Do-it-yourself method of pouring concrete in water. underwater concreting

The role of water in concrete is actually very huge. It performs the functions of not only a solvent, but also a chemical reagent, without which concrete simply cannot be plastic, and also cannot harden. You need to know that the water in the concrete must have good quality, i.e. it should not be cloudy, should not contain impurities, chlorine and other coarse substances that give it an unpleasant odor.

The temperature of the water is also important. If it is made, for example, in winter, then the temperature of the liquid should be approximately 40 °, no more. If this is a warm season, then, accordingly, the water should be cold. These conditions are necessary for optimal concrete setting.

If we consider how water interacts in concrete in more detail, then we can say that it is needed to provide the composition:

Reactions with astringent;

Turning it into a monolithic mass.

Of course, the amount of water must be strictly calculated for each brand of concrete. This parameter should be such that no excess water remains during the reaction with the binder. Otherwise, after the mass becomes monolithic, voids form in it.

What water is suitable for concrete?

Most people think that absolutely all water is suitable for concrete, i. You can take it from any source. However, this is not at all the case. The requirements for water in concrete are not the most stringent, but if they are not met, the consequences may not be very good.

Drinking water.

Drinking water can be used for concrete, it does not require testing.

Ground water.

Ground water can be used for concrete, but after verification.

Technical water.

Industrial water can be used for concrete, but only after verification.

Sea water.

The use of sea water is only suitable for non-reinforced concrete.

Wastewater.

The use of wastewater in concrete is not possible.

So, we can conclude that the water for the concrete mixture can be taken from trusted sources or one that has undergone chemical analysis in a specialized laboratory.

Some buildings or structures cannot be built on the ground. When building a hydroelectric power station, construction in the water cannot be avoided. But will concrete harden in water?

In this article, we will explain how concrete is poured into water and how it will build a strong building even in the most unsuitable conditions.

Concreting in water: principles and characteristics

Water is not a hindrance in the construction of a concrete building. However, there is the necessary conditions, without which the concrete will not harden - for example, the foundation must be completely dry so that it does not erode over time.

There are two ways to concrete a building in water:

at a shallow depth, where there are no ebbs and flows, and the current is relatively stable, it is possible to pour concrete by lowering the concrete mixture through a funnel into cavities fenced with lintels by piles. Or to make a direct pouring of concrete into the water;

to place concrete at a great depth with a strong current, it is necessary to use caissons. The concrete mass in the caissons is best placed not manually, but with the help of concrete pumps.

Let's look at these methods of pouring concrete under water in more detail.

Concrete Pouring Mold: Pile Method

In the place where it will be necessary to erect the necessary structure, sheet piles are installed. Thanks to this, you can skip the stage of drainage work. After you make sure that the piles are fixed tightly enough, concrete is poured into them through a funnel.

Pay attention to the preparation of the concrete solution. In order for the concrete to fit well, it must be allowed to harden a little. If it becomes viscous enough, it will not be washed away by the current and will lie tightly in the piles.

Concreting in water

At the site where the building is planned to be built in the future, two ditches must be dug with the help of dredgers. In these ditches it is necessary to pour half-hardened concrete, directly into the water. As a result, two shafts will be obtained, which will allow the structure to reach the currents of low waters.

After that, iron piles are driven into the shafts, which will hold this structure. The piles must be fastened together with iron rods. To keep them in place, it is necessary to attach them with a steel cable to the dead anchors.

Concreting in water is an important stage in the construction of hydraulic structures. If you need advice, they will be happy to help you create a high-quality and strong structure even under water.

Modern construction is hard to imagine without the construction of elements of a building structure under water. Often such work is carried out during the construction of a dam, a well, and other underwater structures that penetrate to a depth of up to fifty meters.

Is concreting in water possible?

During construction ordinary house, a prerequisite will be the absence of water at the bottom of the foundation pit. Groundwater level plays an important role during concreting. Industrial construction of structures under water is possible. Such an operation is performed during the construction of breakwaters, piers, and other structures of hydraulic significance.

Types of technologies and their description

There are two ways to pour concrete mixture into water. With a shallow depth and low water fluctuations, with the help of lintels - piles, a fence is created, which is poured with a concrete mixture. Also, in a calm, shallow place, you can pour the solution directly into the water.

