ground or slaked into powder (fluff lime). Quicklime is greyish-colored pieces; ground - fine grayish powder.

Lime is slaked in a slaking box or barrel. In large quantities slaked lime stored in a creative pit dug in the ground and lined with boards. Most often, lime is used in the form of dough or fluff lime.

Construction gypsum rarely used in mortars, mainly for work in dry conditions, but as an additive to limestone plaster solutions- Often. In lime mortars, gypsum increases strength and reduces setting and hardening time.

Gypsum- This is a white or grayish finely ground powder. Gypsum mixed with water, depending on its purpose, has a beginning of setting of 2-20 minutes and an end of setting of 15-30 minutes or more.

If necessary, you can extend the setting time of the gypsum by adding a retarder. To do this, add 5-20% lime paste, or 5-10% borax, or 0.5-2% hide glue to the mixing water, based on the weight of the gypsum. These additives allow you to extend the setting time of gypsum to 40–60 minutes.

Portland cement is the strongest binding material. It has grades: 200, 300, 400 (the numbers indicate compressive strength in kgf/cm2). Portland cement is a grayish-green, finely ground powder. To obtain solutions various properties and purpose, varieties of Portland cement are used: white (or colored based on white), quick-hardening, hydrophobic, construction, sulfate-resistant, plasticized, pozzolanic and slag Portland cement.

Setting of cement, as a rule, occurs no earlier than 45 minutes and ends no later than 12 hours after mixing with water.

It must be taken into account that during the storage of cement, its activity drops by approximately 5% per month. Based on this, you should purchase freshly made, not stale cement. Its quality is determined visually by the sign of pelletization or by touch: fresh cement flows out of a handful, and stale cement forms a lump, because it has already absorbed moisture. As long as the lump can still be kneaded with your fingers, the cement is considered suitable for use, but its dosage is usually increased by 20–50%.

Filler sands There are natural (heavy) - quartz, feldspathic - or artificial.

The coarseness of the sand should correspond to the thickness of the seam and the nature of the masonry. So, for rubble masonry, sand with grains no larger than 5 mm is used, and for brick masonry - no larger than 3 mm.

The grain size of the sand is approximately determined by touch. The grain sizes of coarse sand are more than 2.5 mm, medium - from 2 to 2.5 mm, fine - less than 1.5 mm.

In mortars, aggregates typically occupy 60-65% of the volume.

For solutions of grades 25 and 50, the permissible contamination of sand with clay and dust is no more than 10%, for a solution of grade 10 - up to 15%. If necessary, the sand is washed.

Shell sands, granulated boiler and blast furnace slags, and expanded clay sand are used as lightweight aggregates.

Depending on the density, artificial sand is divided into grades according to bulk density from 250 to 1100 (the numbers indicate the bulk density of sand, kg/m3).

Clay is introduced into lime and cement mortars as an additive in quantities by volume to cement 1:1. The addition of clay improves the grain composition, increases water-holding capacity, improves workability, and increases the density of the solution.

Clay is made up of different minerals, so it comes in different colors.

There are thin, medium and fat clays. Skinny ones are usually used in their pure form, medium and fatty ones are added to the solution in smaller quantities.

Preparation of masonry mortars

Masonry mortar can be prepared in a concrete mixer with a capacity of 0.15 m3 or manually.

Cement mortar prepared almost similarly to concrete. In a metal or wooden box made of boards 25–30 mm thick with a bottom covered with roofing iron, dimensions 1 × 0.5 m or 1.5 × 0.7 m and a height of 0.2–0.25 m, first fill the required number of buckets in an even layer sand, on top - a full bucket of cement. Next, the mixture is shoveled until the mass is homogeneous in color, poured with a measured amount of water from a watering can and continued shoveling until a homogeneous composition is obtained.

The prepared solution must be consumed within 1.5 hours so that it does not lose strength. To prepare the solution, sand must first be sifted through a sieve with 10x10 mm cells (for masonry).

Lime paste solution prepare immediately, mixing it with sand and water until smooth.

Cement-lime mortar prepared from cement, lime paste and sand.

Lime dough is diluted with water to the consistency of milk and filtered on a sieve with 10x10 mm cells. A dry mixture is prepared from cement and sand and mixed with lime milk to the required thickness (dough consistency).

Cement-clay mortar prepared similarly to cement-lime.

Compositions (in volumetric parts) of cement, cement-lime, cement-clay for stone structures:

Compositions (in volume parts) of lime mortars:

Requirement of cement per 1 m3 of sand or cement-lime or cement-clay mortar:

GOST 28013-98

Group Zh13

INTERSTATE STANDARD

BUILDING SOLUTIONS

General technical conditions

General specifications

ISS 91.100.10
OKSTU 5870

Date of introduction 1999-07-01

Preface

Preface

1 DEVELOPED by the State Central Research and Design Institute complex problems building structures and structures named after V.A. Kucherenko (TsNIISK named after V.A. Kucherenko), Research, Design and Technological Institute of Concrete and Reinforced Concrete (NIIZhB), with the participation of JSC "Pilot Plant of Dry Mixes" and JSC "Roskonitstroy" " Russian Federation

INTRODUCED by the State Construction Committee of Russia

2 ADOPTED by the Interstate Scientific and Technical Commission for Standardization, Technical Regulation and Certification in Construction (MNTKS) on November 12, 1998.

