Do-it-yourself wood concrete composition. Do-it-yourself arbolite blocks: making arbolite blocks yourself at home

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final grade

They belong to lightweight wall building materials. They are made from sawdust, wood, cement, water and other ingredients.

The main component is wood chips, which is chopped wood. Such blocks have a greater strength limit than foam blocks and gas blocks. Important Features The materials are: high crack resistance and impact resistance.

The initial stage of wood concrete production is the careful preparation of all necessary components, then follows the preparation of the base, its casting into molds for further production of blocks.

Preparing the base

The filler for blocks includes shavings and sawdust in a ratio of 1:2 or 1:1. they must be well dried, for this they are kept for 3-4 months outdoors, periodically turning over and treating with lime solution.

In the latter case, per 1 cu. meter of raw materials requires about 200 liters of 15% lime solution. It will contain wood components for 4 days, which need to be mixed 2-4 times a day.

On at this stage the main goal is to remove the sugar contained in sawdust. It can cause them to further rot.

You can buy ready-made wood chips, or you can make it yourself by building a wood chip cutter. The video will tell you what it is and how it works:

Required Components

After the sawdust is prepared, the following additives are added to it:

• Slaked lime;
• Calcium sulfate and aluminum;
• Portland cement 400 grade;
• Soluble liquid glass;
• Calcium chloride.

As a rule, the share of these components in wood concrete mixture does not exceed 4% by weight of cement. They give the final product resistance to rotting, provide high fire resistance and ductility.

Manufacturing technology

Arbolite blocks have an optimal size of 25 cm * 25 cm * 50 cm. They are convenient not only during the manufacturing process, but also during installation. The casting process is as follows: the blocks are filled with an arbolite mixture of three layers. Each approach is followed by thorough compaction wooden hammer, covered with tin.

The excess mass is struck using a ruler, and the shape is kept for a day at an air temperature of +18°C. After the time has passed, the blocks are removed from the molds by lightly tapping and laid out on a flat base to completely harden for 2 days and dry for a period of 10 days.

The photo shows the process of removing the wood concrete block from the machine after molding:

Equipment

To produce arbolite blocks Different equipment may be required depending on the volume of production and the raw materials used. The manufacturing process of this building material and its final result must meet a number of criteria: GOST 19222-84 and SN 549-82.

Most often, tree residues are used to produce wood concrete. coniferous species. Their grinding is carried out on a chipping machine (РРМ-5, DU-2 and others). A more thorough crushing process is carried out using crushers (DM-1) or hammer mills. On vibrating tables, pieces of earth and bark are separated from the crushed wood mixture.

It is recommended to prepare the wood concrete mixture using paddle mortar mixers or forced cyclic mixers. Transport ready mixture special forms can be accessed using cubes or concrete spreaders. And the lift of the conveyor itself should not exceed 15° up and 10° down at a speed of up to 1 m/s. The mixture should be dropped at a height of no more than one meter.

Compaction of structures can be done either with manual tampers or with a brick press (Rifey and others). If you need to make wood concrete blocks in small quantities, you can use a special mini-machine. If we're talking about On an industrial scale, they use entire lines for the production of wood concrete blocks, which include machines for making blocks, presses and mixers.

This is what the line for the production of wood concrete blocks looks like

The best curing process is achieved by using thermal chambers with heating elements, IR radiation, etc. They can control the required temperature and humidity level.

Block forms

Molds for the production of arbolite blocks can be of the following sizes: 20 cm*20 cm*50 cm or 30 cm*20 cm*50 cm. For the construction of structures from arbolite blocks, forms can also be produced in other sizes (for floors, ventilation systems etc.).

Molds for blocks can be purchased, or you can also make them yourself. To do this, you will need boards 2 cm thick, which are knocked down into the required shape. The interior is lined with plywood and topped with film or linoleum.

Scheme for making molds for arbolite blocks

How to make wood concrete blocks with your own hands

Equipment list:

• Detachable form and inserts for it;
• Falling and vibrating table;
• Mold lifting installation;
• Shock-shaking table;
• Mixture tray;
• Metal mold tray.

Having everything necessary equipment for the production of blocks, you can get 300-400 m3 of building material per month. In this case, the area for installing all equipment will require about 500 square meters. m and electricity costs are 10-40 kW/h.

The production of large blocks requires additional reinforcement. When the form is half filled with wood concrete mixture, a layer of concrete with reinforcement is poured on top, after which filling with wood concrete continues.

