Aerated concrete - a synthetic building material, which is a kind of cellular concrete, its weight does not exceed 0.5-1.2 t / m3 (against the weight of masonry 2-2.5 t / m3), then there is a light, porous material made on the basis of mineral.The entire volume of gas-concrete products uniformly distributed small round pores to 3 mm in diameter, and are due to a reduction in weight of the material.This article will talk about the installation of the walls of concrete blocks.
- production technology
- aerated concrete blocks Advantages
- Specifications concrete blocks
- Construction of houses of concrete blocks
- calculation of concrete blocks
- foundation for the house of concrete blocks
- Tools for installation of concrete blocks
- Laying of concrete blocks
- adhesive for laying concrete blocks
- Interior and exterior designs of aerated concrete
Aerated concrete blocks are widely used in construction throughout the world, the
aerated concrete production technology
The composition of the mass for the manufacture of aerated concrete are some mandatory and some additional components that can not be added, depending on the production technology.
- quartz sand;
- strongly alkaline cement;
- blowing (paste or slurry of fine metallic aluminum).
- metallurgical slag;
components dry thoroughly mixed together and then kneaded with addition of water.The resulting mass is spread in a metal-plastic molds without filling them to the brim.Foaming is a result of the interaction in the aqueous medium and the blowing agent of cement.After a short time, the mixture increases in volume and solidifies, whereupon the monolithic slab is removed from the mold and cut into rectangular blocks of the desired size.
- At the last stage of production, procurement dried in an autoclave (the device handle allows the material under pressure and at high temperature) or in drying chambers with electric heating.That technology finishing aerated divided into autoclave and non-autoclave.For most types of construction works recommended autoclave aerated concrete, which has improved technical specifications.Due to the steam treatment the product structure becomes greater uniformity and durability.
- non-autoclaved aerated concrete blocks are generally produced in small plants with a hand-made, since this technology does not require special equipment, and the mixture solidifies in the mold naturally.The finished material has lower strength and is recommended for buildings laying it in two rows, or the use of such products with an additional layer in the multilayer masonry.
Advantages of concrete blocks
blocks of aerated concrete have many positive qualities:
- a material with improved sound insulation and thermal protection;
- made based only on mineral components;
- has a high frost resistance;
- has a low specific weight - weight of the standard block size 62,5h10h25 see, does not exceed 10 kg;
- has good fire resistance, can withstand an open flame for 3-4 hours;
- rot in wet environments;
- characterized by quick and easy installation, easy processing, sawed and cut without special tools, making the price for the installation of concrete blocks lower than in the brickwork;
- economical material due to the low cost of the unit itself and less cost in the production of cement as well as by reducing the costs of transportation and installation of foundations, moreover, mounting blocks can be performed by one person, without the involvement of assistants;
- after the time finished masonry of aerated concrete is gaining even greater strength;
- has a low natural radioactivity;
- environmentally friendly material;
- at the low-rise buildings (up to 3 storeys), allowed to use the blocks for the construction of load-bearing structures;
- reinforced aerated concrete products can be used as floor slabs.
Of course, like any other material, concrete has its drawbacks.The main negative qualities include the presence of open pores, because of which blocks require additional waterproofing and such pores reduce mechanical strength.
Specifications concrete blocks
aerated concrete products are divided into two main types.
- Partition aerated concrete blocks - thickness varies from 7.5 cm to 20 cm, the main purpose: the device interior partitions and internal walls (non-structural), can also be used as a warming layer masonry.
- Wall aerated concrete blocks - thickness of 25 cm, the main purpose: the construction of load-bearing walls.For the construction of buildings in cold climates we recommend the use of aerated concrete products with a thickness of 37 cm in this case is sufficient for warming of plastering the outside of the building.
Aerated concrete products have the following options :
- density: 350-1700 kg / m3 (marked «D», the lower the grade, the warmer the material);
- density compression: 1-7,5 MPa;
- length: 60 cm, 62.5 cm;
- width: 7.5 - 50 cm;
- height: 20 cm, 25 cm;
- frost resistance: up to 75 cycles (marked «F»);
- environmental factor: 2.0;
- water absorption: less than 20%;
- thermal conductivity: 0,16-0,81 W / m3;
- drying shrinkage: 0,5 mm / m.
Construction of houses of concrete blocks
calculation of concrete blocks
- Before starting construction, should calculate the required material.As an example, take the house, which measures 15h13 m, at a height of 3 m. To calculate the area perimeter walls must be added to all four walls of the width and height multiplied by (15 + 15 + 13 + 13) x3 = 168 m2.
- If several walls have the same dimensions (as in our example), you can proceed as follows: + 15h2h3 13h2h3 = 168 m2.
- To find out how many cubic meters of concrete blocks need the result to be multiplied by the thickness of one unit (eg 0.3 m): 168h0,3 = 50.4 m3.This is the number of blocks necessary for the construction of the external walls of the building (units sold in pallet and measured in m3).The same pattern is calculated interior walls and partitions.
- If you want to calculate the number of single-piece products 1 m3 should be used to calculate the volume of a single unit, this multiplied the length of its sides.An example is a product with a standard size: length 60 cm, height 20 cm and 30 cm thick. First of all, it is necessary to translate centimeters or millimeters to meters.As a result, the following formula and the result: 0,2h0,3h0,6 = 0.036 m3.Next will be divided at 1 cubic meter volume of units produced: 1 / 0.036 = 27.7.It turns out that for the erection of one cubic meter of masonry must be purchased 28 units installed size, and for the house of 168 m2 will need about 1400 units.