Voted for acceptance

State name	Name of body government controlled construction
Republic of Armenia	Ministry of Urban Development of the Republic of Armenia
The Republic of Kazakhstan	Committee on Housing and Construction Policy under the Ministry of Energy, Industry and Trade of the Republic of Kazakhstan
Republic of Kyrgyzstan	State Inspectorate for Architecture and Construction under the Government of the Kyrgyz Republic
The Republic of Moldova	Ministry of Territorial Development, Construction and Communal Services of the Republic of Moldova
Russian Federation	Gosstroy of Russia
The Republic of Tajikistan	State Construction Committee of the Republic of Tajikistan
The Republic of Uzbekistan	State Committee for Architecture and Construction of the Republic of Uzbekistan

3 INSTEAD GOST 28013-89

4 ENTERED INTO EFFECT on July 1, 1999 as a state standard of the Russian Federation by Decree of the State Construction Committee of Russia dated November 29, 1998 N 30

5 EDITION (July 2018), with Amendment No. 1 (IUS 11-2002)


Information about changes to this standard is published in the annual information index "National Standards", and the text of changes and amendments is published in the monthly information index "National Standards". In case of revision (replacement) or cancellation of this standard, the corresponding notice will be published in the monthly information index "National Standards". Relevant information, notices and texts are also posted in the information system common use- on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet (www.gost.ru)

1 area of ​​use

This standard applies to mortars with mineral binders used for masonry and installation of building structures during the construction of buildings and structures, fastening cladding products, and plaster.

The standard does not apply to special solutions (heat-resistant, chemical-resistant, fire-resistant, heat- and waterproofing, grouting, decorative, tensile, etc.).

The requirements set out in 4.3-4.13, 4.14.2-4.14.14, sections 5-7, appendices B and D of this standard are mandatory.

2 Normative references

The normative documents used in this standard are given in Appendix A.

3 Classification

3.1 Construction mortars are classified according to:

- main purpose;

- the binder used;

- medium density.

3.1.1 According to their main purpose, solutions are divided into:

- masonry (including for installation work);

- facing;

- plastering.

3.1.2 According to applicable astringent solutions divided into:

- simple (on one type of binder);

- complex (on mixed binders).

3.1.3 Based on average density, solutions are divided into:

- heavy;

- lungs.

3.2 The designation of a mortar when ordering must consist of an abbreviated designation indicating the degree of readiness (for dry mortar mixtures), purpose, type of binder used, grades for strength and mobility, average density (for light mortars) and the designation of this standard.

An example of a symbol for a heavy mortar, ready-to-use, masonry, on lime-gypsum binder, grade M100 for strength, P2 for mobility:

Masonry mortar, lime-gypsum, M100, P2, GOST 28013-98 .

For a dry mortar mixture, light, plaster, on a cement binder, grade M50 for strength and mobility - P3, medium density D900:

Dry mortar plaster mixture, cement, M50, P3, D900, GOST 28013-98 .

4 General technical requirements

4.1 Construction mortars are prepared in accordance with the requirements of this standard according to the technological regulations approved by the manufacturer.

4.2 Properties mortars include the properties of mortar mixtures and hardened mortar.

4.2.1 Basic properties of mortar mixtures:

- mobility;

- water holding capacity;

- delamination;

- application temperature;

- average density;

- humidity (for dry mortar mixtures).

4.2.2 Basic properties of the hardened solution:

- compressive strength;

- frost resistance;

- average density.

If necessary, additional indicators can be established in accordance with GOST 4.233.

4.3 Depending on the mobility, mortar mixtures are divided in accordance with Table 1.


Table 1

Mobility grade P	Norm of mobility for cone immersion, cm

4.4 The water-holding capacity of mortar mixtures must be at least 90%, for clay-containing solutions - at least 93%.

4.5 The stratification properties of freshly prepared mixtures should not exceed 10%.

4.6 The mortar mixture should not contain fly ash more than 20% of the cement mass.

4.7 The temperature of mortar mixtures at the time of use should be:

a) masonry mortars for external work - in accordance with the instructions in Table 2;

b) facing mortars for facing with glazed tiles at a minimum outside temperature, °C, not less than:

	from 5 and above

c) plaster solutions at a minimum outside temperature, °C, not less than:

	from 5 and above

table 2

Average daily outside air temperature, °C	Temperature of the mortar mixture, °C, not less
	Masonry material
	at wind speed, m/s
Up to minus 10
From minus 10 to minus 20
Below minus 20
Note - For masonry mortar mixtures during installation work, the temperature of the mixture should be 10°C higher than indicated in the table

4.8 The moisture content of dry mortar mixtures should not exceed 0.1% by weight.

4.9 The standardized quality indicators of the hardened mortar must be ensured at the design age.

The design age of a solution, unless otherwise specified in the design documentation, should be taken as 28 days for solutions made with all types of binders, except gypsum and gypsum-containing ones.

The design age of solutions based on gypsum and gypsum-containing binders is 7 days.

(Changed edition, Amendment No. 1).

4.10 The compressive strength of mortars at design age is characterized by the following grades: M4, M10, M25, M50, M75, M100, M150, M200.

The compressive strength grade is assigned and controlled for all types of mortars.

4.11 The frost resistance of solutions is characterized by grades.

The following frost resistance grades have been established for the solutions: F10, F15, F25, F35, F50, F75, F100, F150, F200.

For mortars of compressive strength grades M4 and M10, as well as for mortars prepared without the use of hydraulic binders, frost resistance grades are not assigned or controlled.

4.12 The average density, , of hardened solutions at design age should be, kg/m:

	Heavy solutions	1500 or more
	Light solutions	less than 1500.

The normalized value of the average density of solutions is set by the consumer in accordance with the work project.

4.13 Deviation of the average density of the solution towards an increase is allowed no more than 10% of that established by the design.

4.14 Requirements for materials for the preparation of mortars

4.14.1 Materials used for the preparation of mortars must comply with the requirements of standards or technical specifications for these materials, as well as the requirements of this standard.

