How To Properly Ram Sand With A Vibrating Plate

All about compaction of sand

How To Properly Ram Sand With A Vibrating Plate

Before installing foundation structures or preparatory work under the screed, as well as for laying paving slabs, it is necessary to tamp the sand cushion in order to expel the excess air from it, squeeze the fine fractions of sand grains together as tightly as possible. After compaction is completed, the sand base becomes very dense, ready for further construction work. To cope with this task, mechanized and manual methods of compacting bulk material are used.

The ways

In order to carry out preparatory work for construction, a sand cushion can be formed by various methods. Their choice directly depends on what kind of tool is in the equipment, how large the area of ​​the working surface, as well as what are the requirements for the density of the sand substrate.

There are several methods of performing work associated with compaction of sand.

  • A self-driving machine is used, which ramps sand with its wheels. Sometimes trailed-type special equipment is used, equipped with rollers for rolling, with the help of which layer-by-layer compaction is performed in several passes.
  • With the help of a crane, plates weighing up to 2 tons are dropped onto the working platform.
  • Sand can be compacted with a vibrating plate. a special mechanical device.
  • With the help of a channel or a wide bar, sand can be compacted without a vibrating plate, that is, manually.

The selection of mechanized methods of ramming bulk material depends on the convenience for the operation of specialized equipment, the availability of access roads for it and the thickness of the sand substrate required by the project. On large areas, work is carried out using self-propelled tractors, and small areas are processed by self-propelled rollers. If you need to compact the sand in a very small confined space, a manual compaction may well be suitable for this case.

In order to efficiently tamp sandy bulk material, several passes are made using a tool on the same working surface, and the tamping movements are performed in a spiral direction. this way you can be sure that there will be no untreated areas of the substrate surface. If, after compaction, the material has sagged strongly, it is possible to add sand to those areas where it is clearly not enough. For a denser compaction of sand particles, it is regularly poured with water, which helps to push air between the grains of sand.

Tamping is carried out by dropping monolithic heavy slabs, if the pillow consists of clay and sand of a dusty fraction. Such substrates contain air in their multiple cavities, which comes out to the surface under the weight of the monolith. The slab with the help of special equipment rises to a height of up to 2 meters and is dropped onto the working surface flat. This method allows you to work out the clay-sand mixture to a depth of 1.5-2 meters. Usually, this method is resorted to when preparing the foundation for the foundation of a capital structure.

The manual method of forming a sand layer is resorted to when the treated area is small, and the thickness of the sand layer is small. To solve this problem, the tool is made from scrap materials. Take a bar of wood, a wide base in the form of a wooden or steel plate is attached to it perpendicularly. The attachment points of the two parts are securely fixed using hardware fasteners or a welding seam. The result of the work should be a solid construction for manual labor. It has a lot of weight, but a person is able to lift it and perform frequent blows on the sand. To work more efficiently and faster, the horizontal plate is specially weighted with the help of additional metal plates or pouring from cement.

What is it and what is it for?

When building a house for a foundation or screed, it is necessary to make a hard layer in the form of a lining of sand or gravel with fine dispersion. The tamping technique allows to provide the necessary density to such a base. To compact bulk materials, specialized equipment is used, and if the coverage area is small, a manual method of work is used. A dense sand cushion is necessary before starting construction work for the following reasons:

  • For full leveling and increasing the degree of rigidity of the base surface of the future construction being built;
  • To prevent the destruction of the foundation structure under the influence of moisture or low temperatures, when the soil begins to swell from excess water;
  • To prevent the curvature of the structure from the action of bending and compressive loads on it during the processes of soil shrinkage;
  • In order to eliminate hidden voids filled with air;
  • For the construction of an intermediate stable layer formed between the soil and the foundation structure.

Compacted sand creates a dense and durable layer, which is a reliable base for laying asphalt pavement, paving slabs, and building foundations. A properly formed sand layer is not subject to deformation and does not collapse if stepped on. Compaction technology implies performing these works in multiple passes over the entire surface of the sand layer.

How to ram properly?

In order for the frame of the building foundation to be strong, the sand area must be perfectly flat and very dense. This effect is achieved due to the fact that with a well-executed ramming, the substrate is guaranteed to have the necessary shrinkage. Whether it is true or not, after completion of the work, the result must be checked. Quality control of work is carried out with a rope pendulum or level.

