Reinforced concrete trays are used, as a rule, in the construction of roads, heating mains, in housing construction and for the needs of water disposal. They provide water resistance, durability and safety of communications, a high level of frost resistance. Such trays are resistant to mechanical stress and allow unhindered maintenance of the system during repair or modernization. Reinforced concrete has high anticorrosive properties, which is due to the use of heavy concrete with a steel reinforcement frame of classes A-1, A-3, Bp-I. This ensures a low accident rate of such structures.
The conditions under which the reinforced concrete trays are intended, and the functions that they must perform, require various modifications (types) of these products.
Types of trays and application features
The trays are divided into several types, which differ in size, shape, principle of drainage and method of installation. The main types:
- trays for heating mains, channels, tunnels (protection from cold, water, ground pressure. Closed, stacked in the ground);
- telescopic trays (for water drainage during the construction of roads, bridges. Stacked with a slope on the principle of tiles);
- feeding bins (for collecting water along sidewalks, highways, parking lots);
- drainage trays (for drainage of ground and storm water from railways, runways and for the construction of hydraulic structures);
- cable trays (to protect against damage to the cable or wires).
Reinforced concrete trays: GOST, operating conditions
The trays are made according to the technology of vibrocompression of a rectangular or parabolic shape. The production is subject to stringent requirements of GOSTs. In projects, trays of typical series are usually laid, on which there are working drawings and recommendations for use.
In accordance with the standards of the Russian Federation, reinforced concrete trays GOST 13015-2003 are manufactured. Concrete for trays must meet the requirements of GOST for frost and water resistance, resistance to aggressive environments, the thickness of the protective layer, corrosion resistance (individual requirements for reinforcement) and certain standards of components.
To prevent clogging of the trays, they are closed with plates.
To ensure resistance to precipitation and strength, reinforced concrete trays are made of concrete of classes B15, B20 and B25.
The outer walls of the trays, which are buried in the ground, are waterproofed with a coating method in two layers of bituminous materials.
If it is planned to operate reinforced concrete trays in aggressive soils, then their walls are covered with special protective compounds.
Dimensions and labeling of trays
Each type of tray has a specific marking written in alphanumeric values.
For example, LC 300.180.90-3. First comes the letter indicating the type of product (LC - channel tray), or size (L-4), the numbers indicate the length, width and height, the vertical load index (tf / m 2 ) is written through the dash. Further, letter designations can also go (ādā - additional, āaā - with mortgages).
They produce reinforced concrete trays, sizes which are selected depending on their purpose, categories and types. They differ in weight, length, width and height, are open and closed. The price depends on the size and the required number of trays.
Plates that are used for the bottom device are marked PT, and for overlapping - PD.