In a deep-water place, construction is carried out using an air chamber that provides water tightness - a caisson. The chamber is filled with a solution using a special pipe.

With the help of piles

For the construction of a concrete structure in water, sheet piles can be used. Piles are building elements of a sheet piling row - an empty pipe or a pile with a locking system of connection: tongue and groove. This method allows you to build a solid structure with a maximum depth of fifty meters.

Before work you need to prepare:

• solution;
• installed row of piles;
• lifting rope;
• pipe;
• funnel for loading the solution;
• lift.

Initially, you need to prepare the construction site above the construction site. A lift is installed on it, to which a pipe with a cross section of more than twenty centimeters is hung. For uniform and correct pouring of the mixture, the lifting cable with the workers must be quickly raised and lowered. Accuracy should be less than three centimeters.

The pipe is filled with a bag that does not allow water to penetrate and wash out the solution. The mixture is fed into the bag through a funnel - the base of the pipe becomes heavier, squeezing out water. The pipe is filled tightly, completely. The technology is characterized by multi-level concrete pouring. Each level has an unreliable top layer where water can get in, so the top layer is removed before the next level is built. A larger gap is filled with concrete using several pipes with a large cross section.

The solution should lie down to dry a little. it is possible to ensure a small loss of the mixture washed out with water. During the drying of the solution, it should be covered with a tarp from the sun or rain. If the weather allows, you can not cover. The technique, which used piles, was first used by the British engineer Kinipple. The solution is applied in different densities. A more saturated one is used to create a shell 1 m thick, the core of which is filled with a less saturated solution.

Concrete proportions:

• unsaturated composition: 6 hours of crushed stone * 1 hour of cement - can be cured for five hours;
• saturated composition: 7 hours of crushed stone * 2 hours of cement - in the air for three hours.

The time after which it is necessary to mix the mortar and when it is worth pouring depends on additives - hardening accelerators in concrete. The mixture is suitable for pouring if it is not eroded by water, binds well with the total mass, fits tightly, turns into a monolith. Places subject to frequent sailings, wave impacts, oscillations are concreted with a mortar with the addition of fast-setting cement to the composition. To make the solution become a dense monolith, tamping is used. It is carried out carefully, without unnecessary fluctuations in the water.

The composition of the solution: 1 hour of cement * 2.5 hours of sand.

Caisson method

The construction of the foundation in a caisson way is used as a solution to problems:

• water on high level and it is difficult to reduce it;
• soil includes hard rocks;
• there is a risk of uplift of the base soil;
• waves, strong undercurrent.

• camera;
• caisson structure;
• Gateway.

Most often, the caisson chamber is reinforced concrete, metal. The type of formwork is determined by the size of the plot. In a small construction area, a finished caisson is usually placed using a lift. The prefabricated caisson chamber is used for construction works larger scale.

At the bottom, a large pit is made, lined with bags of concrete. The composition, when solidified, will turn into a monolithic base. Metal piles are installed around the base, at an angle directed to the external environment, creating slopes. Inner side piles are finished with wood (board width - 5 cm) or metal (0.8 - 1 cm).

Piles are connected with metal rods, which create rigidity and strength of the pile structure. The structure is attached to the bottom with cables and anchors. The construction is carried out with the help of special equipment, qualified specialists.

The technology of laying concrete mix by the caisson method involves the use of a pipe with two valves at the edges. When concrete is supplied, the top valve opens, the mortar is poured, then it closes. The bottom valve opens while the mixture is at the point of concreting. Due to the necessary pressure inside the pipe, the concrete composition is pushed out of it. The maximum depth of such works is thirty meters.

An important component of the construction of the building is the construction of a reliable, strong and solid foundation. The basis of the structure is the foundation that holds the load of the entire building and proportionally distributes its pressure on the soil. The strength and durability of the constructed building directly depends on the constructed support, making it immune to cracks, warping and warping of walls, window frames and door jambs. For an error-free foundation design, it is necessary to take into account the landscape, soil structure, The groundwater, the degree of freezing of the earth layers. But the main stage is considered to be pouring, and most novice builders are wondering if it is possible to fill the foundation in parts?

