At what temperature can be filled with concrete

On the temperature of hardening depends directly on the strength of concrete. If during the construction of the weather conditions did not meet the required parameters, the process of formation of the concrete structure will be delayed or, worse still, there will be defects in the concrete mass. At what temperature can be poured concreteAnd when to stop working? Is it possible to accelerate the solidification of concrete?

What you should know about concrete

Concrete It consists of only a few components:

• filler;
• water;
• binder;
• special additives.

Itself binder, cement, When contacted with water it turns into a very solid mass. Although this embodiment has high strength composition, however, without reinforcement, So just cement stone will crack from the load.

Moreover, use of these excipients significantly reduces the cost of the mixture.

Note! Regulations require pouring the foundation to use for the manufacture of concrete construction rubble with strength greater than the strength of concrete. Full curing of the concrete takes place only six months after potting. During this period schebonka prevents the deformation structure.

The ratio of marks and concrete filler:

Filler	Strength, units	grade of concrete	application
Limestone	500	M 200	This mixture is used to fill the floor, screed, Arrangement cobbled tracks
Gravel	1000	M 300	It applied in individual housing construction to fill foundation. It has low radioactivity.
Granite	1400	M450	Suitable for the manufacture of high-strength structures - columns, poolsBridges.

Filler binds cement in admixture with water. concrete quality depends on the brand of cement. for the erection foundation Private home enough cement brand M300, and subject to the following proportions:

• water 01.10;
• sand 6/10;
• Cement 3/10;
• filling 4/10.

Which notation you need to pay attention to when buying a cement:

• In (3.5 to 60) - a class of concrete strength;
• F - frost, shows cycles of freezing and thawing, which can withstand the design. For Russia the latitude index should be at least 200.
• Wo - water permeability. It has a range of 2 to 20. The higher the index - the more resistant to the effects obtained by the construction dirt and atmospheric moisture. Hydraulic resistance of 20 units indicates the possibility of the use of concrete for the construction of swimming pools.
• P - mobility index. Typically, less than 5 units. A4 - suitable for everything foundation private house.

Related article:

How to choose the right concrete blocks.The review will consider the characteristics, properties, advantages, the secrets of proper selection and the average cost of building materials, as well as practical recommendations for its implementation.

Cooking fill

Before you cook and pour the solution, you need to carefully calculate volume the required mixture. It is especially important to make educated calculations, if you plan to order a ready-mixed concrete.

If the mixture is not enough, it's too bad. The design does not pick up the necessary strength, which subsequently lead to the deformation of the walls or their collapse.

How to make a calculation

From the brand of cement and concrete composition of the mixture ratio of shrinkage depends. The higher shrinkage, the greater the need of solution.

Note! Concrete with a filler of fine fraction is used primarily to fill voids. Krupnofraktsionny filler is used for arranging monolithic structures.

Normal rectangular foundation structure of the tape is calculated as follows: length x width x height shrinkage ratio. The resulting value is divided by 1.05 (as occupied reinforcements).

It is more difficult to calculate the amount of complex shape grounds. Useful high-school geometry. The principle is the same calculation, using the coefficient of shrinkage and dividing by 1.05.

Concrete M200 (strength class B15)

Concrete M300 (V22.5 strength class)

How to prepare a solution

For foundation Private house can prepare a solution on their own, without resorting to the services of companies that produce concrete for sale.

Algorithm solution preparation:

• Calculation volume of the mixture and respective quantities of the components. The classical ratio of ingredients: 1 cement / sand 3/5 schebonki.
• Preparing the container for mixing. From its volume will depend on the number of batches. Conveniently, when there is a portable concrete mixer on hand electric motor. It saves time and energy. The resulting solution is qualitatively prepared manually.

• All the dry parts prior to the addition of water are thoroughly mixed. After water is gradually added in the necessary quantity.
• The resulting mixture should be repeatedly stir until smooth consistency desired thickness.

Important! All the tools for mixing must be clean. In this case, the mixture will get nothing superfluous, and the composition will not adhere to the shovel or mixer wall.

At what temperature it can be filled with concrete, and whether to stop the work in the winter?

Probability of filling the basement in the winter the majority of developers will cause doubt and they are justified. Everyone knows that water is one of the main components of concrete, has the ability to freeze at low temperatures.

Modern construction technology allowed to avoid such an outcome. Now you can get high-quality concrete and use it at a temperature of up to minus fifteen degrees. Different methods are used for the rapid construction of which stand to talk more.

Related article:

Table of thermal conductivity of building materials.From high-quality selection of necessary materials directly dependent thermal resistance of your home, because the mistake, in the initial calculations, you do run the risk of defective insulation of the building. To help you, given a detailed table of the thermal conductivity of building materials, as described in this article.