4.14.2 The following should be used as binding materials:

- gypsum binders according to GOST 125;

- building lime according to GOST 9179;

- Portland cement and Portland slag cement according to GOST 10178;

- pozzolanic and sulfate-resistant cements according to GOST 22266;

- cements for mortars in accordance with GOST 25328;

- clay according to Appendix B;

- others, including mixed binders, according to regulatory documents for a specific type of binder.

4.14.3 Cementing materials for preparing solutions should be selected depending on their purpose, type of structures and conditions of their operation.

4.14.4 The consumption of cement per 1 m of sand in mortars based on cement and cement-containing binders must be at least 100 kg, and for masonry mortars, depending on the type of structure and their operating conditions, no less than that given in Appendix D.

4.14.6 Lime binder is used in the form of hydrated lime (fluff), lime dough, and milk of lime.

Lime milk must have a density of at least 1200 kg/m and contain at least 30% lime by weight.

Lime binder for plastering and facing mortars should not contain unslaked lime particles.

Lime dough must have a temperature of at least 5°C.

4.14.7 The following should be used as a filler:

- sand for construction work according to GOST 8736;

- fly ash according to GOST 25818;

- ash and slag sand according to GOST 25592;

- porous sands according to GOST 25820;

- sand from slag of thermal power plants according to GOST 26644;

- sand from ferrous and non-ferrous metallurgy slags for concrete according to GOST 5578.

4.14.8 The largest grain size of the filler should be, mm, no more than:

	Masonry (except rubble masonry)
	Rubble masonry
	Plaster (except for the covering layer)
	Plaster covering layer
	Facing

4.14.9 When heating aggregates, their temperature, depending on the binder used, should not be higher, °C, when using:

	Cement binder
	Cement-lime, cement-clay and clay binders
	Lime, clay-lime, gypsum and lime-gypsum binders

4.14.11 The specific effective activity of natural radionuclides of materials used for the preparation of mortar mixtures should not exceed the limit values ​​depending on the area of ​​application of the mortar mixtures according to GOST 30108.

4.14.12 Chemical additives must comply with the requirements of GOST 24211.

Additives are introduced into ready-to-use mortar mixtures in the form of aqueous solutions or aqueous suspensions, and into dry mortar mixtures in the form of water-soluble powder or granules.

4.14.13 Water for mixing mortar mixtures and preparing additives is used in accordance with GOST 23732.

4.14.14 Bulk starting materials for mortar mixtures are dosed by weight, liquid components are dosed by weight or volume.

The dosing error should not exceed ±1% for binders, water and additives, and ±2% for aggregates.

For mortar mixing plants with a capacity of up to 5 m3/h, volumetric dosing of all materials is allowed with the same errors.

4.15 Labeling, packaging

4.15.1 Dry mortar mixtures are packaged in plastic film bags in accordance with GOST 10354 weighing up to 8 kg or paper bags in accordance with GOST 2226 weighing up to 50 kg.

4.15.2 Packaged dry mortar mixtures should be labeled on each package. The markings must be clearly marked on the packaging with indelible paint.

4.15.3 Mortar mixtures must have a quality document.

The manufacturer must accompany the dry mortar mixture with a label or marking applied to the packaging, and the ready-to-use mortar mixture dispensed into the vehicle with a quality document, which must contain the following data:

- name or trademark and address of the manufacturer;

- symbol of mortar according to 3.2;

- class of materials used to prepare the mixture, according to the specific effective activity of natural radionuclides and digital value;

- grade for compressive strength;

- mobility grade (P);

- volume of water required to prepare the mortar mixture, l/kg (for dry mortar mixtures);

- type and amount of added additive (% of binder mass);

- shelf life (for dry mortar mixtures), months;

- weight (for dry mortar mixtures), kg;

- quantity of mixture (for ready-to-use mortar mixtures), m;

- date of preparation;

- application temperature, °C;

- designation of this standard.

If necessary, the labeling and quality document may contain additional data.

The quality document must be signed by the manufacturer’s official responsible for technical control.

5 Acceptance rules

5.1 Mortar mixtures must be accepted by the manufacturer's technical control.

5.2 Mortar mixtures and solutions are accepted in batches through acceptance and periodic control.

A batch of mortar mixture and mortar is taken to be the quantity of a mixture of the same nominal composition with the same quality of its constituent materials, prepared using a single technology.

The volume of the batch is established by agreement with the consumer - no less than the output of one shift, but no more than the daily output of the mortar mixer.

5.3 All mortar mixtures and solutions are subject to acceptance control according to all standardized quality indicators.

5.4 When accepting each batch, at least five spot samples are taken from the mortar mixture.

5.4.1 Spot samples are taken at the place of preparation of the mortar mixture and/or at the place of its use from several batches or places in the container into which the mixture is loaded. Sampling points from the tank should be located at different depths. With a continuous supply of the solution mixture, point samples are taken at irregular intervals for 5-10 minutes.

5.4.2 After selection, spot samples are combined into a total sample, the mass of which must be sufficient to determine all controlled quality indicators of mortar mixtures and solutions. The selected sample is thoroughly mixed before testing (with the exception of mixtures containing air-entraining additives).

Mortar mixtures containing air-entraining, foaming and gas-forming additives are not additionally mixed before testing.

5.4.3 Testing of the mortar mixture, ready for use, should begin during the period when the normalized mobility is maintained.

5.5 The mobility and average density of the mortar mixture in each batch is monitored at least once per shift by the manufacturer after unloading the mixture from the mixer.

The humidity of dry mortar mixtures is controlled in each batch.

The strength of the solution is determined in each batch of the mixture.

