Is it possible to make a foundation for the house in winter. Is it possible to fill the foundation in winter? Pour the foundation in the winter - pros and cons
If the construction of the house is carried out with their own hands, it is not always possible to choose a favorable period for construction. Sometimes vacation falls for the winter, so you have to look for a way out of the situation. Is it realized in winter? Yes, but it will be more complicated than in the warm season. There are two solutions to the problem:
- Building. We are not waiting for the arrival of spring, and we take the situation in our hands. We select special solutions, a suitable look of the foundation and begin work.
- Conservation of the foundation for the winter. For example, you started construction work in November, but I don't really want to continue construction. Sometimes it is simply impracticable, so you need to leave work until spring.
We will analyze both options in detail, as the construction, and conservation are complex and time-consuming processes, so it is better to trust them to professional builders.
We are building in winter - the types of foundations
For winter construction there are two main types of foundations that can be used in the cold:
- Ribbon foundation. To facilitate the work, the masters are recommended to make a choice toward finished blocks. "Wet" operations better leave for a warm period.
- Pile foundation. The base where concrete piles are used as the main element will be an excellent solution for lightweight structures. Usually, the pile foundation is chosen for houses from a tree.
Cooking a concrete mix
Of course, it will not be possible to make a ribbon foundation in winter from ordinary concrete. It will take a solution containing special additives in its composition. These modifiers do not give concrete to frozen ahead of time, the mixture is seized only after the dialing of the required strength.
Also, the "winter" additives contribute to a simpler fill. The choice of the desired mixture should be engaged in a professional, as they differ in the speed of solidification and frost resistance. The packaging is usually indicated how many modifiers should have to concrete mixture.
Pile foundation in winter
This type of foundation can be erected into all seasons. Builders do not need to adapt under the weather, as it does not affect installation work. Construction passes as follows:
- Piles to the depth of freezing are screwed into the frozen soil. Typically, the distance is 1.5 meters.
- The next step is to cut down the level.
- Next, the concrete mixture floods the foundation.
- Now you can put the headings on piles.
- If necessary, waterproofing and thermal insulation are carried out.
- Piles contribute to a uniform distribution of the load throughout the foundation area.
Features of applying additives
Before starting work, you must familiarize yourself with the main features of modifiers. Water for solution is required by 10-15% less, if compared with the usual mixture. Modifiers perform their tasks to a certain threshold of frost - this is -25 degrees. You also need to monitor air humidity. If this indicator exceeded 60%, then the use of additives cannot be used.
We often repeat that you need to choose a solution and modifiers, because you need to know how additives will react with a certain type of concrete. Despite the fact that modifiers help to cope with the frost, it will not work out without thermal insulation. The base concrete should be warmed so that the design temperature does not change much. Now consider the pros and cons of work in the winter.
Positive and negative points
First, it is worth considering the advantages:
- The soil performs the operation of the formwork, since the frozen soil does not appear;
- Savings on building materials. Do not forget that with the arrival of cold stores, shops are trying to get rid of seasonal materials.
- In some regions, a favorable season for construction lasts no more than 2 months, so to leave work for almost a year is an incorrect decision. It will help here "Winter" pile or ribbon foundation.
As you can see, there are advantages. Now look at the minuses:
- Although building materials will cost cheaply, but earthworks will be expensive if you hire builders;
- Some hosts decide to leave construction to warm pores for the reason that it is simply impossible to work in -20;
- Use special equipment in the frost will be problematic as a result, more expensive.
Preservation of foundation
You can perform preservation in several stages:
- Waterproofing of a finished or unfinished base;
- Thermal insulation of the foundation;
- Distribution of groundwater.
To understand how to leave the foundation for the winter without damage, each item must be disassembled.
Distraction of groundwater
Before starting construction, specialists from the construction bureau study the site where the future structure will stand. Surveying the characteristics of the soil, it is possible to determine if it is possible to do without removal of water or not. The soil saturated with moisture will not be able to ensure the strength for the house. Due to high humidity in concrete, cracks will appear, but the strongest blows for the construction will be winter - the liquid will fall into the pores of concrete and freeze.
The removal is performed using stocks and grooves. By doing this action, you protect the foundation and the future house from the adverse effects of moisture. The scheme is as follows:
- At your site, experts find the lowest place.
- Next, the pit is broken, which will continue to serve as a reservoir.
- All over the perimeter of the base, the grooves must be pulled out with a depth of about 40 centimeters. The exception will be grooves from the pit - there is a depth to increase to 50 cm.
- Stocks should be crushed perpendicular to the groove, the direction should be towards the tanks.
Waterproofing and thermal insulation
4 weeks after the fill of the solution, you can begin to make waterproofing. It is worth saying that such protection is not needed in all cases. In any case, this issue is solved when planning a foundation.
Have time to make waterproofing needed before the onset of cold weather, it concerns tape and tile structures. If you chose a columnar or pile foundation, the waterproofing will not need.
As for insulation, it is performed throughout the perimeter of the base. As a material, you can choose extruded polystyrene foam. It is convenient to work with it, as the material is sold by plates. Of course, thermal insulation is carried out after waterproofing. After the plates are laid, you can sprinkle chips or straw throughout the perimeter of the base. Further, the foundation needs to be covered with a film and make a heavy material. After that, the design can be calm for the winter.
Outcome: Is it possible to pour?
As you can see, there are many "for" and "against" the fill of the foundation in the winter period, but the fact remains a fact - when it is necessary, the foundation is poured even in frosts. Yes, the work is specific, you need to understand the additives so that a high-quality solution is obtained at the exit. If you are not afraid of the cold, then boldly try to work.
