How to make a good cement mortar. Cement mortar. Preparing water for solution

Cement-sand mortar is the basis for both the foundation and the laying of walls. Very often, due to poor-quality mortar, a building begins to collapse within a few years due to deformations. Now we will talk about how to properly make a foundation mortar with your own hands, and also consider the requirements for the components of the mortar.

Requirements for the components of cement-sand mortar

The main components of cement-sand mortar are water, cement (binder) and sand (aggregate). Also, depending on the various conditions under which the cement-sand mortar is produced, it is recommended to add all kinds of hardeners and other auxiliary additives. In order for the solution to be durable and of high quality, the first step is to correctly select its main components.

Firstly, water. It should be clean, tap water will do. The water should be free of oil and acid impurities, construction waste and other pollutants.

As for sand, it also has special requirements. Sand should not be mixed with clay or other rocks. It is best to use river sand.

Cement must be selected based on the purpose of the solution. If in the future it will be used to fill the foundation, then it is recommended to choose cement of at least grade M300, or even M400. Cement in paper bags doesn't have a bad reputation, which is why it's recommended. A very important requirement for cement is to buy it 1-2 weeks before the start of construction, because... Over long periods of storage, it begins to harden and becomes unusable. If you nevertheless buy cement long before the start of construction, it must be carefully wrapped in plastic film to prevent the influence of moist air on the material.

If you decide to make not a cement-sand mortar, but a concrete mortar with your own hands, then you need to add another important component to it - crushed stone. The purpose of crushed stone is another mortar filler, which will not only significantly save cement consumption, but also make the mortar more durable. The following requirement is imposed on crushed stone: the particle sizes should not be too small, but not too large. The most ideal option is particles with a diameter of 2.5 - 3.5 cm.

For example, to make the solution more elastic, they add a detergent that is not very expensive.

Also, one of the popular additives in cement-sand mortar for masonry walls are dyes. Their purpose is to make the seam darker or lighter, at the request of the owner of the building. Soot is used as the simplest additive, but you need to be careful with it, because its excessive amount reduces the strength of the cement mortar.

We have provided you with the most important requirements for the components of a cement-sand mortar; now let’s move on to what proportions of a cement-sand mortar are most suitable.

The most suitable proportions of cement-sand mortar

In order for the cement-sand mortar to be durable, it is necessary to correctly select and calculate its proportions. To lay walls, it is necessary to create a grade of cement mortar M100. To do this, you can take M400 grade cement and make the proportion of cement to sand 1:4. To create other grades of mortar, we use the same method, for example, to get a cement-sand mortar of the M200 brand, mix 2 buckets of sand and 1 bucket of M400 cement.

It should be noted that creating a durable mortar (M300 - M350) is not always advisable, because this entails increased cement consumption (and therefore higher material costs), and also will not provide an order of magnitude higher strength.

We also draw your attention to the fact that the most successful proportion for summer cottage construction work is the ratio of cement and sand 1:3.

For rough masonry of walls, it is allowed to add clay to the mortar, which will add elasticity to the mortar and reduce the cost of building materials.

How to make a cement-sand mortar with your own hands?

First of all, you need to choose the option of mixing the solution - with a concrete mixer or manually, we will analyze both options.

It is clear that mixing the solution using a concrete mixer will significantly save both health and strength and, of course, construction time. The only problem is that the construction itself requires a lot of material costs and there is not always money left over to purchase an inexpensive but useful concrete mixer. In this case, we have already provided an article on how to easily and quickly make a functional .

So, let's return to the process of mixing with a concrete mixer. First of all, add water, not too much, but not too little, approximately 60-70% of the total amount of water needed.
Next, add about 100 grams of detergent to the water and wait until it is thoroughly mixed with water (about 2 minutes).

After this, add half the amount of sand and all the cement necessary for the solution. The solution must also be thoroughly mixed; if necessary, a little water is added to it.

As soon as the solution becomes homogeneous, add the remaining amount of sand to it and wait until everything is completely mixed.

You need to add so much water that the result is the consistency of liquid sour cream.

It should be noted that a solution that is too thick will be inconvenient to work with, just like a solution that is too thin. Moreover, in the latter case the solution will lose its strength properties.

Now let's move on to the option of mixing the cement-sand mortar manually. To do this, first prepare a container where we will mix (a trough will do).