Standardized technological indicators of the quality of mortar mixtures provided for in the supply contract (average density, temperature, delamination, water-holding capacity) and frost resistance of the solution are monitored within a time frame agreed with the consumer, but at least once every 6 months, as well as when the quality of the initial ones changes materials, composition of the solution and technology for its preparation.

5.6 Radiation-hygienic assessment of materials used for the preparation of mortar mixtures is carried out according to quality documents issued by enterprises that supply these materials.

In the absence of data on the content of natural radionuclides, the manufacturer determines the specific effective activity of natural radionuclides of materials in accordance with GOST 30108 once a year, as well as with each change of supplier.

5.7 Mortar mixtures, ready for use, are dispensed and taken by volume. The volume of the mortar mixture is determined by the output of the mortar mixer or by the volume of the transport or measuring container.

Dry mortar mixtures are released and taken by weight.

5.8 If, when checking the quality of the mortar, a discrepancy is revealed in at least one of the technical requirements of the standard, this batch of mortar is rejected.

5.9 The consumer has the right to carry out a control check of the quantity and quality of the mortar mixture in accordance with the requirements of this standard according to the methods of GOST 5802.

5.10 The manufacturer is obliged to inform the consumer, upon his request, the results of control tests no later than 3 days after their completion, and if the standardized indicator is not confirmed, notify the consumer immediately.

6 Control methods

6.1 Samples of mortar mixtures are taken in accordance with the requirements of 5.4, 5.4.1 and 5.4.2.

6.2 Materials for preparing mortar mixtures are tested in accordance with the requirements of standards and technical specifications for these materials.

6.3 The quality of chemical additives is determined by the effectiveness of their effect on the properties of mortars according to GOST 30459.

6.4 The concentration of the working solution of additives is determined with a hydrometer according to GOST 18481 in accordance with the requirements of standards and technical specifications for specific types of additives.

6.5 The specific effective activity of natural radionuclides in materials for the preparation of mortar mixtures is determined according to GOST 30108.

6.6 Mobility, average density, water-holding capacity and stratification of mortar mixtures are determined according to GOST 5802.

6.7 The volume of entrained air in mortar mixtures is determined according to GOST 10181.

6.8 The temperature of freshly prepared mortar mixtures is measured with a thermometer, immersing it in the mixture to a depth of at least 5 cm.

6.9 Compressive strength, frost resistance and average density of hardened solutions are determined according to GOST 5802.

6.10 The moisture content of dry mortar mixtures is determined according to GOST 8735.

7 Transportation and storage

7.1 Transportation

7.1.1 Mortar mixtures, ready for use, should be delivered to the consumer in vehicles, specially designed for their transportation.

With the consent of the consumer, transportation of mixtures in bunkers (tubs) is allowed.

7.1.2 The methods used for transporting mortar mixtures must exclude the loss of binder dough, the ingress of atmospheric precipitation and foreign impurities into the mixture.

7.1.3 Packaged dry mortar mixtures are transported by road, rail and other modes of transport in accordance with the rules for the transportation and securing of goods in force for this type of transport.

7.2 Storage

7.2.1 Delivered to construction site mortar mixtures, ready for use, must be reloaded into loader-mixers or other containers, provided that the specified properties of the mixtures are maintained.

7.2.2 Packaged dry mortar mixtures are stored in covered, dry rooms.

Bags of dry mixture must be stored at a temperature not lower than 5°C under conditions that ensure the safety of the packaging and protection from moisture.

7.2.3 The shelf life of the dry mortar mixture is 6 months from the date of preparation.

At the end of the storage period, the mixture must be checked for compliance with the requirements of this standard. If compliant, the mixture can be used for its intended purpose.

APPENDIX A (for reference). List of regulatory documents

APPENDIX A
(informative)

GOST 4.233-86 SPKP. Construction. Construction solutions. Nomenclature of indicators

GOST 125-79 Gypsum binders. Specifications

GOST 2226-2013 Bags made of paper and combined materials. General technical conditions

GOST 2642.5-2016 Refractories and refractory raw materials. Methods for determining iron (III) oxide

GOST 2642.11-97 Refractories and refractory raw materials. Methods for determining potassium and sodium oxides

GOST 3594.4-77 Molding clays. Methods for determining sulfur content

GOST 5578-94 Crushed stone and sand from ferrous and non-ferrous metallurgy slags for concrete. Specifications

GOST 5802-86 Construction mortars. Test methods

GOST 8735-88 Sand for construction work. Test methods

GOST 8736-2014 Sand for construction work. Specifications

GOST 9179-77 Construction lime. Specifications

GOST 10178-85 Portland cement and Portland slag cement. Specifications

GOST 10181-2014 Concrete mixtures. Test methods

GOST 10354-82 Polyethylene film. Specifications

GOST 18481-81 Hydrometers and glass cylinders. Specifications

GOST 21216-2014

GOST 21216-2014 Clay raw materials. Test methods

GOST 22266-2013 Sulfate-resistant cements. Specifications

GOST 23732-2011 Water for concrete and mortars. Specifications

GOST 24211-2008 Additives for concrete and mortars. General technical conditions

GOST 25328-82 Cement for mortars. Specifications

GOST 25592-91 Ash and slag mixtures from thermal power plants for concrete. Specifications

GOST 25818-2017 Fly ash from thermal power plants for concrete. Specifications

GOST 25820-2000 Lightweight concrete. Specifications

GOST 26633-2015 Heavy and fine-grained concrete. Specifications

GOST 26644-85 Crushed stone and sand from thermal power plant slag for concrete. Specifications

GOST 30108-94 Construction materials and products. Determination of specific effective activity of natural radionuclides