Is it possible to fill the foundation in winter? Updated: February 26, 2018 by the author: zoomfund
Not so long ago, with the onset of frosting "freeze" in our latitudes, construction was accepted. And so no one else took it to start. Speech could not be about the construction of concrete foundations and reinforced analogues, if the thermometer was notified of the decrease in the marks below + 5º in daytime, and the negative temperature stated in the night. However, the duration of winter interruptions in construction forced the inhabitants of the Northern country to seek methods that allow concrete work in the cold. So there were ways, thanks to which a solid monolithic base can be built at low temperatures. Finding out how to fill the foundation in a difficult frost period, you can easily begin the construction of the bath in the winter.
Nuances of concreting in winter
The winter was considered not the best period, both for filling the monolithic design, and for the construction of supporting elements of burbill and pile types of foundation. The reason for the crystallization of water is one of the main components of the concrete solution. Turning into ice, water not only prevents the normal flow of the process of hydration of concrete mix - that is, the formation of reliable molecular bonds at the expense of its work. Due to the formation of ice crystals, the dimensions of which increase the source volume of water by 10%, porosity increases. This fact is in no way contributes to obtaining the planned strength of the foundation, but reduces substantially.
We will understand in the hydration mechanism
Concreting is the process of gradual transition of cement mixture with sand and rubble from the liquid phase in the fictional state in the rank. At a temperature of + 15º and with a favorable moisture-favorable level, the following occurs:
- first, a peculiar shell of sodium hydraulicate is formed on the surface of the flooded structure;
- then the upper layers of the flooded mass are connected to the reaction - the solid cement grains are gradually sucking with moisture, due to which the components of the solution are glued together;
- next, the outer shell, losing evaporating water, begins to be tightened;
- then the reaction takes a deeper layers;
- and then, in the same sequence, while 28 days later, the concrete structure does not get maximum strength.
If the foundation falls into a hot dry day, the hydration rate is increasing. But the water begins to evaporate active, leaving instead of the pores unfilled with the bound concrete. At low temperatures, the reaction is slowed down, but the pores appear already due to the formation of ice crystals. In order to avoid what the fill of the foundation in the winter is made according to special rules, which makes it possible to obtain the temperature of the solution required for normal hardening inside the compound concrete array or individual columns.
Hydration is accompanied by spontaneous increase in temperature. The greater the thickness and size of the concrete structure, the more concrete allocates heat and cools slower. Therefore, it is not necessary to carry the fill of the support pillars in the frost, it is desirable to prefer the tape or monolith. If around massive structures arrange a heat-saving formwork from insulating mats or plates, with minor decreases of temperature you can do without additional triggers.
Classification and analysis of the methods of concreting
The hosts, puzzled by the problem, is it possible to flood the foundation in the winter, they receive an unambiguous affirmative answer, but with many variations. Options for solving the problem of preserving or forming the conditions necessary for normal hydration depend:
- from design dimensions;
- from the chemical composition of the concrete mix and from the proportions of the components;
- from the brand of binder cement and the subtleties of its grinding;
- from climatic nuances;
- from the opportunity to heat water and aggregate.
Often the heat released during hydration is not enough to create the conditions necessary for the contee in the frost period. A slight grinding of cement helps slightly, at the expense of which it enters the reaction faster and releases more heat when connecting to water. It also contributes to heating water and aggregate before the kneading.
Attention. You can warm up only water and aggregates. Cement is impossible to warm, otherwise it will lose the binding properties.
Usually in our latitudes for the winter fill, the solution is not used with a temperature above 21º C, given that when moving from concrete mixer, it will give an atmosphere of 4.5-5º C. To obtain the working temperature of concrete, it is enough to heat up to 32º. At temperatures above the specified value, hot water is first mixed with fillers, then the cement is entered into portion.
Save the temperature of the solution will help an increase in the kneading period. Carefully mixed concrete will rapidly take it positioning positions in the formwork, it will cool down the path. Therefore, builders recommend increasing the mixing time of the components of the concrete mix by 25% to optimize the fluidity and apply finely ground cement.
The simplest warming of concrete mix
An option with a separate heating of water, aggregate or completely mixture in a concrete mixer by means of a roar, heat gun, a gas burner is suitable for those who are puzzled by the question of how to flood the foundation in winter with light night freezes and the positive testimony of the thermometer during the day.
This scheme has strict rules:
- heating water MAX to 80º C;
- the initial waters of water with the aggregate and the subsequent gradual introduction of cement, preferably from m from 400 to 500;
- the use of additives that increase the speed of hardening.
Council. The use of the vibration device is optional for private buildings, but desirable. The construction vibrator is needed for the sealing of the concrete mixture, to reduce the air content, reducing porosity.
After the fill, the concrete array is immediately covered with tarpauloset, bags, insulating mats, styloil blankets or straw. Until the configuration of strength, the temperature needs to be maintained by setting around the roar foundation or other heat generating devices. Then heating stop and dismantle the formwork. If you could not fully open the concrete, it can be possible to freeze. All processes will be conserved, and after the defrosting, the reaction will go to their note minus the period between freezing and reverse action.
Attention. Tubing is performed only after a sufficient durability. According to the regulations of the SNIPA III-15-76, the design should score 70% regardless of the brand of concrete without additives.
Typically, the foundations built according to the rules are not lost in the strength properties of more than 5% of the design value if the water-cement ratio of the mixture was no more than 0.6.
Concrete kneading in the frost period is complex. The justified solution of the rational owner will appeal to the services of builders or buying a ready-made solution with modifying additives at the factory. There and the proportions will calculate, and weather conditions will take into account. With the finished solution, the solution to the question "How in the winter it is properly filling the foundation with your own hands" will cease to be an insoluble task.
Using concrete with modifying additives
The introduction into the composition of antiorrosal additives is also directed to an increase in thermal energy produced by concrete independently. In addition to this stimulating action, modifiers underestimate the "threshold" of water crystallization. Due to which concrete hydration will pass along the usual scheme at a lower than for standard temperatures.
