Composition, proportions and use of cement-lime mortar. Ready-made finishing heavy lime mortar: properties and characteristics Heavy lime mortar 1 2.5

In the process repair work with my own hands, I have come across the production of plaster more than once. Everyone knows that it is used to carry out preparatory work, when it is necessary to patch cracks and level out existing unevenness for further finishing. In addition, plaster can be used as finishing for external insulation of a house using polystyrene foam. Today I want to talk about mortar, its composition and preparation with your own hands.

Slaked lime

Binding fillers

Before making a solution, you need to know not only its specifications, but also the proportions with which you knead with your own hands. Since additives are astringent and are used to strengthen the finished coating, I will start with them:

1. Gypsum - it is used to make a lime-gypsum mortar, which is perfect for plastering stone or wooden surfaces. When mixing it, it is important not to make a large number of material, since it must be used very quickly. average speed hardening time for this mixture is 10 minutes
2. Cement - due to the fact that it is in solution, it becomes possible to use plaster for external processes or in rooms with increased level humidity. Cement-lime mortar is perfect for renovation work inside and outside the house
3. Clay - very rarely used together with lime; the use of a solution on such a basis is necessary to strengthen the previous layers, which consist of natural clay
4. Sand - this composition is the most common. If some river sand is present in the solution, it should be washed before use. Quarry sand in this case it is sifted

By the way, in addition to the above components, lime mortar may contain various catalysts or plasticizers that accelerate the hardening process. I'll talk about the latter a little later.

Benefits of lime mixture

Preparing lime mortar

Before I started working with lime mortar, I decided to learn about all its advantages and pitfalls. Therefore, by the time I prepared it with my own hands, I was completely armed. Let's look at the advantages of this material:

• The elasticity of the material simplifies the work process, and the plaster has fire-resistant properties
• Environmentally friendly, while covered wooden surfaces and the walls will be protected from rodents and insects
• No signs of mold or mildew
• If several layers are applied, they are firmly adhered to each other
• Microcracks do not appear

Lime mortar has few disadvantages, the most important of which is the long drying process, which is significantly inferior to cement and sand plaster. In addition, the material may begin to float - in order to get rid of this defect, you should wait until the first layer is completely dry and only then begin applying subsequent ones.

Important! When making lime mortar, you choose the composition based on the required goals. Also, for lime mortar, the proportions must be observed depending on the components of the future plaster.

Preparation

Lime mortar

Preparation

Lime mortar

The composition of lime mortar is lime and sand, the proportions of which can be 1:2, 1:3, 1:4 and 1:5. It is the concentration of lime that influences these proportions, and if the mixture turns out to be too greasy, then the required amount of sand is gradually added. If, on the contrary, the mixture is too liquid, then you should add lime.

Important! To prepare the solution, it is necessary to use slaked lime.

The first step is to get the lime dough. To do this, take a container, it is important that it is not plastic or metal, and pour the dry mixture into it, then fill it with heated water. Next, the container should be tightly closed, otherwise during the reaction, everything will fly apart. different sides. At the end of boiling, 2 liquids will form - the white one will need to be drained, and the thick one will be left for a day for further thickening. Sifting of sand occurs using a sieve with cells of 3*3 or 5*5 mm. Sand and water are added to the existing dough in portions and mixed well. As a result, we get a lime mass that has normal fat content and the consistency necessary for work.

Cement mortar

DIY lime mortar

Masonry cement mortar is especially popular for DIY preparation. If you need to figure out the proportions, then you should pay attention to the markings - this is the ratio of sand and cement. Let's look at everything more clearly using a small table as an example:

Strength grade	Proportions of ingredients in the composition			Compressive strength MPa
	Cement	Lime	Sand
M-50	1	0,5	4,5-4	5
M-75	1	0,32	4	8
M-100	1	0-0,25	3-3,5	10
M-150	1	0	1,5-2	12,8
M-200	1	0	1-1,1	15

Let's take a little closer look at each brand:

