Construction process and foundation structure for constructing prestressed concrete pipe pile in low-temperature laboratory

Abstract

The invention relates to the field of building construction, in particular to a prestressed concrete pipe pile construction technology and a foundation structure for low-temperature laboratory construction. The method comprises the steps of determining a pile end bearing layer, clearing away obstacles on a site, setting protective measures, testing the pile to obtain parameters, stacking tubular piles, sinking the pile by adopting a hammering or static pressure method and monitoring the pile in real time, re-pressing the condition of exceeding a threshold value, welding and connecting tubular pile sections, and detecting and accepting. The structure further comprises a foundation structure, a pipe pile body is arranged in a foundation in a pile sinking mode, an uplift pile is fixed in the pipe pile through micro-expansion concrete, and at least three steel bars with bottom plates are arranged in the uplift pile. The technical effects that it is guaranteed that the construction process of the prestressed concrete pipe pile in the low-temperature laboratory is standard, safe and efficient, the stability and the pulling resistance of the pipe pile foundation structure are improved, and the construction quality and building safety are guaranteed are achieved.

Description

Technical Field

[0001] This application relates to the field of building construction, and in particular to the construction technology and foundation structure of prestressed concrete pipe piles for the construction of low-temperature laboratories. Background Technology

[0002] In the field of construction engineering, pile foundation construction is a crucial step in ensuring the stability and safety of buildings. With the continuous development of the construction industry, the demand for various special buildings is increasing, such as cryogenic laboratories. Cryogenic laboratories have extremely high requirements for the stability and durability of the foundation, as the low-temperature environment can have additional effects on the building structure, such as material shrinkage and freeze-thaw cycles. Prestressed concrete pipe piles, with their significant advantages such as high bearing capacity, high construction efficiency, and good economy, have been widely used in pile foundation construction for various building projects, including cryogenic laboratory construction. They provide a solid and stable foundation support for building structures, driving the construction industry towards higher quality and higher efficiency. In cryogenic laboratory construction, prestressed concrete pipe piles can better adapt to complex geological conditions and special usage requirements. They can not only meet the bearing requirements of cryogenic laboratories of different sizes and types, but also shorten the construction period and reduce costs to a certain extent, playing an important role in the smooth progress and sustainable development of cryogenic laboratory construction projects.

[0003] In traditional prestressed concrete pipe pile construction, a series of conventional methods are typically employed to address related construction issues. Regarding the construction process, a systematic and standardized operating procedure is lacking; the operational requirements for each construction stage are not standardized, and construction workers often rely on experience. The definition of key construction parameters is also unclear, such as pile driving sequence, hammer blow count, and pile splicing techniques, lacking precise data guidance and leading to considerable arbitrariness during construction. The selection of pile body parameters often fails to closely align with actual construction requirements, making it difficult to develop a standardized construction guidance plan. Furthermore, during construction, there are often no comprehensive control measures for issues such as soil squeezing and pile displacement. In addition, most existing construction specifications are only general guidelines, lacking specific construction instructions for particular bearing strata (such as completely weathered granite and strongly weathered granite), and these specifications are not organically integrated, making implementation extremely difficult for construction workers. In the construction of low-temperature laboratories, these conventional methods do not fully consider the impact of low-temperature environments on construction, such as the effects of low temperatures on concrete setting time and pile material properties.

[0004] However, these existing technologies have significant drawbacks. The lack of systematic and standardized construction processes, vague definitions of key construction parameters, and a disconnect between pile parameters and construction requirements lead to inconsistent construction quality. In the construction of cryogenic laboratories, this instability can cause foundation problems in low-temperature environments, affecting the normal operation of the laboratory. Furthermore, inadequate measures to control soil displacement and pile misalignment severely impact the safety and durability of the pile foundation project. In addition, the lack of specific construction instructions for particular bearing layers and insufficient integration of construction specifications increase the difficulty of operational execution during construction, further affecting construction efficiency and quality. In the construction of cryogenic laboratories, these problems can lead to extended construction periods, increased costs, and may even prevent the fulfillment of the specific requirements for foundation stability and durability in cryogenic laboratories. Summary of the Invention

[0005] The purpose of this application is to overcome the above-mentioned technical problems and to provide the construction process and foundation structure of prestressed concrete pipe piles for the construction of low-temperature laboratories.