Based on the calculations, you can calculate the approximate cost of the entire construction.
foundation for the house of concrete blocks
calculate the required amount of material, you can start the construction of the foundation.For the construction of aerated concrete is used several kinds of foundations:
- tape monolithic;
- monolithic slab.
specific form is chosen based on a number of parameters, such as the design of the house, the characteristic of the soil, the depth of the groundwater table, and so on. D.
Tip: experts recommend covering monolithic strip foundations.If the solution is not added to the foundation material for rapid solidification, it would take a month to leave the foundations for the complete hardening and curing.
Whatever the chosen base for the house, it should be thoroughly warmed and waterproofed.This can be done with the help of 1-2 layers of web material such as roofing material.Reason for masonry walls to be aligned in the horizontal plane.
Tools for installation of concrete blocks
before laying concrete blocks, it is necessary to prepare the necessary tools and materials for:
- aerated concrete blocks;
- adhesive solution;
- notched trowel and straight;
- building level;
- planer or sanding boards
- hand hacksaw or electric band saw;
To prevent cold bridges, which are formed in the cement-sand mortar, when laying the blocks uses a special adhesive compound based on Portland cement, silica sand and additives (mineral, polymer).Shuts mixture of clean water at a temperature less than 30 degrees.
Do not break the rules specified in the addition of water, as too liquid glue will have a reduced strength characteristics.Apply the adhesive layer is recommended not exceeding 3 mm, with a notched trowel.The prepared solution can not be stored for a long time, and you can adjust the location of the blocks for 3-4 minutes.
Company «Xella» for several years produces various instruments, the main purpose of which is to increase the quality and speed of execution of works on assembly of aerated concrete.Professional tool developed taking into account the technical characteristics of individual blocks are taken into account their size and geometry.
basic set of specialized support tool:
- trowel - the width of the width of the block is smooth, provides a layer thickness of 1 to 3 mm, the advantage is that when applying the solution does not drip on the sides, and accurately over the surfaceunit, whereby masonry remains free;
- carriage with dosing - also in size to the width of the blocks and is used for the fastest possible application of the adhesive mixture has a maximum width of 500 mm;
- mallet - rubber hammer to prevent damage to the cellular concrete (do not replace the product is a simple metal or wooden mallet, since their use leads to damage of aerated concrete blocks);
- wall chaser - helping hand cut grooves in the aerated concrete;
- hand saw or a chisel - used for accurate sawing blocks are tipped;
- plane - it helps to change the shape of the block and align the large irregularities in the masonry;
- sanding board - eliminate small irregularities and defects in the construction of gas-concrete constructions;
- Area - captures the block and helps to make it smooth cuts.
Besides specialized tool German company «Xella» manufactures aerated concrete blocks themselves «Ytong», as well as adhesives and winter mix.
laying concrete blocks
- Because how well laid the first row, depends on the strength of the entire structure.Laying of concrete blocks is different from the brick, since aerated relatively lightweight material that the installation is not squeezed out the excess solution from the joints.In addition, the walls of it can be built without technological pauses.
- To build external walls construction norms recommended for units with a thickness of not less than 37-40 cm, for external walls thick enough blocks of 25 cm, decorative walls and partitions may be built from aerated concrete thickness of 10 cm.
- So firstwe proceed to the construction of the first row of masonry, you should carefully prepare the ground.First of all it concerns the installation of waterproofing materials.As a waterproofing can be applied any roll bituminous or polymeric material (for example, roofing material) or a special waterproofing solution to polymer-based components.
- waterproofing material is applied on top of a layer of cement mortar 2-3 cm (approximate composition: 1 part cement, three parts sand) to help compensate for uneven foundation.Horizontal necessarily checked using a spirit level.The first row is placed on a stretched string from the corner.
- adhesive mass applied in a thin layer on the blocks and laid the first row.Each packed unit checked the level of the horizontal and vertical planes, if necessary, blocks inciting a special rubber mallet.
- When stacking blocks in a series of space between them is less than the standard length, it is necessary to make additional element.To do this by hand or electric saws cut the required length of the aerated concrete block and trimmed saw cut grinding or board a plane.
Tip: It is important when installing such an element fluff adhesive composition and its end adjacent to the main series.It should be remembered at any stage of construction of the wall, if the block has sections, it is necessary to handle it with adhesive on all sides to add strength erected structure.
- second and subsequent rows of stacked angle offset polbloka on the right or left (at least 8-10 cm).For the device more robust masonry before proceeding to install the second row, you should wait 2-3 hours for the grout of the first row.With brush sweeps all the small particles and dust.In cases of excess solution, such stains clean off, but not overwritten.
- In order to achieve optimum flatness series is recommended to install wooden structures in the entire series, or in the corners.Aligning the horizon and vertically made after each row.If even small differences remain, this could lead to stress in some areas, and further cracking.
- should refrain from unpacking all items of aerated concrete at a time, as the impacts of precipitation and various atmospheric phenomena material can reduce their technical parameters.If during the construction starts to rain, the unfinished masonry must be protected film, and when you stop work for the winter necessarily thoroughly isolate the structure from moisture.On hot days, aerated concrete blocks set is recommended to moisten with water.
- Upon completion of construction of the building of aerated concrete is best to leave the structure for some time to shrink.As a rule, the structure of porous concrete does not give a large shrinkage and on the expiration of 1-2 months can begin to interior decoration.
- Furnish produced inside the building before the finish of the facade, as moisture formed by pouring floors and painting works should go outside.
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