Freeze-thaw deformation prevention and control structure and construction method of railway contact network piles in frozen soil areas

Abstract

The present invention discloses a freeze-thaw deformation prevention and control structure of railway contact network pipe piles in frozen soil areas in the field of pipe piles, including: deep buried piles and welded piles; a heat release chamber and a recovery chamber are arranged inside the deep buried piles; a telescopic airbag is arranged in the heat release chamber, an iron column is arranged on the telescopic airbag, and a working medium is filled in the telescopic airbag; the heat release chamber is filled with iron element; a plurality of air holes are arranged on the side of the heat release chamber; a valve core is arranged in the middle of the top of the recovery chamber, and a partition is arranged between the recovery chamber and the heat release chamber; a plurality of flip doors are arranged on the partition; a material box is arranged at the bottom of the welded pile; an air chamber and a material chamber are arranged in the material box, and a plurality of door panels are arranged in the material chamber; a groove is arranged in the air chamber near the door panel, ratchet teeth are arranged in the groove, and a spring is arranged between the ratchet teeth and the groove. This scheme can reduce the moisture content of the roadbed active layer near the deep buried piles, keep the active layer dry, and thus improve the stability of the deep buried piles.

Description

Technical Field

[0001] The invention belongs to the field of pipe piles, and specifically relates to a freeze-thaw deformation prevention and control structure and a construction method for railway contact network pipe piles in frozen soil areas. Background Art

[0002] The rapid development of the national economy and national strategic needs have led to more frequent railway construction in permafrost areas. However, the development trend of high-speed and heavy-load railways and the harsh environment in permafrost areas have made it difficult for diesel locomotives to adapt to the transportation capacity requirements of railways. Electric locomotives are increasingly widely used due to their high power, strong overload capacity, fast speed, short acceleration and deceleration time, and environmental friendliness. As an important part of the traction power supply system of electrified railways, the long-term stability of the contact network foundation directly affects the safety of train operation. However, under the repeated freezing and thawing of the active layer in permafrost areas, the long-term stability of the contact network piles faces a huge threat. How to solve the problem of freeze-thaw deformation of the contact network piles is the key to ensuring the safe operation of electrified railways in permafrost areas.

[0003] At present, the design and construction theory of freeze-thaw deformation prevention and control of contact network piles in seasonal frozen soil areas is relatively mature, and there are relatively rich engineering backgrounds, such as Harbin-Dalian Line, Harbin-Qiqihar Line and Lanzhou-Xinjiang Line. However, in permafrost areas, the temperature development and moisture migration differences caused by external conditions and underlying permafrost make the freeze-thaw deformation mechanism of contact network piles more complicated, lacking effective freeze-thaw deformation control technology, and there are very limited physical projects and experiences that can be used for reference. The existing freeze-thaw deformation prevention and control measures for pile foundations in permafrost areas mainly include hot rods, isolation agents, pile outer casings, variable cross-sections, and replacement filling. The deformation prevention and control is mainly carried out from two perspectives: improving the anchoring conditions of pile foundations and isolating or weakening the frost heave and cementation of the active layer. However, there are few reports on relevant measures to control the moisture content of the active layer. In addition, the contact network piles in permafrost areas are small in size, light in weight, and shallow in burial depth. The surrounding active layer is mainly roadbed. In addition, their construction should try not to disturb the main structure of the roadbed and the underlying frozen soil, which leads to the limitations of the existing measures in the field of contact network piles in frozen soil areas.

[0004] Considering the urgent need to prevent and control the freeze-thaw deformation of contact network pipe piles in permafrost areas, in order to enrich the freeze-thaw deformation prevention and control technology of similar shallow buried pile foundations, it is necessary to consider controlling the freeze-thaw deformation of contact network pipe piles by changing the moisture distribution conditions of the active layer around the piles. Summary of the invention

[0005] The purpose of the present invention is to provide a freeze-thaw deformation prevention and control structure and a construction method for railway contact network pipe piles in frozen soil areas, which can reduce the water content of the active layer near the pipe piles, thereby reducing the negative impact of the freeze-thaw effect on the pipe piles.

