The most durable concrete. Concrete in Siberia is more than concrete: how to make money on decorations made from building materials The strongest brand of concrete

Behind long years In construction practice, people have never found a more durable, practical, durable material than concrete. It consists of a mixture of cement, sand, water, and crushed stone.

Also, modern builders add special strengthening additives to the solution, which make the material almost eternal, indestructible, and as durable as possible. However, when making a concrete mixture, the proportions of all components must be strictly observed. Otherwise, foundation, reinforced concrete wall multi-storey building, ground floor, located underground will not be durable. The material will crack, will go out of service ahead of time, and dangerous situations will be created. So what mistakes in concrete production negatively affect the quality of finished products?

The most important mistakes

It should be noted right away that concrete mixtures can be prepared in different ways. Everything will depend on what building construction need to be made from the resulting mixture. The most important mistake is the incorrect use of cement dosage. Excess or underestimation of this component completely affects the finished structure. You also need to clearly consider what brand of cement to use before placing it in the future solution.

Note! For the construction of reinforced concrete structures that will be used underwater, the strongest, most expensive brand of cement is used. For simple structures used outdoors, it is permissible to add a low grade of inexpensive cement to the solution.

Another very important mistake is the lack of high-quality mixing of the solution when producing large batches of cement.

• Good mixing is one of the most important components in the production of concrete on an industrial scale;
• Under no circumstances should you use dirty fillers, unsifted sand, or interspersed with pieces of clay. All this leads to a poorly manufactured solution, which will be very poor in finished products;
• Also cannot be used dirty water. The liquid must be cleaned before mixing occurs. The water is purified from mud, pieces of clay, and all kinds of biological pollutants;
• Under no circumstances should cement powder be used after long-term storage.

And you need to be very careful to ensure that there is no overdose of various types of strengthening additives that are added to the reinforced concrete mortar.

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Siberian Marina Selivanova chose design as her profession - after two specialized higher educations she worked in interiors, advertising, event design, food design, etc. But one day the idea came to her about making jewelry, and not from traditional materials, and from... concrete. About how in demand accessories from building material and what are the nuances of their production, Marina Selivanova told the portal site.

29 years old, entrepreneur from Novosibirsk, founder of a brand of concrete jewelry. Graduated from the Yenisei Pedagogical College (specialty “teacher of fine arts and drawing”) and Novosibirsk State University architecture, design and art (specialty “designer”). The accessories brand was launched in 2016. Single.

Combine the incongruous

When I figured out my higher education, then worked for six months in the field of interior design and graphic design. Now I still continue to receive such orders: I make business cards, banners. I also do food design and design events.

I didn’t have a goal to start making jewelry - just one day, as part of my design work (as well as the renovation of my apartment), I somehow took a new look at concrete. I liked its texture - uneven, interesting; In my apartment, I even left one wall concrete, without finishing. I decided that concrete could make something truly stylish and beautiful.

When it comes to concrete, many people immediately think of something massive and heavy. I wanted to make something light, small and unusual from this material. This is how I came to jewelry. In general, I really like this concept: comparing the incomparable, combining the incompatible. Concrete with gold is interesting. Many masters work with minerals, semi-precious stones, but it’s great to find something of your own, your own style. A person carries himself in his work.

In my jewelry, I combine concrete with acrylic, copper, gold and silver leaf; I also use pigments in the concrete itself (in particular, black).

My brand Haf Maer has no translation. I had no intention of tying the name to anything. So I came up with this - simple and sonorous, a little reminiscent of Scandinavian motifs and Vikings. Besides, I didn’t come across such a name in hashtags on Instagram.

Sand in the art salon, cement in the construction store

Acquaintance with working tools occurred gradually. The first thing I bought was this sanding paper, needle files, files, then a grinding machine (which I don’t use now, since it is large and inconvenient for grinding small parts).

At first I worked without protective equipment, but later I realized: this is not worth saving on. I bought additional gloves, a respirator and special glasses. My dad gave me the drill. That is, I only needed 10 thousand rubles to start.

To begin with, I just started trying to work with a material that was new to me and poured concrete into some kind of cream lid. As planned, it was supposed to be a pendant. It turned out to be very large - 10 cm wide. I drilled a hole in it and that’s how I got my first pendant. Now, however, I don’t know where she is. But I would like to find and compare with current products: progress, I think, would be obvious.

It took me a lot of time to understand what components were needed for my author’s composition of the material. The fact is that I developed the technology for my concrete myself; it is not similar to construction concrete. I needed the material to become denser and harder. The concrete used for construction would crumble in my jewelry—especially the miniature pieces. It also absorbs moisture.

After six months of experimentation, I managed to develop a suitable recipe for my concrete. I won’t reveal the entire composition, but there is sand and cement (these are, in general, the main components of concrete).

I take pigmented, black sand, buy it in art salons and hand-made stores. I buy regular cement, in a 15 kg bag, at a hardware store. This amount is enough for a year. It’s unlikely that the sellers think that I need this bag for dozens of earrings and pendants, and not for repairs.

As a result, my jewelry, of course, can last a long time, thanks to the special composition of concrete. Unless you try really hard, it's hard to break them.

In the fight against allergies

In addition to concrete, production also requires forms for it - to make different elements of decoration and connect them. I either buy the forms or make them myself if I don’t find suitable ones on sale. They are filled with a composition that hardens within 24 hours. Thus, a simple decoration consisting only of concrete takes 24 hours to make. Complex decoration requires two days.