• M-50 - consists of lime and cement, used for low-rise buildings, as it does not have high strength properties. Ready-made masonry mortar is most often used for grouting uneven surfaces
• M-75 – suitable for internal masonry work, as well as for plastering leveling processes
• Mixture grade 100 is one of the most popular mixtures, as it can be used both in external work and for internal processes. If a plasticizer is added to the composition, the material can be used for plastering external walls.
• M-150 is a sought-after mixture that is used for complex construction, that is, for multi-story buildings. Grade 150 is used in floor screeding processes and also for foundations. M-150 is resistant to low temperatures
• M-200 - masonry with such a solution can withstand high temperatures. The material is heat resistant and does not get wet

A little about plasticizers

Making your own lime mortar

For those who have not yet encountered plasticizers, you should immediately remember what it is used for. A plasticizer is necessary for cement mortar or concrete in order to increase their fluidity and ductility. Ultimately, improving such indicators leads to an increase in the strength of the already hardened coating.

If you decide to add a plasticizer to your solution, you should know that the dosage may vary for each manufacturer. The average percentage is 0.5-1%; if converted to kilograms, then per 100 kg of cement it is necessary to add from 0.5 to 1 kg of plasticizer.

installation -for filling and sealing seams between large elements during the installation of buildings and structures from ready-made prefabricated structures and parts;

special -waterproof, acid-proof, heat-resistant, acoustic, heat-insulating, injection, X-ray-proof and pipe-pumpable.

The mortars do not contain coarse aggregate, so they are essentially fine-grained concrete. General laws characterizing the properties of concrete are, in principle, applicable to mortars. However, when using solutions, two features must be taken into account. Firstly, they are laid in thin layers (1...2 cm), without using mechanical compaction. Secondly, solutions are often applied to porous substrates (brick, concrete, lightweight stones and porous rock blocks), which can strongly absorb water. As a result, the properties of the solution change, which must be taken into account when determining its composition.

Selection of composition, preparation and transportation of solutions

Compositions mortar mixtures are chosen or selected depending on the purpose of the solution, the required grade and mobility and the conditions of work. The selected composition of mortar mixtures must have the necessary mobility (without separation and water separation during installation) when minimum consumption binder and ensure that the required strength is obtained in the hardened state.

The compositions of mortars are selected according to tables and by calculation, in both cases they are clarified experimentally in relation to specific materials.

The computational and experimental method for selecting the composition of a solution is based on a preliminary calculation of the consumption of components (binder, fillers, water and additives) based on scientifically based and experimentally verified dependencies given below. It is used to select the composition of heavy masonry and installation mortars.

The composition of solutions of grades 25...200 is selected as follows.To obtain a given grade of mortar in the case of using binders that differ in grade M vf from those given in 5.8 (table 4 ) SP 82-101-98 Preparation and use of construction mortars, the consumption of binder per 1 m 3 of sand is determined byformula

Where Q c - consumption of binder with activity according to the table 4 per 1 m 3 sand, kg;

Q vf — consumption of binder with other activity;

R V Q V - accepted according to the table 4 for a given brand of solution.

Amount of inorganic plasticizers (lime or clay dough) V d per 1 m 3 of sand is determined by the formula

V d = 0,17(1 — 0,002Q in),

Where V d - inorganic additive per 1 m 3 of sand, m.

Calculation of the composition of the solution should be preceded by determination of the activity (grade) and average bulk density of cement, grain composition and fineness modulus of sand, average density of inorganic plasticizer (lime or clay).

Preparation of solutions. Solutions are available in the form of ready-to-use or dry mixtures, mixed with water before use.

The process of preparing a mortar mixture consists of dosing the starting materials, loading them into the drum of the mortar mixer and mixing until a homogeneous mass is obtained in batch mortar mixers with forced mixing. By design, mortar mixers are distinguished with a horizontal or vertical blade shaft. The latter are called turbulent mixers.

Mortar mixers with a horizontal blade shaft are produced with a finished batch capacity of 30; 65; 80; 250 and 900 l. All of these mixers, with the exception of the last one, are mobile. Capacity for the finished batch of turbulent mixers, the working body of which is fast-rotating rotors - 65; 500 and 800 l.

