Building blocks are a familiar material for the construction of structures for various purposes. They differ in size, constituent components, manufacturing method, but all are in demand wall structural material. Building blocks are made in industrial settings, concrete products and cinder blocks are also made in the household, which requires a do-it-yourself building block production plant. According to the material of manufacture, these products are divided into the following types:
- cinder concrete;
- concrete;
- Sawdust building blocks;
- aerated concrete;
- fiber foam concrete;
- polystyrene concrete.
Cinder blocks as a building material
Cinder block refers to standard concrete products, only instead of heavy gravel and crushed stone, aggregate in the form of spent slag is used. Such a replacement gives the material lightness compared to concrete and additional thermal insulation properties, since slag in terms of thermal conductivitycompares favorably with heavy and dense rubble.
The production of cinder blocks provides for the exact dosage of components in the solution, namely:
- cement brand not lower than 400 or 500, it is taken one part (bucket);
- quarry sand, mixed 3 parts (buckets);
- slag, burnt brick, expanded clay, this material is added in the amount of 5 parts (buckets);
- water.
To obtain cinder blocks of the same quality as in the factory, use a solution of medium viscous consistency. A liquid mortar will reduce the strength of the blocks, and a thick one will create uncontrollable voids inside when solidified.
Concrete blocks
Building blocks made of cement, sand and gravel are used for the construction of wall and other structures, if increased strength is required. The ratio of components for standard concrete is taken at a ratio of 1:3:6, other concrete mix options are described in the builder's manuals and depend on the cement grade used, aggregate size and type of sand.
Building sawdust blocks
For the construction of residential buildings, dachas, cottages, light and warm wall material is used from sawdust, sand and water. The binder in the solution is lime. The amount of material added to the solution changes the properties of the final product. An increase in the mass of sawdust leads to an increase in thermal insulation properties, but contributes to a decrease in strength. With an increase in the amount of sand in the solution, an increase in strength occurs, while the frost resistance limit increases, which increasesoperational properties of the material. Blocks are widely used in private housing construction as cladding for insulation of structures.
The main advantages of the blocks are the availability of materials and low price, long service life without destruction, environmental friendliness of the material, ease of production. A do-it-yourself building block plant is available to manufacture and is popular among home craftsmen. Sawdust concrete has an increased drying time, so several through holes are made inside the product to improve air flow.
The sizes of sawdust blocks are not strictly regulated, their width is taken as a multiple of the wall thickness. If we talk about standard sizes, then the blocks are made according to the double thickness of the brick (140 mm - 65x2 + 10 cm). In the manufacture of sawdust stones, dry ingredients are first mixed, then water is added, mortar mixers are used for work.
Aerated concrete building blocks
Their preparation involves a complex process of saturating the solution with gases, which is difficult to reproduce at home. Aerated concrete building blocks are distinguished by lightness, high soundproofing, heat-insulating properties.
Fiber concrete products for masonry
Fiber foam concrete is essentially an environmentally friendly wall material containing sand, foam and cement. High-tech building block machines spray foam into the mortar mass, it forms uniform closed particlesspace. To increase the strength of the blocks, manufacturers apply polyamide fiber reinforcement throughout the mass. This wall material is very durable, does not rot, is light and durable.
Blocks of their fiber foam concrete are produced in various sizes. For load-bearing walls, a block size of 20x30x60 cm is used, which weighs 22 kg. To build a brick wall of the same size, 18 stones will be required, they will weigh 72 kg. Blocks of smaller thickness (10 cm) are used in the construction of walls inside the building, partitions, they are used to insulate ceilings and walls. The thermal conductivity of fiber foam concrete is 2.7 times less than that of brick and 2 times less than that of cinder concrete and shell rock.
Large block sizes reduce the use of cement-sand mortar for masonry by 20 times compared to building a wall of small-sized stones. Fiber foam concrete does not burn, does not change shape when exposed to high temperatures and does not emit harmful impurities when heated.
Polystyrene concrete blocks
The material belongs to the next variety of lightweight wall concrete blocks. It differs from standard concrete in better performance and reduced production costs. The innovative wall material surpasses all known lightweight concretes in terms of weight, even foam concrete is one and a half times heavier than it. Thanks to this indicator, houses are built without the usual massive foundation, and the cost of transporting material is reduced.
The production of polystyrene foam blocks involves the careful mixing of cement, sand,expanded polystyrene particles and special additives to retain air in the total mass. All other physical characteristics of the material put it one step above the usual materials. Low water absorption and vapor permeability make expanded polystyrene concrete resistant to repeated freezing and thawing, which affects the durability of the structures being constructed. After the construction of walls from standard materials, a slight shrinkage occurs during the year. In the case of Styrofoam blocks, this time is not expected.
DIY building block machine
For the manufacture of building structures, a special device is used that works on the principle of a vibration processor.
Such a vibrating machine or a vibrating table is designed independently. A do-it-yourself installation for the production of building blocks significantly reduces the cost of the blocks, respectively, and the walls of the house.
Preparing the solution
The solution is prepared from sand, cement, water and aggregate, which are used as various materials, as described above. To check the consistency of the solution for fluidity, a small amount is thrown onto the ground. A high-quality mixture does not spread in watery streams; when squeezed in a fist, it sticks together into a lump.
The production of cinder blocks involves a thorough cleaning of slag from foreign debris, it is not allowed to get chips, unburned parts of coal into the solution. Sometimes gypsum is added to the solution. In this case, three parts of slag and one part of gypsum are mixed,water is added at the same time. This mortar is quickly used as the plaster hardens in minutes. Pre-slag before kneading is soaked with water. To improve the quality of products at the outlet, modern plasticizer additives are added to the solution. Their action increases the frost resistance, water resistance and mechanical strength of the blocks.