To properly and with high quality compaction of sand with a vibrating plate, the following important nuances should be observed:

  • The vibrating plate will show its effectiveness if the thickness of the sand layer does not exceed 0.6 m;
  • Before starting work, the sand layer is soaked evenly with water, but this must be done evenly and without frills;
  • On the working surface, it is necessary to perform 5-7 passes in both directions.

For arranging garden paths, before building a garage, before installing the foundation of a country house, a sand pillow is often prepared manually. Sand ramming can be done with a vibrating plate or manually. Self-preparation of the surface will cost much less than hired craftsmen.

Consider how manual sand compaction is performed.

  • They purchase a ready-made or independently make a device for manual tamping of a T-shaped type. a horizontal plate is made about 30×30 cm in size, and its weight should be at least 15-20 kg. For the convenience of work, 2 handles are attached to the handle bar on the sides. these grips are needed so that the device can be lifted with two hands at once. If the ramming structure turns out to be too light, it is additionally weighted down with metal or cement.
  • With the help of a self-made tool, uniform and repeated blows are applied to the working surface of the sand mixture. With the help of these blows, it is possible to achieve the removal of voids and air, as well as to compact the sand fractions together. Tamping is performed layer by layer. when 1 layer is tamped, the next portion of sand is poured on top of it.

The process of tamping sand is not so difficult, but quite a crucial stage in construction. The success of all further work depends on the quality of its implementation, so you need to approach it carefully and conscientiously.

The following shows the compaction of sand.

How to properly ram sand and crushed stone with vibrating plate?

When compaction of the sand layer before starting work, it must be moistened to avoid dusty environment, clogged filter and overheating of equipment.

When working with crushed stone, the characteristics of this material are taken into account. It is recommended to tamp solid granite and gravel rubble incrementally. First, the thinnest layer is poured, the thickness of subsequent layers is gradually increased.

Certain difficulties are presented by tamping of coarse-grained crushed limestone. To compact fractions more than 20 mm, it is recommended to use only heavy vibratory rammers. weighing from 140 kg. When using a lighter technique, the lower part of the backfill may remain unconsolidated. Aggregates weighing about 100 kg are suitable for fractions of 20 mm and less.

Scopes of vibratory rammers

This construction equipment is used to compact soil, sand, crushed stone, gravel, sand and crushed stone or sand and gravel mixtures. The scope of the tool depends on its mass. The larger it is, the thicker the layer, which can be compacted in one pass.

  • Lightweight models weighing up to 75 kg are effective for paving slabs and landscaping. Maximum thickness of the rammed layer. 150 mm.
  • Universal rammers weighing 75-90 kg are in demand when arranging foundations for foundations and floors, laying asphalt, partial repair of roads, construction of sports and playgrounds, car parks. Thickness of the compacted material. up to 250 mm.
  • Vibrating plates of medium weight have a mass of 90-140 kg and can be used for compaction of foundations under the foundation, backfilling of trenches in which engineering communications are laid, for strengthening embankments, for constructing road embankments. The rammed layer. up to 600 mm.
  • Heavy models weighing from 140 kg are used in the construction and repair of large-sized objects.

How to work with a vibratory plate?

Compaction of bulk materials. soil, sand, crushed stone, gravel. is an event that can be significantly accelerated by using a vibrating plate. This construction equipment can be electric, gasoline or diesel powered.

The technique is quite simple to operate, but it is necessary to familiarize yourself with the rules and recommendations of the manufacturer, how to use the vibratory plate correctly when ramming various materials.

How to work with a vibrating plate?

Before starting operation, the unit must be inspected for external damage, the reliability of fastening parts and mechanisms, the presence of a sufficient amount of fuel (for internal combustion engines) or voltage in the mains (for electric models). Before turning on, the vibratory rammer is placed on a flat surface.

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The procedure for starting up the equipment depends on the model. Low-cost units are equipped with a manual starter. a cord that must be pulled gently and smoothly. Modern models have a start button.