Next, pour the entire dry mass (cement and sand) into the trough and mix thoroughly until it has a homogeneous consistency. After this, water is added to the mixture (little by little) and mixed until a creamy consistency is formed.

A very important point is that the cement-sand mortar sets quickly, so if you work alone, mix no more than 30 liters of mortar.

You should also pay attention to the fact that in winter the water needs to be slightly heated so that the solution does not set so quickly, otherwise the water will freeze and the strength of the foundation or masonry will noticeably decrease.

In summer, on the contrary, it is necessary to use cold water (like from a tap). If it is too hot, the poured solution must be wetted by hand several times a day, otherwise the foundation will crack.

This, in fact, is all I wanted to tell you about how to make a cement-sand mortar with your own hands. We hope that the article was useful to you, and we wish you good luck in creating summer cottages

DIY buildings!

There are a different number of options to implement preparation of solutions. Let's consider the most reliable, optimal and fastest method.

Water for preparing the solution.

If you are preparing a classic solution in a concrete mixer, then first of all you need to pour water into it. Do not trust any formulas, because it is impossible to determine in advance how much water will be needed. For example, when using wet sand, much less water will be needed. The simplest method of oriented calculation is based on the amount of cement. For example, mixing one bucket of cement will require approximately the same amount of water. To prevent the solution from turning out liquid, add a little less water than normal. Online calculation of the composition of cement mortar.

In the meantime, if there is not enough liquid, then periodically you will have to add sand or cement, or add water. This will take a lot of time solution preparation process. If you add slightly less liquid than normal, then mixing sand with cement will take place many times faster than with a thick solution. After adding the last portions of sand and cement to the concrete mixer, the necessary remaining liquid is added by eye. For faster and better mixing of cement and sand, they must be in a liquid state. At the end of the kneading, the desired thickness of the solution is adjusted. If the solution turns out to be quite liquid, don’t worry, it’s all fixable. Just add a little sand and cement of the required grade (1:4, 1:3, etc.) in the same proportions.

Detergent in the preparation of the solution.

This is a very unusual but useful supplement. With its help, the solution becomes elastic and thereby improves the quality of the resulting solution. For these purposes, it is best to use dishwashing detergent or liquid soap. The quality and brand of detergent does not matter, what is important is that it foams. If you are planning a large amount of solution, then it is much more profitable to buy detergents in five-liter plastic bottles, because it is always cheaper in bulk.

Approximately 50-100 grams of detergent are added to the concrete mixer. It is impossible to calculate its specific amount, since this is influenced by various factors. This component is added after pouring water, then they react well with each other and foam well. Three to five minutes will be enough for the dissolution and foaming process to complete in a running concrete mixer. Do not add detergent at the end of the batch, otherwise it will not affect the solution.

After the detergent has dissolved well, you need to add sand. However, all the sand is not poured in at one time; only half of the amount required for the entire batch is required. For example, for preparing a solution of grade 100 And cement grade 400, when first added, only two of the four required parts are filled in.

Cement in the preparation of mortar.

After half the sand, cement is added to the concrete mixer - in full quantity for mixing. It mixes with sand and water after a couple of minutes.

Sand in the preparation of the solution.

The rest of the sand is added when all the ingredients placed in the concrete mixer are completely mixed. If required, the missing part of the sand is added and upon completion the density of the solution is adjusted. After this, the solution is finally mixed for three to five minutes.

In the end, the solution should be not very liquid and not very thick. The consistency should be very similar to store-bought sour cream. The shape of the solution should hold very well. To make sure of this, you can try to draw or write something on the surface of the solution. The written text should not blur.

Tip: for preparing a high-quality solution double kneading(about eight buckets of sand-cement mixture) will only take fifteen minutes.

Application and production of cement mortars at subzero temperatures.

At sub-zero temperatures, brickwork can be easily erected.

Facial masonry:

Down to minus five degrees, it is possible to produce facing brickwork without using any additives. At low temperatures, without adding such prepared additives, the solution may crumble, especially when the seam was embroidered with a semicircular joint. It is very good to use potash as such an additive, and it is not expensive.

Backfill masonry (rough):

If the temperature drops to minus ten degrees, then backfill masonry is erected. In this case, there is no need to add any special chemical additives, since the strength of the solution will not change. If the temperature drops even lower, then potash is used again.

