Concrete. Characteristics, Properties, Application.

Bases, slabs of slabs, reinforced concrete pillows of advertising constructions, bearing walls - all this is a foundation reinforced concrete structure.

Concrete, reinforced concrete is the main means of monolithic housing construction in Russia. A feature of these designs is the combination of metal bonds and cement mortar. How to choose the necessary combination, under what conditions are used those or other materials I will tell in this article

The main properties of concrete, characterizing its quality component, are:

1) The strength of concrete (denoted by a digital index, usually 7.5, 10, 12.5, 20, 25, 30). Characterizes the allowable pressure on concrete, more precisely its compressive strength in Megapascal (N / m2). For example, for concrete grade B20 the ultimate strength is 20MPa. Strength of concrete is checked with special measuring tools: Schmidt's hammer, Kashkarova Onyx hammer, etc.

2) Water-resistant. It is designated by the letter W with an index from 2 to 20. It characterizes the maximum permissible pressure of the water column of a liquid per square centimeter of the area of concrete at which the properties of concrete do not change.

When designing structures working in an aggressive environment (treatment facilities, aerotanks, sewage shafts and canals), additional waterproofing of the fundamental walls is required. It would seem that conventional waterproofing with bituminous mastic, or fusible plastic insulation can solve this problem. But not everything is so simple. Strongly aggressive environment adversely affects the waterproofing materials, bitumen mastigue dissolves in the environment of CO2, and the plastic exfoliates. But there is a solution. Using penetrating waterproofing is the best solution for aggressive environments. What it is?! Penetrating waterproofing is simply a crystallizing hydrophobic additive in concrete, which increases its water resistance by at least 1 point (by 10-15%). The crystals of additives fill the porosity in the concrete and, when moisture penetrates, are activated, causing the main moisture and crystallizing in the pores. The main brands of hydrophobes are Penitron, Crystallisol. The volume fraction of the substance in concrete is 12-12.5 kg. Per m3 of concrete.

3) Frost resistance. Designation letter F. Characterizes the number of cycles of freezing and thawing of concrete after which concrete does not lose its mechanical properties.