So that the quality of the foundation being built does not decrease, it is important to correctly determine the intervals and setting time of the mortar from concrete. The process of solidification of the working mixture includes setting and hardening. The duration of the processes and their parameters depend on the brand of concrete.

The setting of concrete mortar is First stage after laying the working mixture. At this stage, it is important not to touch the poured surface, so as not to damage the structure and not spoil the quality of the setting. It will take at least three hours to connect the individual components of the solution at an ambient temperature of more than 15 degrees Celsius.

The upper setting time interval reaches 24 hours at negative temperature air. Thus, concrete setting will be faster at high temperatures. environment. It should be understood that the setting of the mixture occurs only on top layer, in the middle the solution remains liquid. Pouring in layers for 8 hours allows you to lay a new layer of thin concrete on top.

Concrete hardening lasts about a month.

The hardening of concrete occurs after its setting and lasts for a month. After 30 days, the solution finally hardens and is able to withstand various loads. The need for such a long period is due to the use of a thick layer for pouring foundations. The next layer of concrete is poured in the process of hardening only on the third day, until this time it is impossible to touch the poured concrete. Because it can crack.

Cracks on the surface are not always visible, but they are, which means they can manifest themselves at the end of the construction of buildings and structures. Thus, laying the working mixture in two layers should take no longer than 8 hours in the cold season, no more than four hours in the autumn and spring, and no more than three hours in the hot season. Laying subsequent layers should be carried out on a flat, cleaned and dried surface.

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Laying concrete in parts requires not only observing time intervals, but also pouring methods, of which there are two: block and mortar laying in layers. With a strip foundation with a filled trench underground, the laying of the working solution in the formwork should be carried out exclusively on the ground. This method will allow you to pour the mixture evenly end-to-end. With a monolithic strip foundation, block laying of the mortar should be carried out. In this case, the seams will take a perpendicular position relative to the block joints.

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Methods for pouring the foundation in parts

Filling the foundation in parts.

There are several ways to lay concrete mortar, which depend on the time of the planned pouring. If the concreting process is stopped for less than 12 hours, then the laying of the mortar will consist of several parts. At the end of the laying of the part, the finished surface should be covered with roofing material or a film that will not allow the solution to dry out. Before proceeding with the subsequent laying on an already filled surface, it is necessary to remove concrete milk from it.

Laying the mortar on the part of the mixture that has not yet hardened is called the “hot seam”. If the interval between laying the mortar exceeds 12 hours, then it is necessary to wait for the final hardening of the previous poured surface. If this advice is neglected, then a crust will form on the laid concrete, under which the mixture will not have time to harden. When a new solution is laid on the crust, it will begin to crack under pressure, which will lead to undesirable consequences in the further operation of the foundation.

Layers when pouring the solution can be vertical and horizontal. The latter are laid at ½ half the height of the formwork and do not need to be demarcated. It is important to take into account the seam when laying the mortar, it should not be in the place where the reinforcing thread stands, it should be laid below or above the steel wire. Vertical pouring requires the formwork to be separated using partitions.

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Partial pouring process technology

For the construction of a strong monolithic structure, concrete should be workplace feed continuously.

The mixer machine will ensure uninterrupted pouring of concrete.

This supply will be provided by a mixer machine, which will speed up the concreting process and simplify it. The mixer with concrete contains eight cubes of the working mixture, it is delivered to the construction site for further work. However, it is not always possible to carry out concreting in one step. The reasons for this are different: a machine with a concrete mixture is not supplied on time, there is not enough daylight hours, or the mixture is prepared by oneself in a special concrete mixer, which requires time, which means that it will not be possible to carry out concreting in one day. Therefore, it is necessary to lay the working mixture in parts.

Before proceeding with concreting, it is important to prepare the formwork, it is installed around the place to be poured. When the formwork is fixed, the concrete composition begins to be poured into it. A mixture of concrete can be prepared with your own hands or purchased at hardware stores. But in the first and in the second case, it should be diluted with water. Therefore, it is important to monitor the amount of liquid poured in, because the brand of concrete will directly depend on it. The solution should resemble sour cream and not be too watery, otherwise it will take a long time to solidify even at positive temperatures.