GOST 30459-2008 Additives for concrete. Methods for determining effectiveness

SNiP II-3-79* Construction heating engineering

APPENDIX B (recommended). Mobility of the mortar mixture at the site of application depending on the purpose of the solution

Table B.1

Main purpose of the solution	Cone immersion depth, cm	Mobility grade P
A Masonry:
For rubble masonry:
vibrated
unvibrated
For masonry made of hollow bricks or ceramic stones
For masonry made of solid bricks; ceramic stones; concrete stones or light rock stones
For filling voids in masonry and supplying with a mortar pump
For making a bed when installing walls made of large concrete blocks and panels; jointing horizontal and vertical joints in walls made of panels and large concrete blocks
B Facing:
For fastening slabs of natural stone And ceramic tiles on a finished brick wall
For fastening cladding products of lightweight concrete panels and blocks in the factory
In Plastering:
soil solution
spray solution:
with manual application
with a mechanized application method
coating solution:
without the use of gypsum
using gypsum

APPENDIX B (mandatory). Clay for mortars. Technical requirements

APPENDIX B
(required)

These technical requirements apply to clay intended for the preparation of mortars.

B.1 Technical requirements for clay

B.1.3 The content of chemical components by weight of dry clay should not be more than %:

- sulfates and sulfides in terms of - 1;

- sulfide sulfur in terms of - 0.3;

- mica - 3;

- soluble salts (causing efflorescence and efflorescence):

total iron oxides - 14;

the sum of potassium and sodium oxides is 7.

B.1.4 Clay should not contain organic impurities in quantities that impart a dark color.

B.2 Clay testing methods

B.2.1 The granulometric composition of clay is determined according to GOST 21216.2 and GOST 21216.12. B.2.4 The mica content is determined by the petrographic method according to

Operating conditions of enclosing structures, humidity conditions of premises according to SNiP II-3-79*

Minimum consumption of cement in masonry mortar per 1 m of dry sand, kg

Under dry and normal room conditions

In humid conditions

In wet room conditions

UDC 666.971.001.4:006.354	ISS 91.100.10
Key words: mortars, mineral binders, masonry, installation of building structures; masonry, facing, plastering mortars

Electronic document text

prepared by Kodeks JSC and verified against:
official publication
M.: Standartinform, 2018

Mortar combines the concepts of “mortar mixture”, “dry mortar mixture”, “mortar”.

Mortar is the name given to the material, obtained as a result of hardening of a mixture of binder (cement), fine aggregate (sand), binder (water) and, if necessary, special additives. This mixture before hardening begins is called a mortar mixture.

Dry mortar mixture- this is a mixture of dry components - binder, filler and additives, dosed and mixed at the factory - mixed with water before use.

The binder in the solution envelops the aggregate particles, reducing friction between them, as a result of which the mortar mixture acquires the mobility necessary for work. During the hardening process, the binder material firmly binds the individual aggregate particles together. Cement, clay, gypsum, lime or mixtures thereof are used as a binder, and sand is used as a filler. Construction mortars are classified depending on a number of factors: the binder used, the properties of the binder, the ratio between the amount of binder material and aggregate, density and purpose.

5.1.1. Classification of mortars by type of binder

Based on the type of binder used, mortars are:

- Simple - using one binder (cement, lime, gypsum, etc.);

- Complex - using mixed binders (cement-lime, lime-gypsum, lime-ash, etc.).

The compositions of simple solutions are designated by two numbers. The first number (usually one) shows that there is one volume (or mass) part of the binder material in the solution. The last number, in relation to the first, shows how many volumetric (or mass) parts of the filler are per part of the binder material. For example, a lime mortar with a composition of 1:3 means that in this solution there are 3 parts of aggregate for 1 part of lime. For complex solutions, the ratio consists of three numbers, of which the first number (unit) expresses the volumetric part of the main binder material, and the second number shows how much additional binder needs to be taken per part.

5.1.2. Classification of solutions depending on hardening conditions

Depending on the hardening conditions, the following solutions exist:

- Air solutions - hardening in air-dry conditions (for example, gypsum);

- Hydraulic - those that begin to harden in air and continue to harden in water or in humid conditions (cement).

5.1.3. Classification of solutions depending on the quantitative ratio of components

Depending on the ratio between the amount of binder material and filler, the following are distinguished:

- Fatty solutions - solutions with excess binder material. Their mixtures are very plastic, but during hardening they shrink greatly; fatty solutions applied in a thick layer crack;

- Normal solutions;

- Lean solutions - contain a relatively small amount of binder material. However, they give very little shrinkage, which is very valuable for facing work.

5.1.4. Classification of solutions depending on density

Based on density, mortars are divided into:

- Heavy - with an average dry density of 1500 kg/m 3 or more, prepared on ordinary sand;

- Lungs - with an average density of up to 1500 kg/m3, which are prepared on light porous sand from pumice, tuff, expanded clay, etc.

5.1.5. Classification of solutions by purpose

According to their intended purpose, mortars are:

- Masonry (for regular and fire-resistant stone masonry, installation of walls from large-sized elements);

- Finishing (for plastering rooms, applying decorative layers to wall blocks and panels);

- Special (having special properties - waterproofing, acoustic, X-ray protective).

5.2. General properties of mortars

Portland cement, Portland slag cement, special low-grade cements, lime, gypsum, mixed binders, as well as binders with mineral additives are used as binders for the preparation of mortars.

Lime in mortars is used in the form of lime paste or milk. Gypsum is used in plaster mortars as an additive to lime;

Natural quartz sands, as well as sands obtained by crushing dense rocks, serve as fine aggregates for heavy solutions; for light solutions - sands made of pumice, slag, expanded clay, tuff and shell rock. The size of sand grains should not exceed 2.5 mm, and the content of clay, silt and dust particles in the sand, the amount of which is determined by elutriation, should not exceed 10% by weight.