[0006] In order to achieve the above object, the technical solution of the present invention is as follows:

[0007] A freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas, comprising: deep buried piles and welded piles;

[0008] A heat release chamber and a recovery chamber are arranged inside the deep buried pile, and the heat release chamber is located below the recovery chamber; a telescopic airbag is fixedly connected to the bottom of the heat release chamber, an iron column is fixedly connected in the middle of the telescopic airbag, and a working medium is contained in the telescopic airbag; the top of the telescopic airbag in the heat release chamber is filled with iron; a plurality of air holes are arranged on the side of the heat release chamber; a valve core is arranged in the middle of the top of the recovery chamber, a partition is arranged between the recovery chamber and the heat release chamber, and the partition is fixedly connected to the deep buried pile; a plurality of flip doors are arranged on the partition, and the flip doors are all rotatably connected to the partition;

[0009] The welding pile is located above the deep buried pile, and a material box is arranged at the bottom of the welding pile, and the top and bottom of the material box are fixedly connected to the welding pile and the deep buried pile respectively; smooth cushion layers are fixedly connected on all sides inside the material box; an air chamber and a material chamber are arranged in the material box, and a number of door panels are arranged in the material chamber, and the door panels slide in cooperation with the material box, and the door panels divide the material chamber into a number of small material chambers; the air chamber and the material chamber are separated by door panels; a groove is arranged in the air chamber close to the door panel side, and ratchet teeth are arranged in the groove, and the ratchet teeth slide in cooperation with the groove, and a spring is arranged between the ratchet teeth and the groove, and both ends of the spring are fixedly connected to the ratchet teeth and the groove respectively; the material chamber is filled with liquid reducing agent, and the material chamber is connected with the recovery chamber through the valve core.

[0010] The basic scheme principles and beneficial effects are as follows:

[0011] As the temperature of the active layer changes, the water in the active layer near the deep-buried pile enters the heat release chamber through the air holes with the air before freezing. The iron in the heat release chamber contacts with the water and oxygen in the air to produce an exothermic reaction. After a series of exothermic reactions, the iron eventually generates iron oxide. The working medium in the telescopic airbag expands after being heated, pushing the flip door open and squeezing the generated iron oxide into the recovery chamber. The iron column on the telescopic airbag passes through the partition and presses against the valve core. The liquid reducing agent in the material chamber will enter the recovery chamber and reduce the iron oxide to iron. At this time, the heat release of the iron ends, and the telescopic airbag will shrink until the water before the active layer freezes next time enters the air holes and repeats the above reaction with the iron.

[0012] As the liquid reducing agent is continuously consumed, the door panel close to the air chamber will slowly move toward the air chamber (the distance between air molecules in the air chamber is large, and the distance between liquid reducing agent molecules in the material chamber is small. Under the same cold shrinkage pressure, gas molecules are easier to get close to each other and thus easier to be compressed). When the door panel passes through the ratchet teeth, the ratchet teeth are squeezed into the groove. After the door panel passes through the ratchet teeth, the spring restores its deformation and resets the ratchet teeth.

[0013] This solution combines iron with liquid water in the active layer and oxygen in the air to produce an exothermic reaction, which consumes and evaporates the water near the deep buried piles, keeps the roadbed near the deep buried piles dry, thereby reducing its moisture content and reducing the freeze-thaw effect of the active layer, thereby improving the stability of the deep buried piles.

[0014] This solution allows the iron element to be reused by arranging a reducing agent in the material box, thereby extending the service life of the deep buried pile.

[0015] This solution sets a valve core between the material chamber and the recovery chamber, and uses the principle of thermal expansion and contraction to control the start of the valve core, so that the liquid reducing agent can reduce the oxidized iron element in time after the iron element is oxidized, avoiding the inability to continuously release heat to the nearby roadbed after the iron element is completely oxidized.

[0016] This solution utilizes the different molecular distances between gas and liquid, and the air chamber is easier to squeeze than the material chamber. As a result, after the reducing agent in the material chamber is consumed, the door plate can pass over the valve core to achieve autonomous replenishment of the material reducing agent; at the same time, when the door plate passes over the valve core, the door plate will temporarily block the valve core to achieve regulation of the release dose of the reducing agent.

[0017] In summary, the adoption of this scheme can reduce the moisture content of the roadbed near the deep buried piles, keep the roadbed dry, and thus improve the stability of the deep buried piles.

[0018] Furthermore, the working medium includes but is not limited to liquid ammonia; the liquid reducing agent includes but is not limited to sulfite.

[0019] Furthermore, a heat-insulating pile is fixedly connected to the bottom of the deep-buried pile.

[0020] Beneficial effect: The heat-insulating pile can isolate the heat in the heat release chamber, thereby preventing the heat in the heat release chamber from affecting the structure of the permafrost layer, causing the permafrost layer to melt, and thus causing the sinking of the pipe pile.