After concrete mix prepared, you should start pouring it. It is poured into the formwork evenly in one stream. If you pour liquid on different sides, then the foundation will not be even. When the mortar is laid, it should be leveled and compacted. The sealing of the filled surface is carried out with a special tool, with which vibration waves are created. In the absence of such a tool, you can use an ordinary wooden plank, but you should not expect an ideal effect from it. Compact the mixture until the air bubbles are gone from the mixture.

Before proceeding with the subsequent concreting, it is necessary to withstand the time interval, this applies to the horizontal method. When the area is flooded, it must be covered special material which will protect the laid surface from precipitation and direct sunlight.

Plasticizers are added to concrete to improve strength.

To improve the strength characteristics of the concrete solution, plasticizers can be added to it. Their use eliminates vibration of the poured surface and reduces the pressure from the new part of the concrete on the previously laid one. In order for the result of the additives to be positive, it is important to observe proportionality when adding them to the mixture.

In order for the filled surface to be strong, reliable and free of cracks, it is important to adhere to the following recommendations:

• It is important to plan the steps of the process.
• The area where the work is planned should be divided into sectors.
• Based on the plan for laying the mixture, distribute its volume, which should be submitted to the construction site.
• Laying the working mixture should be carried out evenly over the entire surface.
• To maintain the strength of the base and avoid seams, time intervals must be respected.
• When pouring the foundation of buildings in parts, it is important to take into account the recommendations for reinforcement.

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The main mistakes when pouring the foundation in parts

To build a solid foundation, it is important to follow the recommendations and avoid the following mistakes:

• Some builders do not consider it necessary to think over a pouring plan and start the workflow right away. A prepared work plan will save valuable time and eliminate downtime, which means that it will be possible to complete the concreting on time.
• Another mistake is the uneven laying of the working mixture over the entire area of ​​\u200b\u200bthe site.
• Using the “cold joint” method, builders do not clean the previously poured surface from cement laitance. You can remove the cement film with a hammer or a chemical composition.
• Using the "hot joint" concreting method, the poured surface is not covered with roofing felt or film.
• AT winter period time, the concrete surface is not cleared of ice or snow.

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Conclusion

In order to pour a solid, reliable foundation in parts, which will serve as the basis for buildings and structures for decades, it is important to follow the recommendations for laying concrete in this way. The main condition for a strong foundation is a high-quality solution, which must be made based on a strict ratio of the necessary components.

Laying the mixture in parts is not difficult, but its implementation must take place taking into account time intervals.

Hello! Recently, holes were drilled under the foundation 1.5 m deep, for a log house 6x6 the next day water (loam) appeared there. We are going to cover the hole with roofing material and fill it with concrete. Do I need to pump out this water?
Can someone tell me how to make an extension at the bottom without a TISE drill and is concrete M150 suitable?
Thank you all in advance. I'm looking forward to your answer, we plan to do the foundation on May 9th.

Concrete M150, if so, will do. A bayonet, or better a vibrator, is a must. Concrete is better on crushed granite, however, you can’t always guess it.
The water must be pumped out. Roofing material to the bottom, not at all necessary, will not help from anything.
The expansion at the bottom can be done with a narrow spatula with a long handle. Somewhere already about it wrote.

Dear comrades, I think you are muddying the waters.

1. About fittings. After the foundation is loaded, it turns off from work. Those. practically not needed.

2. About the brand of concrete. She didn't get hurt much. water was pushed out of the well by concrete. Those who wish can conduct an experiment: take a tin can, fill it with water, and then pour concrete into it. You will see everything yourself. In general, for a TISE pile, it is not the brand of concrete that is more important (M50 is enough for loads), but frost resistance. Even if part of the water is mixed with concrete at the very bottom, this will not greatly affect

3. How is the grillage connected to the pile? It is enough that when pouring, the pile will “sink” in the grillage by 1-2 cm. If the house is not on a slope, then no horizontal forces are applied to the grillage. After all, you don't tie the bricks with vertical reinforcement when you lay the wall, do you?

The lack of a shirt is a big omission here, I fully agree.

