Cement is a binding powder that is used for the production of masonry and plaster mortars, as well as the creation of concrete structures (foundations, screeds). To properly mix the composition with sand and water, you need to accurately calculate their proportions. If you violate the cooking technology, it will turn out too skinny or greasy, it will crack or crumble.
Depends on the destination. For bricklaying and plaster, compositions with different ratios of sand and cement are required. Only clean water is used - drinking water, rain water, but in no case lake or sea water. If it is clogged, mold will appear on the masonry or plaster over time. Crushed stone, sawdust or slag can also be used as a filler.
To increase plasticity, special plasticizers or liquid soap are added. Their quantity should not exceed 5% -10% of the volume of cement. If it is more, the adhesive characteristics of the composition will decrease. To increase resistance to low temperatures or moisture, special additives are also introduced (according to the instructions specified by their manufacturer).
It is necessary to prepare all tools and components, since the mixtures begin to set after 45 minutes if additives or fast-hardening Portland cement were not used. If you pour water into the solution after it has hardened, all of it specifications will get much worse.
Cement powder and sand are sifted through a sieve to remove debris and lumps. If the sand is damp, it is better to dry it in advance. If dirty, rinse and leave until completely dry. Otherwise, due to excess moisture, it will disrupt the water-cement ratio, and the composition will turn out liquid.
The main rule that must always be observed when kneading is homogeneity. All components must be thoroughly mixed. The presence of lumps will reduce the characteristics, including strength.
The solution can be diluted in any container. The main thing is that there is more than the amount of mixture being prepared, then during mixing it will not splash out. For this purpose, you can use a bathtub, basin or bucket. For mixing, use a shovel, trowel, drill with a special mixer attachment or concrete mixer.
The mixing sequence depends on the preparation method - manually or using a concrete mixer. If they dilute using the first method, then the measured proportions of the components are poured one at a time, first sand, then cement and water. If a concrete mixer is used, then water is poured in, and then the remaining elements are added.
Mixing time is 5 minutes. It is necessary to ensure that the mixture is homogeneous, without lumps. Density depends on the purpose of use. If you plan to use additives, then they are diluted in advance (if allowed by their manufacturer).
The ratio of sand, cement and water depends on the purpose of use. The following species may be involved:
1. For plaster. The preparation proportion is as follows: 1 part cement, 3 parts sand. The same amount of water is added as powder. If the solution will be used indoors, then the minimum grade of binder is M150-M200. For facade works M300 is used. To make the mixture more plastic and to be able to apply it in a thin layer, add lime, but not more than half the volume of sand.
2. For laying bricks. Proportion of components: 1 part powder, 4 parts sand. Water is taken half of the volume of binder, grade - M300-M400. Additionally, you can add lime (slaked) - 30% of the amount of powder, as well as 50 g of liquid soap to make the composition more plastic. The sequence of preparation is to pour in water, then cement without mixing with sand, then the rest of the fillers. The mixture is considered correctly mixed if it does not flow off a plane inclined at an angle of 40°.
3. For foundations. The components must be diluted in the following ratio: 1 part cement, 2 hours sand and 4 hours crushed stone or other coarse filler. Take half of the water from the binder M500, the minimum grade is M400. It is best to dilute such a composition in a concrete mixer, since it will be difficult to manually achieve a homogeneous and uniform consistency, especially if the volumes are large.
4. Concrete screed. In this case, only high grades are used - from M400, the proportion is 1 to 3. Half of the volume of binder is taken of water.
5. Ironing. The ratio of sand and cement is the same. Lime is added in a volume of 10% of the amount of binder.
The grade of cement should be 2 or 3 times greater than the grade of mortar. If it is necessary to mix the M300 composition, then M150-M200 powder is used, but no less. For bricklaying you will need M50-M100, plaster - M50-M100, concrete screed– M100-M200, foundation – M200-M300.