In order for the solution to have the required properties, it is necessary to achieve uniformity of its composition. To do this, limit the minimum mixing time. The average duration of the mixing cycle for heavy solutions should be at least 3 minutes. Light solutions take longer to mix. To facilitate this process, lime and clay are introduced into the solution in the form of lime or clay milk. Lime paste and lump clay cannot be used for mixed mortars, since in this case it is almost impossible to achieve uniformity of the mortar mixture.

For cooking cement mortars with inorganic plasticizers, lime (clay) milk is poured into a mortar mixer of such a consistency that there is no need to add additional water, and then filler and cement are poured. Organic plasticizers are first mixed in a mortar mixer with water for 30...45 s, and then the remaining components are loaded. Mortars, as a rule, are prepared at centralized concrete mortar plants or mortar units, which ensures the production of High Quality. In winter, to obtain solutions with a positive temperature, the components of the solution - sand and water - are heated to a temperature of no more than 60 ° C. The astringent cannot be heated.

Transportation. Mortar mixtures from factories are transported by dump trucks or specially equipped transport, which eliminates the loss of cement laitance, environmental pollution, moisture from precipitation, and a decrease in temperature. The transportation distance depends on the type of solution, road condition and air temperature. To protect the solution from hypothermia and freezing in winter, car bodies are insulated or heated with engine exhaust gases.

At construction sites, the mortar mixture is supplied to the place of use through pipes using mortar pumps.

The shelf life of mortar mixtures depends on the type of binder and is limited by its setting time. Lime mortars retain their properties for a long time (until the water evaporates from them), and water can be added to the dried lime mortar and mixed again. Cement mortars must be used within 2…4 hours; dilution with water and repeated mixing of hardened cement mortars is not allowed, as this leads to a sharp decrease in its quality, i.e., a drop in the grade of the mortar.

Mortars for laying foundations and plinths below the waterproofing layer

Cement brand	Soil type
	Low moisture		Wet	Saturated with water
	Cement-lime mortar M10 (cement: lime paste: sand)	Cement-clay mortar M25 (cement: clay dough: sand)	Cement-lime and cement-clay mortar M25 (cement: lime or clay: sand)	Cement mortar M50 (cement: sand)
50	1:0,1:2,5	1:0,1:2,5	—	—
100	1:0,5:5	1:0,5:5	1:0,1:2	—
150	1:1,2:9	1:1,7	1:03:3,5	—
200	1:1,7:12	1:1:8	1:0,5:5	1:2,5
250	1:1,7:12	1:1:9	1:0,7:5	1:3
300	1:2,1:15	1:1:11	1:0,7:8	1:6

Note: The compositions of solutions are given in volumetric ratios. Sand is accepted as medium coarse with a moisture content of 2% or more. When using dry sand, its dosage is reduced by 10%.

The cement mortar is prepared in this way: first prepare a dry mixture, which is then mixed with water and mixed. Dry cement mortars are mixed with water, mixed and used for 1-1.5 hours. Water is also carefully dosed. Excess water will result in a thinner solution; after drying, it becomes less durable than a thick solution of the same composition.

Cement-lime mortar is prepared in proportions. These are so-called complex solutions designed to work under normal conditions. Therefore, such solutions should not be used for masonry located below the groundwater level. Cement-lime mortars are most often used for interior masonry or plastering. basements. It is prepared in this order.

Lime dough is diluted to the consistency of milk and filtered on a clean sieve. A dry mixture is prepared from cement and sand, mixed with lime milk and thoroughly mixed until a homogeneous mass is obtained. The addition of lime milk increases the plasticity of the solution and makes it “warmer” (Tables 2, 3).