Reinforcement is required for a columnar foundation!
Two examples know of breaking pillars in the ground. Plus, the freezing of the earth does not necessarily go evenly, which means there will be transverse loads. Moreover, their size can be even higher than the longitudinal one and 1-2 cm, by no means, will they hold the bunch of the grillage with the pile. If there really are no issues, then you need to drill into the piles. I don’t know the depth exactly, but it depends on the thickness of the reinforcement. With a reinforcement diameter of 16 mm, the depth was 160 mm.

Please tell us more about breaking the pillars. Why did this happen and what were the consequences?

about horizontal forces. Even if the earth passes through unevenly, let's not forget that the pillar is covered on all sides by the earth, which resists compression.
In addition, there are a lot of photos of pillars without releases on the Internet and nothing seems to have happened.

For horizontal forces. I didn’t go into what was happening there, maybe it really doesn’t freeze evenly, but I repeatedly saw how the piles stand like a fan (for example, a heating main in a lowland). Maybe the post is trying to bulge, it is loaded from above, so it is looking for a weak spot, if the side is a weak spot, then it will go there.

Here, another reason is possible - the unevenness of the soil around the pillar - stones, sand, water. Void spaces not covered with soil after digging holes can be affected. Where the soil is less dense, the slope of the stob will go there.

Most good example the rupture of the pillars was at a neighbor's house. The building is 15 years old. Every year, the roof and floor of its terrace, standing on separate pillars, rose by 10-15 cm by the end of winter, and unevenly. The "autopsy showed" that at a depth of 30-40 cm from the surface, both pillars had cracks. I do not deny that the concrete was of poor quality, but the fact itself. After casting new "correct" 😀 pillars, the problems disappeared.

Hi to all who answered! I am inserting a photo from my construction site, where you can see the foundation.
()

Can concrete be poured into water?

• Caisson method;

• Concrete mix (two types);
• Pipes;
• Traverse;
• Hopper.

Caisson method

• Concrete mixture for pouring;
• Caisson (formwork);
• floating crane;
• Anchors with cables

Is it possible to pour concrete into water.)

From the subject, I think it's not entirely clear what I'm talking about, I'll explain:
Now we need to make concrete columns for the foundation using the TICE technology.
We drilled a hole in the clay with a depth of 1.5 m. With a diameter of 25 cm.
In a couple of minutes, water runs into the hole 0.5 m from the top.
And what to do?
Wait until it goes away or pour?
If poured, the water will understandably be forced out, but how will the concrete harden in this puddle?

Discussion closed by moderator

generally speaking, it is necessary to dig drainage around the field of pillars and pump it out of the drainage into the distance. True, then the charm of the pillars disappears, maybe it was possible to pour the tape.

And you don’t need to put a top water into the hole. Not much will flow from clay :) Any water-retaining formwork. If you are too lazy to dig around, you can drive in a ring of tin or insert a piece of pipe into the neck of the hole in close contact with the clay. Pump out the water.

Re: Don't put water in the hole. From clay > not much will flow :) Any water-retaining formwork. Ate too lazy to dig around,

Dig a meter and a half too? Difficult..

you can drive a ring of tin or insert a piece of pipe into the neck of the hole in close contact with the clay. Pump out the water.

The problem is to find a work of suitable diameter ..
The main thing is not even this - the shape of the hole is a dilindr with an extension at the lower end. The diameter of the expanded part is 2 times the diameter of the pipe. Down there, you certainly can’t close anything from the water. It flows very quickly, right in front of your eyes.

> If it will be poured into a pipe (plastic, ats), you can simply wrap a temporary nipple on it from an old rag and pump out the water to pour concrete.

It cannot leak from clay. Leaks from soil/clay boundary. In this place, it is necessary to isolate, for example, with a leaky bucket without a bottom.

I’ll find a photo - I’ll post it as it flows from a cut of clay at a depth of 1.5 m
those. svethu 1.2m of clay, I don’t even know how much clay from below, but water flows in the middle

Sources:

When is the filling monolithic foundation, there is a need for large volumes of concrete, which sometimes exceed several cubic meters. Construction companies are approaching this issue using heavy equipment such as concrete pumps and mixers. They allow you to mix the mortar and feed it into the formwork.

