Cement-lime mortar is a mixture with high adhesion, strength and elasticity. Proven as a masonry mortar for building blocks and bricks, as well as for plastering various surfaces indoors and outdoors. The scope of application is not limited finishing works, this also includes laying pipes, processing reinforcing mesh, and pouring monolithic floors. One of the most important advantages This composition is reliable and moisture resistant.

In addition to the above properties, lime is also characterized by its bactericidal properties, which prevent the formation of fungi and molds. It is worth noting, unlike cement mortar, the material’s ability to transmit moisture, which has a positive effect on the level of humidity inside the room. Hence, it is resistant to temperature changes up to 65 °C and frost-resistant to -50 °C.

Good adhesive properties make it possible to work with any materials, even wood. The mixture is easy to apply, filling even the smallest cracks and irregularities. The increased plasticity of lime mortar allows you to extend the drying time to three hours, thereby avoiding cracking.

According to the characteristics of fat content, the following lime compositions are distinguished:

1. normal – with an optimal degree of ductility, practically no cracking or shrinkage when drying;

2. skinny – used for any facing works, as they have minimal shrinkage;

3. fatty – highly plastic material with a large amount of binders, therefore it is well used in the form of masonry mortar.

Fat content can be adjusted by adding various components. So, to reduce the value, porous sand is added, and lime increases the fat content back.

Based on density ratio, solutions are divided into:

• low density – up to 1500 kg/m3;
• medium density – from 1500 kg/m3.

The ratio of the components of the solution determines the scope of its application. The most popular brands are M75 and M50. For example, the M75 mixture has proven itself best as a reliable masonry mortar for bricks. Whereas for a wider area of ​​use, as well as for carrying out plastering works let's digest M50.

Applied to plaster mixtures they are conventionally divided into:

1. basic – for rough leveling the surfaces of walls and ceilings;

2. decorative – having decorative elements in the structure or due to prolonged drying, they are easily subjected to texture processing followed by painting;

3. special – are of a technical nature to improve moisture-proof properties, sound insulation and insulation.

Manufacturers and prices

Another advantage is the affordable cost of the material compared to cement-sand mortar. Its low consumption (1 m2 layer of 1 mm - 1.5 kg of mixture) causes economic benefits. Lime mortar can be purchased from manufacturers ready-made or in the form of a dry mixture packaged in bags. Construction manipulations inside the premises are allowed powder formulations, whereas for outdoor work, especially if high humidity, it is recommended to entrust the preparation to professionals.

The cost depends on the quality of the raw materials used and the ratio of ingredients. Exemplary price range listed in the table below.

The range of manufacturers of ready-made dry mixes is quite extensive. All of them have their own characteristics, features in composition and scope of application. Below are the most accessible and common ones.

Product name	Volume, kg	Price, rubles
KNAUF Sevener plaster and adhesive mixture	30	430
Found PC21 STARTWELL cement-lime plaster	25	208
Cement-lime plaster m-100 BESTO	50	170
Cement-lime plaster – Moment Henkel	50	184
Lime-Cement Plaster GP-31 Hercules	25	247
Cement-lime masonry RUNIT	25	234

Making your own solution

In addition to ready-made production options, it is possible to make lime mortar yourself. Buy all the necessary high-quality elements and carefully observe the proportions to achieve a high-quality result while saving money. The main ingredients used are cement, sand, lime and water.

The ratio of ingredients determines the brand and specifications.

Brand of cement for preparation	Brand of lime composition
	M200	M150	M100	M75	M50	M25	M10
	Proportion of components – cement-lime-sand
M500	1:0,2:3	1:0,3:4	1:0,5:5,5	1:0,8:7	—	—	—
M400	1:0,1:2,5	1:0,2:3	1:0,4:4,5	1:0,5:5,5	1:0,9:8	1:1,9:12,5	—
M300	—	1:0,1:2,5	1:0,2:3,5	1:0,3:4	1:0,4:5	1:1,3:10	—
M200	—	—	—	—	1:0,2:3,5	1:0,7:6,5	1:2:16
M150	—	—	—	—	—	1:0,3:4,5	1:1,5:10,5
M100	—	—	—	—	—	1:0,1:3	1:0,8:7

Water consumption during preparation is usually 0.8 parts per 1 hour of cement. In practice, the amount of liquid is determined visually by the consistency of the solution - normally the mixture should resemble thick sour cream.

Lime, as a building material, is used only in quenched form, otherwise the result will be chemical reaction the finished material may swell or rupture altogether. For preparation you will need a separate container. The process varies depending on the rate of extinction.