Composition of mortar for above-ground masonry with room humidity less than 60%

Cement brand	Brand of solution
	100	75	50	25
600	1:0,4:4,5	1:0,7:6	—	—
500	1:0,3:4	1:0,5:5	1:1:8	—
400	1:0,2:3	1:0,3:4		1:1,7:1,2
300	—	1:0,2:3	1:0,4:4,5	1:1,2:9
Cement-clay mortars
600	1:0,4:4,5	1:0,7:6	—	—
500	1:0,4:4,5	1:0,7:6	1:1:3	—
400	1:0,2:3	1:0,3:4	1:0,7:6	1:1:11
300	—	1:0,2:3	1:0,4:4,5	1:1:9

Table 3. Composition of mortar for above-ground masonry with room humidity more than 60%

Cement brand	Brand of solution
	100	75	50	25
Cement-lime mortars
600	1:0,4:4,5	1:0,7:6	—	—
500	1:0,3:4	1:0,5:5	1:0,7:8	—
400	1:0,2:3	1:0.3:4	1:0,7:6	—
300	—	1:0,2:3	1:0,4:4,5	1:0,7:9
Cement-clay mortars
600	1:0.4:4,5	1:0,7:6	—	—
500	1:0,3:4	1:0,5:5	1:0,7:6	1:0,7:8,5
400	1:0,2:3	1:0,3:4	1:0,7:6	1:0,7:8,5
300	—	1:0,2:3	1:0,4:5	—
Cement mortars
600	1:4,5	1:6	—	—
500	1:4	1:5	—	—
400	1:3	1:4	1:6	—
300	—	1:3	1:4,5	—

Lime mortar is prepared by mixing clean sand with lime milk without the inclusion of cement. Typically these are low grade mortars and are mostly used for interior plastering of residential premises. Such solutions are characterized by ease of application, good adhesion to masonry material. Lime mortars harden slowly and to speed up this process, gypsum is often added to the solution. The need to introduce gypsum especially increases when plastering ceilings and slopes, where increased demands are placed on the speed of hardening of the solution.

To obtain a clay-lime mortar, clay and lime are mixed and then filled with water. The resulting mixture is mixed with sand in the required proportion. Such solutions are used in summer conditions for above-ground masonry, mainly in dry climates with normal indoor air humidity.

Compositions of cement-lime, cement-clay and cement mortars
Brand solution	Compositions in volumetric dosage of solutions depending on the brand of binder
	500	400	300	200	150
Compositions of cement-lime and cement-clay mortars for above-ground structures at a relative indoor air humidity of up to 60% and for foundations in low-moisture soils
300	1: 0,15: 2,1	1: 0,07: 1,8
200	1: 0,2: 3	1: 0,1: 2,5
150	1: 0,3: 4	1: 0,2: 3	1: 0,1: 2,5
100	1: 0,5: 5,5	1: 0,4: 4,5	1: 0,2: 3,5
75	1: 0,8: 7	1: 0,5: 5,5	1: 0,3: 4	1: 0,1: 2,5
50		1: 0,9: 8	1: 0,6: 6	1: 0,3: 4
25			1: 1,4: 10,5	1: 0,8: 7	1: 0,3: 4
10					1: 1,2: 9,5
Compositions of cement-lime and cement-clay mortars for above-ground structures with a relative humidity of indoor air above 60% and for foundations in wet soils
300	1: 0,15: 2,1	1: 0,07: 1,8
200	1: 0,2: 3	1: 0,1: 2,5
150	1: 0,3: 4	1: 0,2: 3	1: 0,1: 2,5
100	1: 0,5: 5,5	1: 0,4: 4,5	1: 0,2: 3,5
75	1: 0,8: 7	1: 0,5: 5,5	1: 0,3: 4	1: 0,1: 2,5
50		1: 0,9: 8	1: 0,6: 6	1: 0,3: 4
25			1: 1: 10,5 / 1: 1: 9*	1: 0,8: 7	1: 0,3: 4
10					1: 1: 9 / 1: 0,8: 7*
Compositions of cement mortars for foundations and other structures located in water-saturated soils and below the groundwater level
300	1: 0: 2,1	1: 0: 1,8
200	1: 0: 3	1: 0: 2,5
150	1: 0: 4	1: 0: 3	1: 0: 2,5
100	1: 0: 5,5	1: 0: 4,5	1: 0: 3,0
75	1: 0: 6	1: 0: 5,5	1: 0: 4	1: 0: 2,5
50			1: 0: 6	1: 0: 4
* Above the line - compositions of cement-lime mortars, below the line - cement-clay mortars. Cement: Lime (Clay): Sand. Sand is accepted according to GOST 8736

