Pile foundation anti-freezing and anti-pulling structure for hydrophobic improvement of soil body around pile and construction method of pile foundation anti-freezing and anti-pulling structure

Abstract

The invention discloses a pile foundation anti-freezing and anti-pulling structure for hydrophobic improvement of soil around a pile and a construction method, and relates to the technical field of water conservancy and hydropower engineering structures, the pile foundation anti-freezing and anti-pulling structure comprises hydrophobic improved soil, a surface anti-scour embankment layer, a geomembrane isolation layer, an anti-icing coating and a base layer, the surface of the base layer is provided with the hydrophobic improved soil, and the surface of the base layer is provided with the anti-scour embankment layer; the surface of the hydrophobic improved soil is covered with a geomembrane isolation layer, and the top of the hydrophobic improved soil is horizontally provided with a surface anti-scour mutually-built layer; a pile body vertically penetrates through the middle of the hydrophobic improved soil, and the surface of the pile body is covered with an anti-icing coating. According to the pile foundation anti-freezing and anti-pulling structure for hydrophobic improvement of the soil body around the pile and the construction method, water migration can be avoided and foundation frost heaving can be eliminated during hydrophobic improvement and freezing of the soil body, and the anti-icing coating is adopted around the pile, so that ice crystals are difficult to adhere to the pile body, the soil body around the pile and the pile body are difficult to freeze together, and the pile foundation anti-freezing and anti-pulling effect is achieved. The structure can greatly reduce the tangential frost heaving force, and the pile body is prevented from being damaged by freezing and pulling.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy and hydropower engineering structures, and in particular to a pile foundation anti-freezing and pulling-out structure for improving the water repellency of soil around the pile and a construction method. Background Art

[0002] In cold regions of my country such as Heilongjiang, Jilin, Liaoning and Xinjiang, aqueduct pile foundations are often damaged by frost heave, that is, the pile body moves upward under the action of tangential frost heave force; the upward movement of the pile body can lead to serious consequences such as pile fracture and instability of the upper structure; therefore, in actual projects, measures should be taken to reduce or eliminate the tangential frost heave force to ensure the safe use of the structure.

[0003] When the moisture in the soil around the pile foundation freezes into ice, the ice will bond the surface of the pile foundation with the surrounding soil particles to form freezing force; when the soil around the pile foundation frost-heaves, the frost-heave deformation of the soil close to the pile is constrained, and then an upward tangential frost-heave force is generated along the side surface of the foundation; therefore, the generation of tangential frost-heave force must meet two conditions, namely, the existence of freezing force between the pile and the foundation, and the foundation soil frost-heaves during the freezing process; reducing or eliminating the tangential frost-heave force should start with the three basic frost-heave factors of temperature, soil quality and moisture; if one of these factors can be eliminated or weakened, the purpose of eliminating or reducing frost-heave can be achieved. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides a pile foundation anti-freezing and pulling structure and a construction method that improves the water repellency of the soil around the pile, solving the anti-freezing and pulling problem of aqueduct pile foundation in cold areas raised in the above background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a pile foundation anti-freezing pullout structure with hydrophobic improvement of the soil around the pile, comprising hydrophobic improved soil, a surface anti-scouring masonry layer, a geomembrane isolation layer, an anti-icing coating and a base layer, wherein the surface of the base layer is provided with hydrophobic improved soil, the surface of the hydrophobic improved soil is covered with a geomembrane isolation layer, and the top of the hydrophobic improved soil is horizontally provided with a surface anti-scouring interlayer;

[0006] A pile body is vertically penetrated through the middle of the hydrophobic improved soil, and the surface of the pile body is covered with an anti-icing coating.

[0007] Optionally, the hydrophobic improved soil is prepared by mixing liquid petroleum asphalt and a chemical surfactant solution with soil.

[0008] Optionally, the liquid petroleum asphalt accounts for 7±1% of the soil weight, and the chemical surfactant solution accounts for 0.1±0.03% of the soil weight.

[0009] Optionally, the surface anti-scouring protective masonry layer adopts one or more of mortar masonry, dry masonry, and gabion stone cage;

[0010] Among them, the thickness of the protective masonry is 20-40cm.

[0011] Optionally, the spraying thickness of the anti-icing coating needs to be greater than 2 mm.

[0012] Optionally, the hydrophobic improved soil is filled within the freezing depth around the pile, and its filling thickness needs to be greater than 30 cm.

[0013] A construction method for a pile foundation anti-freezing and pulling structure for improving the water repellency of soil around the pile, comprising the following steps:

[0014] (1) Excavate the soil around the pile, crush it and air dry it;

[0015] (2) heating the soil to 120-150°C;

[0016] (3) introducing the heated petroleum asphalt and chemical surfactant solution and stirring them evenly;

[0017] (4) After cleaning the pile surface and drying it, apply an anti-icing coating;

[0018] (5) After the excavation surface around the pile is cleaned up and the geomembrane is laid, the prepared hydrophobic soil is filled in and compacted layer by layer;

[0019] (6) Protect the ground around the piles with masonry.

[0020] Optionally, the content of particles with a particle size greater than 5 mm after crushing in step 1 needs to be less than 9% of the total soil.

[0021] The present invention provides a pile foundation anti-freezing and pulling structure and a construction method for improving the water repellency of the soil around the pile, which has the following beneficial effects:

[0022] The pile foundation anti-freezing and uplift structure that improves the soil around the pile to be hydrophobic can improve the soil to be hydrophobic, avoid water migration during freezing, eliminate frost heave of the foundation, and use an anti-icing coating around the pile to make it difficult for ice crystals to adhere to the pile body and the soil around the pile to freeze together with the pile body. This structure can greatly reduce the tangential frost heave force and avoid freeze heave damage to the pile body. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a front view full cross-sectional schematic diagram of the invention;

[0024] Figure 2 It is a partial enlarged schematic diagram of the invention.