[0021] Furthermore, the bottom of the thermal insulation pile is conical.

[0022] Beneficial effect: It is easy to insert the insulation piles into the permafrost layer.

[0023] A construction method for a railway contact network pipe pile freeze-thaw deformation prevention and control structure in a frozen soil area comprises the following steps:

[0024] Step 1: Construction survey: measure the span, elevation, and turning angle according to the route and pile positions proposed in the design drawing, and level the land near the roadbed;

[0025] Step 2: Pile position measurement. Using the principle of "from the whole to the part", the pile positions on the design drawings are accurately measured to the pile sinking area and marked according to the design and construction requirements;

[0026] Step 3: Equipment installation and commissioning: install the pile hammer and other pile driving equipment at the predetermined location, and fix and commission them;

[0027] Step 4: Drilling: First, drill the hole with a preset hole depth by using a drilling rig. After the hole depth reaches the preset hole depth, remove the drill bit, and then perform hot air drying on the pile hole; then continue drilling to the permafrost layer;

[0028] Step 5: Pile sinking: After the drill bit is removed, the permafrost at the bottom of the pile hole is pre-thawed with hot air, and the deep buried piles and insulation piles that have been welded in advance are sunk into the pile hole together by a crane;

[0029] Step 6: Pile driving: use a pile hammer to hammer the deep buried pile until the insulation pile is inserted into the permafrost layer;

[0030] Step 7: Welding the box, welding the material box to the top of the deep buried pile;

[0031] Step 8: Connect the piles. Use a crane to align the welded piles with the deep buried piles and weld them to the top of the material box. After acceptance, the construction is completed.

[0032] Furthermore, in step 4, when drilling, the pile hole diameter is 5-10 cm larger than the pile diameter, wherein the pile diameters of the deep buried piles, welded piles and insulation piles are all the same.

[0033] Furthermore, in step five, before pile sinking, impurities in the pile hole are cleaned.

[0034] Furthermore, in step five, during the pile sinking process, the verticality of the deep buried pile is monitored in real time by a theodolite. If the deviation of the verticality exceeds a preset deviation threshold, the deep buried pile is lifted and corrected and then sunk back into the borehole.

[0035] Further, the preset deviation threshold is 0.5% of the total pile length of the deep buried pile and the insulation pile.

[0036] Furthermore, in step five, dry fine sand is simultaneously filled into the gap between the drill hole and the deep buried pile during pile sinking.

[0037] The basic scheme principles and beneficial effects are as follows:

[0038] 1. This scheme conducts heat drying treatment on the pile hole. After the soil in the side wall of the pile hole is dried, the moisture content of the soil will be greatly reduced, thereby reducing the freeze-thaw effect of the roadbed near the pile hole.

[0039] 2. This solution improves the stability of the insulation piles and avoids the adverse effects of freeze-thaw on the insulation piles by hammering the insulation piles into the permafrost layer, which is stable all year round and will not experience freeze-thaw effects.

[0040] 3. This scheme sets the pile hole diameter to be 5-10cm larger than the pile diameter during drilling, so as to correct the verticality of the deep buried pile when the verticality does not meet the standard.

[0041] 4. This solution fills the gap between the deep pile and the pile hole with dry fine sand. When the dry fine sand is subjected to frost heave, the extrusion load on the deep pile and the insulation pile is more uniform, which can avoid the deep pile and the insulation pile from breaking due to frost heave. In addition, the dry fine sand is relatively coarse, which can reduce the upward pull force caused by frost heave. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 Schematic diagram of the arrangement of embodiment 1 of the present invention

[0043] Figure 2 Schematic diagram of the internal structure of Example 1 of the present invention.

[0044] Figure 3 for Figure 2 A partial enlarged view of area A.

[0045] Figure 4 for Figure 2 Schematic diagram of the structure of the middle partition.

[0046] Figure 5 The present invention is a schematic diagram of a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas.

[0047] Figure 6 The present invention is a flow chart of a construction method of a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas. DETAILED DESCRIPTION

[0048] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0049] In the description of the present invention, it is necessary to understand that the terms "longitudinal", "lateral", "vertical", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying 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 operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0050] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection between two components. 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 can be understood according to the specific circumstances.

