RU33955U1 - The cooled base of structures - Google Patents

Abstract

1. The cooled base of the structures, containing a bed of soil with a layer of thermal insulation and cooling pipes placed inside it with condensation and evaporation zones, characterized in that the cooling pipes are sealed and consisting of two sections, the first of which is located vertically or deviated from the vertical no more than 30 °, and the second is inclined to the horizon at an angle of no more than 10 °, while in the first section of the pipe on its inner wall below the ground pockets are made to hold I am draining condensate. 2. The cooled base of structures according to claim 1, characterized in that the thermal insulation is located at different levels: on the outside of the structure below the level of the base, and inside the structure above the level of the base. The cooled base of the structures according to claim 1, characterized in that from the outside of the structure along the perimeter of the additional filling.

Description

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IPC: E02D3 / 115

The cooled base of structures

The utility model relates to the construction of foundations of structures constructed in permafrost areas and on soft soils.

Features of the construction of the foundations of structures are determined by the specific conditions in the high-latitude regions of the North. In winter, the air temperature there remains within minus 20 - minus 40 °. However, the thermophysical properties of soils are such that even at a depth of 1.5 m, the temperature of the soil does not drop below 8 -10 C. In the summer (July - August), frozen soil melts under the influence of heat, and this creates a threat of deformation of the foundations of buildings and facilities. Therefore, there is a need for a significant extension of the frozen state of the soil in the summer. This is achieved by additional cooling the soil at depths of up to two to three meters to a temperature of minus 15 ° - minus C using cooling units. This ensures the maintenance of frozen soil for the entire summer period, and, consequently, the preservation of the bearing capacity of the soil.

A known construction of the foundation for the outer walls of buildings, containing one-pipe, two-pipe or three-pipe curved cooling units located along the foundation at a distance of 3-4 m from each other (Gapeev SI, “Strengthening frozen bases by cooling L., 1977, p. 58 -60).

The closest in technical essence to the proposed utility model is the design of the bulk cooled base of structures, containing cooling pipes connected to the condenser part, and layers of thermal insulation placed above them and soil filling, with

this cooling, pipes filled with low-boiling liquid are placed inside the protective pipes made with a thickened end on one side and an open end on the other, and a cavity filled with heat-conducting liquid, and the protective pipes are located under the filling of the soil and a layer of insulation with a slope of 10 ° to the longitudinal the axis of the base towards the thickened ends, and the open ends are taken out of the boundaries of the soil dumping contour (see RF patent No. 2157872, EV 3/115, publ. 10/20/2000)

In this design, the condenser part and the cooling pipes are filled with a low boiling liquid, for example propane. When lowering the temperature of the atmospheric air and the temperature of the soil, the circulation of the gas-liquid flow in the system begins: the condenser part is the cooling pipes, accompanied by the removal of heat from permafrost.

A disadvantage of the known design is its low thermal efficiency due to the large extent of the vapor-liquid tract. The base of the structure is thawed, especially in the area where the pipes enter the soil, even during the spring and autumn frosts. For the same reason, it is difficult to start the device in operation, especially with daily temperature fluctuations. In addition, the cooling pipes are interconnected, and the failure of one pipe disrupts the circulation of the gas-liquid flow of the entire system.

The technical problem solved by this utility model is to increase the cooling efficiency of the foundation.

To this end, in the known construction of a bulk cooled foundation of structures containing soil sprinkling with a heat insulation layer located on it and cooling pipes with condensation and evaporation zones placed inside it, it is new that each cooling pipe is sealed and consists of two sections, the first of which is located vertically or deviated from the vertical by no more than 3 °, and the second is inclined to the horizon at an angle of no more than 10 °, while in the first section of the pipe on its inner wall the level of soil formed pockets for retention flowing condensate.

In addition, the insulation is located at different levels: on the outside of the structure below the level of the base, and inside the structure above the level of the base, while on the outside of the structure along its perimeter an additional dumping is performed to prevent air from entering the structure.

In the proposed utility model, the cooling of the base is carried out by several separate pipes, in which the distance between the condenser and the inclined part (evaporator) is much smaller than in the prototype, where the cooling pipes are connected in series and, therefore, have an extended vapor-liquid path. For this reason, the effectiveness of freezing the base in the proposed solution is significantly higher than in the prototype.