Selection of binders when preparing masonry mortars
Operating conditions of structures	Type of binder
1 For above-ground structures with a relative indoor air humidity of up to 60% and for foundations erected in low-moisture soils	Portland cement, plasticized and hydrophobic Portland cement, slag Portland cement, pozzolanic Portland cement, mortar cement, lime slag binder
2 For above-ground structures with a relative humidity of indoor air above 60% and for foundations erected in wet soils	Pozzolanic Portland cement, plasticized and hydrophobic Portland cement, slag Portland cement, Portland cement, mortar cement, lime-slag binder
3 For foundations with aggressive sulfate waters	Sulfate-resistant Portland cements, pozzolanic Portland cement

Approximate costs of binder per 1 m³ of sand or per 1 m³ of solution
Knitting	Solution brand Mр	Binder grade MV	Binder consumption, kg
			per 1 m³ of sand	per 1 m³ of solution
GOST 10178 GOST 25328 GOST 22266
The consumption of binders is indicated for mixed cement-lime and cement-clay mortars and sand in a loosely poured state at a natural humidity of 3–7%.

Plastering solutions and for fastening facing tiles

Type and composition of the solution for preparatory layers of external and internal plasters (spray and primer)
Type of surface to be plastered	Type and composition of the solution
	cement	cement-lime	limestone	lime-gypsum
For spraying
Stone and concrete	from 1: 2.5 up to 1:4	from 1:0.3:3 up to 1:0.5:5
For soil
Stone and concrete	from 1:2 up to 1:3	from 1: 0.7: 2.5 up to 1:1,2:4>
External plaster of walls not subject to systematic moisture, and interior plaster in rooms with relative humidity air up to 60%
For spraying
		from 1:0.5:4 up to 1:0.7:6	from 1: 2.5 up to 1:4	from 1:0.3:2 up to 1:1:3
For soil
Stone and concrete. Wooden and plaster		from 1:0.7:3 up to 1:1:5	from 1:2 up to 1:3	from 1: 0.5: 1.5 up to 1:1.5:2

Type and composition of the solution for the finishing layer (coating) of external and internal plasters
Type of soil for plastered surfaces	Type and composition of the solution
	cement	cement-lime	limestone	lime-gypsum
External plaster of walls, plinths, cornices, etc., subject to systematic moisture, as well as internal plaster in rooms with relative air humidity above 60%
	from 1:1 up to 1:1.5	from 1:1:1.5 up to 1:1.5:2
External plaster of walls not subject to systematic moisture, and internal plaster in rooms with relative humidity up to 60%
Cement and cement-lime		from 1:1:2 up to 1:1.5:3
Lime and lime-gypsum			from 1:1 up to 1:2	from 1:1:0 up to 1:1.5:0
Binder1: Binder2: Sand. Sand is accepted according to GOST 8736 c natural humidity 3–7%

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 of 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 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 information system common use- on the official site Federal agency on technical regulation and metrology on the Internet (www.gost.ru)

1 area of ​​use

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

The standard does not apply to special solutions(heat-resistant, chemical-resistant, fire-resistant, heat- and waterproofing, plugging, decorative, stress-resistant, 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 the binders used, solutions are 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 Mortar properties 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 when minimum temperature outside air, °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.