When making wood concrete blocks yourself organic matter it is necessary to fill it with water, and then with cement until it is homogeneous. This will require 3 parts cement, 3 parts sawdust or wood shavings and 4 parts water. The resulting mixture should be free-flowing and at the same time retain its shape when squeezed in your hand.

Before pouring, the inside of the mold is lubricated lime milk. After this, you can lay out the prepared mixture in layers with careful compaction. The surface of the block is leveled with a spatula and filled plaster mortar to a height of 2 cm.

Video about how to make wood concrete blocks with your own hands:

• The mixture can be compacted using wood covered with iron.
• The blocks that were kept under the film in a wet state for about 10 days have the greatest strength. In this case, the air temperature should not be lower than 15 degrees.
• You can prevent the blocks from drying out by periodically watering them with water.

It is enough to simply make this building material yourself. If all technologies are followed, the final product will be easy to manufacture, have high strength, fire safety and a long service life.

Arbolite is light and fairly strong blocks of sawdust and cement, which are used as building material, garages and agricultural buildings. The technology for their production was invented in Holland in the 30s of the 20th century (Durisol is the original name). In our country, this material spread after the 60s.

If you are guided by patented Dutch technology and domestic GOST, then it is possible to produce high-quality wood concrete blocks only in industrial conditions. However this feature does not stop those who want to save their money. For several years now, this inexpensive, lightweight and durable building material has been successfully reproduced at home. To make high-quality wood concrete with your own hands, you just need to take into account some nuances that significantly affect the final result.

Wood concrete components

The first important information needed to make usable sawdust blocks concerns their composition. The main material is wood chips. Where to get it and what it should be like is briefly described below. The second component is the binder. Its role is usually played by cement, and the grade is selected no lower than 400. Well, the third component– water or lime mortar.

In industrial conditions, in addition to the above components, various additives are also used that have a positive effect on the strength and other characteristics of wood concrete blocks. To make the material at home, it will be enough to stock up on lime.

In some cases, adding liquid glass is practiced. However, this is not necessary. This component makes the blocks more durable, but at the same time fragile.

Where to get wood chips for making wood concrete blocks

Usually the main raw materials are taken from large sawmills. It is also now possible to purchase a special machine for crushing wood. In this case, you must adhere to certain conditions. Firstly, the length of the chips should be predominantly 25 millimeters. It is at this size that the wood will serve not only as a filler, but also as a reinforcing base.

Secondly, it is advisable to sift out various types of debris from the chips - earth, bark, large and ungrinded pieces of wood. In production, this procedure is performed using special vibrating sieves. At home, if the wood chips are very dirty, you can wash them in water. This will also get rid of dusty sawdust.

How to neutralize sugar in wood

The cellulose present in the wood chips will negatively affect the quality of wood concrete blocks in the future. To get rid of sugar at home, there are two completely available methods. The simplest of them is to keep the wood chips under open air with periodic turning. This procedure usually takes at least 3 months.

To speed up the process of neutralizing the sugar contained in wood, you can use lime mortar. The wood chips are kept in it for several hours. Upon completion of the procedure, the solution is not drained, but serves to prepare the mixture immediately before forming the blocks.

Preparation of wood concrete mixture

According to the same Dutch technology, it is impossible to mix high-quality raw materials from wood chips and cement in a regular concrete mixer. It takes a lot of time to achieve a uniform consistency without lumps. In production they are used for this forced mixing machines. However, as experience shows, the wood concrete mixture can be prepared even manually with an ordinary shovel, and this does not significantly affect the quality.

The order of work should be approximately as follows. About 5–7 portions of wood chips soaked in lime mortar are placed in a concrete mixer. 3-4 portions of cement are also loaded there. If you plan to add any chemical components, then they are also added at this stage, taking into account the proportions. After loading, everything is thoroughly mixed.

You can check the correct preparation of the wood concrete mixture by touch. If it is slightly crumbly and holds its shape after being squeezed in a fist, then everything is done correctly.

Molding of arbolite blocks

How to produce without defects? There are two ways to do the job. If you buy a special molding machine, then no problems should arise. More budget option is the piece production of blocks. For this purpose they gather wooden boxes with removable bottom. The inside of the form is upholstered with linoleum or thick polyethylene. To make the loaded mass easier to remove after drying, the finish is pre-coated with a soap solution.

After loading the wood concrete mixture into the molds, the products are allowed to brew for 10 days at a temperature not lower than 15 °C. If the weather is colder, then the time should increase. At the same time, negative air temperatures are unacceptable.

In addition, to achieve maximum strength, it is recommended to cover sawdust concrete blocks with plastic film. This will make the hydration process more efficient.