Why Layer Fill

Private developers do not always have the opportunity to use such equipment, because it is quite expensive, and for small areas such an approach may not be acceptable due to the lack of access roads for equipment. This problem can be partially solved with the help of a concrete mixer, but the volumes of the mixture that can be prepared in one load are limited. In this case, builders are wondering if it is possible to fill the foundation in parts, because this sometimes affects the strength of the foundation and its operational properties.

Concrete maturation

Concrete is a mixture of aggregates and cement that is mixed with water. Plasticizers and additives can be added to concrete during mixing to increase fluidity, impart special properties to the mixture and increase frost resistance during mixing. At this stage, and you may wonder if it is possible to fill the foundation in parts. Pouring a liquid solution into a form called formwork implies the beginning of irreversible processes in concrete, namely:

• setting;
• hardening.

During the first stage, the solution begins to solidify, because water and cement components interact with each other. But the bonds between the ingredients remain not strong enough, and if the material is subjected to a load, it may collapse, and the solution will not re-set.

What else you need to know about stages

This phase can vary depending on the air temperature and lasts from 3 hours to a day. With a decrease in temperature, the setting of concrete takes longer. At the initial stage, it remains liquid, unchanged. If during this period a new portion of concrete is added to the formwork, then the destruction of cement bonds will not occur.

At a temperature of 20 ° C, the liquid stage will last for 2 hours, if the temperature drops to zero, then this period will last for 8 hours. The time before setting can be extended, for this the concrete is constantly mixed, but its characteristics will be improved, so you should not abuse the method.

Pouring concrete during the curing phase

If you are faced with the question of whether it is possible to pour the foundation in parts, you should also study the stage of concrete hardening. This phase will last quite a long time, as the components will gain strength over many years. The first 28 days are considered to be the obligatory period of holding the structure until curing. Hardening in this case occurs quickly, which is especially important for the first day, after which the speed slows down.

In the first hours after setting, the concrete will not have such a high hardness, and if you add one more portion, this can cause small cracks, because the load on the structure will increase. After three days, these loads do not have a similar effect on the first layers. Given the peculiarities of the maturation of the solution, it can be argued that the foundation can be poured in parts, but it is important to follow certain rules.

When a private developer asks whether it is possible to fill the foundation in parts, first he must study certain rules for carrying out such work. They say: when mixing individual batches of concrete in series, you should limit yourself to two hours or less between pouring, this applies to warm weather. If the work is carried out in the off-season, then this time can be increased to 4 hours. The strength of the foundation does not change, and the seams are not formed.

If you wondered whether it is possible to fill the foundation in parts, then you should remember that long breaks in work should not exceed three days. After a break, the base of the foundation, where it is supposed to pour a fresh portion, should be cleaned of moisture, dust and dirt. It is important to clean with a metal brush. In this case, the seam will have good adhesion.

Step-by-step instructions for pouring the foundation in parts

It is better to pour the foundation continuously, sometimes for this work they do not stop even at night. As a result, it is possible to obtain a monolithic structure, which has a high bearing capacity. But continuous pouring can only be achieved if you use a purchased mortar, which will be fed into the formwork from the concrete mixer tank. If the solution is prepared directly at the construction site, then instead of this technology, the partial pouring technique is used.

Asking the question of whether it is possible to pour strip foundation parts, you should know that, under certain conditions, such a structure will not be inferior in terms of strength to that which was formed using the monolithic pouring method. The intermittent casting technology is as follows: at the first stage, it is necessary to form a reinforcing cage, which will consist of horizontal bars. They need to be separated by vertical links. The distance between the horizontal bars should be selected according to the volume of the fill. It usually ranges from 10 to 12 cm.

If you are thinking about the question of whether it is possible to fill the foundation in parts, helpful tips should be read. From them you can learn that in the next step you can prepare a solution to pour the first layer of concrete. In this case, the formwork should be filled evenly, while the thickness of the first layer should be equal to the distance between the horizontal bars, which should be reduced by 1.5 cm. This answers the question of how it is possible to fill the foundation with parts with reinforcement. The second layer will flow under the horizontal reinforcement. Once the pouring of the first layer has been completed, you can begin to prepare the second portion of the solution, which is poured from above.