After hardening, the product must be processed engravers, grinding machines, drills and drill bits.This is a very dusty job, I do it on a separate table - so that concrete particles from grinding do not fall on those decorations that are currently in the process of drying.

We still need fittings. Today I have it not made of precious metals, it is a jewelry alloy. But now I'm switching to surgical steel, which does not cause allergies. In the process of working as part of the Haf Maer project, I was faced with the fact that many of us cannot wear costume jewelry due to allergies. There are big problems with fittings in Russia in general - you can’t really let your imagination run wild if you want some interesting additions to concrete (and I would like this in many models).

Usually accessories for jewelry self made They order from China, but the quality there leaves much to be desired. Good suppliers in Korea and the USA. My new supplier for surgical steel is from Russia. It also cannot offer a wide selection of shapes of clasps, chains, etc. - but in in this case For me, of course, hypoallergenicity is a priority.

Looking for clients

I started in my apartment, but for the last month I have been working in a workshop. We are filming it together with a friend who sews bags. Between us we have 30 square meters, and since there are no other employees besides ourselves, this is enough for now. We also have one individual entrepreneur for two. Today, working with Haf Maer takes up 50% of my time.

For sales, the first thing I did, of course, was create Instagram page. At first I just gave my jewelry as a gift. Including, when I worked as a designer at some events, I made presents for guests from it. Then I gave a few pieces by barter to small bloggers: that is, I give them jewelry, and as a return courtesy, they write about my brand in their profiles. So big money I haven’t invested in my promotion yet. I also participated in markets in Novosibirsk, where I presented my products and gradually met new clients.

And then, towards the end of 2018, girls themselves began to contact me. Now in the city I am already better known as a jewelry designer than as a designer of anything else. My target audience is women 20-40 years old; they are united only by some kind of affiliation or commitment to creativity and style. By the way, such a range in age surprised me: I was more likely counting on young people.

The most interesting and at the same time difficult order for me were earrings for my mother for her anniversary. She doesn’t have pierced ears, so I specially made clips (so now we have this option in our line). As a result, the earrings suit her very well, and I was once again convinced of how jewelry can transform a woman.

I’m also especially interested when, for example, a girl wants asymmetrical earrings. And together we look for shapes that will go well together and put together a set.

Often people don’t even pay attention to the fact that my jewelry contains concrete. For them it is paramount general form decorations. It’s funny that the last time a girl who works in a hardware store ordered a ring from me, I was very intrigued by its composition.

A year ago I was selling a couple of pieces of jewelry a month. Today I sell 15-20 per month. And on the market I can sell 15-20 pieces in one day. The cost of my jewelry is 1-2 thousand rubles. I am sure that sales will grow and this business will bring me significant income.

Today my jewelry is sold in Moscow (in a showroom with clothes and accessories), Yaroslavl (in a beauty salon) and Irkutsk (in the Bonstein Gallery). They found me themselves, which is interesting, and offered to collaborate. But mostly my sales are on the Internet and in two Novosibirsk points (a showroom and an art space).

Basically, I work to order using models that I have already developed. I usually don’t take completely custom orders. The difficulty is that then in each case you will have to make a separate mold (and people are usually not willing to wait an extra week). Plus it’s irrational - then you don’t know what to do with all these forms.

At some point I began to wonder if someone somewhere was creating similar jewelry. I found those who make decorative items from concrete (pots, stands, etc.) - including those who also make jewelry. But they work with regular gray concrete, and the style is completely different. I wouldn’t want to scale my project this way in the future. Rather, I will come up with some other unusual material.

My competitors are other masters who work with the most different materials. For example, in Krasnoyarsk a girl pours jewelry out of epoxy resin, they are also made of wood, etc. I began to notice that sometimes they even take jewelry models from me and repeat them. I haven’t thought about a patent yet, but it’s probably worth doing one.

In the future, I would like to open something like a showroom-workshop. I would also like to switch to jewelry metal (silver).

I’m unlikely to ever have million-dollar sales, since concrete is a specific material. However, the potential is there. So I plan to invest in advertising. There is an intention to expand the number of its representatives in other cities.

I like to create new things and the fact that you can put an “equal” sign between my business and me: concept, idea, brand philosophy H af Ma er is me. And there are people who understand and appreciate this. This is why I continue.

How to make strong concrete (concrete mortar) with your own hands.

Mortars and concretes are man-made stone materials that are produced by mixing a binder (usually lime and Portland cement) and certain aggregates. When mixed with water, the binder forms a stone-like body, which is explained by the processes of setting and rapid hardening. The strength of the stone-like body is ensured by the filler (gravel, crushed stone, sand). Next, I will tell you about all the stages of the question of how to make concrete with your own hands.

Components for making the solution

1. Filler

For mortar, most often, fine sand or other fine aggregate is taken. For concrete mortar, you can take not only fine sand, but also coarse gravel or crushed stone. To make construction plaster or masonry mortar, it is best to use fine sand, the grains of which do not exceed 2 millimeters in diameter. If the plaster has a special texture, it is possible to add sand with a grain size of up to 4 millimeters. In our market, customers are offered two types of sand: river and ravine. River sand is considered medium-grained, it is quite expensive, but its purity facilitates its use as a component for concrete mixtures. Gully sand can be fine-grained (from 0.5 to 1.5 millimeters), with a large number of clay particles and other impurities. It is not suitable for good and strong concrete, but for mortars it can be used without fear.

