Making concrete blocks with your own hands. How to make money by making building blocks How to turn old concrete blocks into stone
One of the most common materials for construction load-bearing walls and partitions of residential buildings, as well as small industrial buildings are concrete blocks. Their popularity is due to their low cost, excellent performance characteristics and big amount varieties, which allows you to choose required block for almost any task.
The instructions given in this article will help you learn how to make concrete blocks yourself, and will also introduce you to their existing types.
Concrete blocks for walls
Types of artificial stones made of concrete
Let's look at the main types + characteristics of concrete building blocks, which are most common in modern construction.
cinder block
These wall stones are manufactured using the method of vibrocompression of concrete mortar on special platforms.
The composition of the mixture from which the cinder block is made may include:
- crushed stone for concrete products;
- brick fight;
- sawdust;
- expanded clay
Specifications Concrete blocks with slag leave much to be desired, but due to the fact that their price is one of the lowest on the market, cinder blocks are widely used in private construction.
But cost is almost the only advantage, since they lag far behind other materials in the following parameters:
- durability;
- heat-saving parameters;
- strength.
The main area of application for blocks is small buildings that will not be subject to heavy loads:
- sheds;
- garages;
- summer kitchens;
- workshops and so on.
Photo of cinder block
A less common material that is made from the following components:
- organic matter (mainly wood);
- binding element (powder);
- hardener.
Essentially, this artificial stone consists of sawdust enclosed in a concrete shell.
The advantages of the material are obvious:
- light weight of the concrete block;
- high thermal insulation properties;
- good sound insulation;
- efficient air exchange.
To protect blocks from negative impact environment, the stones are treated with a special solution. This prevents mold from forming and prevents rotting.
Wood concrete is perfect for construction small houses, which are suitable for year-round residence without the use of additional thermal insulation.
Arbolite block
Gas blocks and foam blocks
Cellular concrete blocks, according to GOST, which determines their technical characteristics, must consist of 70-85% artificially created pores (cells) filled with air. The most common are foam and gas blocks.
These materials have the following advantages:
- They are light in weight, as a result of which transportation of concrete blocks and their installation in private construction does not require the use of special equipment;
- easy to process - you can give the cellular block the required shape using an ordinary hacksaw for wood;
- walls made of cellular concrete blocks retain heat well and have excellent sound insulation properties.
Cellular concrete blocks are made from a solution containing sand, cement and aggregate. To form foam, lime, aluminum powder or another foaming agent are added.
Note!
Unlike foam concrete, aerated concrete is subjected to additional processing in an autoclave oven, where it is exposed to high temperature under high pressure (10-12 MPa).
As a result, this material acquires increased strength: it is almost impossible to crumble or break it.
Cellular concrete block
Self-production of blocks
Production technology artificial stone from cement mortar with filler is relatively simple, which allows you to make concrete blocks yourself.
Preparatory work
On initial stage the dimensions of the future block should be determined. When self-made the parameters of each individual element are taken based on the required wall width.
The thickness of the bottom of the block should not be less than 2 cm, and the walls of the voids should not be less than 4 cm. In this case, a standard stone measuring 20x20x40 cm with voids inside weighs about 40 kg, which makes it convenient for laying walls.
For production you will need any flat area covered with plastic film and special forms without a bottom.
The materials for the forms will be:
- boards;
- plywood.
To protect the wood from damage, the inside of the mold is lined sheet metal. Inserts are made in a similar way, thanks to which voids are formed in the finished block. They improve the thermal insulation properties of the material and make it lighter.
Molds for making concrete blocks
You can produce concrete blocks with your own hands faster if you make several forms in one block at once. To do this, you need plywood or a board with a width equal to the height of the future block. The material is sawn into pieces and fastened with self-tapping screws. Next, internal partitions are made.
Advice!
In order for the frozen block to be easily separated from the mold, all its parts must be lubricated with kerosene, machine oil or antifreeze.
Manufacturing process
To cast concrete blocks, you will need the following materials:
- fine gravel;
- cement;
- sand;
- water;
- lime;
- wire for reinforcement.