More about production tools

Engage in production quality material impossible without:

1. Wood chip cutter. Also called a hammer crusher. Approximate price a new machine – 45-50 thousand rubles. The wood chip cutter produces wood chips that are easy to produce (length no more than 25 mm). It is for production in a subsidiary farm that it is enough to install a rotary-hammer type machine. Blueprints:
   
2. Machine for arbolite blocks. Again, the work will require a device not of an industrial scale, but a mini version of it. Since small-scale production of wood concrete is gaining momentum, the price of equipment for garages, sheds and small industrial areas is correspondingly increasing. The equipment will cost the private owner the same 50-60 thousand. One block can be produced in one minute, which gives up to 6.5 cubic meters of material per working day (approximately up to 450 blocks)
3. Concrete mixers. Gravity-type devices common in construction will not work. Their cycle is not enough for a high-quality mixture. Because even your own small-scale production requires a forced-type apparatus (mortar mixer). Usually they are also made with their own hands.
   
4. Press. For small volumes, it is possible to compact the mixture manually, but a private flow line requires a vibropress. The Rifey company has proven itself to be excellent.

   

   Rifey devices.

   

   But the most common device for a production line is “Condor 1”, costing from 265 thousand rubles.

However, private subsidiary farming accepts any auxiliary means, so it is also customary to use “Builder-1” or “Hephaestus-1” mini-machines.

1. Special forms. There is nothing complicated here; you can stamp ordinary boxes for convenience. But there are some tricks. For example, it is customary to cover internal areas with oilcloth. This is simply ideal for drying mortar. Sometimes oil waste is simply poured into the bottom of the mold. There are many innovations, but the most important thing is the process of compacting into the mold itself. It is impossible to arrange the composition evenly right away, so make 3 or 4 bookmarks with periodic tamping.

Do-it-yourself wood concrete from reeds

In fact, the composition of such material includes crushed wood and cement. Such a mass of mixture can harden under the influence of electrical force.

More popular this material called wood concrete. Its difference is that you can choose any tree species as sawdust. It is not forbidden to add even straw to the composition. In appearance, this wood concrete is similar to ordinary chipboard sheets:

Peculiarities:

• Low thermal conductivity;
• Excellent sound insulation;
• Fireproof material (fire does not spread throughout the blocks, but goes out in the inside);
• Lighter than brick or wood;
• With the proper composition, the strength coefficient is not inferior to foam concrete.

The production technology is simple and not complicated. How to do it right:

1. Wood and reeds must be chopped. There is a chipping machine for this.
2. Then the natural ingredients are simply soaked in water.
3. Next, the crushed mixture is placed in a forced-type mixer, where cement and additives are added. The latter are needed for better strength and speed of hardening.
4. Sometimes dyes are added.
5. The mixture is compacted into a steel form (formwork) manually.
6. Next comes the turn of electric current.
7. Voltage must be applied to a steel form (this is a kind of electrode).

Thus, it is possible to produce both blocks for sale and monolithic type partitions directly at the construction site.

The final stage of production on video

Narrated by VLADIMIR SHVYLEV.

– very unusual look concrete, where the main filler is waste from the forest processing industry - shavings, pine needles, etc. It is the composition that provides this building material. So, today let's talk about the composition for and blocks from it according to GOST, proportions, recipe and production technology.

Like any concrete, the material also includes a filler - only of organic origin, as well as various additives. The origin and properties of the ingredients influence the quality of the final product.

Organic fillers provide wood concrete with very significant heat and sound insulation properties. In terms of strength, the material is not much inferior to concrete with the same density indicators. This combination of qualities is only possible with making the right choice raw materials.

We’ll talk about how to make wood chips for the production of wood concrete with your own hands below.

This video will tell you more about how to choose a composition for wood concrete and sawdust concrete:

Organic Ingredients

Several types of material are used in the form of wood filler. Not every shaving is suitable as a raw material - the material should not be confused with sawdust concrete. The new GOST clearly regulates the size and geometry of fractions added to wood concrete.

• wood chips- it is obtained by crushing non-commercial wood - slabs, knots, tops and the like. To produce wood concrete, wood chips are used 15–20 mm long – not exceeding 40 mm, 10 mm wide and 2–3 mm thick. In industrial conditions, crushing is performed by special installations. Practical research suggests that to achieve best quality crushed wood chips for wood concrete should have a needle shape and be smaller in size: length up to 25 mm, width - 5–10 mm, thickness 3–5 mm. The fact is that wood absorbs moisture differently along and against the grain, and the above dimensions equalize this difference.

