An elastic pile foundation resistant to frost heave damage

Abstract

The invention discloses an elastic pile foundation that resists frost heave damage. The top connection module of the device is installed above the frost heave buffer module, and a gravity column module is installed below the frost heave buffer module. A lifting plate that can slide axially along the inner side of the support shaft is installed in the support shaft of the frost heave buffer module, and a rotating shaft seat I is fixedly installed on the edge of the lifting plate. The rotating shaft seat I is axially connected to one end of the supporting crossbeam, and the other end of the supporting crossbeam is axially connected to the rotating shaft seat II. The rotating shaft seat II is fixedly installed on the elastic buffer strip, and a buffer net is fixedly installed on the elastic buffer strip. A screw rod is installed in the top connection module, and a driven gear is fixedly installed on the top of the screw rod. The driven gear is meshed with the driving gear, and the driving gear is fixedly installed with the crank shaft. The present invention can be adjusted according to the actual frozen soil layer depth of the project; it can adapt to repeated freezing and thawing, effectively prevent frost heave and frost pullout, and the effect is long-lasting; it can be completely dismantled and recycled, and has little impact on the environment; modular assembly is convenient for later maintenance and reduces maintenance costs.

Description

Technical Field

[0001] The invention belongs to the technical field of anti-freezing and heaving foundation, and in particular relates to an elastic pile foundation that resists frost heaving damage. Background Art

[0002] Frozen soil refers to various soils and rocks below zero degrees Celsius and containing ice. Frozen soil is widely distributed in my country, and the total distribution area of ​​permafrost and seasonal frozen soil accounts for almost two-thirds of the country's total land area. Frozen soil is extremely sensitive to temperature. When carrying out basic construction construction such as buildings in frozen soil areas, the impact of frozen soil heaving and melting settlement must be considered. With the alternation of seasons, the foundations of facilities in frozen soil areas are often damaged by repeated freezing and thawing, which often manifests as serious problems such as foundation fractures due to the shear force of frozen soil, lateral tilting or displacement due to non-uniform stress, and foundation displacement due to freezing. Solving the adverse effects of frozen soil on engineering foundations is of great significance to engineering construction in frozen soil areas.

[0003] At present, the main methods to solve the frost heave problem in frozen soil areas are summarized as follows: ① Reduce the soil moisture content within the freezing depth range; ② Add structures to resist soil deformation or absorb shear or stress near the foundation at the freezing depth; ③ Increase the strength of the foundation itself. The most widely used method in engineering practice is to replace a certain thickness of non-frost heave medium sand and coarse sand around the foundation within the designed freezing depth to reduce the tangential frost heave force, or mix hydrophobic materials into the frozen soil. In addition, the surface near the foundation is waterproofed by strong tamping, thereby weakening or eliminating the infiltration of surface water and preventing the upward movement of groundwater, so as to reduce the water content of the soil and achieve the purpose of weakening frost heave. This method has the following disadvantages: ① Increase the amount of foundation excavation, consume a lot of sand and stone materials, increase manpower consumption and increase construction costs, and make later maintenance difficult and costly; ② After repeated freezing and thawing, it will lose some functions, and its anti-frost heave effective period is not long, and the effect is not good; ③ The effective treatment depth of strong tamping and other methods is limited, and it is easy to affect nearby buildings; ④ The environmental impact is large, and the added hydrophobic substances are not environmentally friendly and not sustainable. Summary of the invention

[0004] The purpose of the present invention is to provide an elastic pile foundation that is resistant to frost heave and damage in response to the problems existing in the above-mentioned prior art, which can achieve the following: 1. The effective treatment depth is not limited and can be adjusted according to the actual depth of the frozen soil layer of the project; 2. It can adapt to repeated freezing and thawing, has high stability, can effectively prevent frost heave and frost pullout, and has a lasting effect; 3. It can be completely dismantled and recycled, with little impact on the environment; 4. Modular assembly is convenient for later maintenance and reduces maintenance costs; 5. Reduces construction difficulty and labor intensity, saving costs.