The quantity of each component is determined based on your needs for artificial stone. The proportions of cement, sand and gravel are taken in the ratio 1:3:5.
It is better to use a concrete mixer to mix the concrete solution.
For ease of presentation, we will divide the entire subsequent process into several stages.
Self-made concrete block
The technology described above allows you to make concrete blocks with your own hands without using much effort. Specifications finished products They will be practically in no way inferior to analogues sold in construction supermarkets, and the size will ideally match your needs. In addition, this can significantly reduce purchasing costs. building materials and their delivery.
The video in this article will help you get acquainted with the material in more detail.
Cinder block is one of the most popular materials today. It is used for construction projects for various purposes and the most different sizes. It may be small outbuildings or industrial buildings.
To make cinder blocks, a special device is used, the principle of which is to vibrate the concrete mixture. To significantly save on building materials, you can do building blocks with your own hands. To do this, you need to purchase or independently construct a vibratory pressing machine.
To start making concrete blocks with your own hands, you need to prepare all the tools and materials that may be needed in the process. Standard size cinder block is 390x188x190 mm. Interior the product remains hollow. Two or three holes act as voids, the shape and size of which directly depend on the configuration of the machine.
Thanks to such voids, the cinder block provides sufficient sound absorption and thermal insulation of the house. But, despite such a hollow structure, the material is very durable and will last for many years. Once you start making, you can significantly save on building materials.
Initially, concrete blocks were made from slag. In order to prepare a classic version of a cinder block, some proportions should be observed:
- 7 parts of coal slag from a blast furnace;
- 2 parts of expanded clay sand (it is better to give preference to the large fraction);
- 2 parts of gravel, the fraction must be no less than 5 and no more than 215 mm;
- 1.5 parts of cement grade 500;
- 3 parts water.
Other materials can be used as a filler; it’s just that in the classic version, slag was used. Today it is difficult to obtain, so brick waste, expanded clay, ash, gravel, screenings, crushed stone, gypsum or processed sawdust can be used instead. The amount of water may vary slightly depending on the filler. Its quantity must be adjusted during the preparation of the solution. The main thing is that it is not too dry, but spreading of the solution is also considered unacceptable.
In order to check the consistency of the solution, you need to throw a small amount on the ground. It is considered normal for the mixture to spread smoothly without water streaks, but if the mixture is squeezed into a fist, it should stick together.
If you make your own concrete blocks using slag, it is very important to ensure that there are no foreign objects. The slag must be cleaned of various chips and earth. It is unacceptable for the solution to include unburnt coal. In order to remove contamination, the material must be sifted through a sieve.
If gypsum is additionally added to the cinder block, the proportion of materials will be slightly changed. Gypsum (1 part) is mixed with three parts of the slag mixture, water is added during mixing. This solution must be used immediately after preparation, since the plaster will begin to dry quickly. It is recommended to soak the slag in water for some time before preparing such a solution.
The modern building materials market offers various additives that significantly improve the quality of the mortar. You can add a plasticizer to the solution; about 5 g is needed per cinder block. Such additives increase frost resistance, water resistance and strength.
There are two types of concrete blocks. They can be hollow or solid. The first ones are much lighter; they are used to build walls, since they do not create too much load on the foundation; in addition, such blocks have good sound and heat insulation. Solid blocks are most often used to build foundations.
In order to make a cinder block, you can use two technologies. One is based on the use of a wooden form in which to dry concrete mortar. For the second method, you need to purchase or make a special machine yourself.
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Manufacturing method using molds
Both wood and metal can be used as the material from which such forms are made. If wood is used to create the form, it must be very well dried. It should additionally be treated with a product that will increase moisture resistance. Otherwise, after a short time, the forms may become deformed, which will affect the geometry of the concrete blocks. Inner size the shape should be 400x200x200 mm. But this is not a limitation; the shape can have various sizes.
This form consists of a bottom and side walls. To make the production process faster, it is recommended to make several molds. In order for all corners of the mold to be filled well, the solution should be prepared more liquid. To make blocks hollow using a mold at home, you can use empty glass bottles.