Not every tree is suitable for wood chips: you can use spruce, pine, aspen, birch, beech, but larch is undesirable. Wood material must be treated before use antiseptic compounds to prevent the development of mold or fungi.

• Shredded bark and needles can also be applied. However, their share is smaller: bark should be no more than 10% of the product’s weight, and pine needles should be no more than 5%.
• The raw material can be rice straw, flax and hemp, as well as cotton stems. The materials are crushed: length should not exceed 40 mm, width – 2–5 mm. Tow and tow, if they appear in the filler, do not exceed 5% of the mass. GOST 19222-84 regulates the sizes of fractions that are obtained by grinding one or another raw material. And although deviations in the proportion of ingredients are allowed, it is impossible to deviate from raw material standards.

Flax contains a large number of sugars, and the latter, reacting with cement, destroy it. Before burning, the flax is soaked in lime milk for 1–2 days, or kept in air for 3–4 months.

Inorganic components

The binders in wood concrete, which is what wood concrete is called, are the following substances:

• – traditional material and the most popular;
• Portland cement with additional mineral components - this usually increases the frost resistance of the blocks;
• sulfate-resistant cement, with the exception of pozzolanic cement, provides resistance to chemically aggressive substances.

According to GOST requirements, only material of the appropriate grade can be used:

• no less than 300 for heat-insulating wood concrete;
• no less than 400 for structural.

Now let’s talk about the proportions of chemical additives in the wood concrete composition.

Chemical additives

Total additional ingredients can reach 2–4% by weight of cement. Most of them increase the strength of wood concrete: the substances interact with the sugars present in wood and form compounds that are harmless to cement.

The specific amount of ingredients is determined by the brand of wood concrete. For example, grade 30 wood concrete may include:

• calcium chloride and aluminum sulfate in a 1:1 ratio - no more than 4% by weight of cement;
• calcium chloride and sodium sulfate in a 1:1 ratio - no more than 4%;
• aluminum chloride and aluminum sulfate in a 1:1 ratio - no more than 2%;
• calcium chloride and aluminum chloride in a 1:1 ratio - no more than 2%.

Sodium and potassium silicates can also be used for the same purposes.

Water

GOST regulates the degree of purity of water, but in practice any kind is used - central water supply, wells, boreholes. For the quality of wood concrete, the water temperature is fundamental. It is added to the composition along with additional ingredients.

In order for the rate of cement hydration to be sufficient, you need water with a temperature of at least +15 C. Already at +7–+8 C, the setting rate of cement drops noticeably.

Proportions

The composition of wood concrete is not strictly regulated. If the material meets the requirements of the specifications, then this indicator is considered more important than the accuracy of the composition. The approximate proportions are as follows: 1 part aggregate, 1 binder and 1.5 parts solution with chemical additives.

More precisely, the composition is calculated for a specific brand, where it is important to achieve the required strength and density.

For example, the ratio for ordinary wood concrete per 1 cubic meter. m.

If the wood filler is heterogeneous, then the proportion of wood chips and shavings in it is determined as a ratio of volumes, for example, 1 bucket of sawdust and 1 bucket of shavings. 1 bucket of sawdust and 2 shavings are also allowed.

• In a mixture with crushed grain, the proportions of wood chips and sawdust will be equal - 1:1:1.
• Flax and cotton stalks can replace sawdust in the same proportion.

This video will tell you how to mix the crossbow concrete mixture according to the specified proportions:

GOST

The composition of wood concrete is regulated by GOST 19222-84. The standard allows you to select the composition of the mixture according to laboratory conditions, but imposes strict requirements on raw materials and on the parameters of the final result. Depending on the compressive strength and thermal insulation performance, there are 2 types of wood concrete:

• thermal insulation, that is, designed for wall insulation;
• structural – self-construction is allowed load-bearing walls.

The indicators of these materials are different.

Since the operating conditions of wood concrete products can be very different, they may be subject to additional requirements regulated by GOST 4.212-80.

The grades of wood concrete are named according to GOST 25192-82. The structure of the material may also be indicated.

Dimensional deviations in products

GOST regulates possible dimensional deviations in products:

• in length, with a total block length of up to 3.0 m - no more than 5 mm;
• for product lengths from 3 to 6 m – 7 mm;
• deviations in height and thickness can only be within 5 mm;
• the error in the dimensions of protrusions, recesses, shelves, ribs, and so on does not exceed 5 mm.

It is allowed to reinforce wood concrete products with meshes and steel rods, regulated by the relevant GOST.