This technique should be followed until the desired base height is reached. The technology is also called layered, and individual layers will be fastened together with reinforcement. However, if the first layer has already begun to set and has reached the stage of hardening, then the second pouring can be started only after the first layer has hardened.

Many novice home masters are wondering if it is possible to fill the foundation in parts, the instructions presented in the article will allow you to understand this. From it you can learn that after pouring the first layer, when it is not supposed to immediately begin to form the second, the surface should be wrapped in polyethylene, which will prevent unwanted evaporation of water. In this case, the second layer can be formed the next day, after removing concrete milk from the surface.

If you have not had the experience of pouring the foundation before, then you first need to think about what brand of concrete you will use. In this case, it is recommended to pay attention to the operating conditions of the future design. This is due to the fact that different brands are characterized by a certain moisture resistance and frost resistance. If you are faced with the question of whether it is possible to fill the foundation in parts, what kind of concrete to carry out these works, you must certainly decide.

For difficult conditions, grades M-300 and M-450 are usually used. If the conditions are not so severe, then concrete of the M-100 and M-200 grades can be used. M-100 and M-450 are made from the same ingredients, but the recipes are different. For example, M-100 is mixed from:

• 4 parts of sand;
• 1 part cement;
• 6 parts gravel.

Whereas for the preparation of M-450 you should use:

• one part of sand;
• one part of cement;
• two pieces of gravel.

Conclusion

In order to form cement stone, the solution will require 1 part of water to 4 parts of cement. But when studying the ratio of cement and water, you will understand that the most common proportions are as follows: 3 to 2 and 2 to 1.

Concreting in water is used both in the construction of hydraulic structures (breakwaters, bridge supports, piers, moorings, etc.), and in private low-rise construction in conditions of high standing groundwater.

Can concrete be poured into water?

The answer is positive: “Yes! Not only possible and necessary! At this point in time, there are four technologies for pouring concrete into water:

• Rising pipe technology;
• Caisson method;
• Concreting using bags filled with mortar;

The first two options are used in industrial construction. The latter method is usually used in private low-rise construction.

Rising tube technology

In general, the following equipment and materials will be required:

• Concrete mix (two types);
• Pile site (flooring above the site);
• Lifting device: floating crane, hoist or winch;
• Pipes;
• Traverse;
• Formwork for fencing off the closed space of the concreting object from the water of the reservoir;
• Hopper.

The “ascending pipe” method (piling method) allows you to build strong concrete structures in water at shallow depths. On the surface of the reservoir directly above the structure under construction, on piles driven into the bottom, a working platform is being erected.

A traverse is installed on the site, to which a supply pipe with a diameter of at least 200 millimeters is suspended. In this case, the pipes are lowered and raised using a hoist or winch.

The ideal option is lifting and lowering with a floating crane, and concrete supply with a concrete pump. Depending on the dimensions of the structure under construction, there may be several loading pipes.

Is it possible to pour concrete into water without preparatory work? In no case. Before the start of pouring, the bottom of the proposed structure is covered with a dense fabric (canvas or tarpaulin) with an overlap on the formwork and leveled with stone and crushed stone filling. This is done to avoid leakage of concrete through the differences in the topography of the bottom of the reservoir.

For pouring, two types of concrete are used: “saturated” and “unsaturated”. The first is laid along the perimeter of the formwork, and the second is poured into the core of the structure. At the same time, before pouring, both types of concrete must be kept in the air, in the shade for 5 and 3 hours, respectively.

The filling process itself is as follows. The pipe sinks to the bottom of the reservoir. Concrete is fed into the pipe until the entire pipe space is filled. Further, with the help of a lifting device, the pipe begins to be raised - the concrete is unloaded to the bottom of the reservoir. The process of layer-by-layer pouring is repeated until the entire structure is filled.

Important! It should be ensured that each lower layer of concrete does not turn into stone and is in a semi-liquid state. Besides this way concreting under water is possible in reservoirs where there are no strong currents and significant unrest.