After the solution is poured into the mold, the bottle neck is lowered into the mixture, the surface is leveled and the required height of the concrete block is made. After 5-6 hours, the bottles should be removed and the blocks should be left to dry further. Drying the blocks lasts at least a day, after which they can be removed from the molds and stacked. Before construction, such blocks must rest for at least 1 month.
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Concrete blocks using vibratory compacting machine
Using special equipment, concrete blocks are made more durable and of higher quality. Is it possible to manufacture vibration compacting machine with your own hands? Quite.
Tools needed to create special equipment:
- grinder for cutting sheets;
- welding machine;
- meter and chalk (pencil) for marking;
- pliers;
- hammer.
For the manufacture of matrices into which will be poured concrete mixture, you need to take sheet metal with a thickness of no more than 3 mm.
The machine must be equipped with a 100 W motor, in addition, a load should be prepared that will create imbalance and vibration.
- In order to make such a machine, it is necessary to use sheet steel. Blanks are cut from it:
- 2 pieces measuring 400x250 mm;
- 2 pieces measuring 200x250 mm;
- visor 400x150 mm;
- ribs – 4 pieces measuring 40x40 mm;
clamp size 39.5x19.5 mm. After all the blanks are made, you can begin assembling the main matrix. For this, parts measuring 400x200 mm and 200x250 mm are used. It is very important that all welds are on the outside. Otherwise, the finished concrete blocks will have rounded corners
. The result will be a matrix of 400x200x250 in size. To make voids inside a cinder block, you need to use a pipe with a diameter of 80 mm. The length of the workpieces should not be more than 250 mm.
TO final stage This includes the installation of a vibrator; it is attached to the longest side of the matrix. Bolts are used to secure it. Once the bolts are tightened, they are welded in place for added strength. To protect the motor from water and pollution mortar, a protective visor is welded on top. A leg is welded to the edge of the visor, which will add additional strength. For convenience, handles are welded to the matrices.
The optimal size for blocks is 20x20x20 cm or 20x20x40 cm. Thanks to their small dimensions, the process of laying the material, as well as the manufacturing itself, becomes convenient and simple.
It should also be taken into account that for special types of work it may be necessary to make half blocks.
To make concrete blocks with voids, a special mold is needed. Concrete blocks should be made on compacted soil or on a level area (for example, built from boards). The surface must be covered with oilcloth or thick film. The molds in which the blocks are formed are made without a bottom. They are made from boards, chipboard or plywood sheets, and covered with sheet metal on top. Several liners are made from wooden logs, with the help of which voids will be formed in the blocks, due to which the building material will become lighter and warmer. The edges of the logs are sheathed with metal and handles are mounted to them, which will help in the further process without extra effort
pull out the liners from the setting cinder block.
Experts say that it is most convenient to make several forms at the same time. To build them, you need to knock down or fasten with screws a frame with the height of the sides equal to the height of the block, in the middle of which plywood partitions are inserted. By the way, you should first install the longitudinal partitions, and then put the transverse partitions on them.
All elements and parts of the formwork must be coated with drying oil or machine oil, as a result of which the hardened blocks will be much easier to remove from the mold.
Laying the concrete mixture
- cement;
- Necessary materials:
- sand;
- lime;
- water;
- fine gravel;
rigid reinforcing wire.
The size of gravel grains can reach 1 cm.
The blocks are made of concrete based on a mixture of gravel and sand. Fine gravel, sand, lime (in small portions), and cement are poured into a metal basin. Mix the constituent elements thoroughly and then add water. There should be just enough water so that no problems arise during the process of laying the formwork (the mass should not be liquid).
The strength grade of such a material will be approximately 135 kgf/sq.cm. The size of the filler grains can reach 1 cm. Insert cores to form voids are placed in the mold when a solution 2 cm thick has already been poured and compacted. To fix the distance of the core, it is recommended to install special slats, about 4 cm wide, between the mold wall and the core. These slats can only be removed once the concrete has been loaded and compacted to one-third the height of the form.
The bottom of the form can be covered with old newspapers, which will prevent the block from setting to the previous base. The mixture should be semi-dry during installation. That is, when taken in a fist, compressed into a ball and then placed on a flat surface (for example, on a board), the mass should not spread.