For lean (light) cement concrete with strength class B7.5, only sand can be used as a filler. In concrete of greater strength, in addition to sand, you can also use crushed stone or gravel with a diameter of up to 31.5 millimeters. It is considered correct to use a crushed stone mixture of different fractions so that the finished concrete contains a minimum amount of voids between the stones.

Attention! The aggregate of concrete and mortars should not contain pollutants such as soil, glass, pieces of wood, peat, plants, dusty or silty soil. If contaminants are present, they should be removed by sifting gravel or sand through a sieve.

2. Cement

Cement is a general name for binding powdery substances based on marly, calcareous and clayey rocks and various additives. The most commonly used type of cement is Portland cement, which takes its name from the British peninsula of Portland. This cement contains a large amount of calcium silicates. Under construction country house Two types of Portland cement can be used.

Type I – does not contain additives, or their content does not exceed 5 percent. The European classification for such cement indicates the name CEM I.

IN Russian practice the presence of cement additives is indicated by the letter D and a number in the marking code that follows the brand. For example, if you see the marking PC 500-D20, then it means the presence of 20 percent of additives in grade 500 Portland cement. As we have already found out, this characterizes type II cement. As for the DO designation, it characterizes type I cement, that is, a material without additives.

To prepare plaster and masonry mortar, you need to take cement of classes M400 (32.5) and M500 (42.5). Portland cement is ideal for preparing concrete mixtures that will be used at low temperatures (daily average below 10 degrees Celsius). If the temperature is high, for example, in the heat, then it is better to use Portland slag cement or type III cement (the European classification indicates the name CEM III). It is well suited for the manufacture of masonry and plaster mortars used for fencing and flooring.

Attention! Cement can only be purchased in bags with appropriate markings. Immediately before purchasing, you need to check whether the cement is damp or caked. If all the signs are present, it is recommended to refuse the purchase. Only a trusted, reputable manufacturer who has been selling the solution for several years can guarantee compliance with the brand of cement stated on the packaging or bag. By the way, the main difference good manufacturer What makes it underground is not the cost of ready-mixed concrete, but the availability of a high-quality delivery service.

3. Lime

Lime is required for the production of cement-lime mortars. In addition, it is used to increase the workability of the solution. Today, to prepare solutions, it is no longer necessary to slak lime. Instead, you can buy slaked (hydrated) fluffed lime at a low price, which is sold packaged in bags in ready-made form. Alternatively, instead of a dry mixture, lime can be sold in buckets in the form of lime paste. It is added to cement-lime plaster and masonry mortars to improve their workability.

Attention! If you decide to use lime as part of the question of how to make concrete at home, be extremely careful, since lime has strong corrosive properties. It is recommended to carry out work wearing protective gloves, remembering to ensure that the material does not get into your eyes or skin. The same applies to the use of dyes, as well as subsequent work on grinding and polishing the product.

4. Additives

The composition of a concrete mixture or mortar may contain certain additives that can either improve or simply change their certain properties.

Plasticizers or plasticizing additives can increase the fluidity of the mixture, as a result of which builders receive a solution with a more liquid consistency. This solution is much easier to apply.
Thinning additives or superplasticizers can reduce the amount of water poured for mixing.

In addition, their use makes it possible to improve the workability of the mixture, increase the strength, frost resistance and water resistance of the mortar or concrete.

Certain additives allow you to accelerate the hardening of a concrete mixture or solution.

Also, there are additives with which it becomes possible to carry out work in the temperature range from 10 degrees below zero to 35 degrees hot.

There are special additives on the market that slow down the hardening of the concrete mixture, which is useful when concreting in hot conditions.

Air-entraining or aerating additives increase frost resistance and reduce the moisture capacity of the solution in the hardened state.

Typically, supplements are sold in plastic packaging in liquid form. The packaging must contain information about dosage, quantity and basic properties. Additives in mass ratio should not exceed 2 percent of the total mass of cement.

5. Water

The quality of water used for mortars and concretes is regulated by GOST standards. In particular, water must meet drinking standards and must not contain foreign impurities, including sugar, oil, alkalis and acids. It is prohibited to use poorly cleaned swamp and wastewater. It is better to be guided by the principle that you can use any drinkable water to stir the solution. If you prepare a concrete solution using water from a lake or river, you will have to check the suitability of such water in a special construction laboratory.

Composition and proportions

Before you start considering the question of how to prepare concrete or reinforced concrete, I would like to draw your attention to the fact that the composition and proportions will directly depend on its main purpose. That is, for the foundation it is correct to use strong, high-density concrete, while for pouring the fence you can choose lighter grades. Once you have decided on the ingredients, choose the right brand. In most cases, for imported concrete and mortars created by yourself, it is better to choose grades M300 or M400. As for proportions, the components “cement/sand/crushed stone” should be used in proportions of 1/3/5. This means that per cube of concrete, one part of cement requires the addition of three parts of sand and five parts of crushed stone or gravel. If we talk about water, then its amount should be half the weight of other fillers. For example, if you have 100 kilograms of dry mixture, then you need to take 50 liters of water.

If you get too thick (dense) mixture, you can add a little more water. The consistency should be such that you do not need to exert much effort to stir the solution with a shovel. For wet sand there should be less water. If work is carried out in the cold, the water and concrete must be heated, which will protect the composition from premature setting and loss of strength. For work, it is better to use a purchased concrete mixer or devices/mixers and containers made by yourself. You can read what material and what components they consist of (pumps, molds, vibrating screeds, etc.) in another article.

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Concrete mixtures belong to the category of the most used materials in construction. This entails permanent job to improve the composite composition and the quality of its components. Several years ago, the category of especially durable artificial stones included materials of class B30, but today this situation has changed in the most dramatic way.