1. Quick-quenching lime is poured into a barrel of water until completely immersed. After steam appears, add more water and mix. Extinguishing takes an average of 8 minutes.

2. Medium-slaking lime is poured into a container and filled with water in double volume. When steaming, water is also added and mixed. The process lasts approximately 25 minutes.

3. Slow slaking lime is only moistened with water. The reaction is accompanied by a threefold increase in volume and an increase in temperature. Takes more than 25 minutes.

The prepared material is diluted with water in a 1:1 ratio to the state of lime milk. Often, to carry out the final extinguishing, it is poured into a special pit, sprinkled with a layer of sand and earth and kept in this way for 15-20 days. The composition acquires a creamy consistency and is now called lime dough or paste.

For cement-lime plaster mortar, the following is most often used as binder cement:

• Portland cement type I with minimum quantity additives and high setting speed;
• Portland cement type II grades M500-400 with additive content up to 35%.

As practice shows, on construction sites Three-layer plastering is most often used. The proportions of the solution (water-sand-lime-cement) in this case will depend on the layer of plaster.

• rough layer – spray – 2.2:6.7:1.5:1;
• middle layer – soil – 2.8:9:2.2:1;
• finishing layer – covering – 4:13.5:3:1.

To prepare masonry cement mortar, it is more advisable to use a concrete mixer, since in practice more of it is required than plaster. The latter, in turn, is prepared in improvised containers using a construction mixer.

Part of the water is poured into the concrete mixer, then cement, lime and sand are added alternately required proportion. After thorough mixing, the mixture is mixed with the remaining water.

In the case of manual cooking, there are two types of procedures:

1. Lime dough is passed through a sieve with a cell diameter of no more than 3 mm. Then sand and cement are added to it in portions, everything is thoroughly mixed until the required fat content of the solution is obtained.

2. A dry mixture of sand and cement is prepared in the required ratio. Lime milk is gradually poured into it, if necessary, diluted with water to achieve the required consistency.

To increase the stability of the solution to environmental factors and slow down the hardening process, the following is added to the finished mixture:

• plasticizers;
• frost-resistant additives;
• retarders and others.

The Portland cement used in the composition also brings a number of positive characteristics material:

1. in combination with the action of hydraulic additives, it provides resistance to leaching, and therefore to long-term exposure to ground and sea waters;

2. attaches cement high level anti-corrosion protection;

3. lime mixtures with Portland cement are not prone to destruction even with seasonal changes in freezing and thawing regimes.

GOST 28013-98

INTERSTATE STANDARD

BUILDING SOLUTIONS

General technical conditions

INTERSTATE SCIENTIFIC AND TECHNICAL COMMISSION
ON STANDARDIZATION, TECHNICAL REGULATION
AND CERTIFICATION IN CONSTRUCTION (MNTKS)

Moscow

Preface

1 DEVELOPED by the State Central Research and Design Institute complex problems building structures and buildings 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 "Rosconitstroy" of the 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.

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 state standard Russian Federation by Decree of the State Construction Committee of Russia dated December 29, 1998 No. 30

INTERSTATE STANDARD

BUILDING SOLUTIONS

General technical conditions

MORTARS

General specifications

Date of introduction 1999-07-01

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, plugging, decorative, stress-resistant, etc.).

The requirements set out in , , , and this standard are mandatory.

2 Normative references

Used in this standard regulations shown in .

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.

An example of a symbol for a heavy mortar, ready-to-use, masonry, on lime-gypsum binder, strength grade M100, mobility - P to 2:

Masonry mortar, lime-gypsum, M100, P k 2, GOST 28013-98.

For dry mortar mixture, light, plaster, on a cement binder, grade M50 in strength and mobility - P to 3, medium density D 900:

Dry mortar plaster mixture, cement, M50, P k 3, 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;

Medium density;

Humidity (for dry mortar mixtures).

4.2.2 Basic properties of the hardened solution:

Compressive strength;

Frost resistance;

Medium density.

If necessary, additional ones can be installed

Norm of mobility for cone immersion, cm

From 1 to 4 incl.

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;

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

from 5 and above................................................... ................................... 15;

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

from 0 to 5................................................... .......................................... 15

from 5 and above................................................... ..................................... 10.

table 2

	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.

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 solutions: F 10, F 15, F 25, F 35, F 50, F 75, F 100, F 150, F 200.

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 Average density, D , hardened solutions at design age should be, kg/m 3

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 preparation 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.

