Concrete hardening time m200 in autumn: how long does it take for a concrete foundation to harden

Types of foundations There are a large number of different types of foundations, but they all have one thing in common. Almost everywhere, concrete mortar is used as a binding material. It is this that gives the foundation the necessary strength and reliability, but it takes some time for it to gain the necessary parameters.

It is this period that is considered key in the construction of any foundation, therefore it is strictly prohibited to build load-bearing walls on a raw foundation. First, you need to wait some time until the concrete gains its original strength, and this depends on the type of solution, the amount of water in it, even climatic conditions and pouring technology.

Therefore, it is quite difficult to say exactly how long it takes for concrete to harden.

The design and characteristics of concrete foundations provide for the necessary moment - this is the time until the concrete hardens. During this time, a chemical reaction occurs between cement and water, releasing a large amount of heat. Therefore, even in standard climatic conditions with a large number of warm days, concrete dries for at least a week, but during this time the average strength of the concrete base is achieved.

But the final strength of the structure is achieved in a much longer time, and an important factor here is the conditions for its hardening.

Under standard drying conditions, the duration of this process can be up to four weeks, sometimes even longer if the base is thick enough and consists of several separate balls (monolithic foundation). And if a columnar or strip structure is used, then the time will be significantly less.

Impact factors

To help the cement dry out and avoid various troubles, there are several factors that should be observed:

• protect concrete from direct exposure to sunlight;
• if cement suddenly loses moisture, cracks may form; to avoid this, concrete must be moistened periodically;
• in the event of an unexpected cold snap, the poured concrete needs to be heated, this can be done using special heaters, steam, electricity, etc.;
• special salt-free and salt preparations, sold in construction stores, affect the drying time of cement - they significantly reduce it;
• More expensive brands of concrete harden faster than cheaper ones.

Sometimes it happens that the drying process needs to be slowed down, if, for example, it has already been prepared, but has not been delivered to the construction site. In this case, special surfactants are used.

In this aspect, seasonality, the composition of the solution, the presence of auxiliary additives, and the level of strength of the material are important.

If pouring is done outdoors and the air temperature does not exceed 5°C, the concrete will take 2 times longer to gain strength than at 20°C. If the thermometer drops below zero, the mixture will thicken due to the freezing of water, but will not be able to achieve the desired level of integrity. Also, the hardening time depends on the proportions in which water, gravel or crushed stone filler, cement, and sand were used.

Technological additives are used in cases where it is planned to subject the mixture to long-term transportation: under such conditions, a significant slowdown in the thickening process of the solution is expected. They are also relevant if it is necessary to speed up construction work and achieve faster drying without loss of quality and load-bearing capacity.

Factors related to the strength of concrete certainly affect the speed of formation of structures made from it:

• cement and water used in certain proportions affect the rate of chemical reaction. If there is too much liquid, pores will appear profusely, which will negatively affect the quality of the product;
• The larger the filler present in the mass, the stronger it becomes when dried.

How long concrete dries depends on the coolness of the filler. Over time and as it dries, the strength characteristics of the product increase; stopping this progress is caused by a drop in temperature below zero.
To find out how long concrete takes to dry, it is necessary to take into account a number of conditions that affect the rate of concrete hardening.

Seasonality

The key factors that determine how long concrete hardens are the environment and the period of the year when construction work is carried out. This group includes indicators of outdoor temperature and air humidity.

If in summer the composition can harden in a few days, then in the cold period hardening will take more than a month. The specifics of strength gain under favorable concrete hardening conditions are as follows:

1. 1-3 days - no more than 30% brand strength.
2. 7-14 — 60-80%.
3. 28 — 100%.

If you want to make the foundation mortar quick-hardening, you need to add special additives to its composition.

Tamping

A dense screed does not tolerate cutting and drilling after compaction, so for such work it is necessary to use diamond drills. A simple tip will quickly fail.

Compound

How long the concrete hardening process can take depends on its composition. So, if it contains a large amount of porous additives, such as slag and expanded clay, water will linger in the solution for a long time. If the mixture contains sand or gravel, the liquid will come out faster.

We suggest you familiarize yourself with How to attach a cable duct to a concrete wall

To reduce the intensity of moisture evaporation and increase the strength characteristics of the composition, it is diluted with additional components. It can be bentonite or a soap composition. The introduction of such additives increases the overall cost of the work, but prevents the problem of early drying out of the solution.