Each formwork compartment is filled with a maximum of half of the solution, after which rigid reinforcing wire is laid.
To prepare the solution at home, you can use a stationary concrete mixer.
Some craftsmen make blocks using glass bottles as heat-insulating cinder block air chambers. To do this, plug the bottles with corks and install them in the middle of the block. After this, the forms are filled to the top, the solution is compacted and then smoothed with a trowel.
Freeze homemade blocks quite quickly - within 3-4 days, after which they can be safely removed from the formwork. However, this does not mean that they are completely dry. They can be used in construction no earlier than two weeks later.
Evgeniy Stepanovich, Perm asks a question:
Hello! I bought a plot on which I plan to build a house. After looking at how much a brick cost, I just gasped and decided that I would make the blocks myself. Even if I purchase all the components for building walls and a concrete mixer, I will spend less funds than buying bricks. True, I have never been involved in making blocks, although I have general idea about how to make them. Please tell us how. What proportions of components must be observed during their manufacture? What dimensions should the blocks be? How can you make a mold for casting them? Thanks in advance for the advice.
The expert answers:
Hello! Owners of suburban areas who decide to build a house on their own are often interested in how to make concrete blocks with their own hands. Their choice in favor of this building material is easy to understand. Although it is difficult to produce the number of blocks required for construction, in material terms, amateur builders find themselves in a significant gain. It must be said that the construction of the walls of a house with blocks will be much faster, since they are much larger in size than bricks.
You can determine the dimensions of the blocks yourself, but it will be difficult for you to lay out products that are too large. But it is impractical to produce building materials the size of a brick yourself. Optimal sizes products are shown in Fig. 1. From the same diagram you can see how the most simple form for its casting. The box is assembled from steel 2.5-3 mm thick. It has no bottom. When pouring, the mold is placed on a flat surface and filled with solution. To concrete block was without cavities that reduce its strength, the solution is compacted special device. Once compacted, the mold can be lifted and placed side by side to make the next block.
It must be said that a solid product will weigh a lot, so it is better to make it hollow. Such a block will be both less heavy and warmer (Fig. 2). To make it, the mold must be equipped with voids made from pipes plugged at both ends. Vertical plates are welded between the pipes in the upper part. In the same way, the voids are connected to the ends of the form. To make it easier to remove the mold after making the block, the seams at the ends of the pipes need to be processed, slightly rounding them. It is no longer possible to compact products in a mold with voids using a manual tamper. You can make the block stronger using a clamping cover and a hammer drill, which, after turning on in jackhammer mode, should be rested against it. The lid should fit freely into the mold. To prevent it from falling through, limiting corners are welded along its edges.
A more productive device for casting blocks is obtained if an electric motor is connected to it (Fig. 3).
In this capacity, you can even use the engine from washing machine. The motor is attached to the corners welded on one of the outer walls of the mold. For it to work as a vibrator, an eccentric must be attached to the shaft. Once the motor is turned on, it will cause the entire structure to vibrate. When pouring a block, it is better to place the mold on thick rubber, like a conveyor rubber. Rubber shock absorbers need to be secured to the bottom of the mold. When compacting, the concrete is covered with a clamping lid.
Blocks can be prepared from various materials. Suitable for this:
- coal slag;
- expanded clay;
- Sand and gravel;
- crushed stone screening;
- crushed bricks, etc.
Coal slag makes the blocks noticeably lighter. The filling solution is prepared:
Concrete blocks are often used for private and commercial construction. The most popular variety of this artificial stone is aerated concrete, or in other words, autoclaved porous concrete. It has unsurpassed energy-saving and heat-insulating properties, is lightweight and easy to process. In addition, you can easily make it yourself.
The technology for manufacturing aerated concrete blocks for individual needs and on an industrial scale will be the topic of today’s article.
Preparatory stage
Materials for production
The use of aerated concrete blocks in construction has many advantages.