The implementation of capillary pockets on the inner surface of the pipe in the surface layer helps to start the cooling pipe in operation with small temperature differences between air and the surface layer of soil at the pipe inlet to the ground. Freezing of the soil occurs even during night frosts in the spring-autumn period, which delays the thawing of the soil associated with large heat inflows along the walls of the pipe.

The proposed utility model is illustrated by drawings.

Pa fig. 1 shows the design of the bulk cooled base of structures, General view;

in FIG. 2 is a view aa of FIG. 1.

in FIG. 3 - design of cooling pipes in the near-surface layer at the entrance to the soil.

The design of the bulk cooled base of the structures contains a bed of soil 1 with a height of about 2 meters, inside which there are cooling pipes 2. Cooling pipes 2 consist of two sections: the first 3 is located vertically or deviated from the vertical by no more than 30 °, and is led out to one end; the second section 4 is located obliquely to the horizon at an angle of no more than southeast and is located under building 5.

On the soil backfill 1, outside the structure 5, there is a 6-a insulation layer with thermal resistance I, 3.0 deg / W, the upper boundary of which is approximately at the level of the lower boundary of the base of the structure. Inside the structure, the thermal insulation layer 6-6 is located above the level of the lower boundary of the base.

The cooling pipes are pre-charged with a low boiling liquid, such as ammonia. On the inner wall of the vertical pipe 3 in the evaporation zone below the soil level, pockets 7 are made for trapping condensate / flowing down the inner surface of the pipe. Pockets can be made circular, spiral or have a different shape. Due to this, an increase in the surface of the pipe moistened with coolant is achieved, and, consequently, an increase in the efficiency and reliability of the device.

On the outside of the structure along its perimeter an additional dumping 8 was made to prevent air from entering the building from the atmosphere.

The construction of the described base is as follows. On natural permafrost soil, sand filling is carried out about two meters high, then trenches are made in the dumping perpendicular to the longitudinal axis of the future foundation with a depth of 0.8 - 1.5 m at a distance of 2-3.5 m from each other. The peripheral trenches are dug so that the pipes laid in them are approximately under the walls of the structure. Then, cooling pipes are laid in the trenches and fixed with a slight slope (0-10 °) perpendicular to the longitudinal axis of the base. The surface of the soil filling is leveled and the foundation of the structure is installed on it. Outside, on the outside of the base, a heat insulation layer 6-a and 6-6 with a width of 1-1.5 m is laid on the surface to prevent the soil from being thawed 1. The inside of the structure is mixed, the heat insulation layer is shed, which reduces the heating of the central frozen part of the foundation .

On the outside of the base, an additional dump 8 is constructed to prevent air from entering the atmosphere under the structure.

When the temperature of the air drops below the soil temperature, the circulation of the gas-liquid flow in the system begins, accompanied by the removal of heat from the soil adjacent to the cooling pipes 2. The proposed pipe design allows for uniform cooling of the soil along the entire length of the pipes, not only on its inclined, but also on the vertical section . In the warm season, the thermal insulation layer 6 prevents the thawing of the soil dumping 1.

The described cooled base for structures is quite simple to maintain, reliable in operation and does not require the use of expensive equipment.

Using the proposed utility model increases the effectiveness of soil freezing and increases the shelf life of the soil in a frozen state.

Claims (3)

1. The cooled base of the structures, containing a bed of soil with a layer of thermal insulation and cooling pipes placed inside it with condensation and evaporation zones, characterized in that the cooling pipes are sealed and consisting of two sections, the first of which is located vertically or deviated from the vertical no more than 30 °, and the second is inclined to the horizon at an angle of no more than 10 °, while in the first section of the pipe on its inner wall below the ground pockets are made to hold I am flowing down condensate. 2. The cooled base of structures according to claim 1, characterized in that the thermal insulation is located at different levels: on the outside of the structure below the level of the base, and inside the structure above the level of the base. 3. The cooled base of structures according to claim 1, characterized in that from the outside of the structure along the perimeter of the additional filling.