For the design age of the solution, unless otherwise specified in project documentation, should be taken for 28 days for solutions based on 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 As binding materials should be used:

- 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 added to ready-to-use mortar mixtures in the form aqueous solutions or aqueous suspensions, 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 bags made of polyethylene film according to GOST 10354 weighing up to 8 kg or paper bags according to 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 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 at his request the results control tests no later than 3 days after their completion, and if the normalized indicator is not confirmed, inform 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 Mortar mixtures delivered to the construction site, ready for use, must be reloaded into mixer loaders 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 from hollow brick or ceramic stones
For masonry from solid brick; ceramic stones; concrete stones or light rocks
For filling voids in masonry and feeding with a mortar pump
For making a bed when installing walls made of large concrete blocks and panels; jointing of 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 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

Mortars made from a mixture of sand, lime and cement are used for niches on wooden, concrete and stone surfaces. For plastering works ready-made finishing heavy lime mortar is used in accordance with GOST 28013-98.

Characteristics

The main parameters that determine the properties of the prepared solution are:

1. ability to retain water;
2. mobility;
3. degree of delamination;
4. average density;
5. temperature conditions of use.

Freshly prepared mixtures are tested for water retention ability by factory laboratories. These figures should not be less than 95% in winter and less than 90% in summer.

Important. As a result of transportation to construction sites, the water-holding capacity of the finished solution may decrease, but should not become less than 75% of the value that was established by the laboratory. It is strictly forbidden to add water to already set solutions.

Low degree of delamination ready-made compositions is very important, as it reduces the possibility of separating it into liquid and solid fractions during transportation and pumping through hoses.

The main properties of the composition in hardened form are:

1. frost resistance;
2. its compressive strength;
3. density.

All these properties must be acquired by the hardened composition at the design age, which is determined at 28 days. The only exceptions are mixtures with gypsum binders.

Ready-made lime finishing heavy mortar according to GOST 28013-98 must have an average density of at least 1500 kg/m3.

Strength for finishing ready-made mixtures much lower than that of concrete or masonry mixtures. The fact is that plaster compositions carry virtually no load.

Preparation

There are a few possible options preparation of lime mortar mixtures for production finishing works. Required mixtures can be ordered from mortar factories or special mortar units. They can also be produced directly on construction site ().

In factory conditions

The process of factory preparation of solutions consists of precise dosing of the initial components, loading them into the container of the mortar mixer and high-quality mixing there. The purpose of mixing is to obtain a homogeneous mass in the drum.

Structurally, mortar mixers differ in whether they have a vertical or horizontal blade shaft. They come in various volumes from 30 to 900 liters.

Important. In order for the prepared solution to have the desired properties, it is necessary to achieve homogeneity of the composition by stirring. For this purpose, the minimum kneading time is limited. For heavy lime mortars, the mixing time cannot be less than 3 minutes.

Ready-made solutions are delivered from factories to construction sites by dump trucks or vehicles that are specially equipped for this purpose. During transportation, it is necessary to exclude the possibility of loss of material, its moistening by precipitation, and sudden changes in temperature.

To protect the composition from hypothermia in winter, car bodies must be insulated or heated. At construction sites, the finished finishing mortar is supplied to the place of application through pipes or unloaded into special buckets, which are lifted to the floors by a crane.

Under construction conditions

The finishing solution required for plastering work can be prepared directly at the construction site.

This is beneficial when:

1. the concrete mortar plant is located at a very considerable distance from the construction site, the price of one cube of mortar, including delivery, is too high;
2. The volume of plastering work is small, so buying a whole machine of mortar is not profitable.

In this case, you can prepare the lime mortar with your own hands, following the necessary technology.

Step-by-step instructions for preparing heavy cement-lime mortar:

1. first of all, the day before cooking, you need to slak the lime, quicklime put it in a metal bucket, fill it with water and close the lid, pressing the lid with a weight;
2. after the end of the chemical reaction in the bucket, filter the resulting composition through gauze;
3. sift the sand through a metal mesh with 3x3 mm cells;
4. prepare a box or trough, the depth of which will be approximately 20 cm;
5. pour sand in a heap in the center of the trough, taking into account that 1 part of cement will be 3 parts of sand and 1 part of lime milk;
6. pour cement on top of the sand and mix;
7. add 1 part lime milk and mix until smooth.