Stages of composition readiness

If the developer is wondering how long it takes for the concrete to completely harden, then they will be disappointed. External factors have little effect on the rate of hardening, since this is a chemical exothermic reaction.

Moreover, it begins already at the moment of mixing the solution, because the mixture heats up sharply. But, as a rule, there is a clear time frame while concrete gains its strength, namely:

When planning the foundation for a residential or administrative building, then a number of points need to be taken into account. For example, the brand of cement used, the date of its packaging or production, storage conditions, as well as how many ingredients are needed for the solution and in what proportions to mix it. Also, much depends on the type of base chosen and the specifics of the particular soil.

As a rule, the foundation must be laid below the limiting depth of soil freezing, then it will be protected from swelling. If you decide on the types of load-bearing structures, then almost everywhere the same building materials are used: sand, cement, gravel (crushed stone) and reinforcement.

When choosing a design, you need to focus on the type of soil, the complexity and weight of the future structure, the depth of groundwater, possible horizontal and vertical loads. Concrete must be poured at an ambient temperature of +5 degrees; if the temperature is lower, then electric heating is used, because then it will not be possible to achieve the optimal rate of strength gain.

Dependence of foundation holding time on its type

Insinuations that the finished foundation, after the concrete components included in it have reached the normalized strength, should stand for a year or winter are absolutely unfounded. A common misconception about the need to withstand the structure until the end of the ongoing sedimentation-shrinkage processes arose as a result of the substitution of concepts. A fully erected building must be conditioned before finishing finishing begins. This is explained simply by the example of existing varieties of structural foundations.

Video on how to speed up concrete hardening

Columnar foundations

A columnar foundation is a series of individual pillars, for the construction of which brick or stone masonry is used; often the foundation pillars are made of concrete or reinforced concrete. To give the foundation elements additional stability, a grillage is installed - a reinforced concrete strip connecting the head of the pillars.

This type of foundation is classified as a light variety, therefore, the foundation base, not loaded with the weight of the building, is subject to increased mobility during soil movements with heterogeneous morphology, and can be easily deformed as a result of frost heaving. By definition, the foundation of a columnar structure cannot stand, and the construction of walls must begin immediately after the masonry mortar has set or the concrete has gained strength.

Strip foundations

Strip reinforced concrete foundations can be constructed in two types:

• shallow foundations are equipped for the construction of light buildings and their soles rest on soil horizons located above the freezing level;
• deeply buried options involve the construction of voluminous structures with a large weight on them; the level of their base exceeds the depth of soil freezing.

A shallow strip foundation experiences loads that are similar in tension and strength to the impact on columnar versions with a grillage. If such a foundation is allowed to stand for a period when active soil heaving occurs under the influence of freezing and thawing of ground moisture, the possibility of its deformation is very likely.

Deep strip foundations rest their base on dense horizons and are not affected by ground shifts. Shrinkage processes in the concrete mass are completely completed after reaching the standard strength, and the settlement of the structure under the influence of its own mass, without taking into account the weight of the building, is completely leveled by expansion joints.

Slab varieties

Monolithic foundations are simply calculated and arranged; they provide a foundation for the building under construction with sufficient strength characteristics. The uniform distribution of the load on the soil base due to the large supporting surface determines the minimum value of the specific pressure on the soil. A properly prepared sand or sand-crushed stone cushion under the foundation slab can prevent its significant sedimentary movements.

The stability of the building being built on a slab foundation directly depends on how carefully the preliminary excavation work was carried out. The amount of time a monolithic foundation must stand is determined, again, only by the period necessary for the concrete to gain strength.

Pile foundations

The foundations of buildings on piles, with any technology of their arrangement, ensure the transfer of load to deep, often bedrock, horizons of soils and rocks. This type of foundation construction completely eliminates the possibility of building deformation, regardless of how much time is allocated for them to stand after installation is completed.

Determining the time for how long the foundation should stand after pouring should be correlated with the time period during which ready-mixed concrete will gain the strength standardized by SP 70.13330.2012. Additional curing is not advisable, and in cases of using columnar structures and shallow strip foundations, it is even contraindicated.

When can you build walls?