Basic rules for working with a vibratory rammer:

  • The operator must be behind the machine and must not bend over the operating equipment.
  • If a turn is required, the operator must quickly pass over the rammer by turning it around with one hand.
  • The duration of operation without interruption is indicated in the passport. Usually it is 40 minutes. The required technological break is 10-20 minutes. Exceeding the established period of continuous operation leads to equipment breakdowns and its rapid failure.
  • The operating mode of the unit depends on the thickness of the compacted layer and the characteristics of the bulk material. It is forbidden to make additional efforts to increase the intensity of compaction.

How to properly work with a vibrating plate when laying paving slabs?

For ramming the laid paving slabs, it is recommended to use rammers weighing 75-100 kg. The use of heavier devices may cause the paving stone to split or sink below the general level if laid on a sandy base.

When compacting tiles, experts advise using damping gaskets, the functions of which are performed by rubber or polyurethane mats. Rubber mats are cheaper but have a limited lifespan. Another disadvantage of these products is the appearance of black marks on the surface of the paving slabs, which are washed off after several rains. Polyurethane mats are more expensive, but more durable and do not leave dark marks.

Safety precautions when compaction of bulk materials and paving slabs with vibrating plates

Basic safety rules when working with vibrating plates:

  • The operator must wear protective clothing and headphones to operate the machine.
  • It is forbidden to leave the instrument in working mode unattended.
  • When compaction of an inclined surface, the movement is made from top to bottom.
  • It is prohibited to operate the unit in a fire and explosion hazardous area.
  • When overturning, the vibrating plate is first turned off and then returned to its original position.

Special care must be taken when activating rammers without soft start function.

Compaction of sand

It is necessary to remember about the peculiarities of work in this case: dust may rise, due to which the environment is polluted, and the air filter is clogged. To avoid this, prepare the work surface in advance: moisten the sand with water, so that it compresses better.

Sealing pavement area

If compaction of paving slabs is required, a damping plate or polyurethane mat must be used.

You can buy rubber mats, which have gained popularity due to their low cost, but they have a short service life. In addition, in this case, the passage leaves black marks on the tiles. Of course, they are washed off over time by rains, but you have to wait.

Polyurethane mats are more durable and durable, do not leave any marks on the surface.

Remember that the plate compactor must be lightweight. In the region of 70-90 kilograms. A product that is too heavy can damage the integrity of the paving slabs. Also watch the power level while working. An increased indicator will cause destruction of the product geometry.

Compaction of rubble and gravel

It all depends on what kind of material you are working with. In any case, the use of a vibrating plate gives results after four times the surface treatment. If you have already performed four approaches, but the compaction of rubble has not occurred, then this will not bring results in the future. In this case, it is necessary to pour in thinner layers.

When working with crushed stone, it is recommended to work incrementally, that is, gradually, each time increase the layer thickness.

How to work with a vibratory plate

It is important to know how to work with a vibratory plate. Thanks to the competent operation of the device, you can achieve the durability of the equipment, ensure safe working conditions and excellent work results.

Compaction of crushed limestone

Working with large crushed limestone is not as easy as it seems. Due to vibration effects, material particles are collected in a large layer that cannot be compacted. In this case, the lower layers remain unconsolidated. To prevent this from happening, you need to use plates weighing 150 kilograms or more. If the vibrating plate weighs 100 kilograms, it is better to use crushed stone with a fraction of up to 20 millimeters.

The main conditions and principles of working with a vibrating plate

One of the first questions from users: how to start a vibratory plate. The nature and order of actions depend on the type of mechanism. Most modern models are easy to start, just press the start button. There are also devices equipped with a manual starter. In this case, you need to pull the cord, do it smoothly, and then let the equipment warm up.

It is not difficult to use a vibrating plate. You just need to know the basic rules of its operation and observe them in practice:

  • You must always remember about safety! The user must sit behind the appliance. Do not lean over the stove.
  • If you need to unfold the device, follow the recommendations: use one hand for this, while quickly moving behind the vibrating plate.
  • You can work without interruptions for no longer than 40 minutes, after that you need to give yourself a rest and vibrating plate (10-20 minutes is enough).

Now you know how to work with this technique correctly. Let’s consider in more detail the conditions for using the vibrating plate when performing certain tasks.