Modern high-strength concrete in its characteristics and technological properties differs significantly from classical mixtures for the production of concrete stone. Its parameters differ not only in strength, but also in a number of other characteristics. However, today there are several various types high-strength composite materials used in .

Also in Soviet time the standard range of building materials provided for the possibility of producing high-strength concrete of the corresponding classes from B40 to B60. They were used in the construction of especially critical structures and elements of bridges, dams, railway sleepers and others. However, the distinctive characteristic of these compositions was their high rigidity and low ability for high-quality installation.

Modern composite mixtures of increased strength not only differ high resistance to mechanical and weight loads, but also an excellent level of manufacturability when laid in a monolithic structure. Very good mobility and the ability of materials to self-compact make it possible to eliminate the use of vibration equipment and reduce required amount workers for construction site.

The ability of heavy-duty concrete to self-compact during placement

When obtaining new types of concrete, manufacturers of building materials receive a unique structure artificial stone thanks to the use of continuous granulometry technology for all components.

Precisely selected fractions of fillers no larger than 20 mm in size and specially processed to obtain a special shape make it possible to obtain a special active structure of the material, capable of flowing and compacting under own weight. Due to these properties, such mixtures received the general name of self-compacting concrete (SCC).

The combination of high-quality thin floor Portland cements, active mineral additives and fine processed fillers ensures that the installation system remains as stable and easy to use as possible. However, it should be noted that the selection and sorting of the constituent components is quite complex in technological terms. Therefore, such balanced systems are quite expensive and are used only after an appropriate economic justification.

Technology for preparing composite compositions

It is used for the construction of bridge spans long length, reducing the number of load-bearing supports and speeding up the project completion time. The use of new composite materials is usually aimed at solving complex engineering problems and is rarely found in traditional construction methods.

Video review of the material

Concrete is the most popular building material. It is very durable, does not burn, and is not susceptible to destruction by mold and mildew. Over time, properly made concrete only becomes stronger. Concrete is a very environmentally friendly material, as it consists of 100% natural components - sand, water, crushed stone (crushed stone) and cement (specially burnt and finely ground lime). Only in the rarest cases is construction done without concrete, and then only in those cases when it is not possible to prepare it.

Strength grades. Composition of concrete.

What is a strength grade for any building materials (concrete, mortar, brick, etc.) - this is the maximum load that the material can withstand per square centimeter.

If, for example, the brand of brick is 200, then this brick can withstand 200 kg per square centimeter. The surface area of ​​the brick is 300 cm2. This means that one brick can withstand 300 cm2 200 kg = 60,000 kg.

In general, the strength of concrete is a rather variable parameter, and during the entire hardening process it increases. For example: after three days - there will be one strength, in a week - another (up to 70% of the design, under appropriate weather conditions). After a standard period of 28 days of normal hardening, the design (calculated) strength is achieved. Well, after six months it becomes even higher. In principle, concrete hardens and gains strength over many years.

Concrete grade M100.

To prepare concrete M100 you need:

• 1 bucket of cement grade 400
• 3 buckets of sand.
• 6 buckets of crushed stone (limestone), fraction 35.

Mainly used for grillage (foundation base) in the ground.

Concrete grade M200.

• 1 bucket of cement M 400.
• 2 buckets of sand.
• 5 buckets of crushed stone (from limestone), fraction 35.

We use for the manufacture of load-bearing lintels, purlins, reinforced belts around the perimeter of the building, blind areas, reinforced concrete floors, and fill brick columns with concrete inside.

Why does concrete burst?

Very often the concrete surface bursts in finished products (screeds, reinforced concrete lintels, reinforced concrete belts, etc.) when setting. This happens for several reasons and the most basic, inaccurate formula for concrete is:

Much water

Theoretically, there is a strict formula for how much water needs to be poured to prepare concrete. If you pour too much water into concrete, it will delaminate, become airy (there will be a lot of air bubbles in the concrete) and lose some of its load-bearing capacity.

When you fill liquid concrete, then cement laitance (astringent) usually leaks out and it slightly loses its load-bearing capacity.

The best concrete is very thick. Thanks to a vibrator or vibrating table, it is compacted, the pebbles in the concrete (crushed stone) fit as close to each other as possible. During the construction of nuclear power plants, water should never be added to imported concrete; this is strictly monitored.

Thick concrete

This kind of concrete is quite difficult to make and properly lay in “makeshift” conditions on a construction site.

We usually make concrete in a concrete mixer, neither thick nor liquid. When we place concrete into a product, we use a tamper or a vibrator or a regular stick.

To build a private house (compared to a nuclear power plant), there is no need to be too painstaking about concrete.

Even if here I write out the exact formula for adding the required amount of water to concrete, the first rain will wet the sand and this formula will no longer work correctly, since the sand is wet, the concrete will turn out to be too liquid. Sometimes they also bring wet crushed stone.

The exact formula for adding water to concrete is mainly used in production, where the materials are under cover and have relatively uniform humidity.

So: it is best to navigate by cement. That is, if you add one bucket of cement to the mixer, then there is slightly less water than a bucket. There's less to see after the rain. Ideally, the result should be slightly thick concrete.

If, for example, you make a reinforced concrete screed that is too liquid, it will definitely sink a few mm to the bottom and burst:

Why does a reinforced concrete screed burst?

This happens because the concrete delaminates - the heavy filler (crushed stone) goes to the bottom, and the lighter filler (sand) goes to the top. It turns out that there is too much sand on the surface of the screed, and a sand screed without a mesh and plasticizer will certainly burst.