There was an opinion that before installing the walls, it was necessary to allow the foundation to settle all winter without load. It was explained by the need for subsidence, then construction could continue. Now the version is more like a myth.

When a house is being built, well-compacted soil lies at the freezing depth. If the soil is subsiding, preparation is made of crushed stone with geotextiles. The preparation is loaded with the weight of the sole and the tape. There is nowhere for the compacted soil to settle further.

The walls are erected in stages, the load increases gradually. Full load of the house up to 100% occurs in 2-3 years. Experienced builders and design engineers warn that a foundation left without walls and roof all winter becomes defenseless against negative pressure from heaving soils. There is a risk of its destruction and deformation.

Within a month, the composition will finally harden and the walls can be erected. To avoid cracks and other troubles, concrete must gain at least 70% strength. Then they begin laying walls, slabs, and ceilings.

Design requirements

The concrete blind area has a fairly simple design, the preparation of which will require the following materials:

1. Bedding (pillow). This is done before pouring the solution. A variety of materials are used as backfill: coarse or medium sand, sand-gravel mixture, crushed stone, fine gravel. The foundation area cannot be laid on fine sand due to the possibility of shrinkage, since in this case there is a risk that the base will crack. It is best to prepare a two-layer cushion: first lay gravel or crushed stone, which will compact the soil, and then sand.
2. Reinforcement. The presence of reinforcing mesh for a concrete blind area will give the structure more strength. The cell size of this product is usually 30 x 30 or 50 x 50 cm. The mesh diameter should be about 6-8 mm, but it all depends on the type of soil.
3. Formwork. Wooden guides located along the perimeter of the coating are required, as they will prevent the concrete mixture from spreading. The width of the formwork boards is usually 20-25 mm.
4. Concrete solution. The blind area is poured using a specific concrete mixture composition.

Concrete classes, depending on the strength of the composition
. To obtain a high-quality coating, it is most profitable to make a concrete mixture on your own.

To fill the blind area of ​​a house with concrete, you need to familiarize yourself with the regulations and recommendations of SNiP:

• The width of the blind area should be 20 cm greater than the roof overhang (SNiP 2.02.01-83). If the structure has a drainage system, then its indicators are also taken into account. The optimal value is 1 meter. In this case, you can lay a tile path around the house.
• The length of the blind area around the house, made with your own hands, must correspond to the perimeter of the building. However, if you plan to install a concrete porch, then a “break” is allowed.
• Depth. The depth of the “tape” is half the calculated freezing depth of the ground.
• The thickness of the concrete blind area is also regulated by SNiP and, according to these requirements, should be at least 7-10 cm for the top layer. However, many people make concrete parking spaces for personal cars along with the blind area. In this case, the operational load increases, and the thickness of the concrete blind area can reach up to 15 cm.

The blind area must be built at a slope of 2-3 degrees

• Slope. According to SNiP III-10-75, the slope should be from 1 to 10 cm for each meter of width. Most often it is 2-3 cm per meter - this is approximately 2-3 degrees. The angle of inclination must be directed in the direction opposite to the foundation. It is not recommended to increase the slope, since in this case it will be difficult to walk along such a path in winter, when ice forms on the surface.
• Border. The installation of a blind area for a house does not include the mandatory production of a border, so in this case the decision is made by the owners of country property. However, experts recommend installing such “limiters” if trees and shrubs with an “aggressive” root system (blackberries, raspberries, plane trees, poplars and others) grow near the foundation.
• Base height. For a hard type covering (concrete), the base must be at least 50 cm.
• The recommended height of the blind area above ground level is 5 cm or more.

There are also several schemes according to which a blind area can be built from crushed stone, in the form of a monolithic concrete covering, both for normal soil types and for “problematic” ones.

Types of blind area, based on soil characteristics

Knowing the requirements of SNiP and the features of a suburban area, you can make a blind area with your own hands using the step-by-step instructions given below.

Impact factors

Before starting construction work, it is necessary to take into account all factors that could in one way or another influence the drying time of concrete.

Seasonality

Of course, the environment has the main influence on the drying process of cement mortar. Depending on the temperature and atmospheric humidity, the period for setting and complete drying may be limited to a couple of days in the summer (but the strength will be low) or the structure will retain a large amount of water for more than 30 days during the cold season.