Since the material is not highly moisture resistant, the outer surface of the products is covered with a layer of decorative concrete or other material with mineral fillers. The inner layer may be missing. Finishing with cement or cement-lime mortar is allowed.

Checking the crossbow mixture

According to GOST, the crossbow mixture is checked at least 2 times per shift:

• estimate the density indicator;
• workability;
• level of delamination;
• assessment of intergranular voids.

To test for strength, a series of laboratory tests are carried out, for the mixture after 7 days of hardening, for the mixture after 28 days, and for the mixture that was tested both after 7 days and after 28.

• evaluated for finishing and load-bearing layers,
• Thermal conductivity is measured using samples of the mixture,
• Humidity is calculated on samples from finished products.

Only if the mixture passes the tests proposed by GOST can it be fully considered working and accepted for production.

Arbolit - example good combination organic filler and inorganic binder. And as with all types of concrete, the composition largely determines the quality of the final product.

You will learn how to select the composition of wood concrete and mix the ingredients for building a garage in the video below:

Arbolite, as a building material, was known back in the days of the USSR, factories were operating and houses were being built. After the collapse of the country, the technology was forgotten for some time, and a few years ago it was remembered again. The material is warm, light, durable, does not conduct sound well, and is also inexpensive. Therefore, wood concrete and wood concrete blocks (arbolite blocks) are increasingly of interest to private developers.

Let’s immediately determine that wood concrete and sawdust concrete are different materials With different characteristics. Wood concrete contains waste from the woodworking industry, but only in a strictly regulated size. There is no other filler anymore. Moreover, everything is prescribed in GOSTs and instructions. And the filler is not sawdust, but wood chips with dimensions recommended by the standard of no more than 40*10*5 mm.

Properties, advantages and disadvantages

For a private developer, when choosing a building material, the technical characteristics of the material are important. Let's look at wood concrete blocks from this side. So, the characteristics and their brief explanation:

The properties are very good. Another thing is that they will only be provided that the proportions and technology are strictly observed. This is why arblite blocks are dangerous: you don’t know how well they are made.

Performance characteristics

As you can see, the characteristics of the arboblock are quite good. Another plus is the low weight, big sizes and good ability to absorb sounds. A very big plus is that the blocks are easy to cut and can be easily given the desired shape. Another positive point— wood concrete holds nails and screws well. There are no problems on this side either.

• Shrinkage - 0.5-0.6%. This parameter shows how much the geometric dimensions walls under load. Wood concrete has one of the lowest rates.
• Water absorption 40-85%. This figure is very large. If you put an arbolite block in water, it can absorb a lot of water. For the developer, this means that care must be taken to ensure good waterproofing between the foundation and the first row of blocks. Also, an arbolite house needs exterior decoration which will protect the material from moisture. It's not all that scary. It is much more important that the hygroscopicity of wood concrete is low (the ability to accumulate vaporous moisture). Even with very humid air, it does not become damp, but allows vapor to pass through itself, regulating the humidity in the room.
• Fire resistance - class G1. Arbolite refers to materials that do not support combustion. This is their undoubted advantage.

If speak about technical specifications, then there is essentially one serious disadvantage - high water absorption. There is one more drawback, but it is from the field of operation. Mice love arbolite very much. The material is natural and warm. The problem can be solved by making a high base - no lower than 50 cm.

Technology for the production of arbolite blocks

Arbolite belongs to lightweight concrete, the technology is almost standard, with the exception of some nuances: the need for pressing and the use of a forced concrete mixer when mixing, not an ordinary gravity one. It mixes the wood chips better with the other ingredients.

Compound

The composition of wood concrete includes four components:

• high-quality cement (M 400 or M 500);
• wood chips;
• water;
• chemical additives.

The cement must be dry and fresh. Chips are of a certain size. The less misgrading there is, the stronger the block will be. Chemical additives are calcium nitrate and chloride (food additive E509), liquid glass, aluminum sulfate and some other substances. Please note that they are first diluted in water and only then added to the wood chips and mixed. Any drinking water is allowed, but not industrial water, without contamination. After the wood chips are evenly wet, cement is added. Any other sequence is not allowed.

Types and sizes of blocks

Depending on the density, wood concrete blocks are divided into thermal insulation (up to 500 kg/m 3) and structural (from 500 kg/m 3 to 850 kg/m 3). For construction one-story houses you can use the lightest structural ones with a density of 500 kg/m 3. For mansions of 1.5 and 2 floors, the minimum density is 600 kg/m3 and above.