In order to form antimorable properties, concrete is enriched in the main calcium chloride. It is possible to introduce into the solution by no more than 2% of the total mass, otherwise the strength of the concrete structure on compression will significantly reduce. With stable degree readings below zero, the solution is mixed with sodium chloride (ordinary salt), sweat, sodium nitrate, providing trouble-free concreting in - 15º frost. Despite the availability of additives, masters, looking for methods, as in cold weather, fill the foundation under the bath, do not experiment with the formulas of the solution. It is better to purchase a ready-made composition without the risk of irrevocable loss of all invested money.
When applying antiorrosal modifiers to dismantling formwork, you can start when:
- m200 solution will drop 40% strength;
- concrete with m to 300 picks 30%;
- concrete with marking M400 and higher picks 20%.
Most often, the use of concrete with modifiers is combined with artificial heating methods. When combining an improved concrete, for example, with an electric heating, it is necessary to ensure that the urea will be detected at + 40º C, and due to 30% preheated to 30º, the strength will be attended by 30%.
Technically complex ways of winter concreting
Briefly consider the methods of artificial heating of concrete in the formwork, the purpose of which is to increase the rates of setting the mixture. Depending on the possibility of using the electrical appliances, the presence of insulating materials and the financial framework of the construction owner of a country estate can choose, more precisely, to order in a construction organization:
- thermosa method concreting. The leakage of thermal energy and the cooling of the body of the concrete array eliminates the insulating casing, built around the formwork. It is a metal case with an electric, steam or water circuit, heating hard concrete;
- fill the foundation with steam-heating. To implement concreting with heating, steam solution will require powerful equipment, considerable amount of water. You need to accurately calculate the number of pipes installed in the formwork, and to build the supplyable pipeline, which will forever remain in the body of the structure. Due to the considerable cost and complexity of implementation, it is rare some of the private traders prefer paroprogerev.
- warry device around the flooded foundation Also not the cheapest way, because you need to build a large tarpaulin or polyethylene tent. Inside the tent it is necessary to maintain a constant temperature, follow the moisture, so as not to overcover the concrete. Heat heat with portable stoves, cannons, electrical equipment. For the construction of the warmth, a separate project is created, it is dismantled after removal of formwork.
- concreting with electrical heatingcarried out by the start of the current on the wires in the fresh concrete with steel residential. Wire with a calculated step "entangled" formwork or reinforcement design, or the heating cable is simply fit into the concrete. Against the background of the above options, this is the most economical and easy-to-implement method, therefore the most common.
- infrared and induction options for electric heating, arranged by analogy of tubular shades, carborund rod emitters or cable creating magnetic fields in fittings or in steel formwork.
All listed methods do not belong to the discharge of work, for the execution of which it is worth being taken without knowledge and qualifications. We need calculations of the value of the supplied energy, the design of additional devices, and the advantages of the good electricity also the skills.
General rules that need to adhere
Let's start with the fact that everyone can find out if it is possible to fill the foundation of parts in winter conditions, will surely disappoint the answer. Solid "no". And until the end of the fill work around the clock. Styling should be made small in height and length segments, immediately overlapping them with the following layer to avoid temperature loss. If for any unforeseen reasons on the surface of the filled concrete, a helium shell began to form, it must be made.
It is important to competently prepare an object to the fill:
- clear the pit or trench from snow, leaf and remove Failed from the bottom and from the reinforcement. To prevent the freezing and icing of the bottom, you need to hide the trench or straw straw immediately after digging and laying a sand pillow;
- heat the bottom between the formwork walls is approximately 30 cm. You can not pour concrete on top of the freezed soil! Having thawing under the mass of the solution, the soil will settle. It is not a fact that the sediment will be uniform. Especially there is no confidence that the foundation will not see too much;
- ensure a formwork approach from all sides.
The rules of safe effectively fill concrete in winter a little, but compliance should be strict. It is much easier to show zeal before the fill and in the process of work, than to spend time and money for dismantling and alterations.
Any construction is better to produce dry warm weather. But a private house, if he is erected with his own hands, is built in his free time. One warm season on it, as a rule, is not enough. In order not to stretch the process for many years, some of its stages are carried out in winter.
Scarlet (or foundation) can be teams from blocks or plates. In this case (as well as under construction), the peculiarity is that the fixation of individual elements is performed by cement-sandy solution. They are mainly applicable to the same rules as to concrete.
Filling the foundation in winter with minus 5
The measures necessary for the device of high-quality base in winter:
- use of modifiers;
- heated solution;
- thermal insulation of the finished foundation.
The problem component of concrete is water. Even if in the process of fill it is liquid, the full dehydration is impossible. Those. The solution is not captured by evaporation of water, and freezes. This problem is solved by adding special modifiers to a mixture that slow down the hardening, which allows the concrete to dial strength.
The modifying agent is selected in accordance with the rates of frost resistance. The desired number is indicated in the instructions, there is a scale on the package: the rate depending on temperature. The minimum permissible air temperature is -25 degrees.
note
When preparing a solution with a modifier, the amount of water is reduced by 10-15%. With high humidity (60% and more) supplements cannot be used.
You should also explore the instructions for the interaction of the ingredient with the metal.
For breeding mixture in winter, heated water is used. The flooded foundation must be warmed, especially the first couple of days. To warm up, you can use a heat gun (the power is selected depending on the size of the foundation). Another option is a heating cable or reinforcing bars with a 380 volt electrotox connected.
Concrete gains strength for a month. After that, you need to produce vertical and, as well as insulate the finished base. If there is a long time before the arrival, the foundation can be preserved: it is covered with waterproofing film and thermal insulation material:
- polystyrene foam (foam);
- sand;
- ceramzit;
- sawdust;
- priming.
All insulation in one way or another are hygroscopic, they need to close with dense polyethylene on top.