[0006] The construction process of prestressed concrete pipe piles for low-temperature laboratory construction includes the following steps: S1: Determine that the bearing stratum at the pile tip is a completely weathered or strongly weathered granite layer; S2: Clear obstacles from the construction site and adjacent areas; S3: When piling work affects adjacent buildings, vibration damping structures or soil compression reduction structures shall be installed as protective measures. S4: Obtain pile driving construction parameters by performing non-engineering pile test piles; S5: Stacking the pipe pile body, the stacking includes single layer or stacked layer. When stacking, wooden blocks are placed about 1 / 5 of the length of the pipe pile at the pile end along the length of the pipe pile and the outer edge of the pipe pile is fixed. S6: Use hammer driving or static pressure driving method to drive piles, and monitor the pile's uplift and deviation in real time during the driving process; S7: When the upward float exceeds a predetermined threshold or the deviation exceeds the allowable range, a static pressure pile driver is used for re-pressurization; S8: Connect the pipe pile segments by welding, control the misalignment of the pipe pile segments, and perform multi-layer and multi-pass welding and natural cooling on the weld. S9: Inspection and acceptance include acceptance of pile verticality, plane position and elevation, and execution of single pile bearing capacity test and pile integrity test.

[0007] By adopting the above technical solution, the concrete pipe pile construction process covers six core parts: construction preparation, pipe pile arrival inspection and stacking, pile driving operation, pile splicing and cutting, and inspection and acceptance. It clarifies the operation procedures, technical parameters, deviation control, and safety requirements for each step. Specifically, determining the bearing stratum at the pile tip allows for construction targeting specific bearing strata; clearing obstacles ensures smooth construction; setting up protective measures reduces the impact on adjacent buildings; obtaining pile driving parameters through test piles provides a basis for subsequent construction; reasonable stacking of pipe piles avoids damage and tilting; real-time monitoring of pile floating and deviation, and re-pressurization ensures the pile is vertical and accurately driven to the design depth; welding and connecting pipe pile segments and controlling deviations, as well as treating weld seams, ensure connection quality; and inspection and acceptance verify construction quality. This construction method has clear steps, well-defined parameters, and strong operability. Through the coordinated optimization of each step, it effectively solves many technical pain points in existing pipe pile construction, improving construction quality, safety, efficiency, and pile durability while expanding its applicability and reducing construction costs.

[0008] Preferably, the predetermined threshold is 5 mm, and the allowable range is no more than 0.5%.

[0009] By adopting the above technical solution, the specific control standards for pile body uplift and deviation are clarified, which can promptly detect abnormalities in the pile body, facilitate the use of static pressure pile drivers for re-pressure correction, ensure that the pile body is vertical and accurately sinks into the design depth, and guarantee the quality of pile foundation construction.

[0010] Preferably, the shock-absorbing structure includes a shock-absorbing trench, the depth of which is 2 to 3 meters.

[0011] By adopting the above technical solutions, the depth of the anti-vibration trench in the vibration reduction structure is determined to be 2 to 3 meters, ensuring that the vibration reduction effect meets the standards, avoiding protection failure due to improper parameters, further improving the reliability of protection, reducing the impact of pile driving vibration on adjacent buildings, protecting adjacent buildings, and improving construction safety and standardization.

[0012] Preferably, the soil-displacement-reducing structure is a driven anti-displacement steel sheet pile.

[0013] By adopting the above technical solutions, a specific and operable protection method is provided for the soil squeezing effect caused by pile driving. When encountering corresponding problems, timely action can be taken to reduce the construction impact caused by the soil squeezing effect, further protect adjacent buildings, and improve construction safety and standardization. By clearly defining the specific structure of anti-soil squeezing steel sheet piles, it is possible to ensure that the soil squeezing reduction effect meets the standards, avoid protection failure due to improper parameters, ensure the stability of the soil squeezing reduction structure, and improve the reliability of protection.