The strengthening of concrete under normal temperature conditions can be better explained by a special table that indicates how long it will take to achieve the maximum effect.

Tamping

Much also depends on the density of the construction mixture. Naturally, the higher it is, the slower the moisture leaves the structure and the better the cement hydration indicators will be. In industrial construction, this problem is solved with the help of vibration treatment, but at home they usually get by with bayoneting.

It is worth remembering that a dense screed is more difficult to cut and drill after compaction. In such cases, diamond-coated drills are used. Drills with a regular tip instantly fail.

Compound

The presence of various components in the building mixture also affects the setting process. The more porous materials (expanded clay, slag) in the solution, the slower the dehydration of the structure will occur. In the case of sand or gravel, on the contrary, the liquid will come out of solution faster.

To slow down the evaporation of moisture from concrete (especially in high temperature conditions) and improve its strength, they resort to the use of special additives (concrete, soap composition). This will somewhat affect the cost of the filling mixture, but will prevent premature drying.

Additional recommendations

The advice of the experts boils down to the following:

• in order to start the hydrogenation reaction with a gradual increase in the strength properties of the solution, it is better to carry out all work in the summer. For example, in winter, the water in the working mixture will freeze and setting simply will not occur;
• optimal conditions for arranging foundations: general temperature limit - about 20 degrees; average level of humidity, normal level of pressure, protection from direct solar heating;
• moisturizing the fill can be done using damp cloth, film materials, sawdust coverings or straw. It is especially important to monitor this parameter in the first week of hardening;
• special attention should be paid to preparing the working mixture. Adhesion is formed as a result of the development of a reaction with water, so it is necessary to select the correct ratio of cement and water.

The poured solution cannot be treated with a stream of water, otherwise it will lead to damage to the surface, and the cost of correcting such a defect will be quite high. It is recommended to implement humidification by spraying moisture or diffuse watering.

How long does it take to build a strip foundation for a house?

Why do you need to calculate the drying time of concrete when constructing the foundation supports of a residential building? It's simple - if work began at the end of summer, this process (gaining the strength of the support tape) may shift to mid-autumn, which will affect the rate of drying of the structure in the formwork.

Typically, the mixture in the formwork dries in 28 days in the summer, gaining the required strength at an average temperature of 20 C, humidity within 68%. With a decrease in temperature in the autumn, the drying time of concrete in the foundation belt of a house increases from 1.5 to 2 months.

Therefore, for winter work with concrete, special recipes have been developed for the preparation of compositions for pouring building structures. In extreme cold, it may be necessary to install special formwork (warm), otherwise the solution not only will not begin to gain the necessary strength, but will not even set.

The process of drying the mixture in formwork

The initial stage of concrete drying is setting

When filling the foundation formwork for a house with a concrete composition (take a belt belt as an example), two stages of hardening are distinguished:

Setting - the concrete mixture quickly loses its mobility and plasticity, which is why when pouring house structures, it is recommended to carry out all laying work very quickly, avoiding the formation of dried layers in the formwork, in order to avoid the formation of “cold bridges” inside the structure.

Transportation of concrete to the laying site is carried out with constant mixing of the mixture. All technological operations for laying the mixture into the formwork (surface leveling, compaction) should be performed without downtime or accidental interruptions. “Cold bridges” that appear when the layers of the laid mixture dry out can affect the strength and durability of the support of the house.

Properly prepared concrete mix dries in a standard time

But the hardening time of concrete in the foundation depends not only on weather conditions. The quality of the cement binder from which the solution is mixed has a great influence on the hardening time of the mixture.

The ratio of water to cement when mixing the mortar is of no small importance.

It is very important to follow the recommended proportions if the concrete mixture for pouring the foundation of a house is prepared directly at the construction site with your own hands. It is worth noting that the drying time of monolith foundations depends on the composition of the soil at the construction site, because hardening of the mixture during concreting is a chemical process that occurs depending on the combination of components

It is worth noting that the drying time of monolith foundations depends on the composition of the soil at the construction site, because hardening of the mixture during concreting is a chemical process that occurs depending on the combination of components.