The easiest option is to fall asleep the base of snow. In this case, the film must be raised under the snow, otherwise the concrete will absorb water during thaw.
In accordance with current building standards enshrined by the relevant gtales and lightning, concrete foundation gains strength for 28 days. Only after the specified time, you can begin the construction of the planned building on top of the flooded base. The situation in respect of the 28-day period is relevant for the warm season, because In winter, concrete gains strength much slower or, if you do not take care of performing some technological requirements, does not gain it at all.
Note! In the construction of supporting structures in winter, it is customary to count the period of the year, with the arrival of which the daily air temperature ceases to rise above + 15 ° C, and the night drops below 0 ° C.
Hence the question: Does it be sure to wait for warming to pour the foundation? It is desirable, but not necessarily. If it was possible to work with concrete only in warm weather, in the districts of permafrost, in the territory of which summer in its traditional understanding does not happen in general, it would not be better for any modern buildings.
The technologies of arrangement of various types of reference grounds were considered in detail in the relevant publications of the site, to describe them again does not make sense. You are also invited to find out what conditions should be respected to the successful fill of the foundation during the cold season and with what difficulties can be faced with the recommendations of qualified specialists.
It is not necessary to talk about the benefits of winter fill the foundation. You can only feel some benefit from such an event if a third-party brigade will be engaged in the arrangement of the reference design. The meaning is: in winter orders few and workers reduce the price, attracting the attention of the Customer to the tempting proposals on the fill of the foundation in December-January, to continue construction by March-April.
It is possible to count on a favorable outcome of such a venture in the event that the customer hires a proven brigade with good reviews and appropriate qualifications. Otherwise, the imaginary savings will be wrapped only by even greater costs, because In case of violation of technology, concrete may not be captured and the foundation simply camshed with the arrival of heat.
The negative moments of the concomitant winter fill of the foundation are quite a lot.
Firstly, the complexity of excavation of earthworks increases - to prepare a trench / hammering in the conditions of frozen soil on its own forces is unlikely to succeed. The only option is to resort to the use of special excavator techniques, which will not be better reflected in the final cost of the work.
Secondly, the efficiency of work is significantly reduced. Everyone, who at least once had to do certain construction events in the cold season, perfectly knows how difficult it is to make the same work in winter than in warm weather.
Thirdly, the total costs increase. It is justified by the simplest fact that it is necessary to buy additional modifying additives that contribute to an increase in the index of the frost-resistant concrete and making the foundation possible as such. With superficial acquaintance with the market situation, the price of modifiers may seem relatively irrelevant. But it is important to understand that additives have to be used in large quantities, and the total costs for their purchase will be very significant.
Thus, if the construction site is located outside the regions of permafrost, and the deadlines for the completion of work are not "burning", carefully glue all the advantages and disadvantages of winter concreting, before you decide on the implementation of such an event.
Video - Benefits of Winter Construction
About frost-resistant additives
Concretes poorly tolerate the effect of negative temperature - in such conditions, the material is destroyed, because During the freezing, the process of natural conversion of water from a liquid into a solid, accompanied by an increase in volume and discharge of various internal efforts and stresses. To level the listed negative impacts, additives that increase the frost resistance of concrete are used. The frost resistance rate is determined mainly by the presence of pores in the composition of concrete. In these microscopic voids there may be ice, without creating, while hazardous pressure for the material.
The greatest efficiency is characterized by additives with the content of surfactants. For example, the use of plasticizing additives such as SDB has a positive effect on frost resistance rates, because When using such modifiers, the formation of the optimal structure of the material is noted.
Under the optimal in this case, it should be understood a dense, not a microporous structure. It is with a dense structure that there is a slowdown in the grasp of the cement test, which increases the likelihood of the maximum amount of cement to the reaction and, therefore, gives concrete a chance to a full-fledged durability.
If necessary, special gas-forming additives may be included in solutions. Their use leads to the formation of spherical micropores, also contributing to the increase in frost resistance.
Important! Count on the positive effect of additives and modifiers can be solely provided with strict compliance with the manufacturer's instructions. When adding an insufficient amount of modifier into solution, there will be no pronounced positive changes and the material will begin to freeze, due to cement stone it will not be able to form. With the arrival of heat, the cement hydration processes are restored, however the structure of the mixture will be strongly changed, which will not be better reflected in the final strength of the supporting structure.
The procedure for using each modifying additive is determined in accordance with the provisions of the manufacturer's instruction, but several general rules can be distinguished that retain their relevance when using any modifier. Information on such recommendations is provided in the table.
Table. Permissible conditions for using modifying additives
Conditions | Explanations |
---|---|
The amount of water in the composition of the concrete mix | Almost all existing modifying additives make it possible to reduce the amount of water added to the solution. On average, savings keep at the level of 10-15%. Depending on the type of modifier, this indicator may change - specify the instructions in an individual order. |
Air temperature at construction site | Certain temperature constraints are preserved even with the preparation of a concrete solution with the involvement of the corresponding modifiers - it is impossible to build a foundation if the air temperature on the street fell below -25 degrees (some additives allow you to increase this indicator to -35 degrees or more). |
Air humidity at the construction site | Modifying additives lose their effectiveness with an increase in air humidity above 60% mark. |
Important! When filling the foundation in winter, the list of necessary additional measures is not limited to the use of modifiers. Concrete It is necessary to warm up, heat insulating, protect against external influences and perform a number of other actions aimed at maintaining a certain temperature of the finished design - these moments will be individually discussed in the relevant section.
The list of existing modifying additives that increase the stability of concrete to negative temperatures is impressive. Next, you will be able to familiarize yourself with the brief description of the most popular and well-proven modifiers, but preliminarily examine several important comments regarding the correct use of additives.