Gypsum binders according to GOST 125;

Construction 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 according to GOST 25328;

Ash and slag sand according to GOST 25592;

Sand from thermal power plant slag 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) .................................................... ........................... 2.5

Rubble masonry................................................... ........................................................ ....... 5.00

Plaster (except for the covering layer)................................................. ................. 2.5

Plaster covering layer.................................................... ........................ 1.25

Facing........................................................ ........................................................ ...... 1.25

(Changed edition, Amendment No. 1)

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

Cement binder................................................... ........................................ 60

Cement-lime, cement-clay and clay binders........ 40

Lime, clay-lime, gypsum and lime-gypsum

binder…………………………………………………………………………………... 20.

4.14.10 The content of harmful impurities in aggregates should not exceed the requirements of GOST 26633 for fine aggregates.

4.14.11 Specific effective activity of natural radionuclides A eff of materials used for the preparation of mortar mixtures should not exceed the limit values ​​depending on the area of ​​application of 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 for binding materials, water and additives ±1%, fillers ±2%.

For mortar mixing plants with a capacity of up to 5 m 3 /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 sold in vehicle, - a quality document that must contain the following data:

Name or trademark and address of the manufacturer;

Symbol for mortar;

Class of materials used to prepare the mixture, according to the specific effective activity of natural radionuclides and the digital value A eff;

Compressive strength grade;

Mark for mobility (P k);

The 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;

Amount of mixture (for ready-to-use mortar mixtures), m 3

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 official manufacturer 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.

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 A eff 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 non-compliance with at least one of the technical requirements of the standard is revealed, this batch of mortar is rejected.

5.9 The consumer has the right to exercise control check 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, and.

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 Specific effective activity of natural radionuclides A eff 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.

(Changed edition, Amendment No. 1)

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 specifically 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 prevent loss of binder dough entering the mixture atmospheric precipitation and foreign impurities.

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

(informative)

List of regulatory documents

B.2.2 Content of sulfates and sulfides in terms of SO 3 determined according to GOST 3594.4.

B.2.3 Sulfide sulfur content in terms of SO 3 determined according to GOST 3594.4. SNiP II-3-79 *

Minimum consumption of cement in masonry mortar per 1 m 3 of dry sand, kg

Under dry and normal room conditions

In humid conditions

In wet room conditions

Key words: mortars, mineral binders, masonry, installation of building structures; masonry, facing, plastering mortars

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 lime mortar, its composition and how to prepare it yourself.

Slaked lime

Binding fillers

Before you make a solution, you need to know not only its technical characteristics, but also the proportions with which you mix it yourself. 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 produce a large amount of material, since it must be used very quickly. The average hardening speed 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 high levels of 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 the solution contains part river sand, it should be washed before use. In this case, the quarry sand 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 fatty, then gradually add required amount sand. 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 in different directions. 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, since 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 popular 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. First, they are laid thin layers(1...2 cm), without using a mechanical seal. 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

The compositions of mortar mixtures are selected 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 determining the activity (grade) and average bulk density cement, grain composition and sand fineness modulus, 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. According to their 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.

To prepare cement mortars with inorganic plasticizers, lime (clay) milk of such a consistency is poured into the mortar mixer 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 mix with water, mix and use 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 in normal conditions. Therefore, for masonry located below the level groundwater, such solutions should not be used. 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 humidity indoor air.

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 air humidity 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 that are not subject to systematic moisture, and internal plaster in rooms with relative air 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 with natural humidity 3–7%

In this article we will look at what types of mortars there are for brick and stone masonry, plaster, as well as for decorative and terrazite finishing layers. As well as methods for preparing them.

Compositions of solutions

For brick and stone masonry

The following types of mortars are known:

• by appointment - masonry mortars, plastering and special
• by type of binding materials - cement mortars, lime, gypsum and mixed (cement-lime, cement-gypsum, etc.)
• by volumetric mass - ordinary (heavy) with a volumetric mass of 1500 kg/m3 or more (on dense aggregates), light with a volumetric mass of less than 1500 kg/m3, on light aggregates
• in terms of compressive strength - grade M-4; M-10; M-25; M-75; M-100; M-150; M-200

Solutions of grades M-4 and M-10 are made primarily with lime. The strength of the solution depends on the hardening temperature. At a hardening temperature different from 18-22°C, the strength of the solution is taken according to Table 1 or determined by laboratory tests.