[0051] The following is further described in detail through specific implementation methods:

[0052] The figure marks in the drawings of the specification include: welding pile 1, deep buried pile 2, material box 3, partition 4, insulation pile 5, recovery chamber 201, heat release chamber 202, valve core 2011, air vent 2021, telescopic air bag 2022, iron column 2023, iron element 2024, door panel 301, material chamber 302, air chamber 303, ratchet teeth 304, smooth cushion layer 305, flip door 401, groove 3041, spring 3042.

[0053] Example

[0054] The embodiment is basically as shown in the attached Figure 1-6 As shown:

[0055] A freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas, comprising: deep buried piles and welded piles;

[0056] A heat release chamber and a recovery chamber are arranged inside the deep buried pile, and the heat release chamber is located below the recovery chamber; a telescopic airbag is arranged at the bottom of the heat release chamber, and the telescopic airbag is fixed with the heat release chamber by buckle, and an iron column is threadedly connected in the middle of the telescopic airbag (in this embodiment, a threaded flange is arranged in the middle of the telescopic airbag, and for the sake of ease of understanding, the threaded flange and the telescopic airbag are referred to as the telescopic airbag) and the telescopic airbag is filled with a working medium; the area above the telescopic airbag in the heat release chamber is filled with iron element (specifically, a pure iron sheet); a plurality of air holes are opened on the side of the heat release chamber; a valve core is welded in the middle of the top of the recovery chamber, and a partition is welded between the recovery chamber and the heat release chamber; a plurality of flip doors are arranged on the partition (in this embodiment, there are 4 flip doors), and the flip doors are hinged to the partition;

[0057] The welding pile is located above the deep buried pile, and a material box is arranged at the bottom of the welding pile, and the top and bottom of the material box are respectively welded and fixed to the welding pile and the deep buried pile; smooth cushion layers are bonded on all sides of the inside of the material box; an air chamber and a material chamber are arranged in the material box, and a number of door panels are arranged in the material chamber, and the door panels slide in cooperation with the material box, and the door panels divide the material chamber into a number of small material chambers; the air chamber and the material chamber are separated by door panels; a groove is arranged in the air chamber close to the door panel side, and ratchet teeth are arranged in the groove, and the ratchet teeth slide in cooperation with the groove, and a spring is arranged between the ratchet teeth and the groove, and both ends of the spring are respectively welded to the ratchet teeth and the groove; the material chamber is filled with liquid reducing agent, and the material chamber is connected with the recovery chamber through the valve core.

[0058] The working medium includes but is not limited to liquid ammonia, and the liquid reducing agent includes but is not limited to sulfite; a heat-insulating pile is welded to the bottom of the deep-buried pile, and the bottom of the heat-insulating pile is conical.

[0059] The specific implementation process is as follows:

[0060] For example, as the weather in frozen areas changes periodically, the active layer within 80 cm around the deep buried piles and insulation piles (such as the surrounding Figure 1 , 2 As shown, the upper layer is the active layer, and the lower layer is the permafrost layer, the same below) liquid water (liquid water comes from rainfall and natural water in the active layer before freezing) penetrates into the heat release chamber through the air vents, and at the same time, oxygen in the air also enters the heat release chamber through the air vents, and the iron in the heat release chamber reacts with oxygen and water to generate iron oxide after a series of reactions. The heat released consumes and evaporates the nearby water, and at the same time, the liquid ammonia in the telescopic airbag expands due to heat, and the liquid ammonia changes from liquid to gas, which expands the telescopic airbag. The iron column in the middle of the telescopic airbag pushes the flip door open as the telescopic airbag expands, and then the iron column and the iron oxide are pushed into the recovery chamber until the iron column presses against the valve core. The valve core is pressed, and the material chamber is connected with the recovery chamber. At this time, the liquid reducing agent in the material chamber enters the recovery chamber through the valve core, and the liquid reducing agent enters the recovery chamber to react with the iron oxide, reducing the iron oxide to the iron.

[0061] During the process of the telescopic airbag expanding due to heat, the air bag will gradually block the air holes, and the external oxygen and water will be temporarily isolated. At this time, the exothermic reaction between the iron element and water and oxygen will stop, and the generated heat will be scattered into the active layer near the deeply buried piles, evaporating the water in the active layer and greatly reducing the water content of the active layer; after cooling, the telescopic air bag retracts to the bottom of the heat release chamber until the next rainfall, when the rainwater penetrates into the active layer and the above process is repeated.