Additive "Lignopan B-4" - an antiorious-plasticizing additive (up to -18 ° C), allows concreting at negative temperatures, reduce the water flow rate by 5-10% with equal-moving mixtures
First, remember: the summary costs for the purchase of modifying additives will be very significant. Be careful and initially buy those modifiers that are designed for applications in the conditions of your construction site.
Secondly, the rules for using different additives are different. Before applying the modifier, you must examine the manufacturer's instruction on the subject of the required amount of matter for a certain proportion of the solution.
The relative strength of concrete in different timing of hardening at different temperatures Concrete strength depending on his age at the time of freezing
The minimum strength of concrete at the time of its freezing
Recommended content of antiorrosal additives in concrete
The increase in concrete strength with antiorrosal additives
Table. Popular modifying additives
Name additive | Description |
---|---|
Accelerating Antiorrose Supplement UPD | The mixture containing waste production of the ingredients below in these equity ratios: Acetoxus ether - 7 fractions; Acetylacetone - 3 shares; Nitrochloractinide - 1 share. The finished solution has a dark brown color. The required amount of accelerating contamination additive varies in the range of 100-420 ml per cement added per kilogram and is specified separately according to the surrounding temperature. |
The substance is classified as a by-product of the production processes of the petrochemical industry. The shade of a transparent liquid can vary from soft straw to saturated brown. The additive is brought into a concrete solution along with the indent water. The required amount of the modifier varies within 2-6% (determined, again, almost, in accordance with the ambient temperature). |
|
Effective at temperatures up to -10 degrees. In case of use in warm weather, the modifier accelerates the grasp of concrete. | |
At the same time increases the frost resistance and the plasticity of concrete mixes. It has the form of a dark brown liquid solution. The modifier retains efficiency when used in temperature mode to -15 degrees. | |
It is used at a temperature similar to the elevated additive. Among the important advantages of the hydrosis should be noted the fact that, when contacting it, reinforcing rods, which are part of a concrete support structure, do not rust. | |
Additive, promoting the increase in frost resistance and plasticity of concrete. Effective when using up to -18 degrees. The required dosage varies within 2-4% and above, depending on the air temperature at the construction site. | |
Antifreeze, effectively manifest itself in concrete mixtures and solutions. The additive can be used at an air temperature of up to +5 degrees, which significantly reduces the freedom of action in the winter period, but it is necessary to add it in a relatively small quantity - only 0.2-0.8% of the cement weight. | |
It is an aqueous solution of ammonia gas. It is considered one of the most cost-effective modifying additives. It is characterized by a relatively low indicator of volume expansion, making the likelihood of a variety of deformation processes when filling the foundation in winter significantly decreases. |
Ammonium water more often than other additives is used in winter arrangement of supporting structures and deserves separate consideration.
Ammonia Water (Water Amiak) - Transportation
The concentration of the modifier, as before, is determined in accordance with the air temperature. Information on this account is given in the table.
As can be seen from the table, ammonia water retains efficiency even when used to prepare a concrete solution for filling the foundation at a temperature below -35 degrees. This property is a great advantage of ammonia water in front of other modifiers, the conditions of application of which are limited to an average -15-25-degree indicators.
The use of ammonia water, in contrast to many other modifiers, eliminates the risk of corrosion of the reinforcing frame. The additive does not have a negative impact on the quality of the adhesion of steel rods with concrete of the foundation, does not disrupt the frost resistance of the structure, does not form spots and heels on the surface of the designs of the structures.
When using ammonia water, a certain slowdown of the timing of concrete mixtures is noted - the composition will remain comfortable for laying for 4-7 hours.
Prices for anti-corrosion supplements for concrete
contamination additives for concrete
In order to understand the peculiarities of the fill of the concrete foundation at negative temperatures, it is necessary to study the processes flowing in solution in such conditions.
Concrete hardness is associated with hydration reaction. During its course, the interaction of cement and water minerals occurs, based on the results of which new connections arise. If concrete dehydration occurs prematurely, the process of hardening will slow down either even completely stop, as a result of which the foundation will not get the necessary strength, it will take place and cracks.
With negative temperatures, water without having time to join the reaction with cement components turns into ice. Without modifying additives and other concomitant protection, the hydration reaction will not be completed, therefore, concrete does not gain the desired hardness. As a result, a significant reduction in the strength of the supporting structure and its service life. The frozen water, along with this, increases in the amount, due to which there is a decrease in the coefficient of the concrete mixture with the reinforcing frame, which is also fraught with the destruction of the structure.
Considering the foregoing, the distrust of the majority of developers to the winter fill foundation becomes quite understandable. But if you consider the planned event with the mind and knowledge of the case, you can get a high-quality reference basis even at a negative air temperature. Moreover, in many cases it is the only possible solution.
Prices for cement-sand mix
cement-sand mixture
Methods for maintaining normal concrete temperature
There are several ways to ensure the right fill of high-quality, reliable and durable reference base during the cold season. You are invited to familiarize yourself with each of them and choose the most optimal option specifically for your case.
The use of modifying additives
Detailed information on modifiers that increase the frost resistance of concrete mixes was previously provided. Information regarding how the technological process was phased in the relevant publication. Next will be given only step-by-step recommendations regarding the normal flow of the process of hardening and set the strength of concrete fill in winter.
Before studying the preparation instructions for the preparation of a concrete mix for the fill of the foundation, remember the following important rules:
In terms of private construction, the introduction of a modifier into water is more convenient - no need to use dispensers, scales and other additional equipment used in industrial conditions during the preparation of dry mixtures. Yes, and to achieve homogeneity of the solution when the modifying additive is easier to enter the water - a building mixer or a drill with an appropriate nozzle will help.
The procedure for the preparation of a concrete solution using modifying additives is not much different from the sequence of preparation of the mixture for fill without use. Information on this is shown in the table.