How to correctly calculate the drying time of the composition

Whether a monolithic strip foundation is used for a house or a bathhouse, the concrete mixture on average reaches complete hardening in 28 days, but the strength gain does not stop there

For a long time, the foundation will continue to gain strength, so it is very important to follow the technology for laying the concrete mixture into the formwork and caring for it

The drying process of concrete must be carefully controlled, taking all measures to ensure that it is not disrupted ahead of time. The mixture laid in the formwork must be carefully looked after - moisturize the surface of the structure, and protect the surface of the foundation from sunlight.

Watch the video with expert commentary on how to properly care for your poured foundation.

Example of calculating the strength gained

There is a certain construction formula that determines how much strength concrete should gain in the formwork a certain number of days after pouring.

Rn = R28 (lgn / lg28), where:

R28 - indicates the brand of mortar that was used when concreting the foundation.

n is the time that has passed since the day the composition was poured into the structure; the first 2 days of work are not taken into account; they are simply excluded from the estimated time.

The monolithic structure gains 70% of its strength by the end of the second week after pouring. At this time, formwork panels can be removed from some structures.

We recommend watching a video showing in detail the process of dismantling formwork systems after the foundation of the future house has dried.

Objects of particular complexity that need to be filled with M400 mortar must be left to fully gain strength for a period of up to 2 months, if the filling process was carried out under normal weather conditions.

Concrete hardening time

The vast majority of amateur builders believe, for reasons that are not entirely clear, that the concreting process is completed once the laying of the formwork is completed or the work on leveling the screed is completed. Meanwhile, the setting time of concrete is much longer than the time for laying it. A concrete mixture is a living organism in which, upon completion of laying work, complex and time-consuming physical and chemical processes occur, associated with the transformation of the solution into a reliable basis for building structures.

Before stripping and enjoying the results of the efforts, you need to create the most comfortable conditions for the maturation and optimal hydration of concrete, without which it is impossible to achieve the required brand strength of the monolith. Building codes and regulations contain verified data, which are given in concrete setting time tables.

The data contained in the official tables, of course, should serve as a guide for the independent arrangement of concrete or reinforced concrete structures. But the use of such data should occur in close practical connection with real construction conditions.

Practical part

It is important to know what strength concrete has at any given time, since this information is important when building the foundation of a house. They make it possible to understand:

To correctly answer the question of how long concrete should dry to achieve full strength gains, it is necessary to consider all the factors influencing this. First, it is important to determine the setting time. The builder must do this before starting to mix the mixture in order to avoid violations in the technology.

For cements with normal setting time, the following values ​​can be given:

Advice! The most optimal air temperature for most construction work is +20ᵒС. It is this temperature that can ensure the high quality of the finished structure.

The average time to reach 100% grade strength is taken to be 28 days. But it is important to remember that these times are based on normal conditions (humidity and temperature). Brand strength is the value indicated by the manufacturer. Depending on which GOST the plant uses for marking, it is indicated in MPa (for classes according to GOST 26633-2012, for example, B20) or kgf/m² (for grades according to GOST 26633-91 *, for example M250).

Important! The final strength value may exceed the brand value and is achieved within several months or even years. But when designing, it is the brand value that is taken into account.

According to the joint venture “Load-bearing and enclosing structures”, formwork from the foundation of a house can be removed after the concrete strength has reached more than 70%. If there is justification, this value can be reduced to 50%. To fulfill this requirement, you need to know how long it takes for the foundation to dry. In this case, temperature conditions and the type of binder are taken into account.

Several factors regarding concrete

To answer this question, we should return again to the correct use of concrete itself.

When concrete is just poured, it is necessary to leave a small distance (about 0.5 m), which is filled with sand - this is what will prevent excess liquid from accumulating and destroying the concrete structure. Plus, in winter, when water turns into ice, the moisture remaining inside the foundation can simply destroy or severely deform the entire structure when it expands. When we are not talking about the construction of a country house or a bathhouse - but about important military-industrial facilities, then the concrete is given an extremely long period of time, during which it must fully gain strength and density

This applies to various bridges, dams, embankments, breakwaters, dams - all of this requires an extremely massive foundation, and rushing in the construction of such objects is simply unacceptable due to their importance. Concrete continues to gain strength even after it has completely hardened and dried - indeed, even after construction work has resumed. Of course, this process proceeds much slower than usual and is no longer taken into account in construction.