[0014] Preferably, when stacking the wooden blocks, the cross-sectional height of the blocks is greater than the outer diameter of the pipe pile.

[0015] By adopting the above technical solutions, the force on the pipe piles can be more uniform during stacking, avoiding deformation and damage to the pile body due to differences in the outer diameter and stress performance of the pipe piles, further protecting the pipe pile body and improving the safety and rationality of stacking.

[0016] Preferably, when using the hammer driving method for pile driving, a hammer pad is provided between the pile hammer and the pile cap, and an elastic liner is provided between the pile cap and the pipe pile.

[0017] By adopting the above technical solutions, the hammer pad and elastic liner can reduce the impact damage to the pile body and protect the pipe pile body. Combined with the steps of determining the bearing layer at the pile end, clearing the site, setting up protective measures, obtaining pile driving parameters, stacking pipe piles, pile driving monitoring, re-pressurization, welding pipe pile segments, and testing and acceptance, the quality and efficiency of the entire prestressed concrete pipe pile construction process for the construction of the low temperature laboratory can be improved.

[0018] Preferably, the verticality deviation of the first section of the pipe pile is controlled within 0.5% during the hammer driving method.

[0019] By adopting the above technical solution, the verticality deviation of the first section of the pipe pile can be controlled within 0.5% during the hammer driving method, which can prevent the subsequent pile body from tilting continuously, improve the pile driving accuracy, and adapt to the construction scenario of dense pipe piles.

[0020] Preferably, when using the static pressure method for pile driving, the foundation of the site should be reinforced before construction to ensure that its bearing capacity is sufficient.

[0021] By adopting the above technical solutions, when using static pressure pile driving in the construction of prestressed concrete pipe piles in low-temperature laboratories, the ground foundation can be reinforced before construction to avoid ground settlement during construction, which would affect the pile driving accuracy, ensure the stability of static pressure construction, ensure that the pile can be accurately driven into the design depth, and further improve the quality and reliability of static pressure pile driving.

[0022] The prestressed concrete pipe pile foundation structure uses the above-mentioned low-temperature laboratory construction process for prestressed concrete pipe piles, including a foundation, in which pipe pile bodies are installed by driving piles, and anti-tension piles are fixedly installed inside the pipe pile bodies by micro-expansion concrete.

[0023] By adopting the above technical solutions, the pull-out resistance of the pipe pile foundation is enhanced, the vertical bearing stability is improved, and the overall integrity of the foundation structure is optimized, thus solving the shortcomings of ordinary prestressed concrete pipe piles in pull-out scenarios.

[0024] Preferably, the anti-tension pile has at least three steel bars inside, and the bottom end of the steel bars is fixedly provided with a base plate.

[0025] By adopting the above technical solution, an anti-tension pile is set inside the pipe pile body. The anti-tension pile is equipped with at least three steel bars and the bottom end of the steel bars is fixedly set with a base plate. This can enhance the anti-tension performance of the pipe pile foundation, improve the vertical bearing stability, optimize the overall structure of the foundation, and solve the shortcomings of ordinary prestressed concrete pipe piles in anti-tension scenarios.