If there is too much water in concrete, then the surfaces of almost all reinforced concrete products will burst.

If, for example, after a few hours you find cracks on the surface of the concrete, then do not be too upset; as long as the concrete is fresh, you can smooth out the cracks with a trowel.

Not enough coarse filler (crushed stone)

The fact is that if you know the formula for the brand of concrete you need, you successfully pour the concrete, but after some time the quality of the concrete is not the same. For example, in one place the concrete surface is perfect and in another it is cracked.

This can happen if you first used large crushed stone, and then small ones!

Very often, cracks on the surface of concrete can appear if you were brought too small crushed stone (or with garbage). Then it is necessary to pour more crushed stone (fine) and less sand. For example, pour more crushed stone into one bucket, and one bucket less sand.

The concrete must be “hard,” that is, there must be as much mortar in the concrete as needed to envelop each crushed stone (pebble).

If there is little solution (cement and sand) in the concrete, then the crushed stone will not be completely enveloped and the concrete will be weak.

If there is too much mortar in the concrete, its surface will burst (tear). Visually, concrete should not be “greasy” from large quantity solution in it.

Therefore, even if you know the exact formula of concrete, you must ensure that the concrete contains the maximum amount of crushed stone and that it is “hard”.

Scorching sun rays.

It is not advisable for the scorching rays of the sun to fall on poured reinforced concrete products for a long time. If it is too hot and dry, the surface of the concrete may crack from drying too quickly. Concrete should set under normal conditions.

If you cannot avoid the scorching sun, then it is enough to simply water the concrete more often.

Poorly mixed concrete.

It is also important to completely mix the concrete mixture in a concrete mixer. To ensure that the concrete does not stick and is quickly mixed in the mixer, it is necessary to follow the order in which the materials are loaded into it.

First, pour water into the concrete mixer, but not completely, but slightly less than normal. Then we throw half the amount of crushed stone into the concrete mixer, then all the cement. We’ll wait a little and throw in all the sand.

At the end we throw in the remaining half of the crushed stone. Wait a few seconds and, if necessary, add the rest of the water.

Due to the fact that we throw the cement after the crushed stone and water, it will not stick and mixes well with the crushed stone.

For clarity, let’s look again at the supply of materials to a concrete mixer for preparing a concrete mixture. To make concrete quickly and without it sticking in a concrete mixer you need to:

• Pour almost the entire amount of water into the concrete mixer (just add a little).
• We throw half the amount of crushed stone into a concrete mixer (a little more is possible).
• We fill in all the cement.
• We throw in all the sand.
• We fill in the remaining half of the crushed stone.
• If necessary, add the rest of the water a little at a time.

The sand is of poor quality.

If you use sand that contains too much clay, this will adversely affect the quality of the concrete.

Too much cement

If you put too much cement in the concrete mixture, it may break as the concrete sets.

Freezing

Oddly enough, no matter how high the grade of concrete, it is very afraid of frost (without special additives).

For example, they made a blind area around the house in late autumn. The weather is damp and cool. The concrete set slowly. Two weeks later there were frosts for a couple of nights.

The next year in the spring, the blind area began to peel off (peel off). The frozen blind area burst and upper layer(30 mm) peeled off.

Complete setting of concrete (almost 100%) under normal conditions occurs after 28 days. That is, if you poured a reinforced concrete slab, you can install it earlier, but it will only be able to bear the design load after 28 days.

In cold times (winter), concrete can be protected from freezing in several ways:

• Cover concrete products with foam plastic or other insulation.
• Add special additives (anti-freeze).
• The most effective way to prevent concrete from freezing is potash.

  Instructions for using potash should be on the packaging.

You can speed up the setting of concrete by heating it. To do this, we place in a concrete product (for example, a reinforced reinforced concrete belt) tungsten filament braided and connected to the transformer.

Another way to warm up concrete is to insert electrodes into a concrete product (fresh concrete), for example a reinforced concrete floor, and connect the electrodes to a transformer or welding machine.

As long as the concrete has moisture, electricity and therefore heat will pass through it. The heated concrete will set, the moisture will disappear, the transformer ( welding machine) will stop working.

We choose the right materials for making concrete.

The water should theoretically be clean. To prepare concrete, it is not advisable to use rainwater, greasy water, or water containing oils (for example, an oil water barrel).

Most the best option for the production of critical concrete (load-bearing lintels, reinforced concrete floors, etc.), use clean tap water.

For the manufacture of screeds and the like (non-responsible concrete) can be used and not entirely clean water for example: water from rivers, lakes, rain and the like.

Very often we use water from wells and wells to make concrete - good results.

Crushed stone

Most often for the production of concrete we use crushed stone - limestone, fraction 20 - 35. Limestone is not a bad material and is also the cheapest in our area.

To increase the strength of concrete, you can use stronger crushed stone, for example dolomite or granite. But as practice shows, granite is more often phonite (the background radiation is exceeded).

Types of crushed stone fraction:

Cement

Most often, we use grade 400 cement to prepare concrete. Almost all cement manufacturing plants produce cement of the same brand, but unfortunately the quality is different for everyone (as practice shows).

You will find a detailed description of some cement manufacturers, which cement is better and which one is not worth buying here.

Most often we use Balakleyevsky cement M 400 marked ShPTs ӏӏ/B-Sh-400.