The sizes of arbolite blocks can be different. The most common is 500*200 mm and different thicknesses - from 100 mm to 400-500 mm. But different factories and workshops produce blocks of different sizes. Molds for them can be welded from ordinary sheet iron, so that's not a problem. The photo shows an example of the assortment of one of the workshops.

As you can see, blocks of 600*200 mm and 600*250 mm are also available and thicknesses range from 100 to 500 mm. You can choose suitable ones for load-bearing walls and interior partitions. Also for self-made arbolite blocks can be made into a suitable shape. That is if you decide to make them yourself.

Proportions

Like any building material, wood concrete is divided into strength classes. For the construction of load-bearing walls of houses, the required strength class is B 2.5.

Quantity necessary materials per cubic meter of wood concrete mortar is in the table (photo above).

Pressing technologies

All these components are mixed and blocks are formed from them. There are several technologies:

• just by pressing:
  • manual on the floor (great effort required);
  • manual rammer on a vibrating table.
• pressing with vibration on a vibrating machine.

The easiest way to do this is by hand pressing. But it is difficult to control the density and strength of the resulting blocks in this way.

Normal production conditions

For the normal process of cement hydration, a temperature of at least +12°C is required. There are no other conditions. The peculiarity of production is that after molding the block, at least 2-3 weeks must pass before it can be used. During this time, the cement will gain about 50-60% strength (depending on temperature) and you can already work with the blocks. That is, blocks must be made long before construction begins. If you consider that the wood chips must sit for at least 4 months before they are used, then you can start a year before construction.

Another practical point: if you are going to make wood concrete blocks with your own hands, in addition to a platform for mixing and storing components, you need a platform for settling the blocks. The place should be covered, protected from rain and sun. There should be no drafts either.

Wood chips: how to get or where to buy

The best wood chips for wood concrete are made from pine and spruce. You can also use larch, but when mixing it is necessary to double the amount of chemical additives. Among hardwoods, GOST allows the use of aspen, beech, birch, and poplar. The remaining requirements are:

The best wood chips come from lump waste wood. It is first passed through chippers and then crushed in a hammer crusher. The following mechanisms can be used for this:

• Disc chippers with adjustable knives. Not all of them can be adjusted to produce chips of the required size, but the sizes will be close.
• Rotary knife crushers. They produce narrow and not wide chips, and the length is adjustable. That is, this is - a good option. There is only one “but”: there are a lot of knives and with prolonged use they need to be changed or welded (they do not sharpen). As an advantage, we add that crushers of this type can be used for re-crushing process chips obtained during the first crushing (after reconfiguration).
• Shredders or roller grinders. This is expensive equipment (about 1 million rubles), mostly imported, but it is excellent because it is manufactured for specific chip sizes.

If you do arbolite chips Doing it yourself is not an option; you can buy it. If possible, you can negotiate at the factory where wood concrete is produced. Just check the chip parameters. If there is none nearby, you can take chips from under the calibration machines. Some of them can be adjusted so that the chips are not thick.

Features of making mortar for arbolite blocks

Wood waste contains sugars. If you use fresh raw materials, the sugars may begin to ferment, which will cause the destruction of the integrity of the block. When mixing, chemical additives are added to the solution that neutralize their effects (liquid glass, calcium chloride, alumina sulfate, lime). They can be added in combinations: calcium chloride with liquid glass or alumina sulfate with lime. total weight additives should not exceed 8%.

There are other ways to break down sugars. The simplest, but requiring a long period of time, is to keep the wood chips in a pile for at least 90 days in the air. If it is not possible to wait, the wood chips are soaked in lime milk for 3 days, stirring occasionally. Then it is strained, not dried, and used in this form for kneading. Only in this case it is necessary to take into account that significantly less water will be required. This method works well, but it is very troublesome. It is easier to find an opportunity to purchase chemical additives.

The procedure and features of mixing the solution

To mix the solution, use a forced-type concrete mixer. You can also use a regular gravity or “pear”, but you have to knead in it for a long time, although you can adapt - tilt the pear as low as possible when kneading (it hardly mixes when raised).

First, sawdust is poured in and a certain amount of water is added. While the sawdust is getting wet, chemical additives are diluted in a small amount of water, then they are unloaded into a concrete mixer. When all the wood is uniformly wet, cement is poured. It is loaded in portions, waiting uniform distribution throughout the entire volume. The cement should envelop each chip from all sides. This is only possible if the sawdust is well wet, so we monitor this stage carefully.