You can use your own prepared solution only on the day of production. It is clear that when dosing components you can make a mistake and not get the material of the desired quality.

Optimal results can be obtained by using ready-made, factory-made building mixtures. All the components have already been selected and mixed, all that remains is to add water.

The use of dry plaster mixtures for the production of finishing solutions increases labor productivity and improves the quality of the work performed. Kneading can be done in small portions, using a drill with a special attachment - a mixer - to better mix the composition.

Summary

Lime-cement mortars are obtained by mixing a cement-sand mixture with lime milk and are used for plastering work inside and outside buildings (). In the video presented in this article you will find additional information on this topic.

M4 lime mortar is often used for facade and interior finishing work, and is also successfully used for laying bricks. Mixtures based on slaked lime, which have proven themselves well for a long time, are distinguished by their plasticity, good heat-saving properties, and relatively low cost; and also because they harden rather slowly (this provides advantages during transportation). True, these compositions are inferior to their cement counterparts in strength.

Lime mortar components: water, lime (as a binder), filler (sand, gypsum or cement) and modifiers that help improve the properties of the mixture. Moreover, the binder component is used in the form:

• fluff (slaked lime or dry calcium hydroxide);
• lime paste, which is obtained by reacting quicklime with water (2 kg of lime is poured into 1 liter of water);
• lime milk (for 2 kg of lime there are 2 liters of water).

Classification of solutions

Lime mortars are classified according to the type of filler, the amount of lime content, density and physical and mechanical properties.

Based on the type of filling component, lime mortars are divided into simple and complex. If a simple mixture contains only lime, then a complex mixture also contains sand, gypsum, cement or clay.

According to the amount of lime content, solutions are thin, normal and fatty. Lean mixtures contain the least amount of lime and the most amount of sand, gypsum or cement (the ratio of the binder component to the filler is 1:5). In fatty compositions, the proportion of lime is 50% or more relative to the filling material. The main advantage of fatty lime mixtures is their plasticity.

Attention! Applying too thick a layer of grease will cause significant shrinkage and cracking.

The most dense are lime-cement mortars, which cannot be said about lime mixtures with gypsum: they are less dense.

There are two indicators that characterize the durability of the mixture - strength and frost resistance. In terms of compressive strength, M4 lime mortars are the least durable compared to other brands (for example, M25, M50, M75), and in terms of frost resistance, these compositions are not controlled at all.

Preparing lime mortar for plastering

Since it is quite easy to make lime mortar for plaster, it is often used for finishing walls and ceilings. Technological process The installation of plaster includes three stages: spraying, primer and covering (total layer thickness - no more than 25 mm).

To prepare a plaster solution for spraying, mix fluff and sifted sand in a ratio of 1:3 or 1:4; for priming - in a ratio of 1:2; and for “covering” – 1:1.5. Then pour water and mix (be sure to remove quicklime pieces from the mixture).

Advice! For more convenient stirring of the mixture, we recommend initially mixing only 1/3 of the required volume of sand and water with fluff, then adding the remaining water and sand and mixing everything thoroughly again. Moreover, we pour water from a watering can, and do not pour it in a direct stream.

We get the fluff as follows:

• We place the lump lime in a metal (without signs of corrosion) or wooden container (not plastic).

Important! We choose the container volume taking into account the fact that during the extinguishing process the fluff will increase by 3÷4 times.

• Fill the lime with cold water (1 liter of water per 2 kg of fluff) and cover with a lid. The boiling process begins.

Important! When extinguishing occurs chemical reaction(rather stormy), which is accompanied by large heat release. Therefore, the use of goggles, protective clothing, rubber gloves and boots is mandatory.

• After boiling, mix the mixture thoroughly and let the solution brew for 2 weeks.
• Before direct use, sift dry calcium hydroxide through a construction sieve (to prevent poorly quenched particles from getting into the mixture).

Compositions based on fluff have a number of advantages:

• plasticity;
• antibacterial (especially important when finishing wooden surfaces);
• relatively low cost;
• sufficient drying period.