You can protect mortar and cement from low temperatures in winter in the following ways:

1) Using a warm composition, masonry is produced by freezing;

2) Warm up the masonry artificially, using air heaters, air heating units and other heating devices;

3) You can build a temporary shelter, and also warm it up with heat guns or cover it with PVC insulation and film.

Tips for making cement mixture at subzero temperatures:

• Use hot water to make the solution. You can add high-quality antiphysis to the water;
• It is advisable to prepare sand in advance, storing it in a heated room;
• To avoid cracking of the solution, add potash.

Simple chemical solutions can be easily prepared in a variety of ways at home or at work. Whether you are making a solution from a powder material or diluting a liquid, you can easily determine the correct amount of each component. When preparing chemical solutions, do not forget to use personal protective equipment to avoid damage.

Steps

Calculation of percentages using the formula for weight/volume

1. Define interest content by weight/volume of solution. Percentages show how many parts of a substance are present in one hundred parts of a solution. When applied to chemical solutions, this means that if the concentration is 1 percent, then 100 milliliters of solution contains 1 gram of substance, that is, 1 ml/100 ml.

   • For example, by weight: a 10 percent solution by weight contains 10 grams of the substance dissolved in 100 milliliters of solution.
   • For example, by volume: a 23 percent solution by volume contains 23 milliliters of liquid compound in every 100 milliliters of solution.

2. Determine the volume of solution you want to prepare. To find out the required mass of a substance, you must first determine the final volume of the solution you need. This volume depends on how much solution you will need, how often you will use it, and the stability of the finished solution.

   • If you need to use fresh solution each time, prepare only the amount needed for one use.
   • If the solution retains its properties for a long time, you can prepare a larger quantity for future use.

3. Calculate the number of grams of substance required to prepare the solution. To calculate the number of grams required, use the following formula: number of grams = (percentage required)(volume required/100 ml). In this case, the required percentages are expressed in grams, and the required volume - in milliliters.

   • Example: you need to prepare a 5% NaCl solution with a volume of 500 milliliters.
   • number of grams = (5g)(500ml/100ml) = 25 grams.
   • If NaCl is given as a solution, simply take 25 milliliters of NaCl instead of the number of grams of powder and subtract that volume from the final volume: 25 milliliters of NaCl per 475 milliliters of water.

4. Weigh the substance. After you calculate the required mass of the substance, you should measure this amount. Take a calibrated scale, place the pan on it and set it to zero. Weigh the required amount of substance in grams and pour it.

   • Before continuing to prepare the solution, be sure to clean the scale from any remaining powder.
   • In the example above, you need to weigh out 25 grams of NaCl.

5. Dissolve the substance in the required amount of liquid. Unless otherwise specified, water is used as a solvent. Take a measuring beaker and measure out the required amount of liquid. After this, dissolve the powder material in the liquid.

   • Label the container in which you will store the solution. Clearly indicate the substance and its concentration on it.
   • Example: Dissolve 25 grams of NaCl in 500 milliliters of water to obtain a 5 percent solution.
   • Remember that if you are diluting a liquid substance, to obtain the required amount of water, you must subtract the volume of the added substance from the final volume of the solution: 500 ml - 25 ml = 475 ml water.

   Preparation of molecular solution

   1. Determine the molecular weight of the substance used using the formula. The formula molecular weight (or simply molecular weight) of a compound is written in grams per mole (g/mol) on the side of the bottle. If you can't find the molecular weight on the bottle, look it up online.

      • The molecular weight of a substance is the mass (in grams) of one mole of that substance.
      • Example: The molecular weight of sodium chloride (NaCl) is 58.44 g/mol.

   2. Determine the volume of the required solution in liters. It is very easy to prepare one liter of solution, since its molarity is expressed in moles/liter, but you may need to make more or less than a liter, depending on the purpose of the solution. Use the final volume to calculate the number of grams needed.

      • Example: it is necessary to prepare 50 milliliters of a solution with a mole fraction of NaCl of 0.75.
      • To convert milliliters to liters, divide them by 1000 and get 0.05 liters.