[0025] In the figure: 1. Hydrophobic improved soil; 2. Surface anti-scouring masonry layer; 3. Geomembrane isolation layer; 4. Anti-icing coating; 5. Base layer; 6. Pile body. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0027] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] See also Figure 1 to Figure 2 The present invention provides a technical solution: a pile foundation anti-freezing and pulling structure for hydrophobic improvement of soil around the pile, comprising hydrophobic improved soil 1, a surface anti-scouring masonry layer 2, a geomembrane isolation layer 3, an anti-icing coating 4 and a base layer 5, the surface of the base layer 5 is provided with hydrophobic improved soil 1, the surface of the hydrophobic improved soil 1 is covered with a geomembrane isolation layer 3, and the top of the hydrophobic improved soil 1 is horizontally provided with a surface anti-scouring interlayer 2;

[0030] A pile body 6 vertically penetrates the middle of the hydrophobic improved soil 1 , and the surface of the pile body 6 is covered with an anti-icing coating 4 .

[0031] In this embodiment, Figure 1 and Figure 2 As shown, the hydrophobic improved soil 1 is formed by mixing liquid petroleum asphalt and a chemical surfactant solution with soil.

[0032] In this embodiment, Figure 1 As shown, liquid petroleum asphalt accounts for 7% of the soil weight and chemical surfactant solution accounts for 0.1% of the soil weight.

[0033] In this embodiment, Figure 1 and Figure 2 As shown, the surface anti-scouring protective masonry layer 2 is made of one or more of mortar masonry, dry masonry, and gabion stone cage;

[0034] Among them, the thickness of the protective masonry is 25cm.

[0035] In this embodiment, Figure 1 As shown, the spraying thickness of the anti-icing coating 4 needs to be greater than 2 mm.

[0036] In this embodiment, Figure 1 As shown, the hydrophobic improved soil 1 is filled within the freezing depth around the pile, and its filling thickness needs to be greater than 30 cm.

[0037] A construction method for a pile foundation anti-freezing and pulling structure for improving the water repellency of soil around the pile, comprising the following steps:

[0038] (1) The soil around the pile is excavated and crushed and air-dried. The content of particles with a diameter greater than 5 mm after crushing must be less than 9% of the total soil;

[0039] (2) heating the soil to 128.5°C;

[0040] (3) introducing the heated petroleum asphalt and chemical surfactant solution and stirring them evenly;

[0041] (4) After cleaning and drying the surface of the pile body 6, apply the anti-icing coating 4;

[0042] (5) After the excavation surface around the pile is cleaned up and the geomembrane is laid, the prepared hydrophobic soil is filled in and compacted layer by layer;

[0043] (6) Protect the ground around the piles with masonry.

[0044] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A pile foundation anti-freezing and pulling structure for hydrophobic improvement of soil around the pile, comprising hydrophobic improved soil (1), a surface anti-scouring and protective masonry layer (2), a geomembrane isolation layer (3), an anti-icing coating (4) and a base layer (5), characterized in that: The surface of the base layer (5) is provided with hydrophobic improved soil (1), the surface of the hydrophobic improved soil (1) is covered with a geomembrane isolation layer (3), and the top of the hydrophobic improved soil (1) is horizontally provided with a surface anti-scour interlayer (2); A pile body (6) vertically penetrates the middle of the hydrophobic improved soil (1), and the surface of the pile body (6) is covered with an anti-icing coating (4).

2. The pile foundation anti-freezing and pulling structure for improving the water repellency of the soil around the pile according to claim 1, characterized in that: The hydrophobic improved soil (1) is prepared by mixing liquid petroleum asphalt and a chemical surfactant solution with soil.

3. The pile foundation anti-freezing and pulling structure for improving the water repellency of the soil around the pile according to claim 2, characterized in that: The liquid petroleum asphalt accounts for 7±1% of the soil weight, and the chemical surfactant solution accounts for 0.1±0.03% of the soil weight.

4. The pile foundation anti-freezing and pulling structure for improving the water repellency of the soil around the pile according to claim 1, characterized in that: The surface anti-scour protection masonry layer (2) is made of one or more of mortar masonry, dry masonry, and gabion stone cages; Among them, the thickness of the protective masonry is 20-40cm.

5. The pile foundation anti-freezing and pulling structure for improving the water repellency of the soil around the pile according to claim 1, characterized in that: The spraying thickness of the anti-icing coating (4) needs to be greater than 2 mm.

6. The pile foundation anti-freezing and pulling structure for improving the water repellency of the soil around the pile according to claim 1, characterized in that: The hydrophobic improved soil (1) is filled within the freezing depth range around the pile, and its filling thickness needs to be greater than 30 cm.

7. A construction method for a pile foundation anti-freezing and pulling structure for improving the water repellency of the soil around the pile as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: (1) Excavate the soil around the pile, crush it and air dry it; (2) heating the soil to 120-150°C; (3) introducing the heated petroleum asphalt and chemical surfactant solution and stirring them evenly; (4) After cleaning the surface of the pile body (6) and drying it, apply an anti-icing coating (4); (5) After the excavation surface around the pile is cleaned up and the geomembrane is laid, the prepared hydrophobic soil is filled in and compacted layer by layer; (6) Protect the ground around the piles with masonry.

8. The pile foundation anti-freezing and pulling structure and construction method for improving the water repellency of the soil around the pile according to claim 7, characterized in that: In the step 1, the content of particles with a particle size greater than 5 mm after crushing must be less than 9% of the total soil.

Images