To improve the plastic properties of the solution, plasticizing additives are introduced into its composition in the form of clay milk, sulfate-yeast mash, and soap naft. Tripod, volcanic ash, etc. are used as hydraulic additives.

Properties . The most important properties of mortars are strength, frost resistance, mobility and water-holding capacity of mortar mixtures.

Mortar mixtures characterized by workability, mobility and water-holding capacity. Workability is the ability of a mortar mixture to be easily distributed in an even, thin layer on a brick or other base; it is determined by the mobility of the mixture, its non-separability and water-holding capacity. The mobility of the mortar mixture is characterized by the depth of immersion of a metal standard cone into it in centimeters, weighing 300 g, height 145 mm and base diameter 75 mm (apex angle 30°) and is determined on a standard device. The mobility of the mortar mixture, depending on the purpose of the solution, is assumed to be:

For ordinary rubble masonry - 4-6 cm and for vibrated rubble masonry - 1-3 cm;

For filling and jointing joints in walls made of concrete and brick panels and large blocks - 5-7 cm; for ordinary masonry made of hollow bricks or ceramic stones - 7-8 cm;

For ordinary masonry made of ordinary bricks, concrete stones and stones made of light rocks (tuff, etc.) -9-13 cm, for plaster mortars - 7-12 cm.

The property of a mortar mixture not to separate during transportation and not to lose mobility when laid on a porous base depends on its water holding capacity . The low water-holding capacity of the mortar mixture can lead to its separation during transportation. Water-holding capacity is also important for the normal hardening of the mortar mixture. When a mortar mixture with low water-holding capacity is laid on a porous substrate, water is easily absorbed by the substrate, causing a sharp increase in the hardness of the mixture. Rigid mortar mixtures cannot be evenly distributed over the base and do not adhere well to it.

The water-holding capacity of the mortar mixture increases with increasing cement content, replacing part of the cement with lime, and also with the introduction of highly dispersed additives - ashes, clays and some surfactants (soap, saponified wood pitch, etc.). In addition, the introduction of highly dispersed plasticizing additives into the mortar mixture allows saving cement, lime and other binders. Reducing the consumption of binders by introducing plasticizing additives provides a significant economic effect, since masonry and plaster mortars are one of the most widely used building materials. Solutions with the specified plasticizing additives adhere well to the surface being treated, have uniform deformations after hardening and sufficiently high strength.

The compressive strength of the mortar, deformability, adhesion to the base and frost resistance are the main indicators of the quality of the mortar.

Mortar strength during compression is determined by the activity of the binder, the water-binder ratio, age and hardening conditions. However, taking into account that in solutions of the same composition, but with different water content, approximately the same amount of water remains after laying on a porous base.

Strength of mortars is usually significantly lower than the strength of concrete. Most mortars are not required to have high mechanical strength, since the mortar does not significantly affect the strength of stone masonry of the correct shape, and plaster mortars practically do not bear any load. The strength of the solution is characterized by the grade, i.e., the rounded compressive strength of samples (in the form of cubes with an edge of 7.07 cm), prepared from a solution of working consistency, hardening on a porous base at a temperature of 15 - 25 ° C and tested at 28 - day age. Based on strength from 0.4 to 30 MPa, the following grades are established for solutions: 4, 10, 25, 75, 100, 150, 300;

The strength of mortars, as well as concrete, depends mainly on the activity of the binder and water-binder ratio. To predict the strength of cement-lime mortars, the formulas of N.A. Popov are widely used. When laid on a dense base, the strength of the mortars (R p) is calculated using the formula:

R p = 0.25*R c *(C/V – 0.4) (1)

where R c is the activity of cement; C/W - cement-water ratio.

When water is sucked out by a porous base, approximately the same amount of water remains in solutions with different C/V, and the strength is expressed depending on the consumption of the binder:

R p = k*R c *(C/V – 0.05) + 4 (2)

where k is the sand quality factor: for coarse sand k = 2.2, medium-sized sand k = 1.8, fine sand k = 1.4.

To predict strength cement mortars laid on a dense base, you can apply the formula proposed for fine-grained concrete:

R p = A*R c *(C/V – 0.8) (3)

where A is a coefficient equal to 0.8 for high-quality materials, 0.75 for medium-quality materials and 0.65 for low-grade cement and fine sand.

According to frost resistance, solutions are divided into the following grades: F 15, 25, 35, 50, 100, 150, 200 and 300. To obtain a mortar of a given grade, it is necessary to select the optimal ratios between the constituent materials - binder, sand and water. The selection of the optimal composition of the mortar and the calculation of the amount of starting materials are carried out using various methods that provide a given grade of mortar at a certain mobility. These methods are based on the above dependence of the strength of the solution on various factors. The compositions of solutions of low grades (up to 25) are usually selected according to the tables available in the instructions.

Construction mortars are thoroughly mixed mixtures of binders (cement), fine aggregates (sand), aggregates (water) and, if necessary, special additives. After hardening it turns out fake diamond. In practice, this is fine-grained concrete, without the addition of coarse and medium-sized aggregates.

Classification of building mortars

Solutions are classified according to the following criteria:

1. According to the binders used:
   • cement, on Portland cement or its varieties;
   • lime, lime, air and hydraulic;
   • gypsum, in which the binder is gypsum.

   Simple solutions use one type of binder. In complex mixtures (for example, lime-cement or lime-gypsum).