Disadvantages of such mixtures:

• Lime hardens slowly: therefore, such a composition begins to “float” after a day.

Advice! When plastering walls, apply the second layer of the mixture only after the first has completely dried.

• Lime absorbs moisture well: therefore, it is not recommended to finish rooms with high humidity mixtures based on it.

Lime-cement mortars

Cement-lime mortars are successfully used for facade finishing buildings and for plastering the walls of premises with high humidity(over 65%). Cement, which is part of the lime mortar, increases water resistance, frost resistance and strength, and lime gives the mixture good plasticity. The disadvantage of lime-cement mortar for plaster is its relatively high cost (due to the high cost of cement).

For spraying, mix sand, cement and lime in a ratio of 2:1:5; then pour in enough water so that the mixture has the consistency of liquid sour cream. Apply a thin layer of this solution onto the wall using a trowel. There is no need to level it.

Algorithm for preparing the composition that we use as the main layer of plaster (thickness should not exceed 50 mm):

• mix the dry components of the mixture: cement (grade M400) and sand in a ratio of 1:2, 1:3, 1:4 or 1:5 (depending on how heavy the finished finishing mortar should be);
• in a separate container, dilute the lime dough to the consistency of a suspension: to do this, mix the dough and water in a 1:1 ratio;
• pour this suspension into cement-sand mixture and mix (moreover, the mass of the suspension is equal to the mass of cement);
• Continuing to stir, add water until the required thickness is obtained.

Apply the main layer of plaster to the wall; remove the excess using the following rules; check the level vertically and horizontally.

Then we apply a thin finishing layer (the composition is the same as for the spray) and level it.

On a note! In order to obtain a plastic plaster mortar, for 25 kg of cement you will need: 14 kg or 37 liters of lime, 235 kg of sand and 60 liters of water. And to get a durable composition: 25 kg of cement, 7.5 kg or 18 liters of lime, 175 kg of sand and 50 liters of water.

Lime-gypsum mortars

If there is a need to obtain a composition that sets quickly, then prepare lime mixture with plaster (hardening time - about 10 minutes):

• prepare the usual composition based on fluff and divide it into two parts;
• combine the first part with gypsum in a ratio of 2:1 and mix;
• add the second part of the composition based on fluff to this composition with gypsum and mix again;
• use the resulting mixture for 5-8 minutes (while continuing to constantly stir the mixture).

Such compositions are characterized by: fine grain size and lack of shrinkage. Disadvantages: the need to use them in as soon as possible and impossibility of use in wet areas. Most often, such mixtures are used for internal plastering premises (they are rarely used outside).

Lime mixture for bricklaying

The scope of application of lime mortars for bricklaying is quite limited: they are mainly used for the construction one-story buildings(lightly loaded walls and interior partitions). The main advantages of this masonry mortar are its plasticity, low thermal conductivity and good adhesion. The disadvantages include low compressive strength (0.4 MPa) and fragility. Prepare lime mortar for bricklaying:

• Mix dry calcium hydroxide and sand in a ratio of 1:3, 1:4 or 1:5 (it all depends on the fat content of the binder).

Advice! To avoid the presence of lumps in the solution, sift the dry components of the mixture through a fine sieve.

• Stirring constantly, add water in small portions and bring the mixture to a consistency reminiscent of thick sour cream.

Lime mortar for masonry must meet the following requirements:

• be quite plastic in order to completely fill all the voids in the bricks and smooth out the unevenness of the seams;
• be strong enough not to cause wall deformation;
• remain flexible for a long time until hardening.

Instead of lime, you can use a cement component in the mixture. So, for example, using M400 cement, we mix cement, lime and sand in the ratio: for the M75 mixture – 2:1:10; M50 – 1:1:8. For cement M300: composition M75 – 2:0.5:8; M25 – 1:1.7:12. For cement M200: M75 – 2:0.5:5.

In custody

When starting plastering, you can, of course, buy a ready-made building mixture, but you can also use a homemade one, since preparing a lime mortar for plastering with your own hands is not particularly difficult.