Depending on the purpose, two types of concrete blocks are made - solid and hollow. The former are used for the construction of solid structures, load-bearing walls, foundations. The second type of blocks is used as a partition material, it well isolates the building envelope from cold and extraneous sounds.
Production of concrete blocks without vibrating table
Of the two technologies, the use of a wooden mold, which is designed to spread the mortar naturally without vibration, is in ever-increasing demand. The placement of the solution in the prepared form is carried out in several stages. First, the container is filled with a third of the solution, after which the walls of the mold are carefully tapped around the perimeter with a hammer for high-quality shrinkage of the concrete solution. In the next two stages, the solution is poured according to the original technology until the mold is filled. The manufacture of building blocks with voids involves a technique when two plastic bottles of water are inserted into the uncured mortar, which, after setting, remove it.
Forms are left for 2-5 days to dry. Then the blocks are carefully removed from the collapsible structure and laid out on pallets until completely dry. Machine for cinder blocks with thisproduction method is not required to purchase.
Tools and fixtures you will need: a sieve for sifting sand, molds for mortar, a trough for kneading or a concrete mixer, a hammer for tapping, a bucket, a shovel, a trowel, drying trays.
Vibrating block making method
For this, a vibrating machine for cinder blocks is purchased or manufactured independently. A special form of metal is installed on the plane of the machine, and the concrete mixture with slag aggregate is poured into it by one third. After that, the vibrating table is connected to the action for up to 20 seconds, which allows you to remove all unnecessary air bubbles from the solution, and the cement will get good shrinkage. The solution is poured into the mold three times. Blocks are removed from the mold in the same way as in the non-vibration manufacturing method.
The cinder block does not tolerate overdrying in hot weather in the open rays of the sun, so on hot days it is sprinkled with water and covered with oilcloth or cellophane so that moisture does not evaporate so actively. Formed, completely dried concrete blocks gain 100% strength on the 28th day, and after that they are ready for use in construction.
Features of manufacturing cinder blocks
Forms are made independently, using metal or wood for this, boards take at least 190-200 mm in width. They are combined into a prefabricated structure, the side parts of which are detached to remove the finished block. The overall design combines notmore than 6 cells for laying concrete. The finished structure is installed on a dense waterproof material, such as oilcloth, which forms the bottom of the mold.
If wood is chosen as the material for the mold, then it is pre-treated with impregnations or primers to increase moisture resistance. Forms are made from dry wood. These conditions are met, otherwise, in the process of work, the tree will lead away from the water, and the geometric size of the block will change. The standard sizes of stones are 400x200x200 mm, but each private manufacturer makes blocks for his own construction.
For metal matrices, sheets with a thickness of no more than 3-4 mm are taken. When welding the structure, all welds are made from the outside so as not to round the corners of the block. The voids inside the cinder block are made using pieces of metal pipes of a suitable diameter, for example 80 mm. They control the distance between the pipes and the distance from the walls, the composition is welded with strips for rigidity and fixation.
If equipment for the production of building blocks is being made, then when attaching the vibrator to the table, after tightening the nuts, they are still lightly welded by welding. The motor must be closed with a protective casing made of any material from splashes of solution, water, dust.
Sawdust concrete block production technology
Available materials are not pre-processed, but you can buy them at any hardware store, so they start making blocks from sand, lime and sawdust immediately after purchase. To mix the solution, use a concrete mixer ormortar mixer, since manually mixing wood waste is difficult.
Dry sawdust, passed through a large sieve, mixed with sand and cement. Lime or cooked clay dough is added to the solution. The resulting mixture is well mixed and only after that water is added, gradually pouring it in small portions. To determine the readiness of the solution, it is squeezed in the hand, after which fingerprints should remain on the lump, which indicates the correct proportions.
Before filling the molds with mortar, they are lined with a thin layer of sawdust. Internal holes in the blocks are made using wooden plugs about 70-80 mm in size, which are installed in the matrix before pouring the mortar. The material of the building blocks is tightly packed into the mold using a special rammer. The container is filled to the top and left to dry for three days. After the end of this period, the solution gains about 40% of the prescribed strength.
The molds are dismantled, and the blocks are dried for another four days, after which the strength becomes 70% of the prescribed limit. Finished products are transferred to pallets and covered from direct sunlight. Drying of blocks is faster if gaps are left between the products during storage. It is advisable to place pallets in a draft or use a fan to force the airflow.
Sawdust concrete blocks gain 100% strength after drying for 3 months, but they can be used after a month of airing. At this time, their strength is 90%.
Machine and equipment
To do what needs to be donefor the construction of the number of blocks, they purchase a ready-made vibroforming machine. The TL-105 brand is distinguished by good performance. And although its power is only 0.55 kW, it produces about 150 concrete blocks with different aggregates per hour. Its approximate cost on the market is approximately 42,800 rubles. Modern machine tool manufacturers produce many varieties of block machines with additional features. Prices for machines are different, and the cost of building blocks directly depends on this.
For small private construction, a 1IKS vibrating machine is suitable, it costs about 17,000 rubles, its power is only 0.15 kW, it produces 30 blocks of such equipment per hour. When buying a machine, take into account the level of production of blocks for construction needs.
In conclusion, it should be noted that making building blocks with your own hands will save a lot of money on the production of products. The cost price does not take into account the wages paid to the employee. Overhead and production costs, taxes and other deductions are not added to the cost of the block, therefore, making the building material cheaper than a house.