   3. Calculate the number of grams required to prepare the required molecular solution. To do this, use the following formula: number of grams = (required volume)(required molarity)(molecular weight according to the formula). Remember that the required volume is expressed in liters, molarity in moles per liter, and molecular weight according to the formula in grams per mole.

      • Example: If you want to prepare 50 milliliters of a solution with a mole fraction of NaCl of 0.75 (molecular weight according to the formula: 58.44 g/mol), you should calculate the number of grams of NaCl.
      • number of grams = 0.05 L * 0.75 mol/L * 58.44 g/mol = 2.19 grams NaCl.
      • By reducing the units of measurement, you get grams of the substance.

   4. Weigh the substance. Using a properly calibrated scale, weigh out the required amount of substance. Place the pan on the scale and set it to zero before weighing. Add the substance to the bowl until you get the required mass.

      • Clean the scale pan after use.
      • Example: Weigh out 2.19 grams of NaCl.

   5. Dissolve the powder in the required amount of liquid. Unless otherwise noted, most solutions are made using water. In this case, the same volume of liquid is taken that was used to calculate the mass of the substance. Add the substance to the water and stir until completely dissolved.

      • Label the container with the solution. Clearly label the solute and molarity so that the solution can be used later.
      • Example: Using a beaker (an instrument for measuring volume), measure 50 milliliters of water and dissolve 2.19 grams of NaCl in it.
      • Stir the solution until the powder is completely dissolved.

   Diluting solutions of known concentration

   1. Determine the concentration of each solution. When diluting solutions, you need to know the concentration of the original solution and the solution you want to obtain. This method is suitable for diluting concentrated solutions.

      • Example: You need to prepare 75 milliliters of a 1.5 M NaCl solution from a 5 M solution. The original solution has a concentration of 5 M, and you need to dilute it to a concentration of 1.5 M.

   2. Determine the volume of the final solution. You need to find the volume of the solution you want to obtain. You will have to calculate the amount of solution that will be needed to dilute this solution to the required concentration and volume.

      • Example: You need to prepare 75 milliliters of a 1.5 M NaCl solution from a starting solution of 5 M. In this example, the final volume of the solution is 75 milliliters.

Comments:

Until now, not a single construction or repair can be completed without the use of cement. When deciding how to prepare cement mortar, you must first take into account that the one used for brickwork, floor screed or finishing of walls and ceilings can differ significantly both in composition and in the method of preparation.

When making a concrete mixture, cement serves as a binder that ensures its hardening.

Main components of cement mortar

There are two types of mortar - cement and concrete. Despite the similarity in components (concrete, in addition to the three common components, crushed stone or gravel is additionally added) and the method of preparation, these are two completely different products designed to solve different construction problems.

Classic cement mortar consists of only three components mixed together in a certain proportion: cement, sand and water.

The cement must be dry and free of hard lumps. It is best to use river sand, although in practice they often take ordinary sand from a quarry, but first sift it to separate debris and impurities.

To mix the mixture, it is better to use clean water at room temperature or a little warmer - 21-23°C.

The optimal proportions are: 1 part cement to 3 parts sand. Water is added to the cement solution being prepared as needed, its amount can vary from 80 to 95% of the volume of cement used (i.e., 8 to 9.5 liters of water should be consumed per 10 liters of cement).

This solution can be used to both remove brickwork and perform plastering work. However, it has a number of disadvantages - excessive rigidity and limited time (1-1.5 hours) for using the prepared solution, which makes working with it significantly more difficult.

Therefore, professional builders prefer to add various substances to its composition when preparing cement mortar, making it more plastic and prolonging its hardening time by 2-3 times. The most common option for improving such a mixture is adding lime milk to its composition.

This mixture has almost the same astringent abilities as pure cement mortar, but its use time increases to 3-4 hours.

The second option is to prepare a cement solution with the addition of a small amount of detergent - at the rate of 50-100 g for every 10 liters of mixture (depending on the quality of the detergent).

This additive can significantly increase its plasticity.

Return to contents

Brands of solution and their use

The marking of the finished solution does not directly depend on the brand of cement used for its preparation, as most non-professionals mistakenly believe. In fact, a mixture of the same brand can be prepared from different brands of cement.

For example, a mixture of M100 can be obtained from cement M300, M400, M500, and in all cases the amount of cement used for its preparation will be the same. But the amount of sand changes: when using M300 cement, the ratio of sand and cement will be 3:1; when using M400 - 4:1; and when using M500 - 5:1.