[0062] During the consumption of the liquid reducing agent, the air chamber and the material chamber are cooled and contracted, and the gas will be compressed faster because the distance between gas molecules is larger. When the same pressure is applied, the gas molecules are easier to get close to each other and thus easier to be compressed. The air in the air chamber is cooled and squeezed, and the leftmost door panel (such as the attached Figure 1 , 2 As shown in the figure, the same below) will slowly move to the left until the leftmost door panel passes through the ratchet teeth, and the ratchet teeth are squeezed into the groove. After the door panel passes through the ratchet teeth smoothly, the ratchet teeth pop out from the groove and reset; when it expands due to heat, due to the restriction of the ratchet teeth, the door panel passes through the ratchet teeth in one direction. Therefore, as the liquid reducing agent is continuously consumed, all the door panels will move to one side of the air chamber one by one. During the movement of the door panels, the door panels will pass through the valve core one after another and briefly close the valve core until the door panel completely passes over the valve core, and the valve core connects the material chamber and the recovery chamber.

[0063] Example 2

[0064] The only difference from the above embodiment is that Figure 6 As shown, a construction method for a freeze-thaw deformation prevention and control structure of railway contact network pipe piles in frozen soil areas is also provided, comprising the following steps:

[0065] Step 1: Construction survey: measure the span, elevation, and turning angle according to the route and pile positions proposed in the design drawing, and level the land near the roadbed;

[0066] Specifically, through field surveys and investigations, the location and size of the construction are determined, and the distribution, bearing capacity and other relevant parameters of the soil layer near the roadbed are understood. According to the survey results, a suitable construction plan is formulated, and the required construction equipment and materials are prepared. Then, the debris and obstacles beside the existing roadbed are cleared by mechanical equipment such as excavators and graders to ensure the flatness of the construction area. At the same time, the existing roadbed is reinforced or improved according to the design plan. This may include widening the roadbed, adding drainage facilities, and reinforcing slopes. These works are aimed at improving the stability and bearing capacity of the roadbed and ensuring the smooth progress of subsequent construction.

[0067] Step 2: Pile position measurement. Using the principle of "from the whole to the part", the pile positions on the design drawings are accurately measured to the pile sinking area and marked according to the design and construction requirements;

[0068] Step 3: Equipment installation and commissioning: install the pile hammer and other pile driving equipment at the predetermined location, and fix and commission them;

[0069] Step 4: Drilling: First, drill the hole with a preset hole depth by using a drilling rig. After the hole depth reaches the preset hole depth, remove the drill bit, and then perform hot air drying on the pile hole; then continue drilling to the permafrost layer;

[0070] When drilling, the pile hole diameter is 5-10cm larger than the pile diameter, and the pile diameters of deep buried piles, welded piles and insulation piles are the same;

[0071] Step 5: Pile sinking. After taking out the drill bit, before sinking the pile, clean the impurities in the pile hole (such as sediment, ice, water accumulation, etc.), and then use a crane to sink the pre-welded deep-buried pile and insulation pile into the pile hole together. While sinking the pile, fill the gap between the drill hole and the deep-buried pile with dry fine sand. During the pile sinking process, the verticality of the deep-buried pile is monitored in real time by the theodolite. If the deviation of the verticality exceeds the preset deviation threshold (the preset deviation threshold is 0.5% of the total pile length of the deep-buried pile and the insulation pile, that is, if the total pile length is 20 meters, the preset deviation threshold is 10mm), the deep-buried pile is lifted and corrected and then sunk into the borehole again. Special attention should be paid to the impact on the roadbed to ensure that the roadbed will not be damaged during the pile sinking process.

[0072] Step 6: Pile driving: use a pile hammer to hammer the deep buried piles and insert the insulation piles into the permafrost layer;

[0073] When hammering, control the frequency and strength of the pile hammer, for example, use a low-lift hammer method with a frequency of 20 times / min.

[0074] Step 7: Welding the box, weld the material box to the top of the deep buried pile; (When welding, use low current welding to avoid as much as possible: the strength of the concrete joint is affected by the excessively high welding temperature, the same below).

[0075] Step 8: Connect the piles. Use a crane to align the welded piles with the deep buried piles and weld them to the top of the material box. After acceptance, the construction is completed.