Using a heat gun for pouring concrete at low temperatures

Most of the strength of the concrete mix is ​​gaining in the first 48 hours. At this time, it is important to protect especially the solution from freezing. You can set the foundation for building perimeter heat gun and heat the air before solidification of the mixture.

Warming by electricity

Pouring the foundation without warming up is not possible in winter. It can provide electric current, summed directly to the reinforcing metal grid. Thus there is a heating of the concrete in its thickness, which is more efficient than heating the entire construction site.

The use of special additives

to fill foundation spring, autumn or winter possible to use special additives, which act on the water in the concrete, preventing it from turning into ice crystals. Concrete mixture with such additives is called "cold".

At what temperature can be poured foundation autumn and whether to do it at all?

Why does the need arises - to pour the foundation for the house in the winter? Is it possible to start construction in autumn and why should organize themselves such difficulties?

There are several good reasons that push developers on such a risk:

• fragile soil on the site does not allow to produce high-quality pit to fill the earth continually showered. The frostbitten state all becomes much easier;
• construction is carried out in the northern region, where it is difficult to wait for the right temperature and thaw periods are so short that it is impossible to keep within the required timeframe;
• cheaper construction. Beginning in the fall and spring to mid-price of building materials and builders services fall;
• Seasonal worker builder schedule. Some professions employment is seasonal in nature, and it is from autumn to spring, some people have free time to engage in the construction site.

But every coin has two sides. And good reasons may result in unpleasant consequences:

• instead of saving winter filling of the foundation may result in additional expenses. The task to dig a pit in the frozen earth impossible without special equipment, as well as the procedure of mixing the cold;
• concrete discount in the winter may not contain the necessary additives. Buying a ready-made solution should ensure that it is "winter" capacity;
• labor workers during the cold season must be paid additionally due to the harsh weather conditions.

Everyone decides for himself, it is impossible or the foundation can be poured in the fall. At what temperature will be successful? Professionals say that and minus fifteen is possible to produce high-grade concrete construction. If you are working on their own, do not expect these frosts. More or less safe option - to minus five degrees, that is, the first frost of late autumn.

Winter additive into the concrete mix

The advantages of using antifreeze additives are obvious:

• their use will cost much cheaper procedures artificial warming of the soil using a heat gun;
• the use of additives is safe for humans, while the use of a current to heat the reinforcement cage without special skills fatal;
• Winter additives increase the strength of the concrete structure and its durability;
• solutions increase the plasticity of the concrete mix;
• additives to reduce the risk of deformation of shrinkage of the foundation;
• solutions were added to the concrete, the metal frame from the stored corrosion.

Important! Antifreeze additives can not be used at filling of the foundation below minus twenty degrees. "Winter" concrete is poured into the rain. Some types of fillers are incompatible with these solutions.

Winter kinds of additives:

1. Antifreeze. It reduces the temperature threshold of crystallization water in the solution. It does not change the speed setting of the mixture.
2. Sulfates. Increase the rate of hardening of the mixture. As a result of contact with water releases heat.
3. Silicates. Promote the formation of double salts, reducing crystallization temperature water.

Important! Please be aware that the concrete with the addition of sub-zero temperatures is gaining strength only thirty percent, seventy others will be recruited during the thaw. For this reason, bathed in the cool time of the year the foundation can not be subjected to significant loads.

Additive	properties
Potash	Solution accelerates the setting process. Adversely affects the strength of the structure, requires the addition of sodium tetraborate. A hazardous substance under the special security measures required with it.
borax	It is a mixture of ammonium, sodium salts, calcium salts and acids. Used to prevent the negative impact of calcium carbonate on the strength characteristics of concrete.
sodium nitrite	It is a poison, only transported in a special container. It reduces the temperature of the crystallization liquid. Prohibited use with brown due to the formation of toxic gases.
sodium formate	It is used as a plasticizer of concrete. It accelerates curing of the mixture.

Note! As winter additives are also used ammonia water, urea, alcohol solution of sodium formate.

How to care for winter foundation

• when forming formwork use insulation - foam or mineral wool. Such protection will keep the temperature of the mixture from an external ground impact.

• In the process of formation of the foundation you need to protect it from mechanical impact, monitor the integrity of the formwork.
• If formed small cracks, but the solution is not frozen, they can be eliminated by vibration.

When it is impossible, but very necessary

Before you decide at what temperature can be poured concrete, it is necessary to answer the main question: Are you willing to risk? Are the circumstances that make you contrive winter construction, so irresistible? If there is no escape - is necessary to qualitatively warm pit foam, to prepare concrete with the addition of antifreeze additives, for greater certainty, few days warm air over the structure using heat guns. In any case, bathed in frost foundations does not need to rush to build. It is necessary to wait for the establishment of warm weather.