However, this provides additional reliability when it comes to reinforced concrete or simply concrete structures. As in many other cases, temperature serves by all accounts as a reliable catalyst for the reactions that take place - that is, at elevated temperatures the reaction proceeds much faster. But under no circumstances should you abuse this knowledge; during the time it takes for the foundation of the house to dry, water and concrete have time to react successfully. When heated, the water simply evaporates - and the mixture dries out, but, nevertheless, does not harden, and the bearing capacity of the entire foundation is strongly questioned. Therefore, you need to let the chemical reaction take its course, without trying to interfere with this natural and entirely natural course of events.

Why is it important?

The question of how long it takes for a concrete foundation to dry directly depends on the concrete itself, as well as on how to handle it correctly. The construction of a foundation structure, and even more so when it happens independently, requires extreme measures from a person in the form of strict adherence to instructions and safety precautions, as well as the use of special devices. This is necessary so that there are no voids or cracks in the concrete, where moisture will subsequently accumulate, and which can lead to extremely destructive results: from an unpleasant odor to colonies of fungi and bacteria. Plus, incorrect laying of concrete in itself is incorrect construction from the very beginning, and as an option, you can simply burn all the money that should have been spent on construction and subsequent repairs - their waste will be just as useless.

So you should always remember that a good foundation leads to good and high-quality construction, the weight of the building will be correctly distributed, and there is nothing particularly to worry about.

After the concrete mixture has already been prepared, poured on top of a “cushion” of sand and gravel, and covered with a special film, all construction work should be suspended and wait until the concrete itself hardens. Moreover, it hardens quite quickly - only within a week, but the chemical reaction between this substance and water has not yet proceeded to completion, that is, the foundation has not completely set, and it is still very, very early to begin work.

How do you know when the screed is ready?

The screed is the base for the floor. Depending on the different type, it dries in about 27-28 days. After this, they begin laying the flooring. Since the allotted drying time does not always coincide with that specified by the manufacturer, you need to make sure that it is ready. This question is especially relevant if a concrete screed is made in an apartment when the heating season has not yet begun.

If you lay a moisture-proof floor covering on top of a wet base, the remaining moisture will create conditions for the development of fungus and mold. Concrete under its influence will begin to collapse, and thermal insulation will be damaged. In the future, the finishing floor covering will also suffer.

To determine the readiness of the screed, you can use two methods:

• A visual inspection may provide the answer. The screed must be uniform, with uniform color and structure over the entire surface. There should be no cracks on it.
• You can use large size plastic film and attach it to the tie using adhesive tape. After a day, the film must be removed and inspected. If there are no signs of fogging on it, you can continue working on laying the flooring.

Hardening time of concrete in formwork

Formwork is a special structure designed for creating various monolithic concrete products, including foundations. During construction, wooden or metal formwork can be used.

Formwork for concrete foundation

When creating the foundation of houses, collapsible wooden formwork is most often used.

After pouring concrete and initial setting, the formwork is not dismantled for at least a week. In rare cases, the formwork remains in place for most of the concrete hardening time. After 7-10 days, the formwork is usually dismantled. Dismantling is carried out in such a way as not to damage the integrity of the structure. If the structure was installed taking into account all the rules and regulations, then there will be no problems with dismantling.

Before assembling the formwork, it is necessary to carry out preparatory work, including digging a trench (if you plan to create a strip foundation). The mixture is prepared immediately before pouring, when the formwork has already been assembled.

How long does it take for a concrete foundation to set and dry?

The strength of concrete increases daily according to the following scheme:

• primary setting (the process begins in 10-20 minutes and is completed within 24 hours);
• hardening (this stage takes about 1 month).

At temperatures above 20 degrees, the strength of the foundation on day 3 is about 50%.

Leveling is carried out while the mixture is still liquid. Builders act quickly, as signs of setting become noticeable within the first hour after pouring.

Type of base and rate of maturation

If a specific type of foundation is intended, the following must be taken into account::

• tape systems require at least 30 days of drying;
• monolithic slabs mature within 1.5-2 months;
• block type is completely ready to continue work after 30 days;
• Pile systems do not require waiting; further construction is carried out after screwing in the piles.

Optimal microclimate conditions provide sufficient moisture in the reinforced concrete mixture. If the fill dries out, the base will not gain the design strength. The foundation can be covered with special materials or waterproofed.