[0076] The above is only an embodiment of the present invention, and the common knowledge such as the known specific structure and / or characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the present invention, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A freeze-thaw deformation prevention and control structure for railway contact network piles in frozen soil areas, characterized by: include: Deep buried piles and welded piles; A heat release chamber and a recovery chamber are arranged inside the deep buried pile, and the heat release chamber is located below the recovery chamber; a telescopic airbag is fixedly connected to the bottom of the heat release chamber, an iron column is fixedly connected in the middle of the telescopic airbag, and a working medium is contained in the telescopic airbag; the top of the telescopic airbag in the heat release chamber is filled with iron; a plurality of air holes are arranged on the side of the heat release chamber; a valve core is arranged in the middle of the top of the recovery chamber, a partition is arranged between the recovery chamber and the heat release chamber, and the partition is fixedly connected to the deep buried pile; a plurality of flip doors are arranged on the partition, and the flip doors are all rotatably connected to the partition; The welding pile is located above the deep buried pile, and a material box is arranged at the bottom of the welding pile, and the top and bottom of the material box are fixedly connected to the welding pile and the deep buried pile respectively; smooth cushion layers are fixedly connected on all sides inside the material box; an air chamber and a material chamber are arranged in the material box, and a number of door panels are arranged in the material chamber, and the door panels slide in cooperation with the material box, and the door panels divide the material chamber into a number of small material chambers; the air chamber and the material chamber are separated by door panels; a groove is arranged in the air chamber close to the door panel side, and ratchet teeth are arranged in the groove, and the ratchet teeth slide in cooperation with the groove, and a spring is arranged between the ratchet teeth and the groove, and both ends of the spring are fixedly connected to the ratchet teeth and the groove respectively; the material chamber is filled with liquid reducing agent, and the material chamber is connected with the recovery chamber through the valve core.

2. The freeze-thaw deformation prevention and control structure for railway contact network piles in frozen soil areas according to claim 1, characterized in that: The working medium is liquid ammonia; the liquid reducing agent is sulfite.

3. The freeze-thaw deformation prevention and control structure for railway contact network piles in frozen soil areas according to claim 1, characterized in that: The bottom of the deep buried pile is also fixedly connected with a heat insulation pile.

4. The freeze-thaw deformation prevention and control structure for railway contact network piles in frozen soil areas according to claim 3, characterized in that: The bottom of the insulation pile is conical.

5. A construction method for a frozen soil region railway contact network pipe pile freeze-thaw deformation prevention and control structure, based on the frozen soil region railway contact network pipe pile freeze-thaw deformation prevention and control structure according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: Construction survey: measure the span, elevation, and turning angle according to the route and pile positions proposed in the design drawing, and level the land near the roadbed; Step 2: Pile position measurement. Using the principle of "from the whole to the part", the pile positions on the design drawings are accurately measured to the pile sinking area and marked according to the design and construction requirements; Step 3: Installation and commissioning of the pile driver: install the pile driver and other pile driving equipment at the predetermined location, and fix and commission them; Step 4: Drilling: First, drill the hole with a preset hole depth by using a drilling rig. After the hole depth reaches the preset hole depth, remove the drill bit, and then perform hot air drying on the pile hole; then continue drilling to the permafrost layer; Step 5: Pile sinking: After the drill bit is removed, the permafrost at the bottom of the pile hole is pre-thawed with hot air, and the deep buried piles and insulation piles that have been welded in advance are sunk into the pile hole together by a crane; Step 6: Pile driving: use a pile hammer to hammer the deep buried pile until the insulation pile is inserted into the permafrost layer; Step 7: Welding the box, welding the material box to the top of the deep buried pile; Step 8: Connect the piles. Use a crane to align the welded piles with the deep buried piles and weld them to the top of the material box. After acceptance, the construction is completed.

6. The method for constructing a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas according to claim 5, characterized in that: In step 4, when drilling, the pile hole diameter is 5-10 cm larger than the pile diameter, wherein the pile diameters of deep buried piles, welded piles and insulation piles are all the same.

7. The method for constructing a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas according to claim 6, characterized in that: In step five, before sinking the pile, the impurities in the pile hole are cleaned.

8. The method for constructing a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas according to claim 6, characterized in that: In step five, during the pile sinking process, the verticality of the deep buried pile is monitored in real time. If the deviation of the verticality exceeds the preset deviation threshold, the deep buried pile is lifted and corrected and then sunk back into the borehole.

9. The method for constructing a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas according to claim 8, characterized in that: The preset deviation threshold is 0.5% of the total pile length for deep buried piles and thermal insulation piles.

10. The method for constructing a freeze-thaw deformation prevention and control structure for railway contact network pipe piles in frozen soil areas according to claim 6, characterized in that: In step five, dry fine sand is filled into the gap between the drill hole and the deep buried pile when sinking the pile.

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