When using cement mortar, professional builders advise using a composition of the same brand as the material used for construction. Those. If M75 concrete mortar is used to fill the foundation, then a cement mixture of the same brand must be used to screed the base. If M100 brick is used for forcing the walls, then the mixture for masonry must correspond to this brand.

But in practice this is not always possible. For example, when using M300 brick when laying out walls, there is no point in using a mortar of the same brand to lay it - it is difficult to work with such a mortar, and the financial costs for its production are very high. Brands in the range from M100 to M150 are quite suitable for use. In practice, such masonry is most often performed using a mixture of sand and cement M400 in a ratio of 3.5:1, i.e. approximately M115.

This additive can significantly increase its plasticity.

How to make cement mortar correctly

There are several ways to prepare a high-quality cement mixture. But, regardless of the chosen method, you will need the following tools to prepare it:

• container for mixing components;
• shovel;
• trowel;
• buckets.

The most common classical method of preparing the mixture is to first mix cement and sand dry until a homogeneous composition is obtained, and then this mixture is diluted to the desired consistency with water. Water should not be added all at once, but 80-85% of the required amount, and during the process of preparing the mixture, gradually add it to the composition, achieving the desired thickness.

This rule must be observed especially if it is not a pure cement-sand mixture that is being prepared, but a cement-lime mixture. In this case, you first need to prepare liquid lime by diluting the lime dough with water until it becomes a thin sour cream. Then the solution is prepared in the same way as in the first option, but instead of the missing water, lime milk is added to it at the final stage.

The second method was invented by folk craftsmen to prepare the solution manually. In fact, it is almost a mirror image of the first: first, water is poured into the container (approximately 4/5 of the required amount), then liquid soap or other detergent is added to it. After this, the water must be vigorously shaken for 4-5 minutes so that the detergent is completely dissolved in it and forms the maximum amount of foam.

Then half the required volume of sand and the entire volume of cement are poured into the container. After this, all components are mixed together. Particular care in mixing at this stage is not yet required, the main thing is that the resulting mixture is more or less homogeneous in composition. Then the missing sand is added to the mixture, and here negligence in mixing is unacceptable - you need to knead until the mixture becomes homogeneous. The presence of areas of clean sand without cement is unacceptable.

The main advantage of this method is that in a liquid state, sand and cement mix much faster and better than in a dry state. But in order to properly make a cement solution, at the end of preparation you need to gradually add the missing water, bringing the solution to the desired thickness.

This additive can significantly increase its plasticity.

Little tricks when preparing the solution

Despite the apparent simplicity of the process, even experienced builders are not always able to immediately prepare the cement mortar correctly. Therefore, the prepared solution is divided into 3 types:

• skinny;
• normal;
• fatty.

To determine the type of mixture prepared, no special tools are needed. It is enough to pull out the shovel used for mixing or (in the case of a concrete mixer) stir the finished mixture a little with a trowel. If the working surface of the tool remains almost clean, then the prepared mixture is thin, since it lacks a binder - cement. If the entire surface of the instrument is hidden under a layer of the prepared mixture, then the latter contains too much cement and is greasy.

Only a normal solution is suitable for work, in which the proportions of cement, sand and water are correctly maintained. If the solution turns out to be thin, then you need to add cement to it, and if it is greasy, add sand and water, bringing it to normal. You need to add the components little by little, otherwise it will cost nothing to turn a lean solution into a fatty one and vice versa.

Initially, you should always pour a little less water than normal.

The fact is that its amount depends on the absorbency of the sand - dry sand absorbs much more water than wet sand. Therefore, by pouring it according to the norm and adding slightly damp sand, you risk getting a liquid solution.

Cement is a popular building material used in the process of performing various works. It produces concrete used in the construction or repair of structures, when creating foundations or other objects. It is cement that is the main component for the formation of concrete mortar. Therefore, you need to know exactly how to properly create this mixture so that it has the desired consistency and homogeneity. So, let's look at how to properly dilute cement.

Important! The quality and other parameters of the concrete solution determine the strength, reliability, service life and resistance of the resulting structures to various influences.