Sand

Theoretically the most best sand- this is a career one. Since the grains of sand are irregular in shape (rougher), the adhesion area of ​​the sand is correspondingly higher. River sand (sea sand) has a smoother grain shape compared to quarry sand.

A serious disadvantage of quarry sand is the presence of clay! For example, our quarry sand is mined by washing. That is, sand is washed out from the depths and supplied to the surface through a pipe (such as a dredge). In such alluvial sand, clay comes across a few layers.

River sand is also not always ideal; there is clay.

Usually we remember that there is more clay in such and such a quarry, but it is cheaper, then we use it for backfilling or in non-critical concrete.

Or in another quarry there are a lot of small stones in the sand, but no clay, then we use it to prepare concrete. Since there are many small stones in the sand, the solution (for brickwork) we do not order it (or sow it through a sieve, if necessary).

Myths of concrete steaming

There is a myth that steamed concrete products (cinder block, euro fence, etc.) have increased strength.

Manufacturers of steamed concrete products tell developers that steaming makes their products stronger than their competitors and increases the price.

Unfortunately, steaming does not increase the strength of concrete (well, the maximum is 0.5%). The only and main task of steaming concrete products is to accelerate the setting of concrete.

You may ask, why then increase the cost of a durable camera?

Just for example:

• Release the form faster (remove the form).
• Do not increase the size of storage facilities (in which concrete products will mature).
• Sell ​​concrete products faster, and the like.

Steaming concrete products speeds up their setting by approximately two times. That is, for example concrete block under normal conditions, it takes 28 days to acquire almost 100% strength, then a steamed block will gain almost 100% in 15 days.

Summary: steamed concrete is practically no different from ordinary concrete that has matured under NORMAL CONDITIONS!

Normal conditions for concrete ripening are:

• So that the concrete does not dry out (from the scorching rays of the sun).
• To prevent concrete from freezing (without antifreeze additives).
• For concrete to mature at temperatures from +5 ˚С to + 25 ˚С

Technical characteristics of concrete.

A little about the weight of concrete. This information will be useful to you during the manufacture of concrete formwork. Concrete is heavy, so when making formwork for concrete, care must be taken to ensure that the formwork can support the weight of the concrete.

One m3 of concrete weighs from 0.5 to 2.5 tons, depending on the filler. The weight of any material is calculated thanks to its density. Concrete density ρ (ro) from 0.5 t/m3 to 2.5 t/m3. We multiply one m3 of concrete by density (rho) and get the weight of concrete.

1 m3 of ordinary concrete weighs about 2.2 tons.

If you are making ceiling formwork (for concrete), then it will be very easy for you to calculate how much kilogram of pressure per m2 of formwork. For example, you just need to multiply one by the thickness of the concrete and the density of the concrete (2.2 tons): 1 (m2) 0.2 m (thickness of the concrete ceiling) 2.2 t = 0.44 t (or 440 kg).

One m2 of formwork is pressed by 200 mm thick concrete weighing 440 kg.

Summary: as you can see, concrete weighs quite a lot, so when making formwork (for concrete), you should not skimp on materials, so as not to redo it later.

Composition of concrete for construction small house:

• Concrete of two grades: M 100 for grillage and M 200 for other reinforced concrete products.
• The composition of the concrete is not very thick, with a maximum amount of crushed stone, from good cement And good fillers.
• Create normal conditions for the maturation of concrete (to make it durable and of high quality).
• Do not steam concrete (unless there is a need to accelerate the setting of concrete).
• When making formwork, first calculate the weight of the concrete product so that the formwork does not get crushed.

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Preparation of concrete for the foundation

• Concrete selection
• Preparing the mixture
• Quantity calculation

The foundation is the basis for any building. It must be strong enough to support the weight of the building. The foundation can be strip, pile, columnar or tiled.

Types of foundation: strip, columnar, monolithic, pile, slab, floating, screw.

Concrete as a building material will be the best choice.

This foundation is suitable for any type of house, even if it has a basement. In order for the foundation of the house to be strong, it is necessary to choose the right concrete for the foundation.

Concrete selection

Concrete classification scheme by grade.

Everyone knows that concrete comes in different types. The strength of the entire building will depend on the type of mixture. The grade of concrete for the foundation of a house is what people pay attention to first. The most common brands:

• M 400 is the most durable concrete. It can be used for the construction of structures that will have to withstand enormous loads. These are, for example, bridges, hydraulic structures, industrial enterprises. This class of concrete contains plasticizers and granite;
• M350 – has slightly less strength than M400. Mainly used in the construction of residential multi-storey buildings;
• M250 - used for the construction of wooden houses, staircases, floors with light loads;
• M200 is the most versatile brand. Strip foundations are most often made from such concrete.

To choose concrete for the foundation, you also need to pay attention to the soil. If the soil is highly resistant to moisture (sandy or granite), then grade W-2 is quite suitable. The problem arises if the house is built on clay soil. Clay in winter time freezes and increases significantly in volume. If the concrete is laid shallow under the foundation, it may rise slightly. Moreover, it will rise unevenly, depending on how much the clayey areas of the earth are saturated with water. To prevent this from happening, it is necessary to lay concrete on the foundation as deep as possible so that its level is below the freezing level of the clay. In this case, ready-mixed concrete for the home needs to be taken of a higher grade.

http://youtu.be/VZLZd7yKa2A

Another important factor influencing the choice of concrete grade will be the type of foundation itself. In this case, the choice depends on the availability in the house basement. Commercial grade concrete for a home with a basement must be waterproof. You may even have to organize additional external insulation from moisture. There are several options for getting out of this situation:

• you can buy any suitable concrete, which does not necessarily have waterproofing properties. And make external insulation using roll or coating products. This is a relatively cheap option;
• you can take the middle class of concrete, mixing it with additional impregnation. This is a rather dangerous option. Only professionals should do this kind of work. No one can say for sure what the result will be in this case. Perhaps the foundation will be strong, or, for example, a wall collapse may occur;
• The third way is to simply use high-quality grades of concrete for foundations that have waterproof properties. This class of concrete sets easily and quickly and is laid well. You will have to spend money on building material, but there should be no problems;
• The fourth method is the use of special waterproofing concrete compositions with various additives that increase protection against moisture.