[0026] In summary, this application includes at least one of the following beneficial technical effects: 1. This concrete pipe pile construction process encompasses six core parts: construction preparation, pipe pile arrival inspection and stacking, pile driving operation, pile splicing and cutting, and testing and acceptance. It clearly defines the operational procedures, technical parameters, deviation control, and safety requirements for each stage. Specifically, determining the bearing stratum allows for targeted construction; clearing obstacles ensures smooth construction; setting up protective measures reduces the impact on adjacent buildings; obtaining pile driving parameters through test piles provides a basis for subsequent construction; proper stacking of pipe piles avoids damage and tilting; real-time monitoring of pile floating and deviation, along with re-pressurization, ensures the pile is vertical and accurately driven to the design depth; welding and connecting pipe pile segments and controlling deviations, as well as treating weld seams, ensure connection quality; and testing and acceptance verify construction quality. This construction method features clear steps, well-defined parameters, and strong operability. Through the coordinated optimization of each stage, it effectively solves many technical pain points in existing pipe pile construction, improving construction quality, safety, efficiency, and pile durability while expanding its applicability and reducing construction costs. 2. The specific control standards for pile body uplift and deviation were clarified, which can promptly detect abnormalities in the pile body, facilitate the use of static pressure pile drivers for re-pressure correction, ensure that the pile body is vertical and accurately sinks into the design depth, and guarantee the quality of pile foundation construction; 3. Specific and operable protective measures have been developed to address the soil displacement effect caused by pile driving. These measures can be implemented promptly when problems arise, reducing the construction impact of soil displacement, further protecting adjacent buildings, and improving construction safety and standardization. The specific structure of anti-soil displacement steel sheet piles ensures that the soil displacement reduction effect meets the standards, avoids protection failure due to improper parameters, guarantees the stability of the soil displacement reduction structure, and improves the reliability of protection. 4. In the construction of prestressed concrete pipe piles in the low-temperature laboratory, when the static pressure method is used for pile driving, the foundation of the site is reinforced before construction to avoid site settlement during construction, which would affect the pile driving accuracy, ensure the stability of the static pressure method construction, ensure that the pile body can be accurately driven into the design depth, and further improve the quality and reliability of static pressure pile driving. 5. Setting up tension piles inside the pipe pile body, with at least three reinforcing bars inside each tension pile and a base plate fixed at the bottom of the reinforcing bars, can enhance the tension resistance of the pipe pile foundation, improve the vertical bearing stability, optimize the overall structure of the foundation, and solve the shortcomings of ordinary prestressed concrete pipe piles in tension scenarios. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the connection structure between the tension pile and the pipe pile body in this application; Figure 2 This is a cross-sectional view of the connection between the tension pile and the pipe pile body in this application. Figure 3 This is a schematic diagram of the segmental connection structure of the pipe pile body in this application.

[0028] The components include: 1. Foundation; 2. Pipe pile body; 3. Tension pile; 4. Micro-expansion concrete; 5. Base slab. Detailed Implementation

[0029] The technical solutions in the embodiments of this application will be further described in detail below with reference to the accompanying drawings. The described embodiments are only possible technical implementations of this application, but are not limited thereto. Other embodiments obtained by those skilled in the art in conjunction with the embodiments of this application without creative effort are also within the protection scope of this application.

[0030] This application mainly adopts a prestressed concrete pipe pile construction technology with clearly defined construction procedures and parameters, which achieves the effect of improving the construction quality and efficiency of pipe piles in low-temperature laboratories. The following is in conjunction with the appendix... Figure 1-3 A further detailed description of this application. Example 1

[0031] The prestressed concrete pipe pile construction process for low-temperature laboratory construction provided in this application includes steps such as construction preparation, pipe pile stacking, pile driving, pile splicing, and testing and acceptance. Each step is closely linked and works in coordination, which achieves the effects of standardizing the construction process, improving construction quality, and reducing the impact of construction on the surrounding area. This is because each step has clear operational requirements and parameter standards, which can effectively avoid arbitrariness and uncertainty in construction.

[0032] Specifically, the construction preparation steps include determining the bearing stratum at the pile tip, clearing the site, setting up protective measures, and obtaining pile driving parameters. When determining the bearing stratum, it is specified as a completely weathered or strongly weathered granite layer, determined based on the geological requirements of the low-temperature laboratory and the bearing capacity requirements of the pipe piles. Clearing obstacles from the construction site and adjacent areas provides a good working environment for subsequent construction. When pile driving operations affect nearby buildings, vibration-damping structures or soil-displacement-reducing structures are installed as protective measures. Vibration-damping structures can be excavated anti-vibration trenches, 2 to 3 meters deep and 1 to 1.5 meters wide, filled with graded sand and gravel as a buffer layer with a thickness of 0.5 to 0.8 meters; soil-displacement-reducing structures can be driven anti-displacement steel sheet piles with an insertion depth of not less than 1.2 meters. These protective measures effectively reduce the impact of pile driving on surrounding buildings. Pile driving parameters, such as pile driving speed, hammer force or pile driving force, and verticality control standards, are obtained by performing non-engineering pile test piles. These parameters provide accurate basis for subsequent pile driving operations.