Block molding

The solution is poured into molds. Most often they are made of metal and are a box with handles without a bottom. The form is placed on a flat surface (a board, for example). At manual tamping the molds are filled with wood concrete mortar, layer by layer, each of which is pressed with a metal platform with a handle. In order for the air to escape better, the thickness of the material is pierced several times. metal rod, after which they are pressed again. This procedure can be repeated several times until the desired layer density is reached, after which the next one can be poured. The layers are poured to the upper edge of the block, after final compaction the top is leveled, cutting off the excess with a metal strip.

You can use a lever - mechanical or driven. In this case, the force develops significant and the entire volume can be loaded at once, if necessary, adding to the edge. To achieve high density, you can press several times, now increasing and then weakening the pressure. Experience shows that with this principle of manufacturing arbolite blocks, they are more durable, and depressing (restoring shape due to the elastic force of the chips) is much less pronounced.

Better blocks in terms of strength and with less effort are obtained if vibration is added during the pressing process. In this case, the efforts required to obtain the required strength are reduced significantly. Vibrating tables are made for these purposes. And the process is called vibration with a weight.

The formed block on a stand is transferred to the drying place. If the solution allows and the block holds its shape, the frame can be removed. But sometimes homemade wood concrete blocks suffer from the fact that the solution turns out to be too liquid - this makes it easier to compact. In this case, the blocks are left in the mold for a day. Use and transportation of blocks is possible no earlier than 2-3 weeks after molding.

Features of the construction of their arbolite blocks

The blocks are laid according to the brick type - with bandaging of the seams, using cement-sand mortar. One of the features is the thickness of the seam - about 8-10 mm. Between the foundation and the first row of blocks it is necessary to make a very high-quality cut-off waterproofing. This will prevent moisture from leaking through the foundation from the soil. We do a combination of waterproofing - first we impregnate bitumen mastic or any other coating waterproofing, we lay it on top roll waterproofing. In the past, roofing felt was always used, but today it is of low quality and will collapse in a couple of years. And it is important to prevent moisture leakage (due to the high water absorption of wood concrete), so use waterproofing or something similar. It is possible, in two layers, also coated with bitumen mastic.

The next nuance is the masonry above the window and doorways. It is best to use special U-shaped blocks in which to lay a reinforcing frame and 4 reinforcement bars with a diameter of 10-12 mm. It is better to tie it down so that there is less chance of corrosion. First, blocks with recesses are installed above the opening. They can be supported from below with a board and spacers. Then the frame is laid, everything is filled with concrete. Leave the structure for a day, after which the supports can be removed and masonry can continue.

There are many nuances of building a house from wood concrete blocks in the video.

When it comes to reliable, economical and inexpensive building materials, wood concrete blocks are one of the first to come to mind. They make warm and comfortable houses. They are made from available cheap raw materials. In addition, wood concrete blocks can be made with your own hands without overpaying for finished industrial products.

Properties and scope of arbolite blocks

Arbolite blocks - wall material group of lightweight concrete used in low-rise (up to 3 floors) construction. Their standard size 200x300x500 mm. Most manufacturers offer a wider range of standard sizes. Residential buildings, low-rise commercial buildings, technical buildings, and outbuildings are used from arbolite blocks.

Residential buildings, commercial and commercial buildings are built from arbolite blocks. technical buildings, outbuildings

Wood concrete as a building material has a huge number of advantages:

With proper production and use of wood concrete blocks, you will achieve savings on several expense items at once: lightweight foundation, lack of additional thermal insulation, reduction in heating costs, minimum waste during construction.

The disadvantages of building materials include:

You can protect the building from attacks by mice and rats by pouring a high foundation (0.5 m above ground level) or by reinforcing the plaster with a metal mesh.

What is wood concrete made from?

To produce wood concrete blocks you will need the following components:

• wood chips;
• chemical additives;
• cement;
• water.

Size Requirements wood chips according to GOST - length up to 25 mm, width 5–10 mm, thickness 3–5 mm

You can take chips of a different size, shavings, sawdust. But remember that too large a fraction reduces the strength characteristics of the block, and a small fraction increases its thermal conductivity.

Experience shows that the most durable wood concrete block is obtained from an elongated needle-shaped filler.

Usually the raw material is pure pine and spruce wood, sometimes hardwood. Chips make up 80–90% of the total volume, which is why the material is often called wood concrete.

The wood concrete block consists of 80–90% wood, so it can be easily cut with a chainsaw

The wood is well dried - humidity no more than 23%. The inclusion of bark and wane up to 10% is allowed. The inclusion of leaves, pine needles, and straw is undesirable.