[0005] The technical solution created by the present invention is implemented as follows: a top connection module 1 of an elastic pile foundation that resists frost heave damage is installed above a frost heave buffer module 2, a gravity column module 3 is installed below the frost heave buffer module 2, a lifting plate 207 that can slide axially along the inside of the support shaft 202 is installed in the support shaft 202 of the frost heave buffer module 2, the lifting plate 207 has an internal thread, and cooperates with the external thread of the screw rod 104 to achieve axial lifting, a rotating shaft seat I 206 is fixedly installed on the edge of the lifting plate 207, the rotating shaft seat I 206 is axially connected to one end of the supporting beam 204, and the other end of the supporting beam 204 is axially connected to the rotating shaft seat II 205, and the rotating shaft seat II 205 is fixedly installed on the elastic buffer On the punch bar 201, a buffer net 203 is fixedly installed on the elastic buffer bar 201; a screw rod 104 is installed in the top connection module 1 of an elastic pile foundation that resists frost heave damage, and a driven gear 103 is fixedly installed on the top of the screw rod 104, and the driven gear 103 is meshed with the driving gear 102, and the driving gear 102 is fixedly installed with the crank shaft 101; a water collecting tray 301 of a gravity column module 3 of an elastic pile foundation that resists frost heave damage is fixedly installed with the gravity column 302, and there are reserved holes on the water collecting tray 301, and the reserved holes are connected with the water drop holes in the gravity column 302; through the support shaft 202 of the frost heave buffer module 2, multiple frost heave buffer modules 2 can be assembled in series into one.

[0006] The invention has a novel, reasonable and simple structure. By assembling a plurality of frost heave buffer modules in series, the effective treatment depth is not limited and can be adjusted according to the actual frozen soil depth of the project. The elastic deformation of the elastic buffer strip can adapt to repeated freezing and thawing, and the stability is high. It can effectively prevent frost heave and frost pullout with a lasting effect. The frost heave buffer module is driven to be retracted and released through the rotation of the gear set and the screw rod, and can be completely dismantled and recycled with less impact on the environment. The modular assembly can reduce the construction difficulty and labor intensity on the one hand, and facilitate later maintenance and reduce maintenance costs on the other hand. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a schematic diagram of the overall structure of an elastic pile foundation that resists frost heave damage;

[0008] Figure 2 It is a perspective view of the internal structure of the top connection module;

[0009] Figure 3 is a schematic diagram of the top structure of the frost heave buffer module;

[0010] Figure 4 is a schematic diagram of the internal structure of the frost heave buffer module;

[0011] Figure 5 This is the bottom structure diagram of the frost heave buffer module.

[0012] Figure 6It is a schematic diagram of the gravity column structure.

[0013] Description of part numbers in the figure:

[0014] 1. Top connection module; 101. Crank shaft; 102. Driving gear; 103. Driven gear; 104. Screw rod; 2. Frost heave buffer module; 201. Elastic buffer strip; 202. Support shaft; 203. Buffer net; 204. Support beam; 205. Shaft seat II; 206. Shaft seat I; 207. Lifting plate; 3. Gravity column module; 301. Water collecting tray; 302. Gravity column. DETAILED DESCRIPTION

[0015] The following is a detailed description of the implementation scheme of the invention in conjunction with the accompanying drawings. A top connection module 1 of an elastic pile foundation that resists frost heave damage is installed above a frost heave buffer module 2, and a gravity column module 3 is installed below the frost heave buffer module 2. A lifting plate 207 that can slide axially along the inside of the support shaft 202 is installed in the support shaft 202 of the frost heave buffer module 2. The lifting plate 207 has an internal thread that cooperates with the external thread of the screw rod 104 to achieve axial lifting. A rotating shaft seat I 206 is fixedly installed on the edge of the lifting plate 207. The rotating shaft seat I 206 is axially connected to one end of the supporting beam 204, and the other end of the supporting beam 204 is axially connected to the rotating shaft seat II 205. The rotating shaft seat II 205 is fixedly installed on the elastic buffer strip 201. A buffer net 203 is fixedly installed on the elastic buffer strip 201; a screw rod 104 is installed in the top connection module 1 of an elastic pile foundation that resists frost heave damage, and a driven gear 103 is fixedly installed on the top of the screw rod 104, and the driven gear 103 is meshed with the driving gear 102, and the driving gear 102 is fixedly installed on the crank shaft 101; a water collecting tray 301 of a gravity column module 3 of an elastic pile foundation that resists frost heave damage is fixedly installed on the gravity column 302, and there are reserved holes on the water collecting tray 301, and the reserved holes are connected with the water holes in the gravity column 302; through the support shaft 202 of the frost heave buffer module 2, multiple frost heave buffer modules 2 can be assembled in series into one.