[0033] During the pipe pile stacking process, the pipe pile body 2 is stacked in a single layer or in multiple layers, depending on the site bearing capacity and space conditions. When stacking in multiple layers, wooden blocks are placed approximately 1 / 5 of the pile length from the pile tip to secure the outer edge of the pipe pile. The cross-sectional height of the wooden blocks is greater than the outer diameter of the pipe pile. For example, for pipe piles with an outer diameter of 500-600mm, the cross-sectional height of the wooden blocks can be set to the outer diameter of the pipe pile plus 20mm. This ensures the stability of the stacked pipe piles and prevents damage.

[0034] The pile driving operation involves either hammer driving or static pressure driving. When using hammer driving, a hammer pad with a Shore A60-A80 hardness is placed between the hammer and the pile cap, and an elastic liner is placed between the pile cap and the pipe pile. The verticality deviation of the first section of the pipe pile is controlled within 0.5%. The pile driving sequence proceeds from the center outwards. When the spacing between pipe piles is less than 3.5 times the outer diameter of the pipe pile, a skip-driving method with a spacing of not less than 2 times the outer diameter of the pipe pile is used. The hammer pad and elastic liner reduce impact damage to the pile body and protect the pipe pile body. Controlling the verticality of the first section of the pipe pile prevents subsequent piles from tilting continuously. A reasonable pile driving sequence and skip-driving method can weaken the soil squeezing effect and avoid mutual interference between pipe piles. When using the static pressure method for pile driving, the site foundation must be reinforced before construction to ensure its bearing capacity characteristic value is not less than 120 kPa, the maximum pile driving force is controlled to be not less than twice the characteristic value of the vertical bearing capacity of a single pile, and the clamping force is not greater than 1.1 times the allowable lateral pressure of the pile body. Multiple re-pressing operations are performed during final pressing, the number of re-pressing operations determined according to the pile length, with each re-pressing time being 3-5 seconds. Site foundation reinforcement can prevent site settlement during construction, which would affect pile driving accuracy; limiting the pile driving force and clamping force can prevent pile damage and ensure the structural integrity of the pile; the final pressing and re-pressing standards can ensure that the pile reaches the design elevation and meets the bearing capacity requirements. During pile driving, the pile's uplift and deviation are monitored in real time. When the pile's uplift exceeds 5 mm or the deviation exceeds 0.5%, a static pressure pile driver is used for re-pressing. The re-pressing force is 1.2-1.5 times the characteristic value of the vertical bearing capacity of a single pile, and the re-pressing is performed 2-3 times.

[0035] The pile splicing process involves connecting pipe pile segments using welding. During welding, the misalignment deviation between upper and lower pile segments should not exceed 2mm. Symmetrical multi-layer, multi-pass welding is employed, with at least two welding layers. Post-weld natural cooling time should be at least 5 minutes, and quality control of the weld is implemented. In corrosive environments, pile joints located in corrosive soil layers undergo anti-corrosion treatment. The inspection and acceptance process involves verifying the verticality, planar position, and elevation of the piles after pile driving; recording data from the pile driving process; and conducting static load tests on single pile bearing capacity and pile integrity inspections. The number of single pile bearing capacity static load tests should be at least 1% of the total number of piles and at least 3 piles, with the maximum load not less than twice the characteristic value of the single pile bearing capacity. Pile integrity inspections utilize the low-strain method, with at least 20% of the total number of piles tested and at least 10 piles tested. When using the low-strain method, the signal acquisition time should be at least 20ms, and the signal amplitude resolution should not exceed 1mV. For quality defects discovered during inspection, remedial measures such as pile replacement or pile replacement are taken. The center distance between the replacement pile and the original pile position is not less than 1.5 times the outer diameter of the pipe pile. The implementation principle of this embodiment is as follows: This construction process organically combines steps such as construction preparation, pipe pile stacking, pile driving, pile splicing, and inspection and acceptance by clearly defining the operation procedures, technical parameters, and deviation control requirements for each construction stage, forming a systematic and comprehensive construction plan. The specific parameters and operation requirements for each step are designed to ensure construction quality, reduce the impact of construction on the surrounding environment, and improve construction efficiency. Compared with existing technologies, this process solves problems such as non-standard construction, ambiguous definition of key parameters, and inadequate prevention and control measures. It can effectively improve the construction quality and safety of prestressed concrete pipe piles in low-temperature laboratory construction, reduce construction costs, and expand the scope of application. Example 2