When selecting filler, proceed from the purpose of the future building. If you intend to build a residential building, the quality of the raw materials is of paramount importance. Wall material for outbuildings can be made from third-rate raw materials, including any plant waste. They just need to be crushed and dried well.

A chemical additive is necessary for the mineralization of wood chips - neutralization of sugars and resins contained in wood fibers. These natural substances prevent adhesion cement mortar with wood and impair its bonding. For mineralization the following are used:

• sodium sulfate (liquid glass).
• aluminum sulfate.
• aluminum chloride.
• calcium chloride.

Chemical additives can be used individually or in pairs in a 1:1 combination.

You can further improve the adhesion of chips and chips with 15% lime milk before drying them. Fill the raw materials with a solution at the rate of 200 liters of solution per 1 m³. Let stand for 4 days, stirring the mixture 3-4 times a day. Then spread the filler out in the open air and stir periodically. The drying process takes 3–4 months.

Cement should be taken only of grade M500, or, as a last resort, M400. It has maximum binding properties, hydrophobicity, and strength.

Calculation of raw material consumption

Calculate the required amount of wood concrete based on the total area of ​​the load-bearing walls minus the area of ​​the openings.

• If you intend to make standard blocks of 20x30x50 cm, then one block in the plane of the wall occupies 0.20 x 0.50 = 0.1 m².
• By dividing total area walls in m² per 0.1 m², you will get the number of wood concrete blocks in pieces.
• The amount of finished wall material is measured in cubic meters. The volume of one block is 0.03 m³.
• 1 m³ of wood concrete consists of 33 blocks.

To make 1 m³ of wood concrete you will need:

• 250–300 kg of Portland cement.
• 250–300 kg of dry filler.
• 400 liters of water.
• 8–10 kg of chemical additives.

Equipment and tools

There are machines for sale for making wood concrete blocks at home. They make labor-intensive work easier and faster, but are expensive. If you need wall material only for your home, and you are not afraid of the length of the process, you can do without expensive equipment.

You will need:

For the production of wood concrete, a forced-action concrete mixer is used

The form is made of steel sheet or wooden formwork. The metal mold consists of two parts. The box is made of steel with a cross-section of 1.0–1.5 mm. Its size is 30 x 50 cm, height 30 cm. The lid is made of steel with a cross-section of 3.0 mm and measures 33 x 53 cm. Apply clearly visible marks on the inner walls of the box at a height of 20.5 cm from the bottom. It’s even better to weld hooks about 5 mm high along the mark line, which will fix the lid to the given block thickness.

The mold for wood concrete blocks is made of steel with a cross section of 1.0–1.5 mm

Wooden formwork can be made from edged boards: a box with dimensions along the inner walls of 31 x 51 cm and a press lid 33 x 53 cm. The height of the box is 30 cm. The inner walls of the box and the bottom of the lid should be covered with linoleum so that the concrete mass does not stick to their surface.

Instructions for self-production

Preparation of raw materials

1. Sift the wood chips through a fine sieve to remove dust, sand, and small inclusions.
2. Pour 6 buckets of filler into the concrete mixer. Start the drum.
3. Dissolve 300–400 ml of chemical additive in 1 bucket of water.
4. Slowly pour water into the rotating drum. Wait a few minutes until the wood chips are evenly moistened with the solution.
5. Add 1 bucket of dry cement M500 to the drum in small portions. Bring the mixture to a homogeneous state.

Molding

• Pour the finished mixture into a trough or tray, from where it will be convenient to scoop it up with a shovel.
• Cover the tray on which you will form the blocks with film.
• Place the mold in the corner of the tray.
• Using a shovel, fill the mold to the brim and compact the mixture with a block. Its shrinkage will be about 30%. If necessary, add concrete.
• Place the lid in the mold, tap it evenly with a hammer until it drops to the internal height marks of the block.
• Carefully saving vertical position, remove the box from the block.

If you first place a weight of 2–3 kg in the middle of the lid, protect the raw block from damage by the unexpectedly lifted lid.

• Remove the cover.
• Place the mold box 15–20 cm from finished product and start shaping the next one.

To obtain the highest quality blocks, stripping should be done no earlier than 24 hours after molding the product. During this time, the strength of the block will reach 30%. In this case, it is better to make several dozen wooden formworks, which can be removed and used every 2-3 days. The blocks will reach 100% strength after 30 days of storage in a warm place, protected from precipitation and wind.

Video: DIY wood concrete block

To make wood concrete blocks, you do not need special knowledge or specialized skills. And if you don't mind the time it takes to create custom pieces, the wall material you make will be as good as the blocks that came off the assembly line.