Read also: The influence of liquid glass on the properties of cement mortar

If you have to lay a foundation in a fairly aggressive environment, that is, where there is a huge amount of salts and other chemicals in the soil, then you need to pay attention to sulfate-resistant concrete. Finding this class of building material will be difficult, since stores mainly sell only ordinary ones. If possible, you can make a special order at the factory. Sulfate-resistant concrete for foundations is produced in very limited quantities. Often you have to cope on your own and add additional additives to the mixture.

Preparing the mixture

Proportions of cement consumption for bricklaying.

The required brand of concrete can be purchased at any hardware store. After selecting the foundation mixture of the desired brand, you can begin making the solution. This can be done without professional help. If you follow the instructions exactly, the foundation will be strong and the house will stand on it for centuries.

To work you will need:

• concrete mixer;
• sand;
• gravel;
• crushed stone;
• sifter

River sand is good for a concrete foundation, but don’t be upset if you can’t get it anywhere. Sand and crushed stone can be different. Even quarry sand will do. The main thing is that it is clean and free of clay impurities. First of all, the sand needs to be sifted through a special sieve so that it becomes fine and without any kind of stones. Very often crushed stone is mixed with soil. Since the earth includes organic substances in its composition, it also should not get into ready-mixed concrete. Therefore, before use, the crushed stone must be rinsed thoroughly under a hose.

The concrete under the foundation will mainly consist of cement. There should be approximately three times less other additives in the solution. After the components are correctly distributed, the dry mixture is placed in a concrete mixer and rotated there several times. This is necessary so that the mixture becomes more homogeneous. And only after that you can add clean water. Water should make up about 20% of the total concrete solution, then it will have the correct average viscosity. If you pour too much water, the filler will rise to the top and the consistency of the solution will be disrupted. This class of mortar is not suitable; it will quickly begin to develop cracks. The strength of the foundation will be greatly reduced. You should be aware that you cannot use sea ​​water, it must be clean. Even factories use drinking water.

Read also: Auger for transporting cement

Quantity calculation

Scheme for calculating the amount of concrete for a strip foundation.

The finished solution quickly sets and cannot be reused. If too much solution is prepared, then you will simply have to throw away the excess. It turns out that your money will be thrown away along with it. To avoid such a nuisance, it is necessary to accurately calculate the required amount of mortar for the foundation. First you need to find out what kind of shrinkage the brand you are using has. The greater the shrinkage, the more concrete will be needed. For the foundation of a parallelepiped-shaped house, calculating the required amount of mortar is not so difficult. There is even a special calculation formula. First, the length is multiplied by the width and height, and then the resulting figure is multiplied by the shrinkage coefficient. We divide what we get by 1.05 (this is the volume that will be occupied additional elements, for example, fittings). To calculate a foundation of a different shape, you will have to remember the geometry.

http://youtu.be/LcUf9TT4QNg

There is another interesting fact: when mixing different grades of concrete for the foundation, you can get the required solution of a completely different class. The finished solution must be used in two hours before it hardens. That's all you need to know about concrete foundations in order for the construction to be successful.

Page 2

• Reinforcement
• Manufacturing
• Tools
• Installation
• Calculation
• Repair

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Brands of concrete: how to choose the right brand of concrete

Anyone, even those far from construction, knows that the construction concept of concrete, and the adjective concrete, is associated with something very durable.

This is not surprising; perhaps there is no construction work in which concrete is not used. The foundations of houses are poured from concrete, and monolithic frames of buildings are made. Concrete is used to construct floor subfloors, floors are poured in garages and in factories, and subfloors are made from concrete in rooms. Concrete pools are poured from special grades of concrete and runways are built at airports. Concrete is the main material for the production of construction and road slabs, foundation blocks. In general, concrete is everywhere in construction. So what is concrete?

What is concrete

Concrete is a mixture of four constituent materials: cement, sand, crushed stone and water. The components of concrete are mixed in special proportions, forming a thick construction mixture, which, after hardening, forms a durable, monolithic product. Due to its fluidity when mixed, concrete can be given any shape using the so-called formwork.

The proportions of cement, sand, crushed stone, water in the concrete solution are strictly calculated, but are not constant values. Depending on the proportions of its components, concrete is divided into concrete grades. The main difference in concrete grades is the strength of the resulting concrete product and, as a result, the different areas of its application.

Concrete grades and cement grades

Often, the grades of concrete are confused with the grade of cement used. This is partly true, but not entirely correct. Let me give you an example, on M300 concrete. For M300 concrete, the following proportions of components are possible:

• cement M400 - 1 kg, 1.9 kg of sand, 3.7 kg of crushed stone.
• Or cement M500 - 1 kg, 2.4 sand, 4.3 crushed stone.

As you can see, different brands of cement are used for one brand of concrete.