You should not take cement that has been stored for a long time in open form. Even packaged powder loses some of its strength after 2 months from the date of manufacture. Old cement can be used only for those jobs where it will not be subjected to stress or be exposed to aggressive conditions. In order to increase the grade of the solution in this case, it is necessary to increase the proportion of the powder.
When mixing the mixture, it is not recommended to pour in the entire volume of water at once, but only a large part of it, approximately 85%, then add the rest. To properly pour in liquid soap without forming foam, dilute it in advance and let it sit for several minutes, during which time the foam will disappear. Afterwards it is slowly poured in and stirred for another 5 minutes.
Cement-sand mortar should be diluted at a temperature not lower than +5°C. When mixed in a concrete mixer, it will turn out much better than when mixed manual way. The finished composition must be used immediately after production. For increase thermal insulation characteristics Some sand can be replaced with perlite. If you need to mix a large volume, then it is better to first make a test batch and make sure that the ratio of components is correctly selected. To avoid mistakes in proportions, it is recommended to purchase a special dispenser.
The most common material, without which almost no construction work can be done, is one of the varieties cement mixture- this is concrete. An irreplaceable component of concrete is cement.
It is on whether the cement mass was mixed correctly that the future strength of the foundation, the reliability of road surfaces, and the quality of brickwork and plastering.
Surely, each of us at least once in our lives has encountered concrete works. Not everyone can cook concrete mortar I succeeded the first time, so you can often come across the following questions: “How to dilute cement without sand? What proportions of sand and cement should be observed? What is the solution consumption per 1 m 2? etc.
So let's look at these nuances together.
I would like to immediately note that cement, as a means of bonding, is used exclusively as solutions and mixtures that determine the following nuances:
You can dilute cement and combine the necessary ingredients as in plastic container, and in metal dishes. For these purposes you can use:
The cement-sand mixture is prepared as follows:
To understand that the mixture is mixed according to all the rules and its consistency has the necessary viscosity, you need to do some manipulations. To do this, the mass is applied to the surface of a trowel or spatula and turned over with the solution facing down. If the substance does not flow down, but remains on the surface of the instrument, the solution is prepared correctly.
Pay attention to how long it takes for the cement to dry. The finished solution must be used within a maximum of 90 minutes.
Sand and cement
So, let's look at how to prepare a mixture for the most popular jobs.
For plastering, it is best to use a proportion of 1:3 (where 1 is the amount of cement, and 3 is the amount of sand). Basically, water is used in the same quantity as cement, but it must be poured in small portions so that the density can be controlled. To prepare such a solution, you need cement powder of the following brands: M-150, M-200 (with internal works) and M-300 (for facade finishing). If you want to make the mass more flexible so that it lies evenly and smoothly on the surface, add lime to it. Its amount should be ½ part of sand.
For bricklaying, a ratio of 1:4 is used, and cement powder is required in grades such as M-300 and M-400. For viscosity, you can also add 0.2 or 0.3 parts of lime. Water also flows into dry matter until the required mass structure is formed. To ensure that the prepared solution is correct, throw it onto the surface at an angle of 40 degrees. If it doesn’t drain, you did everything right.
For these purposes, the equation 1:3 is followed, and cement is selected at number 400. For mixing, you will need ½ part of the water from the amount of cement used. Try to control the consistency of the solution all the time, because the mass should stretch easily to fill all the gaps and cracks. As a result, you will get a solution labeled 150.
To prepare such a polymer-cement composition, you will need more ingredients: cement powder, sand, gravel or crushed stone. Their proportional ratio is 1:2:4. If you are preparing a solution for pouring the foundation of a house, select cement number M-500. You will need half as much water as cement. Thus, you will get concrete of class M-350. This prepared mass must be consumed before 60 minutes have elapsed.
We make cement with our own hands
Please note that the cement-sand mass must have a grade higher than the grade of cement by 2.5-3 times.
What the approximate consumption of materials for plastering m2 of surface looks like can be seen in the table below.
We dilute cement ourselves
Cement floors or walls are not a very attractive sight. But even such an unsightly mass can be easily transformed with the help of special means.