Safety engineering

To ensure safe working conditions, you need to know how to use the vibratory plate correctly:

  • Before each stage of work, you need to check the equipment.
  • Check regularly that there is enough oil in the hydraulic system and the engine.
  • Monitor the fuel level in the engine and refuel if necessary.
  • It is important to check periodically for fuel or oil leaks.
  • Inspect the vibrating plate before work for the presence of all parts and the reliability of their installation, as well as for defects.
  • Switch off the engine immediately after work and during breaks.

You can ask other questions about vibrating plates to our consultants.

Making a manual rammer

There are many options for making a rammer with your own hands. Someone makes massive structures entirely of iron, but in this case, welding will be required. Others prefer to do with the materials at hand. Consider the best option for making a manual rammer for compaction of soil, sand and gravel.

Helpful! Some people use round logs, but with the help of such rammers it is impossible to fully compact the base in the corners.

You will also need to prepare:

  • Steel plate at least 2 mm thick.
  • A round stick about 450 mm long (it will act as a handle for the future rammer). To do this, you can use an unnecessary shovel handle.
  • Wood screws and wood glue.

Features of compaction of crushed stone

Any novice builder sincerely wonders why to ram an already strong stone. However, there are several important nuances to consider:

  • Since crushed stone is obtained by crushing, its particles are obtained in different sizes with free-form edges. Because of this, when laying the underlying layer, the particles of the material do not completely adhere to each other, forming a large number of air voids, the appearance of which, ultimately, leads to a decrease in the level of resistance to loads. If the fragments of crushed stone are tightly adjacent to each other, the volume of the material will decrease, but at the same time a stronger base is formed.
  • If crushed stone is laid on rocky ground, then compaction can be dispensed with. In this case, it is only necessary to level the gravel.
  • After compaction of gravel, the layer thickness can be from 50 to 250 mm, depending on the loads that will be placed on the base.

In addition, when processing crushed stone, it is recommended to split the base. To do this, you need to divide the gravel into fractions. First, the larger material is laid, which is compacted by hand. Then backfilling of finer material is carried out, which is also compacted. The final top coat should consist of the finest material, which must be carefully leveled and re-tamped.

Thanks to this, the finished base will have increased strength. If you make a similar manual compaction of sand, the effect will be even better.

How to tamp sand with a vibrating plate

The procedure for compacting sand with a vibrating plate is as follows:

  • The layer thickness should not exceed 60 cm;
  • The entire surface of the seal must be evenly wetted with water. Water is required so that excessive dust does not rise during operation, which has a detrimental effect on filters of construction equipment. At the same time, excess moisture should be avoided, only a moderate amount creates the desired cementitious effect;
  • It takes about 3-5 passes with a vibrating plate;
  • If the achieved degree of compaction suits its characteristics, then the next layer can be poured, etc.

Installing the handle

Having retreated 100 mm from the upper edge of the bar, it is necessary to outline the center of the future handle. To do this, you must first measure the diameter of the handle from the shovel. Let’s say it is 36 mm. To prevent the handle from dangling, you need to use a drill, the diameter of which will be several mm less than the diameter of the handle. In this case, it should be borne in mind that the outer part of the hole in the bar will be slightly larger than the inner diameter, therefore, during work, it is necessary to periodically insert the handle into the bar and check how tightly it sits.

If the handle does not fit into the hole, in no case should you try to hammer it with a hammer. Otherwise, the timber may crack and the manufacture of a rammer for earth, sand and gravel with your own hands will have to start over. It is much easier to trim the cutting to the required diameter a little.

After the hole is ready, you need to apply glue to its walls and install the handle. Excess adhesive can be removed with a cloth. In order for the handle to hold tightly, you need to fix it with a long screw, which must be screwed in from one side of the bar.

When the glue has gained strength, you can start using the rammer. It is best to store your homemade tool in a dry place, or you can pre-paint the workpiece to make it last longer. If necessary, the steel tip can be easily replaced with a new one.

We make blanks

We will prepare the structure according to the drawing shown below.

After preparing everything you need, saw off the ends of the timber at a right even angle, according to the size. After that, using a planer, align the plane of the lower end of the bar and remove the chamfers from the edges of the workpiece with a size of about 5 mm.

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In order not to get numerous splinters during work, it is recommended to sand and grind the surface of the bar.