How long does it take for concrete to harden?

In our time, concrete has become the main material for construction. Most often it is used for the construction of residential buildings and industrial facilities, because it is the most affordable and practical. However, when you begin “collaboration” with this material, the hardening time of concrete is a more pressing issue than ever.

What does it depend on?

The concrete hardening process lasts from one to twenty-eight calendar days. Much depends on the cement used in the work. The chemical process goes like this: the minerals in the concrete are converted into hydrous potassium silicate. In order for the material to be durable, not to crumble, not to break, it must be systematically soaked with water. Hardening concrete is “capricious”. Rapid setting is determined by several components: temperature, humidity, layer thickness (tamping), etc.

Solidification stage (for example, foundation)

Concrete strength table.

The period of complete hardening and setting of cement is not that long. One day after pouring is enough for the material to completely harden. However, the main role is still played by the air temperature at which the foundation is poured. After two hours, the concrete hardens after mixing the cement mixture with water at a temperature of twenty degrees Celsius. The end of drying occurs after three hours. Special additives will help reduce the setting by fifteen or twenty minutes.

Hardening period for several grades of concrete:

• Hardening time M 200 = two to two and a half hours.
• Hardening time M 300 = one and a half to two hours.
• Hardening time M 400 = one to two hours.

Solidification stage

In other words, the hydration stage during the period when the setting of the foundation is active (evaporation of moisture from cement concrete). The hydration process ends prematurely when moisture evaporates too actively, which, in turn, negatively affects the quality and strength of the material. The ideal time interval for the foundation to harden with the required volume of water will be one and a half to two weeks.

The period for complete hardening of some grades of concrete:

• M 200 = fourteen to eighteen days.
• M 400 = seven to fourteen days.

It is important to know that the concrete in the formwork must harden for at least a week before it can be removed without damaging the structure. But do not forget that the drying period depends on the brand of cement. A graph or table will help you figure out how long it will take for concrete to set (taking into account the temperature)

The graph and table clearly describe the temperature, brand of material and drying time. A table or graph will become an indispensable assistant in this difficult task.

Seasonality of work

A new method of thermal influence in construction in winter is the use of thermomats. How long does it take to dry at low temperatures? During cold weather, when working with concrete, the possibility of insulating the cement concrete structure from water and low temperature must be taken into account. Negative conditions, like retarders, affect how long the hydration period lasts, create problems with drying, thereby reducing the durability of structures

It is important to observe the time required for the material to reach safe stability. At five degrees of heat, the quality of concrete strength increases five or even seven times compared to twenty degrees of heat.

How long does it take to harden at thirty degrees Celsius? Naturally, due to high temperatures, the cement mixture sets faster, but this can negatively affect its strength. Intense evaporation of moisture from concrete causes hydration to stop and also reduces durability

Basically, at 30 degrees Celsius, cement concrete will harden an hour after it is poured. In hot weather, when the air temperature reaches 30-40 degrees Celsius, builders use special retardant additives. They are necessary to ensure that the mixture dries evenly. Retarders allow the material to reach its highest point of strength.

Concrete is the most affordable and practical material. Setting will take place quickly and efficiently, depending on weather conditions. Novice specialists need to know the answers to two questions: how long does it take for the cement mixture to dry; how much and what additives should be used to make the material last longer.

Tips for pouring a foundation

When choosing different types of foundation (tape, column, screw, slab), the requirements for the concrete mixture, the rules for pouring it, and condition monitoring technologies are the same. The curing times vary. At an average temperature of + 10 degrees Celsius you will need:

1. For monolithic structures and vertical reinforced elements – 5 days.
2. For horizontal structures – 14 days.
3. For staircase structures with a length of 6 meters or more – 28 days.

During design, time intervals are established for the material to harden and achieve the required structural strength. For a construction worker, it is important to comply with established deadlines and conduct an examination before starting the next cycle of work.

When working in the cold season, the hardening time of concrete in the formwork increases by 2–3 times. In addition, builders will be required to strictly adhere to many rules and technologies to achieve the required result.

The reliability, strength and wear resistance of a structure directly depends on adherence to technology and the choice of building materials. To maintain performance characteristics for a long time, special attention will be required to respect the curing time of the concrete mixture.