   The specific binder is selected depending on the purpose of the solutions, the environmental conditions in terms of humidity and temperature at which hardening occurs, and the conditions in which the building structure is expected to be used.

2. According to the main use of mortars, they are distinguished:
   • masonry, including those used in laying large building elements and during installation work;
   • facing, for the design of various architectural products;
   • plastering machines for plastering buildings inside and outside with decorative layers;
   • for special purposes, with pronounced special properties (for example, plugging, injection or acoustic). Such mortars are intended for narrow, specific applications.
3. According to average density in dry form there are:
   • heavy, volumetric mass ≥ 1500 kg/m3, prepared using quartz sands;
   • light, with a density ≤ 1500 kg/m3. Ground porous materials (tuff, expanded clay, pumice and blast furnace slag) are used as filler. This type also includes porous solutions prepared with foaming agents.

Types of mortars

According to the ratio of the amount of binding materials and fillers, they differ:

• fatty mortar materials characterized by an excess of binders. They are distinguished by their plasticity and ease of use, but have a high degree of shrinkage during hardening. When applied in a thick layer, cracks appear;
• skinny, with little astringent content. They are characterized by low shrinkage, which is especially important when performing facing work;
• normal.

An important characteristic is the strength of the solution. Grades of mortars by strength, meaning compressive strength, are divided into grades from 4 to 200 tons.

Brand strength, depending on the degree of activity of the binder, the water-cement ratio and the quality of fine aggregates, is determined in the laboratory by compressing samples in the form of cubes of certain sizes after 28 days of hardening at temperatures from 15 to 25 degrees. If hardening occurs in a different temperature range, then the relative grade is determined using special tables. Samples with a mixture mobility of ≤ 5 cm are made in collapsible metal forms with a bottom, and with greater mobility in forms on a brick or other solid base.

Relative average strength of cement mortar mixtures hardening in the above temperature conditions, is the following values ​​in fractions of brand strength:

• at 3 days of age - 0.25;
• 7 days - 0.5;
• after 14 - 0.75;
• 60 - 1.2;
• after 90 - 1.3.

In mixed mortar mixtures greatest strength with optimal workability, it is achieved by introducing finely ground additives into them.

When using mortar mixtures in winter conditions their grade is increased by one step (for example, instead of 100, 150 is used) and additives that slow down the freezing of water and accelerate hardening (potash, sodium and calcium chloride, sodium nitrate and others). To mix the mixture, water without harmful impurities is used, usually tap water is used.

Another important characteristic is frost resistance, characterized by the number of cycles of alternating freezing and thawing that can be withstood. The state standard for frost resistance of construction mortars stipulates 9 grades, from F10 to F300. Tests are carried out in the laboratory with alternate freezing and thawing of water-saturated samples in the form of cubes with 15 cm sides until the initial strength is reduced to 15%. If used in a humid environment, the grade must be upgraded.

When preparing mortar mixtures, it is important to maintain the optimal water-cement ratio.

For finishing the front surfaces of large-block structures and panels in factories, plastering inside and outside buildings, finishing architectural elements decorative colored solutions are used. Binders are white and colored Portland cement, gypsum and lime. Aggregates - quartz washed sands or obtained by crushing multi-colored rocks (granite, limestone, marble, tuff, dolomite). Mica ≤ 1% or crushed glass up to 10% are added to the mixture. For coloring we use natural (ocher, red lead, mumiyo, chromium oxides, ultramarine) and artificial dyes that have chemical and light resistance.

The following are added to construction mortar mixtures as additives:

• organic and minerals, increasing workability. It is effective to add lime paste to cement mixtures, which saves cement, increases the ability to retain water, which is of great importance during transportation, and improves the ease of installation. Mineral supplements with high activity (diatomaceous earth, slag powders, tripoli, etc.) are introduced in dispersed form;
• surfactants, which increase plasticity and save binders, are added in hundredths of a percentage of the mass of binders. The most commonly used are SDB and soap naft. Preparation, storage of constituent substances, transportation and use ready-made mixtures regulated by GOST 28013-98.

Mortars- these are mixtures of binder, water and fine aggregate, acquiring a stone-like structure as a result of the hardening process. Before hardening, they are called mortar mixtures and are used for masonry walls, foundations, and plastering the surfaces of various structures.
Based on the type of binders and additives, they are distinguished cement mortars, limestone, cement-lime, cement-clay and etc.
Based on the properties of the binder, solutions are divided on air, manufactured with air binders ( lime, plaster), And hydraulic- with hydraulic binders ( cement various types).
According to the type of fillers, they are distinguished heavy solutions- with natural sands and lungs with porous fillers.
The composition of the solutions is simple- with one binder(cement, lime) and mixed, which usually include two, less often three binders, or one binder with inorganic additive ( cement-lime, lime-clay and etc.).
Air mortars used for the construction of stone structures, operated in a dry environment, and hydraulic- in wet conditions.
Heavy solutions, where the filler is quartz sand, have a volumetric mass of more than 1600 kg/m3; lungs- less than 1500 kg/m3, the filler is sand made from expanded clay, ground slag, etc.
Strength solution determined by its brand (the numbers indicate compressive strength in kgf/cm2).
Waterproof solutions used to make structures waterproof (for example, cement mortar composition 1:2 with the addition of liquid glass, etc.).

Composition of the solution

To prepare solutions use binding materials, fillers and additives.
TO binders includes puffed lime in the form of dough, fluff and quicklime; building gypsum, Portland cement and etc.
The filler for mortar mixtures is natural or artificial sand.