How to lay tiles with a vibrating plate

Laying paving slabs using a vibrating plate is not much different from the usual compaction procedure. The only prerequisite is the presence of a special polyurethane or rubber mat fixed to the working body of the equipment. The mat is necessary in order to avoid unnecessary damage to the tiles. Polyurethane plates are preferable because they are more wear-resistant and do not leave black stripes on the surface of the pavement.

When building foundations for houses, garages, country paths and much more, great attention is paid to the substrate consisting of gravel and sand. To ensure that the concrete monolith is laid evenly and does not begin to move over time, it is important to carefully level the underlying layer. For these purposes, you can use specialized vibratory rammers or rolling equipment, but manual ramming will be much cheaper.

The principle of do-it-yourself processing is that with the help of a home-made tool, blows are applied to the surface, due to which sand and crushed stone are compacted. In this case, ramming is performed after laying each of these layers.

How to compact sand without a vibratory plate

And although each vibrating plate includes instructions for use in the delivery set, questions about the use of the tool arise quite regularly.

The working capabilities of the vibrating plate are directly related to its weight. The greater the weight of the equipment, the greater the layer of material it is able to compact, tamp.

Features of sand compaction

Do-it-yourself ramming of sand has some nuances that should be considered when creating a solid foundation for a concrete slab.

First of all, it is worth deciding on the type of sand that is best suited for these purposes. It is better to use gravelly material, but it is not recommended to fill up fine sand for compaction. The larger the grains, the more compressive strength the base will have, so that shrinkage of the future house or parking area can be avoided.

If you plan to build a monolithic structure, then it is best to give preference to river or quarry sand of the middle fraction. However, even in this case, groundwater will influence the underlying layer. Therefore, in order to prevent the process of erosion of the base, it is necessary to lay geotextiles at the bottom of the trench, and only after that fill the sand.

In addition, before filling the sand, it must be sieved, since the presence of impurities (especially clay) can affect its properties. Monitor the moisture level of the material, the ideal consistency will be if a small ball can be rolled out of the sand, which does not immediately crumble. Accordingly, the moisture level of the sand should be within 8-14%.

Accordingly, 50% of the successful laying of a gravel-sand bed depends on the material itself, the remaining 50% falls on the equipment. As mentioned earlier, specialized machines can be used for these purposes, but it is much cheaper to make a manual rammer yourself.

Static seal

Static sealing equipment uses only its own weight to act on the material to be sealed. To change the force of action on the surface, you must either change the mass or the contact area.

This type of equipment does not ensure the compaction of the material to a sufficient depth, since K. When it occurs, the effect of “spacing” between the particles of the upper layer of the material, which prevents the compaction of the underlying particles.

This type of equipment includes static rollers with smooth drums and rollers with pneumatic tires.

How to compact the sand? Overview of methods

THOSE. If you have walked the same section four times and the rubble is still loose, subsequent passes are almost useless. Need to work with smaller layers.

We recommend starting work on crushed stone with small layers, gradually increasing the layer, until the vibrating plate gives the required degree of compaction.

Compaction of crushed limestone. When compacting crushed limestone of large fractions, the effect of “clinking” often occurs, which consists in the fact that large stones of the upper layers under the influence of vibration seem to adhere to each other, forming a hard, not rammed layer. In this case, the lower layers remain not compacted.

It is possible to overcome clinking only by using powerful vibrating plates, weighing over 150 kg. If you buy a 100 kg vibratory plate, we do not recommend that you use crushed stone with a fraction of more than 10-20 mm.

Sealing paving slabs. When compacting paving slabs with a vibrating plate, it is imperative to use a damping plate for the working plate.

Rubber mats for a vibrating plate or polyurethane mats for a vibrating plate are used as a depressing plate. Rubber mats are cheaper, but have some very significant drawbacks. First, they are very short-lived, which negates the savings compared to polyurethane.

The second and most important thing is that after passing over the tiles, rubber leaves black marks, which are washed off then only by autumn rains for several months. Polyurethane mats are a traditionally used product for vibrating plates. They are very durable i.e. Almost eternal, and of course they do not leave any marks on the tiles.

To compact paving slabs, it is advisable to buy a vibrating plate with a weight of 75-90 kg and an impact force of no more than 15 kN. High impact powers can destroy the geometry of paving slabs.