Concrete grades and concrete class

There is such a thing as ready-mixed concrete. Ready-mixed concrete is concrete manufactured in a factory and ready for delivery to the site by special machines. The second name for ready-mixed concrete is BSG - ready-mix concrete.

According to the standards, ready-mixed concrete is designated by the grade of concrete and the class of concrete. For example, concrete grade M300, class B22.5. The grade of concrete indicates the technology of its production, and the class of concrete shows it quality characteristics. Typically, the class of concrete is tied to its grade and concrete is designated by the grade of concrete with an additional indication in parentheses of the concrete class. For example, concrete grade M150 and concrete class B12.5 are the same product, which is labeled as ready-mixed concrete M150 (B12.5).

Let's see how concrete differs between different brands.

Ready-mixed concrete grades

In listing the grades of concrete, we will go from “hard to soft”, that is, from hard grades of concrete to “softer” ones, it is correct to say lightweight concrete.

Concrete M550, class B45 is the most durable ready-mixed concrete. The proportions of cement in concrete grade M550 are maximum. Used in production processes in the manufacture of special reinforced concrete products and in the construction of hydraulic structures.

Concrete M500, class B40, similar to concrete M550. Its purpose is also for buildings and products that are constantly in contact with water. Concrete grades M500 and M550 are extremely expensive.

Concrete grades M400, class B35 and M450, class B30, also belong to high-strength concrete, and are used in civil construction of structures close to water (waterworks, metro), as well as premises for special-purpose reinforced concrete products and bank vaults.

Concrete grade M350, class B25. This concrete is used to construct the foundations of multi-story buildings. This concrete is the main one in the production of reinforced concrete products, monolithic construction, production of road slabs and hollow slabs. M350 concrete is indispensable for pouring concrete pools, load-bearing columns, and runways. In private construction, the use of M350 concrete is not rational.

Concrete grade M300, class B22.5. Popular ready-mixed concrete for the construction of strip, pile and other monolithic foundations, popular in private construction.

Concretes M200, class B15 and M250, class B20 are similar concretes in characteristics and applications. Foundations are made from such concrete low-rise buildings, small stairs. This concrete is used to construct paths and blind areas around the house. It is quite reasonable to use concrete M200 or M250 for flooring in the garage.

Concrete grade M150, class B12.5, is called lightweight concrete. Concrete of this brand is most common in private construction and rough finishing of premises. It is used to install subfloors in the house, fill walking paths, and level floors with screeds.

Concrete grade M100, class B7.5. Lightweight concrete used in preparatory work before reinforcement and in the construction of foundations.

Concrete grades M50 and M75. More often called cement mortars. Used in laying bricks and wall blocks, plastering works. It is distinguished by the absence of crushed stone and a large amount of cement and sand in the composition. In the everyday life of builders, such a solution is rarely called concrete. More correct name cement mortar or sand mixture.

About concrete hardening

When working with all types of concrete, we remember the following:

The technological strength of concrete is achieved within 28-30 days from the moment it is poured;

Strength of 60% is achieved after 7-8 days;

Durability sufficient for walking comes after three days.

The maximum strength of high grade concrete is achieved after 6 months. That is why it is better to build private houses a season after pouring the foundation.

It is important to ensure uniform, natural drying of the concrete, and at elevated temperatures it is necessary to pour (wet) the drying concrete for a week and cover the concrete with polyethylene for the entire time it gains strength.

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High-tech concretes in Russia

We (Volodin and Abramov) Hack the recipes of any foreign concrete technologies. > > > > > Technology No. 01 Self-compacting concrete

(consistency of honey)

We can produce real self-compacting concrete SF3 according to EN 206-1 (and not the garbage that is made and passed off in Russia as self-compacting concrete).

01. Glossy concrete

02. Pouring densely reinforced structures

03. Injection (injection through a tube)

04. Construction of high-rise buildings (from 40 floors)

The development time for such concrete is 1 week.

Here's our video of (real!) self-compacting concrete:

> > > > > Technology No. 02 Perpetual cement slurries (for the oil industry) “heroin” for the oil industry Do you extract oil? A lot of oil? Did you know that the markup on dry tampon mixture is from 400% (almost like heroin)? Moreover, most mixtures have the strength of home plaster. This is one of the most conservative areas of concrete science. Oil workers are not experts in concrete. This is used by enterprising guys all over the world.

Do you want us to “hack” the formulation of Western cement mortars? (from you only samples of these mixtures)

Development time (or “hacking” of Western technology): up to 6 months

Why are we the best in concrete technology?

Volodin Vladimir Mikhailovich (technical director)

01. Brought the grade of concrete to the incredible M2500

(having obtained the strongest mass-produced concrete in Europe)

02. Participated in exposing concrete in the Moscow City high-rises

03. Developed high-strength concrete for the Vostochny Cosmodrome

04. Wrote a dissertation on high-strength concrete

06. Winner of international competitions in concrete science (list)

08. Inventor (patent holder)

Abramov Dmitry Alexandrovich (director)

01. Introduced the technology at more than ten large factories in the CIS

02. Found a site with a raw material base for the production of the cheapest high-strength concrete (in Europe)

03. Inventor

Why is it easy with us?

01. We get results in ANY region

02. We DO NOT sell anything

03. You DO NOT have to buy equipment

04. Concrete only from your LOCAL components

05. Someone will do better? We will pay you ourselves!

Need more information?

Come for a visit! We are located at a HUGE concrete plant Address: Russia, Togliatti, Nikonova 52 International. Airport: KUF (Kurumoch) (40 min drive to us) Railway station: Zhigulevskoe Sea (6 min drive to us)