Table 1. Strength of the solution, % strength at the age of 28 days

Age of the solution days	Hardening temperature, o C
	0	5	10	15	20	25	30	35	40	45	50
1	1	4	6	10	13	18	23	27	32	38	43
2	3	8	12	18	23	30	38	45	54	63	76
3	5	11	18	24	33	47	49	58	66	75	85
5	10	19	28	37	45	54	61	70	78	85	95
7	15	25	37	47	55	64	72	79	87	94	99
10	23	35	48	58	68	75	82	89	95	100	—
14	31	45	60	71	80	85	92	96	100	—	—
21	42	58	74	85	92	96	100	103	—	—	—
28	52	68	83	96	100	104	—	—	—	—	—

Notes:

1. This table applies to solutions that harden at a relative air humidity of 50-60%.
2. When using solutions based on slag Portland cement and pozzolanic Portland cement, one should take into account the slowdown in the increase in their strength at a hardening temperature below 15°C. The strength of these solutions is determined by multiplying the values ​​given in Table 1 by the coefficients:
   0.3 - at hardening temperature T=0oC; 0.7 - at hardening temperature T=5oC; 0.9 - at hardening temperature T=9oC; 1.0 - at hardening temperature T=15oC and above.
3. For intermediate values ​​of the hardening temperature and age of the solution, its strength is determined by interpolation.

Compositions of solutions

Determination of the composition of the mortar is carried out in accordance with SN 290-(..), guided by the house construction project and depending on local construction conditions and the area of ​​application of the mortars.

Table 2. Compositions of mortars (by volume) for brick (stone) masonry

Type of solution	Cement brand	Brand of solutions
		100	75	50	25
Cement-lime mortar	400	1:0,3:4	1:0,5:5	1:1:8	—
	300	1:0,2:3	1:0,3:4	1:0,7:6	1:1,7:12
	200	—	1:0,2:3	1:0,4:4,5	1:1,2:9
Cement mortar	400	1:4	1:5	—	—
	300	1:3	1:4	1:6	—
	200	—	1:3	1:4,5	—

Table 3. Approximate consumption of cement grade M-300 in plaster mortars

Type of solution	Composition of solution by volume	Cement consumption per 1 m3 of solution, kg
Finishing - heavy:
cement	1:4	300
cement	1:3	400
cement-lime	1:2,5	450
cement-lime	1:2,9	135
Decorative - with stone chips:
cement	—	450
cement-lime	—	200
light cement-lime	—	250

Table 4. Solutions for stone-like (decorative) plasters

Components	Number of components, in parts by volume, when simulating under:
	white marble	yellow marble	red granite	gray granite
Portland cement:
white	1	1	—	—
grey	—	—	1	1
Lime dough	0,5	0,25	0,1	0,1
Marble flour	0,5	0,25	—	—
Marble chips	3	3	3	3
Mica (depending on the volume of cement)	0,5	0,5	0,5	0,5
Pigment (% by weight of cement)	—	Ocher 3-5%	Iron minium 5-10%	Manganese peroxide 1-5%

Table 5. Solutions for terrazite finishing layers and plasters (in parts by volume)

Materials	Plaster color
	white	yellow	brown	light gray
Portland cement:	1	1,5	1,5	1
Fluffy lime	3	4	3	2,5
Quartz sand	—	9	11	—
Marble chips	6	4	—	9
Marble powder	1,5	1	—	3
Mica (depending on the volume of cement)	0,5	0,5	0,5	—
Pigment (mass fraction of the total dry mixture), %	—	Ocher 2%	Umber 0.5%	—

Methods for preparing solutions

Solutions are prepared using mechanized on-site installations (concrete mixers or mortar mixers). In order to prepare mixed mortars with inorganic plasticizers (lime, clay, etc.), as well as cement, lime and clay mortars, in a mortar mixer:

• serve water
• then filler is loaded (natural and artificial sand)
• binders (lime, clay, gypsum, cement)
• plasticizer

The duration of mixing all components is at least 1 minute for heavy solutions and 2 minutes for light solutions. To prepare solutions with organic plasticizers, add water and a plasticizer to the mortar mixer and mix them for 30-45 seconds.

Then load the remaining materials and mix them until a homogeneous mixture is obtained, but not less than 1 minute. Decorative mortars are produced by mixing colored cements with dry filler in a mortar mixer.

Then the mixture is mixed with water and further stirred. To obtain solutions for stone-like decorative finishing layers and plasters, lime paste is loaded into the mortar mixer, colored cement or Portland cement, previously thoroughly dry mixed with dye powder, is added, and this mixture is mixed for 2-3 minutes.

Then add filler and mix until a homogeneous mixture is obtained.