Vibratory plates

Sand pillow under the foundation

A foundation cushion is a layer of sand, gravel or crushed stone poured in prior to starting construction of the foundation. Mainly oil-like is used for the belt type, especially if the foundation is being built on unstable ground. The most common, not the cheapest, is considered to be a sand pillow, since this common rumor material well softens the load of a building on the soil, and you will always find its deposits in almost any area.

Compaction of various types of soil

Depending on the material to be sealed, appropriate compaction methods and equipment are selected.

Choosing sand for a sand cushion

Not every sand is suitable for making a sand bed for a foundation. Particular attention should be paid to its quality if you use a manual tamping with your own hands. for these purposes, gravelly sand with a fairly coarse fraction is needed. By using fine sand, it is impossible to prevent strong shrinkage of the building after construction, and it can be very uneven.

The most suitable for construction is river sand, but if it is impossible to use it, clean open-pit sand is also suitable. In order that the service life of the sand cushion does not decrease as a result of its mixing with the soil and the action of ground water, it is advisable to lay a layer of geotextile on the bottom of the pit, the strips of which, if possible, should be sewn together. Such a simple and inexpensive technique will significantly increase the life of the building, and also eliminate its shrinkage even after many years of operation.

Materials used

A suitable material for homemade manual ramming is a square bar with a side of 100 or 150 mm. It will not be possible to work with a round log in the corners and will have to be compacted with a significant overlap of the previous impact site.

It is not at all necessary to take new lumber, a used block will do.

The main thing is that the wood is free of rot and splits. Choose a piece of timber that you can lift.

Sand ramming with vibrating plate technology

Any building, from a small private house to a large shopping center, is based on the foundation. The strength of the entire building and its service life depend on its quality. But it is not only the quality of the concrete used that matters, but also the exact observance of the entire technological process. For example, poorly executed tamping of sand for the foundation can lead to the fact that the erected building can shrink, accompanied by the formation of cracks, both in the foundation itself and in the walls of the building. This, in turn, can lead to an increase in heat loss and, as a result, an increase in heating and air conditioning costs for the entire building.

Influence of soil moisture on its compaction

Any soil is composed of three elements: solid particles, air and water. During compaction, almost all soils reach their maximum density with a certain optimal water content in them.

Thus, dry soil does not lend itself well to compaction, while wet soil becomes soft and easier to compact.

However, the higher the water in the soil, the lower its density. Maximum density is achieved with an optimal moisture content in the soil, which is usually an intermediate state between completely dry and completely wet.

To determine the optimum moisture content for the soil, laboratory analysis is used according to GOST 22733-2002 (Soils. Method for laboratory determination of maximum density).

The degree of compaction of clean sand and gravel (free of impurities) almost does not depend on the moisture content in them, and can be tamped as much as possible in dry and water-saturated state.

Correct thrombosis of sand with a vibrating plate

How easy is it to compact sand without tamping? Easily! But you need a lot of water! My experience. Message for subscribers.

Sand under the foundation is rammed manually using a hand-held vibrator or a homemade bar with handles, or with a special device. a vibrating plate, which significantly speeds up the process of erecting a sand cushion. The use of a particular ramming method depends on the size of the structure and the amount of work.

Device for compaction of sand under the foundation

The sand is laid and rammed in several layers, each layer having a thickness of at least twenty mm. And they pass to the filling of the next layer after the previous layer has been compacted tightly. In this case, you should constantly monitor the evenness of the base using the building level.

The most optimal choice for a foundation cushion is considered to be coarse gravelly sand. It is undesirable to use fine-grained material, since it has low resistance to compression, which can lead to significant shrinkage of the erected building. Often, ordinary river sand with medium fractions is used for backfilling.

To improve performance, sand can be mixed with gravel or crushed stone, or each type of these materials can be used separately for making a foundation bed.

Vibration seal

Vibration sealing equipment uses a combination of static and dynamic action. Vibration is created by rotating the eccentric weight. Vibration shocks are transmitted by material particles to each other, which leads to a decrease in friction between them and mutual motion. This, in turn, allows the particles to repackage in the most dense state. Compared to static compaction, the vibration compaction acts on the material much deeper. Initially, this method of compaction was used only for non-cohesive soils (sand, crushed stone, etc.), but over time, vibration equipment appeared for compaction of clay soils and asphalt.