Table. Cooking concrete manually using modifiers
Stage of work | Description |
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Ideally, you need to purchase or at least take temporary use (you can try to negotiate with the nearest construction company) Concrete mixer. In the absence of one, it will have to work manually, and this, even in the case of a small foundation (for example, with a 80-centimeter embedding support for a modest bathhouse with dimensions of 3x4 m, about 10 cubic meters of concrete), long and time consuming. If it is not possible to get a concrete mixer, use a wide container to knead the solution, for example, trough, as in the image. Additionally, you will need: hoe, shovel and bucket. |
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Dry components are mixed in the following proportions: to the share of cement (the material of the brand is not lower than M400) is added 3 shares of sainted sand (it is best to use a varinfraction sand, i.e. with sandbags of various sizes, not having clay and organic impurities, ideal The option is "enriched" mountain sand, in the absence of such - washed with river) and 5 shares of different sided chopenka without additional impurities. Components are thoroughly mixed with a hoe or another suitable device. | |
Traditionally, water is taken in the amount of 50% of the mass of cement. When using modifying additives, as noted, the required amount of water may decrease by 15-25% relative to the standard recipe - this moment, as well as the required proportion of the additive, is subject to individual clarification into the instructions for the selected modifier. The additive is entered into water, after which the components are mixed to a homogeneous state with the help of a construction mixer or an electrician with an appropriate nozzle. |
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The liquid component is brought into a dry mixture. Add water with a modifying additive and thoroughly mix the solution, trying to get rid of the lumps formed and provide absolute homogeneity. Properly cooked concrete solution for the fill of the foundation should slide from the shovel, without scattering, without spreading and does not settle. |
The sequence of the preparation of the solution in the concrete mixer is somewhat different from the above.
First, water is poured into the container, after which the desired amount of cement is added (according to the recipe). Next, the mixture is made in the mixture and the components are thoroughly mixed for 3-4 minutes. The concrete mixer turns off, a modifying additive is added to the container in the amount specified by the manufacturer, after which the crushed stone is made to the mixture (the proportions were indicated earlier), and the components are mixed for at least 10 minutes. At the output, a homogeneous mixture of normal density should be obtained.
Ready concrete is used for its intended purpose. References to the relevant instructions were previously brought. But one of the use of modifying additives, as noted, is not enough - it is necessary to take additional measures to ensure thermal insulation and, if necessary, the subsequent heating of the fill.
Important note! The use of antiorrotic modifying additives allows you to make a possible fill of the concrete foundation in the cold season, but it will still need to harden the hardening and a set of strength of the structure, rather than in warm weather.
A set of critical strength at negative temperatures occurs on average per month. Upon reaching critical strength, concrete begins to type design strength only after thawing. To achieve regulatory strength designs, 28 days will be required. Thus, the positive temperature of the protected reference base must be maintained and after the completion of concreting.
Fundament insulation
By solving the issue of organizing the thermal insulation of concrete fill, it is better to do at the stage of formworking. The technology consists in the construction of an indiscriminate structure from special polystyrene foam blocks instead of assembling a traditional formwork from wooden boards.
It looks like design as follows.
Photo of non-removable formwork
Failure formwork - these are elements of construction design (blocks or panels), which are connected to each other by the design principle
The market contains blocks of various sizes, which allows you to choose suitable elements for the formwork of the foundation of any shape and dimensions. The end parts of the blocks are equipped with grooves and gear cuts, which ensures the bonding elements without the need to use third-party fasteners.
An important advantage of this assembly method is the absence of cracks between the blocks, which guarantees the maximum possible quality of thermal insulation and eliminates the need for additional sealing of the joints.
Foundation Formwork - Elements
Polystyrene foam is not afraid of moisture, which allows you to abandon the device for solid waterproofing. In this case, the material is not subject to rotting, therefore, on the preservation of concrete fill, in contact with such a non-removable formwork, you can not worry.
The technology of arrangement of such insulation is reduced to the installation of non-removable formwork elements in the dummy pit / trench around the perimeter of the future reference site with their subsequent fastening by means of available grooves and gear cuts.
Helpful advice! To install in the corners of the trench, it is better to use specially intended angular blocks.
The use of such eliminates the likelihood of forming the formwork in the design of the formwork and deterioration of its thermal insulation characteristics.
Installing a non-removable formwork
Corner Collapsible module of non-removable formwork
Corner block of formwork
Embodiment assembly
Important! The carrying ability of the polystyrene foam formwork is limited - in case of its use, only a non-heavy wooden bath can be built on top of the finished foundation. The loads created by buildings from bricks and building blocks, with a large share of the probability lead to the destruction of polystyrene foam elements.
Additional aspects were considered in detail in the relevant publication.
To ensure the protection of a concrete base from snow and cold air masses, a canopy is constructed by tent type. As a protective material, a car awning or ordinary tarpaulin is well suited - they are characterized by high moisture-repellent properties and are strong enough to withstand the loads characteristic of the cold period of the year.
It will look like this design as follows.
In the photo, a full-fledged frame with vertical racks, horizontal crossbars and even improvised rafters for maintaining a tarp roof was built.
Specialists recommend not to regret the time and build just such a reliable framework. Moreover, when the foundation is arranged for a private bath, it does not take a lot of time and effort. Yes, and internal vertical supports in your case with a large share of probability will not be needed - the need for their application occurs only when arrangement of large-scale supporting structures.
For vertical supports you can use a timing of 10x10 cm or 10x15 cm. Horizontal crossbars and rafters make 3-4-centimeter thickness from wooden boards.