Let's list the main ones:
- one 30-kilogram block can replace about 30 bricks at the same time, which affects the construction time of the building;
- the low weight of porous concrete allows the construction of private housing without the use of cranes and other special equipment;
- autoclave gas blocks can be easily processed using ordinary metalworking tools.
The simplicity of the production process makes it possible to produce required amount this building stone directly to construction site or next to her.
All you need is instructions describing the entire process and raw materials:
- water;
- cement;
- lime;
- quartz sand.
Note!
To obtain the porous structure of aerated concrete, a suspension of aluminum powder is used.
This active substance which may cause harm to human health.
Remember to use safety equipment.
Devices and mechanisms
Not so long ago, the complexity of technology did not allow the production of various concrete blocks at home, without the use of specialized production lines. Currently, the situation has changed dramatically. There is equipment for: for the production of aerated concrete blocks, for cinder blocks, for bricks and so on.
In the case when aerated concrete is produced not for one’s own needs, but for the purpose of subsequent sale, it makes sense to pay attention to other equipment:
- semi-automatic production lines producing 2-4 cubic meters finished products per day - good for individual entrepreneurship or medium-sized enterprises;
- automatic production complexes that allow the production of up to 100 cubic meters of aerated concrete blocks in 24 hours - suitable for a large enterprise engaged in the production of building materials.
Manufacturing process
Main part of the technological process
The production of aerated concrete blocks begins with mixing the raw materials. Considering that this building material has a porous structure and low weight, a fairly large number of finished elements are obtained from a small volume of sand, cement and lime.
For ease of presentation, we will divide the further process into several stages:
- Lime, water, cement and quartz sand are poured into a concrete mixer, where they are thoroughly mixed. After 5-10 minutes, a small amount of aluminum powder dissolved in water is added. This substance, having entered into a chemical reaction with lime, promotes the release of hydrogen. It is this gas that forms pores in the block ranging in size from 1 to 2 mm, which occupy the entire volume of aerated concrete.
- Immediately after adding the aluminum suspension, the mixture is poured into special molds, where it swells, increasing in volume several times.
- In order for the pores to be evenly distributed and the aerated concrete to harden faster, the forms are placed on a special table or platform, where the future aerated concrete is subjected to prolonged vibration loads.
- At the last stage, with the help of metal strings, irregularities are cut off from the top edge of the finished products, and the blocks are calibrated to the required size.
Advice!
In order to quickly cut and calibrate aerated concrete, you can use special milling machines.
Autoclave processing
Equipment for the production of aerated concrete blocks also includes autoclave chambers. In them, hardened workpieces are subjected to 12-hour steam treatment at a temperature of 190 degrees Celsius and a pressure of 12 kgf/sq. cm.
After this procedure, aerated concrete acquires greater strength and a uniform structure, and also exhibits minimal shrinkage after completion of construction.
It can be used as:
- heat insulator;
- sound insulator;
- material for load-bearing walls.
By the way, the excellent energy-saving qualities of aerated concrete, which has an excellent thermal conductivity coefficient, allows you to build houses from blocks up to 400 mm thick without using additional materials, retaining heat ( mineral wool, polypropylene foam, polystyrene foam).
Non-autoclave method
When producing aerated concrete, it does not have to be autoclaved. But such material will be less durable and have worse characteristics.
Properties of finished products
The aerated concrete obtained by the method described above has the following properties:
- low density (comparable to the density of solid pine) - it is 5 times less than that of monolithic concrete and 3 times - for brick;
- compressive strength, which allows the construction of 2 and 3 storey buildings from aerated concrete;
- moisture absorption, which does not exceed 20%, which is comparable to the same brick;
- frost resistance 2 times greater than that of brick;
- high thermal conductivity - 2 times less than that of pine, 15 times less than that of concrete;
- excellent sound insulation properties - with a wall thickness of 300 mm, it completely insulates sound with a power of 60 dB;
- withstands exposure to an open flame at a temperature of 900 degrees Celsius for 4 hours;
- aerated concrete can be easily cut with a regular hacksaw;
- the costs of its purchase or production are lower than those of similar materials.
Conclusion
The video in this article will help you learn more about the production technology of various building materials.