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The effectiveness of vibration equipment is recognized all over the world, and at the moment this method of compaction is the dominant one in the market.

Which sand is best to use for a pillow

Gravelly sand is used to create the foundation cushion.

For the construction of a high-quality sand cushion, experts recommend using coarse gravel sand. At the same time, it is categorically not advised to use a thin and fine fraction, because such a material negatively affects the resistance to compression, and this fact in the future threatens with severe shrinkage of the entire structure. In order for a reliable monolithic slab to be installed in accordance with all the requirements, it is advisable to use clean river sand of the middle fraction.

As a last resort, you can use quarry sand. But in order for the sand layer to last for many years, not to be destroyed and washed by groundwater, before filling a trench or foundation pit, an insulating material should be laid. geotextile. Why is this needed? This precaution will effectively prevent sand and soil from mixing in the future.

Materials and tools used:

  • Pegs and rope;
  • Sand;
  • Insulating material. geotextile;
  • Level and tape measure;
  • Excavator for digging a hole or shovel for the manual method;
  • Dump truck for the delivery of sand;
  • Vibratory plate, hand vibrator or large round bar with handles.

Monolithic sand cushion and its purpose

When using a sand cushion, the costs are minimal, and the effect is quite good.

By creating a sand bed, the cost of building materials is significantly reduced. At the same time, private developers have an excellent opportunity to easily and simply replace low-quality soil in the base under the foundation and at the same time make a general and uniform rise in the level of the entire floor. Despite the small material costs and simplicity of technology, such a monolithic slab copes with all the tasks assigned to it.

Sand base pillow: its advantages

  • It becomes possible to create a high-quality base for the foundation according to the permissible load standards.
  • There is a guaranteed protection of the entire base of the structure from destructive destruction by groundwater.
  • There is an excellent opportunity to level the entire site under the foundation of the structure being built.
  • And most importantly, this is a relatively low-cost construction stage compared to its value for the entire structure.
  • When is a sand cushion needed under the foundation??

    It is far from always required to make such an arrangement under the foundation of the structure being erected. Therefore, experts recommend that it is imperative to carry out a detailed analysis of the soil on the site where the house will be built. And already on the basis of these data, decide: is such a plate required in a particular case? But most often a sand pillow is necessary to create a reliable and strong house, as well as to protect it from groundwater, flood waters, freezing and thawing of the soil.

    Conditions under which it is necessary to install such a layer:

    Heavily soil must be tamped with sand, because. It deforms during thawing and freezing.

  • If, according to the analyzes, the site where the house will be built is problem soil. In this case, it is more expedient to compact such soil with sand.
  • Be sure to ram the heaving soil with sand, since during freezing and thawing of the soil it is strongly deformed.
  • The sand layer is an intermediate link between the base soil and the foundation itself, due to which the settlement of the entire structure in the future is significantly reduced.
  • To make a flat basement area near a dug pit or trench, experts most often use sand, since a thin layer of sand gives an excellent opportunity to align the bottom of the pit or trench with a horizontal mowing line. At the same time, it is possible to eliminate all, even minor irregularities of any surface.

    Diagram of foundation parameters depending on the type of soil.

    A building material such as sand is able to actively resist the natural compression process. Therefore, it is necessary to replace the surface layers of the soil with sand in order to avoid settling of the entire structure, as well as to protect its walls and foundation from dampness and moisture during many years of operation.

    Sand cushion dimensions:

  • The thickness of the layer of the sand bed itself is determined based on certain conditions. Usually the pillow is laid in a layer of up to 20 cm, thanks to this, you can significantly save on the consumption of cement under the foundation.
  • As for its shape, it is better to lay a trapezoidal sand pillow, which should taper towards the bottom. The taper angle should be 30 °.
  • In this case, the created monolithic slab should not exceed the width of the foundation itself by more than 3 times in thickness.
  • Foundation pillow

    The base slab is: sand, crushed stone and concrete.

    When designing a structure, it is necessary to provide for, and when laying a house, installation work is carried out under the foundation, when a pillow is laid, which still needs to be carefully tamped. Why is it required to ram? Then, so that a monolithic, strong and even slab was created under the base of the structure, the purpose of which is to ensure as little shrinkage of the entire building as possible in the future for many years.