Procedure Next:
- vertical supports are installed. Due to the fact that the design will continue to be dismantled, we offer to use the following option: You retreat approximately halfter (to work conveniently) from the external border of the future foundation, digging the pits of the 60-80-centimeter depth in the corners of the site and on its perimeter in step to 1, 5-2 meters (the width and length of the holes are 5-7 cm more of the cross section of the bar on each side), turn the lower end of each rod rubberoid to the heft height (this will not give wood supremely agrees), install the racks in the pits strictly in the vertical position, Fall asleep the free space between the supports and walls of the pit with crushed stone and thoroughly tamper. It would be possible to pour the pits with concrete, but this will create difficulties with the subsequent dismantling of the temporary protective design. In practice, the crushed stone perfectly copes with the task of it. For greater confidence, with a periodicity of a few days, check the status of the backfill, align the poles (if required) and seal rubble;
- rubber horizontal elements are stuffed. To subsequently, it was easier to disassemble the design, perform fastening with bolts / screws. Use a minimum of 2 fasteners at each point of intersection of the horizontal jumper with a vertical reference counter. Between the individual longitudinal elements, withstand the half-meter distance in height. The real need for the installation of additional internal supports occurs if the platform width exceeds 6 m. Use the internal pillars will only be used when arranging a ribbon foundation and a column support structure. In most cases, such a limitation is not a serious obstacle, since The slab foundation under the bath is poured extremely rarely and its arrangement is better to postpone until the heat arrival;
- mounted rafters. The procedure, recommendations for the use of fasteners and a step between the elements of the system remain similar to the previous item. Internal backups, as noted, do not apply - tarpaulin weighs relatively a bit and the existing framework will cope with the loads created;
- framework is performed. The tarpaulin or awning is attached to the boards throughout the external perimeter of the erected design. To fix the material, use a building stapler with brackets, minor nails or other suitable fasteners. Crepe to horizontal boards with a step of 40-50 cm. Do not forget to leave an unfixed place to enter.
Helpful advice! For outdoor skin, use a tarp length that exceeds the height of the walls by 20-30 cm. Free part of the material at the bottom you will fit to the ground by installing bricks from above, building blocks and other suitable items. This will be minimized by the injection of the finished design.
An even simpler embodiment of protective shelter, perfectly suitable for isolation of small reference sites, is considered in detail in the section "Foundation for 20 days: video selection" in the appropriate lesson.
Organization of additional heating of the foundation
In the complex with the elevated protective tent, special equipment is well shown, which allows maintaining the temperature inside the tent at a higher level, compared with the street.
The most simple and easy-to-use option for such equipment is a heat gun operating on gas. This system looks like this.
Gas heat guns are autonomous air-heating equipment, which is used for fast and efficient heat distribution.
The heat gun works on the principle of a conventional heater:
- the device is connected to the source of energy (in this case, the gas cylinder protrudes as such);
- the unit begins to work;
- the air temperature rises.
The use of a thermal gun has a significant drawback - its work is inevitably accompanied by relatively large financial expenses.
For example, the use of a 10-kilowatt unit allows to increase the air temperature inside the tent with an area of \u200b\u200b100 m2, a maximum of 10 degrees compared with the street temperature. In such conditions, the gun will burn up to 20 liters of gas during the day.
If the street is colder -15 degrees, for heating the site of the specified area there will have to use a power gun of about 30 kW. Gas consumption, while will increase threefold. In the monetary equivalent, costs will be about 1000 rubles per day. Operating the data given, you can calculate the cost of heating the support base in your case.
Gas heat gun Heat-cannon, 30 kW
Characteristics of guns
Are such financial investments are appropriate or better to wait for heat offensive - in this matter, each developer must decide on its own.
A good alternative thermal cannon is a special transformer designed to warm up concrete structures.
Important! Do not attempt to connect the transformer yourself without having appropriate skills and qualifications - it is dangerous for life. It is better to initially turn to an experienced specialist and protect yourself from possible tragic consequences.
The electrodes are connected to the transformer one end, the second to the valve in the step of the order of half a meter. To such work, a qualified master must be brought to be attracted, capable of correctly mounting the electrical heating system and ensure control of its functioning in the future.
Any errors when using the transformer can lead to the defeat of workers engaged in the construction of the foundation, electric shock. To minimize risks, 36-volt equipment applies.
The price of heat gun
heat gun
Summing up
Conclusion from the foregoing as follows: Concrete can be poured in winter, but only if there is justified necessity, because This technology has a number of shortcomings.
If preference is given to the winter concreting exclusively because of the desire of the developer to save on third-party workers, you need to think about several times, because According to the result, the imaginary savings can turn into additional costs when carrying out earthworks, insulation, the construction of protective shelter and the organization of heating.
Concretion in the summer period of the year takes much less temporary, labor and financial resources. If the fill of the foundation in the winter is the only possible option, perform work in strict accordance with the recommendations received.
Foundation for 20 days: video selection
For a better understanding of the process, we suggest you familiarize yourself with the video selection, a phased illustrating the process of independent arrangement of the foundation.
The first day. Marking
Second day. Excavation
Day Third-fourth. From pillows before reinforcement
Day of the fifth six. Continuation of the arrangement of the internal layers
Seventh-eight day. Important issues of waterproofing
The day is the ninth-tenth. Learning to work with level
Day 11-14. We do warmly
Day 15-20. Complete work
Video - how to fill the foundation in the winter
Filling the foundation in winter is a time-consuming and technically complex type of work, requiring careful preparation and accurate compliance with construction regulations. Until recently, the construction of the base of the house at a negative air temperature was impracticable due to the lack of conditions necessary for the natural curing of concrete. With the advent of new technologies, the fill of the foundation of buildings in the winter has become easier and more affordable.
Nuances of concreting in winter
The basis of the maintenance of the concrete mix - hydration, which is accompanied by the transition of a material from a liquid state into a solid monolith. With a favorable level of humidity and the average daily temperature above 0 ° C there is a gradual set of strength of the base of the house. In winter, instead of hydration, water crystallization occurs, which prevents the formation of durable molecular bonds and increases by 10% the porosity of the concrete mixture.