[0016] During operation, a hole is drilled at a preset position on the ground, and the radius of the drilled hole is slightly larger than the gravity column module 3. The frost heave buffer module 2 is installed below the top connection module 1, so that the screw rod 104 of the top connection module 1 passes through the support shaft 202 of the frost heave buffer module 2, and the outer thread of the screw rod 104 is meshed with the inner thread of the lifting plate 207. According to the depth of the frozen soil layer, multiple frost heave buffer modules 2 are assembled in series through the screw rod 104, and finally the gravity column module 3 is assembled below the frost heave buffer module 2 of the lowest layer through the reserved inner thread hole and the screw rod 104. At this point, an elastic pile foundation resistant to frost heave damage is assembled, and the elastic pile foundation resistant to frost heave damage is hoisted into the drilled hole, and the crank shaft 101 is driven to rotate by a crank or a motor, so that it drives the driving gear 102 and the driven gear 103 to rotate, and then drives the screw rod 104 to rotate. Under the rotation of the screw rod 104, the lifting plates 207 of multiple frost heave buffer modules 2 descend along the axis of the screw rod 104, and the supporting beam 204 rotates relatively around the lifting plate 207 through the rotating shaft seat I 206, and the supporting beam 204 is opened through the rotating shaft seat II 205, so that the elastic buffer strip 201 and the buffer net 203 press the wall of the drilled hole with appropriate stress. After reaching the preset stress, the installation and embedding work of the elastic pile foundation resistant to frost heave damage is completed, and the upper equipment or building can be fixed on the top connection module 1 as required. During the non-freezing period, the excess water in the soil or the infiltration water in the soil will eventually flow into the water collecting tray 301 along the buffer net 203 and the elastic buffer strip 201 and be diverted to the soil layer below the non-freezing depth through the water drop hole in the gravity column 302. During the freezing period, the soil water undergoes a phase change due to freezing, causing the soil to expand unevenly. At this time, the wall of the drilled hole compresses part of the buffer net 203 and the elastic buffer strip 201, and the part of the elastic buffer strip 201 is deformed under force. Relative to the whole, the support shaft 202 can still maintain its original position and corresponding support foundation function. During the freeze-thaw period, the pressure of the hole wall on the part of the buffer net 203 and the elastic buffer strip 201 gradually decreases during the melting of the frozen soil. At this time, the elastic buffer strip 201, under the reset effect of its own toughness, is supported by the support beam 204 and pressed against the hole wall, always keeping the support shaft 202 uniformly stressed in the soil layer, so as not to deflect or displace and destroy its function.

Claims

1. An elastic pile foundation that resists frost heave damage, characterized in that: The top connection module (1) is installed above the frost heave buffer module (2), and a gravity column module (3) is installed below the frost heave buffer module (2). A lifting plate (207) that can slide axially along the inside of the support shaft (202) is installed in the support shaft (202) of the frost heave buffer module (2). The lifting plate (207) has an internal thread that cooperates with the external thread of the screw rod (104) to achieve axial lifting. A rotating shaft seat I (206) is fixedly installed on the edge of the lifting plate (207). The rotating shaft seat I (206) is axially connected to one end of the supporting beam (204), and the other end of the supporting beam (204) is axially connected to the rotating shaft seat II (205). The shaft seat II (205) is fixedly mounted on the elastic buffer strip (201), and a buffer net (203) is fixedly mounted on the elastic buffer strip (201); a screw rod (104) is installed in the top connection module (1), and a driven gear (103) is fixedly mounted on the top of the screw rod (104), and the driven gear (103) is meshed with the driving gear (102), and the driving gear (102) is fixedly mounted on the crank shaft (101); the water collecting tray (301) of the gravity column module (3) is fixedly mounted on the gravity column (302), and a reserved hole is provided on the water collecting tray (301), and the reserved hole is connected to the water drop hole in the gravity column (302).

2. The frost heave resistant elastic pile foundation according to claim 1, characterized in that: A plurality of frost heave buffer modules (2) can be assembled in series into one body via the support shaft (202) of the frost heave buffer module (2).

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