    The foundation slab is of the following types:

    • Sandy;
    • Crushed stone;
    • Concrete.

    Each of them has its advantages and disadvantages, but this does not mean that each of the listed types of pillows can be suitable for the construction of any house. As a result, each developer is recommended to conduct a certain analysis and find out the condition of the soil. Why you should follow these precautions?

    Before starting to build a foundation, it is necessary to examine the condition of the soil, the presence of groundwater, etc.

    In this case, when constructing a structure, it is recommended to take into account the peculiarities of the climate, the condition of the soil, the presence or absence of underwater waters, the general parameters and dimensions of the object, as well as various other factors. An improperly selected slab for the foundation, as well as a poorly installed one, can lead to irreparable consequences, this includes the destruction and subsidence of the entire base and the appearance of cracks on the walls of the house.

    Numerous private developers give preference to laying a cushion under a sand foundation, it is distinguished by its simplicity and low cost of building material. over, such a solid slab has one drawback: heavy bulky buildings cannot be erected on it. But in private construction, when planning ordinary houses, there is no need to comply with such strict conditions, and therefore such a pillow has been popular among developers for many years.

    Compaction of sand under the foundation

    When building any structure, specialists take into account everything, even the most insignificant stages, which during further construction can become an important link in such a long process. They can even influence the operation of the building in subsequent years. At the same time, experts quite often ask the following question: why do we need a foundation for a house and why should it devote so much time and effort?

    The foundation is the foundation of the whole house as a whole. Without it, a strong and reliable building will not work. Therefore, great attention should be paid to its construction.

    The basis of any capital structure is a reliable and strong foundation, which determines how durable and high-quality this building will be in the future.

    At the same time, a special pillow under the foundation, which is sometimes not given due attention, which is considered a gross mistake, is the capital basis of the entire structure to be installed.

    Sand pillow and its device under the foundation

    Strip foundation diagram on a sand cushion.

  • First of all, on the site, an appropriate marking of the foundation is made and its main parameters are determined. To do this, use a level, tape measure, pegs and rope.
  • According to the markings, a pit or trench is dug to a certain depth, this directly depends on the selected type of future foundation. A pit or trench is dug with an excavator or manually with a shovel.
  • The bottom of the pit or trench must be leveled and carefully tamped.
  • To create such a foundation slab, sand is poured into a foundation pit or trench in several layers, the width of each layer should be up to 20 cm thick.
  • Each poured layer must be well tamped and moistened, but not watered with abundant water. This is especially important in the summer, when the water evaporates faster. Continuously wetted sand will give maximum density to the entire sand layer.
  • To compact the sand, they use special equipment. a vibrating plate. or rent a hand vibrator. If the first two methods are unacceptable, then homemade devices can be successfully used. For example, take a large round bar, attach handles to it and roll each layer yourself.
  • The number of layers depends on the required thickness of the pillow itself. It is necessary to fill and tamp the sand until the desired thickness is formed. At the same time, one must not forget to ensure that each new vertical layer is as even as possible, and at the same time to carry out horizontal alignment. The strength and reliability of the entire structure directly depends on this. In heaving soils, with the threat of freezing of the foundation, which has a sand slab under it, the installation of special drainage is required. Only in this way the sand layer will not be flooded with water and will not lose its original properties.

    How to choose the right sand

    When choosing sand, the following factors must be considered:

  • Large clay in the sand reduces the strength of the concrete solution itself and negatively affects the adhesion of the material, and this is very important when arranging a sand cushion.
  • To create a high-quality concrete solution, medium-sized sand is used. To arrange a sand cushion under the foundation, coarse sand is used. It is this sand. with large granules. that is best tamped, and it fits well into dense layers.
  • If we talk about the degree of moisture content of the sand, then professionals check this quality in the following way: sand is considered ideal, from which it is impossible to make a lump.
  • Before using sand for concrete mortar or arranging a pillow, it is recommended to sift it so that different inclusions cannot adversely affect the quality of work.
  • The foundation pillow is the initial layer that forms a reliable and stable platform on which the foundation for the house will be installed. Such a device allows the entire structure to be provided with minimal shrinkage over many years of operation and protects against the negative effects of underwater waters and soil displacement. Most often, professionals use a sand pillow for tape or monolithic types of foundation.