As a result, the strength of the foundation is significantly reduced and does not reach the planned level. Is it possible to fill the foundation in winter? Yes, if you use one of the developed methods of fabrication at low temperatures. The choice of a specific option depends on the following factors:
- climate nuances during low temperatures;
- dimensions of the house;
- opportunities to increase the temperature of the water and aggregate.
The grade of the cement used, the subtlety of its grinding used is also important, the chemical composition and proportion of the components of the solution that helps slightly increase the temperature of the mixture during the natural hydration process.
It is allowed to warm only water and aggregates, since a similar effect with cement impairs its binder properties.
Why do you need to build the foundation in the winter? In private construction, such a need can be caused by the following reasons:
- Construction of a house on areas with a soil, prone to squeezing. In winter, the soil is frozen, keeps the form well and allows you to make a pit without much effort.
- Building a building in territories with harsh climatic conditions. In this case, the warm period is short and not always suitable for mounting the foundation for subjective reasons.
In some cases, the construction of the founding of the building during frosts is justified by low prices for materials and the presence of free time in developers or owners of future real estate. Among the disadvantages of the foundation of the foundation of the house in winter, it is possible to highlight the need for special techniques for rolling trenche, a small performance of work and additional heating costs and the acquisition of additives.
Foundation technology in winter
When the foundation of the private house is erected under low temperatures, it is advisable to use a concrete mixture with modifying additives, and at the end of work, it is covered with heat insulation design. Other methods of time consuming and require special skills.
For the construction of the base in the winter, the following is necessary:
- concrete solution;
- modifying additives;
- crushed stone;
- rods or grid for reinforcement;
- building level;
- materials and tools for making formwork;
- shovel;
- thermal insulation;
- concrete mixer.
At first, around the perimeter of the dug trench make the formwork and set the reinforcing frame. Then the concrete solution is mixed, adding special components to it, poured the foundation of the house and leave for 3 days. During this period, the mixture is hardened, after which it should be insulated.
At temperatures below -20 ° C and humidity 60% and more work on the construction of the foundation are not conducted.
Simple ways to fill the foundation in winter
There are three directions of creating conditions for harvesting foundation: heating solution and formwork, as well as the introduction of modifying additives into a concrete mix. Each of them has its own characteristics and specifics of application.
Heating solution
If it is required to fill the foundation in the winter at a positive daytime temperature and light freeze at night, it is advisable to use the method of separate heating. With the help of heat gun or gas burner, the aggregate, water or concrete mixture, perform certain conditions.
Among them can be allocated:
- the maximum allowable water heating temperature should not exceed +80 ° C;
- the preparation of the solution is starting with water aggregate, followed by gradual administration of cement brands M400 and M500;
- making supplements that reduce the time of secreting concrete.
To obtain a mixture with a homogeneous structure and high density, vibration equipment can be used. It reduces the air content and reduces the porosity of the material. After completing the fill, the foundation of the house is covered with insulating mats, bags or tarpauloscent and maintain a temperature to a base of base strength. Then make a platform, compliance with the rules for holding concrete work during the low temperature period.
Fragrance formwork
With minor negative temperatures, the thermosa method will be effective without warming up heat sources, which involves the heat insulation device around the formwork. To do this, the insulation is placed on all sides of the base, securing the pre-vapor barrier material. It performs two functions: passes evaporating moisture from the concrete surface and protects it from penetration of precipitation.
Use additives
The introduction into a solution of modifying components contributes to an increase in thermal energy produced by concrete during hydration. Also, special additives reduce the level of water crystallization, as a result of which the maintenance of the foundation of the house occurs at a lower temperature. For the formation of frost resistance to the solution, calcium chloride, sodium nitrate, potash.
To properly clarify the base of the building, you can combine concrete with modifying components and artificial heating.
Technically complex methods
In addition to the natural heating of a concrete mix when filling the foundation, artificial methods using electrical devices can be used. These include:
- Concreting by the method of thermos. Around the formwork make the insulating trim, which is a metal body with a water, steam or electrical circuit to warm the concrete. This design prevents heat loss and reduces the rate of cooling the base.
- Concreting with electrical heating. It is performed using a current, which is allowed on the wires laid under the pouring of the solution. The cable can also be emuldrated by reinforcement or formwork. This option of concreting in winter is the simplicity of performance and low costs.
- Infrared and induction heating. In this case, the source of heat is used by the heat, special emitters or cable, which contributes to the creation of magnetic fields in the formwork of steel or reinforcement. This option to maintain the desired temperature of the solution requires special devices and complex preliminary calculations.
- Pouring solution with steam heating. This method is characterized by high labor intensity and is carried out using powerful equipment and a large volume of water. In the design of the formwork, the pipes are installed, combining them into a single system for supplying steam and heating the foundation.
- Building warmth. The device of such a design refers to costly heating methods. First, around the foundation of the house you need to build a tent from tarpaulin or polyethylene, and then maintain inside the desired temperature with heat guns, electrical devices or portable stoves.
The use of technically complex methods of heating requires significant financial investments, so the effectiveness and necessity of the winter fill should be evaluated.
Requirements for construction work
To ensure the strength and reliability of the foundation of the house when it is filling in the winter period, some rules must be followed. First, it is impossible to carry out work with parts with large intervals between each fill. The concrete solution is placed in small segments, quickly overlapping them with the following layer. This avoids the loss of heat and makes the temperature differences are minimal.
Check out the video, what moments need to be considered when the foundation is filling.
In addition, it is also necessary:
- carefully clean from the snow prepared trench and remove from the reinforcement and the bottom of the ditch to the resulting score;
- cover the withlerting material;
- pre-warm the bottom between the formwork walls;
- ensure pass to formwork.
It is forbidden to pour concrete on top of the soil frosted, because when thawing it will settle and can cause the foundation.