Concrete is one of the most common building materials, which is used everywhere - thanks to its excellent strength and reliability.
The process of its creation is associated with the procedure for mixing the solution, which, as it solidifies, forms the final solid, monolithic structure.
Mixing of the mortar can not be done without the use of water, which serves to impart mass to the viscosity and takes an active part in the formation of the concrete block.
The process of hydration of binder and hard concrete under normal conditions proceeds quickly enough and the quality of the final product, usually, depends on little.
However, in low-temperature conditions( starting from -3 degrees Celsius and below), the key process slows down due to the fact that the water starts to freeze.
If the solution is placed back in comfortable temperature conditions, the process will resume, but serious quality losses are possible due to the fact that during the freezing process the water expands and, after thawing, the concrete is much more fragile due to the abundance of micro-waste.
The usual practice for construction is to create optimal conditions for solidification of concrete by maintaining a comfortable, warm temperature, but it is not always possible to create them.
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In such cases, antifreeze additives are used in concrete, which almost completely level out the problems that arise during the hardening of concrete in low temperature conditions.
Also they have one more useful property.
For the most part, antifreeze additives increase the frost resistance of the final unit, thereby improving its performance and extending its useful life.
How and what are they used for?
As already mentioned above - concrete does not harden at low temperatures, and if it does, the quality of the resulting material can hardly be called high.
In cases where construction can not be postponed until the time of increasing the average daily temperature, it is advisable to use antifreeze additives in concrete.
In some plants, around the place of pouring concrete, a closed box is built, the air in which is heated to a positive temperature and maintained until the concrete solidifies completely.
But this method is not always applicable.
The first thing you need to understand is that the area of the structures is different, so when building a small bath it will be appropriate, but it will be difficult to cover the foundation of a residential house.
Plus, to solve the problem with heating the air - it can often be very difficult. Of course, it is possible to use thermal guns for this, but all this is expensive and time-consuming and financially.
It was to eliminate all these complexities and invented antifreeze additives for concrete.
Their principle of operation is simple and complex at the same time. In fact, they react with water, significantly lowering the temperature of its freezing.
At the same time, they do not violate its structure and do not change the properties, so that their use does not affect the final quality of the product.
The approximate consumption of antifreeze additives in concrete is calculated depending on the ambient temperature. Additives are mixed with water, which is eventually used to create a concrete mix.
If the air temperature is above -10, the concentration of the additive should be around 5%( 1/20), at a temperature of -10 to -20, use a 10% solution( 1/10).
Further all develops on the same progression - for every 10 degrees of the thermometer the solution becomes more concentrated by 5%.There is also a small limitation in this system.
Antifreeze additives are not recommended for use at temperatures below -50 degrees.
This is due to the fact that the solution turns out to be too concentrated, which can lead to a shortage of water for the normal formation and solidification of concrete solution.
If we consider the composition of antifreeze additives in concrete, it is easy to see that depending on the manufacturer - it can vary.
Nothing surprising and frightening in this.
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Antifreeze additives include substances such as:
- potash( potassium carbonate);
- calcium chloride;
- sodium chloride;
- sodium nitrite and mixtures thereof.
Also, various organic salts are often added as antifreeze additives.
The difference in composition is due not only to the manufacturer's preferences, but also to the properties that each of the elements possesses.
It should also be noted that the use of only one of these elements leads to the inability to produce concrete with a combination of properties( viscous mobility, strength, waterproofness).
Because of this - most of the antifreeze additives are mixtures of different elements.
As for any other building material, there is a guest of anti-frost additives in concrete.
Compliance with the rules regulated in it is mandatory for both the manufacturer and the end user( builder).
GOST 22266-94, this is the number of this code of vowel rules and requirements for antifreeze additives. It is strongly recommended to choose additives indicating compliance with this guest.
Using antifreeze additives in concrete corresponding to this guest, you can be sure of the quality of the final product.
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Usually, all additives of Russian production have a sign of conformity to the guest, but there is no such mark on foreign products.
The choice of mixtures of European production should be approached with caution, but it is better not to be at all in view of too much difference in operating conditions.
Prices
With the purchase of antifreeze additives, no problems arise.
It is usually possible to buy antifreeze additives in concrete in any construction shop, and in large shopping centers or specialized supermarkets there are usually a choice of a dozen different additives from different manufacturers.
Normally the price of a frost protection additive for concrete is rather low and fluctuates between 80-150 rubles per package( 5 liters).
Of course, depending on the manufacturer, the price may be different from the specified, however, construction materials, especially consumables, are the category of goods in which it is clearly not worth overpaying for packaging.
Antifreeze additives overseas production usually cost almost twice as much as domestic.
This is not connected with high quality, but with expenses related to transportation.
In general, it is advisable to give preference to Russian producers in not only for the sake of economy, but also due to better adaptability to climatic conditions.