To add color to the gray mass, you can use:
How to dilute such funds? In order for the cement dye to fulfill its “mission”, it will be enough to mix it into the finished solution, after which the result is a substance with the most durable color, which does not lose its brightness for many years.
This cement paint is widely used in the production of paving slabs, natural tiles or paving stones.
The pigment for cement must meet the following requirements:
As you can see, there is nothing complicated in coloring and mixing cement, but you can get the desired shade: from the usual gray to pink, blue, yellow or green.
Construction and repairs always require cement, which must be mixed with sand in certain proportions. The resulting mixture has a strong viscous consistency, capable of bonding natural stone, bricks and even concrete blocks. Due to the fact that water is added to the solution, when dry, all building materials are firmly bonded to each other and form a single monolith.
Cement-sand mortar is used for laying bricks and ceramic tiles, pouring the foundation, paths and plastering walls.
Before you begin the process of mixing all the components in the required proportions, you should know for what purposes it will be intended and what tools are needed for this work.
The most common binding material is cement.
To mix the mixture by hand, you will need a metal container and a shovel or garden hoe.
Today this is the main component for any mortars and various concrete mixtures. Positive qualities of this material are the speed of drying and strength. Visually you can also determine the strength of cement: the darker its color, the stronger it is.
Aluminous cement is characterized by heat resistance, high water resistance and quick drying. Most often it is used in industrial construction. Portland cement is mainly used in the construction of private houses, renovations and other small needs. Its classification directly depends on the strength and speed of hardening.
To obtain a homogeneous mixture, the sand must be sifted.
Please note that it is recommended to use clean river sand for mixing. It is in its composition that there is no clay, which has the ability to be washed out of the finished material in the rain. But clay admixtures in great content observed in sand taken from a quarry. If it is not possible to use river sand, then you can take a quarry one, but only an alluvial one. Before you start mixing, the sand should be sifted to remove all excess impurities and stones. Otherwise, the finished construction product will have a non-uniform consistency, which means it will be of poor quality.
First you need to mix the dry ingredients - cement and sand in a concrete mixer in a ratio of 1:3.
In order to do this, you need to adhere to the appropriate proportion of all components when mixing. It is equally important to ensure that the dry mixture is homogeneous. All this is required so that after the mass hardens, cracks and voids do not appear, and the tiles and bricks are well grasped by the mortar.
Water is gradually added to the dry mixture until it reaches the consistency of thick sour cream.
For this work, the following proportions are used: 1:2 or 1:3, that is, 1 part cement and 2 or 3 parts river sand.
Those who have dealt with construction and repair work have at least once had the question of how to properly prepare cement, since it is one of the most common bases used in construction and repair work. Often, when mixing the mortar, builders do not comply with the mixture preparation proportions required by the standards, which affects the final result: the structure made in this way becomes unusable over time. In this regard, the correct technique for diluting cement is discussed below, by doing which you can get quality solution for future construction.
Cement has long acquired the status of the most popular material used for construction. With its help, concrete is produced, which is used for the foundations of future structures. The cement composition is the main binder for obtaining a concrete mixture.
Cement itself is a binding mineral powder, which, when combined with water, becomes a viscous grayish mass and after some time hardens in the open air.
The powder is made by grinding clinker and then adding minerals and gypsum. Thickened cement can be adversely affected by aggressive environments and plain water. To improve performance, a hydroactive material is added to the cement composition to prevent the penetration of salts. Corrosion resistance increases when raw materials are added to the initial composition - special polymer additive, which significantly reduces porosity and prevents adverse physical and chemical effects on the environment.
All kinds of cement compositions absorb different amounts of water. The grain size of the material has a fairly high density, three times the density of water. As a result, when adding large quantity With water, part of the cement will not dissolve, but will appear on the surface of the prepared solution. Therefore, the material will settle, and the top of the structure from the resulting cement mortar will result in an unstable and cracking structure.
The cost of the material depends on the quality of its grinding: the finer the components of the cement, the more people will pay for it. This is directly related to the setting speed: a finely ground composition will harden much faster than coarsely ground cement.
