Gas silicate blocks, the technical characteristics of which will be presented in the article, are quite common today. This is due to the fact that this cellular concrete has low weight and excellent quality.
The composition of gas silicate
In the manufacture of the products mentioned, high-quality Portland cement is used, the ingredients of which should contain calcium silicate in a volume equal to ½ of the total weight. Among other things, sand is added to the mixture in which there is quartz (85% or more). While silt and clay in this component should not be more than 2%. Kipelka lime is also added during the production process, the quenching rate of which is about 5-15 minutes, but calcium and magnesium oxide should be about 70% or more in it. Products also include a gasifier, which is made of aluminum powder. There is a liquid in the blocks, as well as sulfanol C.
Gas silicate blocks, the price of which will be presented below, can be manufactured using an autoclave or without it. The first production method allows you to form blocks whose strength is much higher, their shrinkage is also not so impressive that it is appreciated by consumers.
Products that are manufactured using an autoclave but do not go through the drying stage have 5 times more impressive shrinkage compared to blocks that are dried in an autoclave, in addition, they do not have such impressive strength, but they cost less.
The autoclave production method is used, as a rule, in large enterprises, this is due to the fact that this method is technological and involves the expenditure of a large amount of energy. The blocks in the production process go through a steaming stage at 200 0 , while the pressure reaches a value of 1.2 MPa. Manufacturers change the ratio of ingredients that are part of the mixture, which allows you to change the characteristics of the material. For example, with an increase in the volume of cement, the strength of the block will be increased, however, the porosity will be reduced, which as a result will affect the thermal performance, and the thermal conductivity will be significantly increased.
Specifications
Gas silicate blocks, the technical characteristics of which are preferable to consider before purchase, are divided into types by density. Depending on this indicator, the blocks can be structural, heat-insulating and structural-heat-insulating. Structural products are those that have a density denoted by the D700 brand, but no less. These products are used in the construction of load-bearing walls in buildings whose height does not exceed 3 floors. Structural and heat-insulating products have a density in the range of D500-D700. This material is ideally suited for the construction of interior partitions and walls of buildings whose height does not exceed 2 floors.
Gas silicate heat-insulating blocks, the technical characteristics of which are important to know before using them in the construction of walls, have quite impressive porosity, this indicates that their strength is the lowest. Their density is equal to the limit of D400, they are used in the role of a material that is able to increase the thermotechnical qualities of walls built from not so energy-efficient materials.
Thermal conductivity
In terms of thermal conductivity, gas silicate has quite impressive characteristics. Thermal conductivity is directly dependent on density. So, a gasolate of grade D400 or lower has a thermal conductivity of 0.08-0.10 W / m ° C. As for the blocks of the D500-D700 brand, the mentioned indicator ranges from 0.12 to 0.18 W / m ° . Blocks of the brand D700 and higher have a thermal conductivity in the range 0.18-0.20 W / m ° C.
Frost resistance
Gas silicate blocks, the technical characteristics of which you should definitely find out before making a purchase, also have certain frost resistance properties, which depend on the number of pores. Thus, various gas silicate-based blocks can withstand approximately 15-35 freezing and thawing cycles. However, technological development does not stand still, and some enterprises have learned to produce blocks that are able to undergo such cycles up to 50, 75 and even 100 times, which is very attractive, as is the weight of the gas silicate block. But if you purchase products that were manufactured according to GOST 25485-89, then when building a house, you need to focus on the frost resistance index of the D500 brand, equal to 35 cycles.
Dimensions and mass of blocks
Before you begin to build walls of gas silicate blocks, you need to find out what sizes products can have. As a rule, blocks with sizes equal to 600x200x300, 600x100x300, 500x200x300, 250x400x600, and also 250x250x600 mm are presented for sale, but this is not a complete list.
The mass of the block depends on the density. So, if the unit has the brand D700, and its dimensions are in the range of 600x200x300 mm, then the weight of the unit will vary from 20 to 40 kg. But the brand of the D700 block with dimensions within 600x100x300 mm has a weight equivalent to 10-16 kg. Blocks with a density of D500 to D600 and dimensions of 600x200x300 mm have a weight of 17 to 30 kg. For the density of the D500-D600 gas silicate and its size in the block 600x100x300 mm, the weight will be 9-13 kg. With a density in D400 and dimensions equal to 600x200x300 mm, the mass will be equal to 14-21 kg. The D400 gas silicate grade, enclosed in dimensions of 600x100x300 mm, will weigh approximately 5-10 kg.
Positive aspects of gas silicate block
When you know the thickness of the gas silicate block, you can learn about its other characteristics, including the positive and negative sides. Among the pluses, one can distinguish low weight, as well as strength, which is sufficient for low-rise construction. In addition, such products have excellent heat saving qualities. Noise goes badly through such walls, and the cost of the products remains affordable. Blocks do not burn. Building with gas silicate blocks is possible on the basis of special adhesives, which allow to obtain a seam of minimum thickness.
Negative qualities
Considering the disadvantages of gas silicate blocks, we can highlight the need for external decoration, which increases the aesthetics of the walls. Blocks are not so attractive when the consumer learns about their hygroscopic properties. And before construction begins, a solid foundation is required.
Block price
Gas silicate blocks, the price of which can vary depending on the size, it is permissible to lay on their own. Their weight does not imply the use of special equipment. Thus, if the block has a size in the range of 600x100x300 mm, then its cost per unit will be equal to $ 1.8-1.9.