Features of using cement

Cement is a special adhesive substance used to create various mixtures or solutions. The most commonly produced concrete solution contains the following components:

• suitable brand of cement;
• pure water;
• various fillers, which can be sand or crushed stone.

The amount of mortar, the quality of the components and their proportions completely depend on the purpose for which the mixture is being created, since it can be used for laying walls or for plastering them (than plastering aerated concrete). It is used for pouring foundations or other similar purposes.

Basic rules for creating a high-quality solution

The basic rules used in the process of creating a high-quality mixture include:

• it is allowed to mix the components and fill them with water in a metal or plastic container;
• the size of the container depends on the volume of solution that needs to be obtained in the end;
• Initially, the dry components are mixed, namely sand and cement, and they must be sifted through a fine sieve in advance so that they are completely free of any large impurities or inclusions;
• Next, clean water is added to this mixture, and it is desirable that it be cold;
• while adding water, the mixture must be thoroughly mixed to obtain an optimal consistency, similar to sour cream;
• It is quite easy to determine the desired thickness, since the mixture must stay on the spatula, and at the same time it must not flow from it.

Important! If dirty sand is used, then before use it is necessary to soak it in water, after which it is mixed well, the water is drained and the sand is dried.

The resulting solution has optimal parameters for an hour and a half, so it is necessary to use it for its intended purpose within this time, and if this does not work, then you will have to make a new mixture.

In what proportions should cement be diluted?

The correct proportions can vary significantly between different mixtures. Therefore, before mixing, it is necessary to decide for what purposes a particular solution will be used.

Important! The consistency of the solution changes depending on the proportions of the components.

The most popular mortars that require cement are:

• Mixture for plastering walls. To prepare it, it is recommended to use 1 part cement and 3 parts sand. The volume of water is usually equal to part of the cement, but it cannot be added immediately, so it is poured into the dry mixture in small portions to obtain the desired consistency. If you need to carry out internal plastering work, then the M150 or M200 grades are selected, and if you plan to plaster the facade, then the M300 grade is suitable.
• Brick masonry mortar. Here we use 1 part cement and 4 parts sand. The optimal brands for this work are considered to be M300 and M400. Often slaked lime is added to this mixture, acting as a binder. Its amount is calculated as 0.2 parts per 1 part cement. This substance produces a plastic solution, which is quite easy and convenient to work with. The amount of water may vary, as it is added gradually until a solution of the desired density is obtained. It is important to make a mixture that will not flow from the spatula, tilted at an angle of 40 degrees.

• A mixture designed to create a floor screed. Typically the following proportions are used: 1 part cement to three parts sand. The M400 brand is considered optimal. Water is added in a volume of ½ the amount of cement. To make a rare solution, it is recommended to gradually add water, as it is important that the mixture stretches well, which ensures that all voids in the base are filled.
• Concrete. To create concrete, use 1 part cement, 2 parts sand and 4 parts gravel. If this solution is made to form the foundation of a building, then it is necessary to purchase material grade M500. The amount of water is equal to ½ of the cement. The water must be clean and potable, and it is recommended to mix the composition with a concrete mixer (how to choose a concrete mixer for your home and garden). The entire solution must be used within an hour after receiving it.

Important! If you want to get a mixture in sufficient quantity to form the foundation of a building, then you will need a fairly large amount of it, for which special equipment is used, represented by a concrete mixer.

Often, ready-made solutions are purchased at the factory, and in this case you need to make sure that the mixture is created immediately before sending it to the customer. Before purchasing, we study all the documents for the mixture in order to know what components it consists of, as well as what parameters it has.

It is necessary to choose the right grades of material to form different solutions. If the mixture is intended to create brickwork, then you can use grades M50 or M100, and if you need to make a foundation, then it is advisable to choose grades from M300 to M500. The higher the grade of material, the more durable and reliable the solution will be.

Video: how to properly mix cement mortar

Cement can be diluted with different components, and their quantity and purpose depend on the purpose for which the final solution will be used. It is important to use only high-quality and clean materials, and to mix them in the correct sequence. It is recommended to use a concrete mixer or construction mixer for mixing, since manual mixing does not ensure uniform distribution of all components. If you correctly follow all recommendations, you are guaranteed to obtain a high-quality and optimal solution for specific purposes. That's all, we hope this article - “How to properly dilute cement” was useful to you.