To determine the grain composition, the material is sifted through a sieve with cells less than 80 microns. With a high-quality cement composition, most of the mixture is sifted. But we should not forget that fine grinding is of better quality, but in the future it will require more water. Therefore, it is recommended to give preference to a composition that has both small particles(up to 40 microns), and large (up to 80 microns). In this situation, the cement mixture will have all the necessary and acceptable properties.
The ability to thaw and freeze is one of the main characteristics of a cement mixture. Water located in porous areas of a cement structure expands in volume up to 8% at low temperatures. When this process is duplicated, the concrete cracks, which contributes to the destruction of the constructed structures.
In this regard, in construction work ah cement is not used in pure form. Wood pitch, sodium abietate and other mineral additives will help increase the service life and strengthen the stability of concrete.
Before making a cement base, you need to determine for what purpose it will be needed. Each mixture requires specific ratios. Below are the most common options for preparing cement mixtures.
Thanks to this component, you can obtain a plastic material that is quite comfortable and easy to use. The required volume will be determined during the addition process until a solution of the required consistency is obtained. It is recommended to obtain a mixture that will not flow off the spatula at an angle of 40 degrees.
For better screed you should not pour in the full volume of water, since it is extremely important that the mixture becomes plastic and stretches well - this will guarantee that all empty areas on the base of the screed are filled.
Mixing should be done in a concrete mixer. The resulting concrete mixture must be applied within an hour. To get more quality composition alabaster should be added.
It is recommended to mix cement at home with your own hands in a container made of metal or plastic. To do this you will need a shovel, spatulas and a drill with various attachments. For large volumes of cement preparation (from 1 to 3 cubic meters), it will be more practical to use a concrete mixer. All necessary tools, materials, as well as the place for breeding, are prepared long before the start of work.
It is worth remembering that the prepared mixture must be used immediately after receiving it, then it begins to harden and its use is impossible.
The sand must be washed and dried in advance. Wet fillers are not added under any circumstances - this will disrupt the ratio of water and cement. The conformity test is determined as follows: the grade with the resistance determined at the factory is divided by the number of parts of sand. It is preferable to mix cement using clean water(melt, rain and drinking water can also be used). In order to impart plasticity, you can introduce a soap solution, lime, a plasticizer, but do not violate the norm: more than 4% of the astringent portion of the composition.
The order in which materials are introduced into the container is determined by the mixing method. If specialized equipment is not used, then sand is sifted into the container, then cement, and then water is added. Using a concrete mixer, water is first added, then sand and cement. With any method, the cement base is diluted within 5 minutes. During this period of time, the base should become a homogeneous consistency.
A well-diluted mixture remains on the spatula and slowly drains from it, and if you turn it over, there are no lumps or poorly diluted particles in it.
Sifting sand may seem like a boring and unnecessary task. But if there is a need to get high-quality and flat surface, then you should get rid of all kinds of impurities in the sand. For sifting, you need to use a sieve or mesh with small cells.
Another budget option is to drill holes in the bottom of the bucket using a thin drill bit. For a large amount of sand you can build wooden frame, on which you need to stretch a metal mesh. After this, all that remains is to place the sand and shake the edges of the frame. The resulting material with fine grains is perfect for a cement mixture.
To obtain a homogeneous mixture, sand and cement can be mixed using a special drill attachment or spatula. If necessary, you can mix a larger volume of the mixture - in this case, use a concrete mixer or a wide bath in which all the components are mixed with a shovel. A budget option is to use a piece of old linoleum as a base for stirring the solution.
After obtaining a homogeneous solution, the required volume of water is added, which is approximately equal to the amount of cement mixture. You should stir it constantly until you get a homogeneous mass. You should not achieve an overly liquid consistency - the solution should set well enough and not run off when turning the spatula over.
When purchasing finished material, you must be sure that it was prepared immediately before being sent to the buyer. It is advisable to study all the information about the product before making a purchase to make sure what components the solution consists of, as well as how to use it.