Air lime

Air lime It hardens only in air, which is why it is called air. She may be a quicklime lump ( lime-boiler), ground and slaked into powder ( fluff lime).
Quicklime- these are pieces of grayish color; ground- fine grayish powder.
Lime extinguished in an extinguishing box or barrel. In large quantities slaked lime stored in a creative pit dug in the ground and lined with boards. More often lime used as a test or fluff lime.

Construction gypsum

Construction gypsum It is rarely used in mortars, mainly for work in dry conditions, but as an additive to lime plaster mortars in large quantities. In lime mortars gypsum increases strength, reduces setting and hardening time.

Gypsum

Gypsum- This is a white or grayish finely ground powder. Sealed with water gypsum depending on the purpose, the beginning of setting is 2-20 minutes, the end of setting is 15-30 minutes or more. If necessary, you can extend the setting time gypsum, adding a retarder to it. As the latter, 5-20% lime paste, 5-10% borax, 0.5-2% flesh glue by weight are added to the mixing water gypsum. These additives help extend the setting time gypsum up to 40-60 min.

Portland cement

Portland cement is the most durable binding material. It has the following grades: 200, 300, 400 (the numbers indicate compressive strength in kgf/cm2). Portland cement is a grayish-green finely ground powder.
Grasping cement As a rule, it begins no earlier than 45 minutes and ends no later than 12 hours after mixing with water.
It must be taken into account that during storage cement its activity is falling by about 5% per month. Based on this, you should purchase freshly made, not stale cement. Its quality is determined visually by the sign of pelletization, by touch: if a handful cement clench in a fist, then freshly made cement it immediately wakes up between the fingers, and the stale one forms a lump, since it has already absorbed moisture. Until the lump can still be kneaded with your fingers, cement is considered suitable for consumption, but its dosage is usually increased by 20-50%.

Filler sands

Filler sands There are natural (heavy) ones - quartz, feldspathic or artificial.
The coarseness of the sand should correspond to the thickness of the seam and the nature of the masonry; Thus, for rubble masonry, sand with grains no larger than 5 mm is used, for brick masonry - no larger than 3 mm.
The grain size of the sand is approximately determined by touch. The grain size of coarse sand is more than 2.5 mm; medium - from 2 to 2.5 mm, small - less than 1.5 mm.
IN mortars fillers usually occupy 60-65% of the volume.
The permissible contamination of sand with clay and dust for solutions of grades 25 and 50 is no more than 10%, for a solution of grade 10 - up to 15%. If necessary sand washed.
As lungs fillers shell sands, granulated boiler and blast furnace slags, expanded clay are used sand.
Depending on density artificial sand divided into grades according to bulk density from 250 to 1100 (the numbers indicate the bulk density of sand, kg/m3).

Clay

It is introduced into lime and cement mortars as an additive in such quantities that the ratio cement : clay did not exceed 1:1 (by volume). The addition of clay improves the grain composition, increases water-holding capacity, improves workability, and increases the density of the solution.
Clay consists of different minerals, so it comes in different colors.
Distinguish skinny, medium and fat clay. Skinny is usually used in its pure form, medium in fat and fat is added to solution in smaller quantities.

Preparation of masonry mortars

Masonry mortar can be prepared in a concrete mixer with a capacity of 0.15 m3 or manually.
The cement mortar is prepared as follows: in a metal or wooden box made of boards 25-30 mm thick with a bottom covered with roofing iron, dimensions 1 x 0.5 m or 1.5 x 0.7 m, height 0.2-0.25 m, first fill in the required number of buckets of sand pour a full bucket of cement on top in an even layer, then shovel the mixture until the mixture is uniform in color, then pour a measured amount of water from a watering can and continue shoveling until a homogeneous composition is obtained.
Cooked solution spend within 1.5 hours so that it does not lose strength. Sand For preparing the solution must first be sifted through a sieve with 10x10 mm cells ( for masonry).

The lime paste solution is prepared immediately, mixing it with sand and water until smooth.

Cement-lime mortar prepared from cement, lime paste and sand.

Lime dough diluted with water until milk is thick and filtered on a sieve with 10x10 mm cells. A dry mixture is prepared from cement and sand and mixed with lime milk to the required thickness (dough consistency).

Cement-clay mortar prepared similarly to cement-lime.

Compositions(in volumetric parts) cement, cement-lime, limestone And brands of solutions shown in table 12.

Table 1. Compositions of cement-lime, cement-clay and cement mortars for stone structures

Brand cement	Volumetric dosage (cement: lime or clay: sand) for mortar grades
	150	100	75	50	25	10
400	1: 0,2: 3 1: 0: 3	1: 0,4: 4,5 1: 0: 4,5	1: 0,5: 5,5 1: 0: 5,5	1: 0,9: 8	---	---
300	1: 0,1: 2,5 1: 0: 2,5	1: 0,2: 3,5 1: 0: 3	1: 0,3: 0,4 1: 0: 4	1: 0,6: 6 1: 0: 6	1: 1: 10,5 1: 1: 9	---
200	---	---	1: 0,1: 2,5 1: 0: 2,5	1: 0,3: 4 1: 0: 4	1: 0,8: 7 ---	1: 1: 9 1: 0,8: 7

Note:
Upper values ​​for cement-lime mortars, lower - cement-clay mortars. 0 - indicates the absence of this binder in the solution.

Table 2. Compositions of lime mortars

Requirement of cement per 1 cubic meter. sand or cement-lime or cement-clay mortar is given in table 3.

Table 3. Cement consumption, kg per 1 m³ of sand (mortar)

Cement brand	Brand of solution
	150	100	75	50	25	10
400 200	350 400	255 300	200 240 405 445	140 175 280 325	--- 155 190	--- 75 95

Note: Numerator - cement consumption per 1 cubic meter. sand. Denominator - 1 cubic meter. solution.