Caisson method

You will need the following equipment and materials: Materials:

• Concrete mix in bags for the base;
• Concrete mixture for pouring;
• Caisson (formwork);
• floating crane;
• Filling pipes with two valves;
• Feeder (concrete pump);
• Anchors with cables

This method is used for deep-water concreting (up to 30-50 meters), with strong underwater currents or strong waves. This requires the construction of a sufficiently strong formwork. With small volumes of reinforced concrete products, a welded steel structure (caisson) is used as a formwork, which is lowered to the bottom with a floating crane.

If you plan to fill a large object, proceed as follows:

• At the bottom of the reservoir, a trench or pit is torn off according to the size of the structure;
• The recess is filled with bags filled with concrete - the foundation of the future object;
• Along the perimeter of the base, steel piles are driven into the bottom of the reservoir. At the same time, piles are installed with a slight slope to the outside of the object, to create slopes;
• In order to avoid breaking the slope, the piles are attached to the bottom with the help of cables and anchors;
• The inner surface between the piles is sheathed with boards with a thickness of at least 50 mm, or steel sheets not less than 10 mm;
• The outer surface between the piles is reinforced with belts of steel rods, corners or channels.

For the possibility of deep-sea concreting, the supply of mortar into the pipes must be carried out under excessive pressure. This requirement is ensured by the presence of two valves at the ends of the supply pipe and the supply of concrete by a concrete pump. In all other respects, the technology of coffered underwater concreting is similar to pile concreting.

Underwater concreting with bags of cement

Bags filled with concrete mortar are used according to the type of foundation construction for caisson concreting. A saturated concrete solution is mixed, which is used to fill pre-prepared bags. Next, bags with a liquid solution (above the level of nearby groundwater) fill a trench or pit.

The structure is kept for at least 30 days, after which a formwork is erected around the object and pouring (of the foundation or walls) is carried out according to the classical technology.

Curing concrete in water is an interesting process. People often misunderstand it, suspecting that it will not produce any beneficial results. An excellent example is the recommendations of "professionals" to fill the foundation only in the dry months. They are wrong, because the material can be used under different conditions.

Water is a component of concrete

Water is one of the building mix components. It is used in a certain percentage with other ingredients to provide the desired consistency. This nuance is fundamental when evaluating inexperienced builders, who believe that with high humidity the material will lose its qualities.

The composition is based on the dilution of binders, which, after hardening, create strong bonds between themselves and with other materials. So the presence of water is not as detrimental as it is commonly believed. Its impact requires detailed evaluation for true results.

Effect of water during curing

Water has a dual effect on concrete during hardening. The process proceeds in two directions at once, but the result is unambiguous. How does the material behave during hardening?

• Part of the water is taken in;
• being forced out excess water.

Both directions are opposed to each other, but continue at each stage of the set of strength. Details will tell you how you can use the mixture with a close water horizon and in bad weather conditions.

Some of the water is taken in

When ordering M250 concrete from a concrete plant, a person receives a high-quality mixture of the desired consistency. It is delivered by special transport, so the presence of the formwork in the water does not change the density. If the technology is violated during the production of the material, the consistency becomes thick. The binders are ready to take on some more moisture, so they begin to take it from the environment. Also, the process is observed in the last week of curing, when the humidity in the room sharply decreases.

Excess water is expelled

During the hardening process, excess water is always displaced. The laws of physics dictate that a material with a higher density will replace an unnecessary component, which will provide sufficient strength. Based on this condition, today professionals use the building mixture in any conditions. The main thing is that concrete is delivered from the manufacturer after quality control, since non-compliance with GOSTs often leads to blurring.

High-quality concrete from waterproof cement

Particular attention should be paid to the quality of concrete. A large manufacturer checks the material for compliance with the requirements of the standards, so you can use the marking to determine the possibility of using the mixture. Although when working in places with high humidity or in open water areas, you can use special concrete made from WBC (water-resistant, quick-setting cement).

Building material has found distribution in the construction of monolithic bridges. The reason for this is the maximum water resistance and waterproofing after hardening. These indicators eliminate the restrictions that make it necessary to resort to additional work in difficult conditions.

If you buy M200 from the manufacturer, you can not worry about its hardening in groundwater. Checks confirm this fact, so professionals pour the foundation in any conditions. The only problem is only a slight increase in the curing time.