[0036] The difference between this embodiment and the previous embodiment lies in the following: In pile driving operations, when using the hammer driving method, in addition to setting a hammer pad between the pile hammer and the pile cap, and an elastic liner between the pile cap and the pipe pile, new types of cushioning materials can be used to replace the hammer pad and elastic liner, such as polymer rubber materials or fiber composite materials. These new materials have better cushioning and wear resistance, which can further reduce pile impact damage and extend the service life of the pile and construction equipment. Furthermore, regarding the pile driving sequence, in addition to driving from the center outwards and skip-driving methods, a zoned pile driving method can be adopted according to specific site conditions and pipe pile layout. That is, the construction area is first divided into several small areas, and then pile driving operations are carried out sequentially in each small area. This allows for more flexible responses to different construction scenarios and improves construction efficiency.

[0037] The implementation principle of this embodiment is as follows: by adopting new buffer materials and a more flexible pile driving sequence, the construction process of hammer pile driving is further optimized. The use of new buffer materials can better protect the pile body and construction equipment, reducing maintenance and replacement costs; the zoned pile driving method can reasonably arrange the construction sequence according to the actual situation, avoid mutual interference between pipe piles, improve construction efficiency and quality, and further enhance the adaptability and creativity of the entire construction process. Example 3

[0038] The prestressed concrete pipe pile foundation structure provided in this application includes a foundation 1, in which a pipe pile body 2 is installed by driving the piles using a hammer method or a static pressure method. Inside the pipe pile body 2, an anti-tension pile 3 is fixedly installed by micro-expansion concrete 4. At least three steel bars are installed inside the anti-tension pile 3, and a base plate 5 is fixedly installed at the bottom end of the steel bars.

[0039] Foundation 1 is the load-bearing foundation of the entire foundation structure, and its geological conditions and bearing capacity are crucial to the stability of the pipe pile foundation. Before construction, foundation 1 needs to be thoroughly surveyed and treated to ensure it meets construction requirements. The pipe pile body 2 is accurately placed inside foundation 1 through pile driving operations, providing vertical bearing capacity for the foundation structure. The micro-expansion concrete 4 generates a certain expansion force during the solidification process, which enables the tension pile 3 to be tightly bonded to the pipe pile body 2, improving the anchoring effect of the tension pile 3. The steel reinforcement inside the tension pile 3 enhances its tensile strength, while the base plate 5 increases the contact area between the tension pile 3 and foundation 1, improving the tension resistance of the tension pile 3.

[0040] The implementation principle of this embodiment is as follows: This foundation structure combines the aforementioned prestressed concrete pipe pile construction technology for cryogenic laboratory construction. The pipe pile body 2 provides vertical bearing capacity, while the tension pile 3 provides tensile strength. The two work together to improve the stability and durability of the foundation structure. The inclusion of micro-expansion concrete 4, reinforcing steel, and the base slab 5 further optimizes the performance of the tension pile 3, enabling it to better meet the special requirements of cryogenic laboratories. Compared with traditional foundation structures, this structure effectively solves the shortcomings of ordinary prestressed concrete pipe piles in tensile scenarios, improving the safety and reliability of the entire foundation structure and providing a solid foundation guarantee for the construction of cryogenic laboratories.

[0041] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. Construction technology of prestressed concrete pipe piles for low-temperature laboratory construction, characterized in that, Includes the following steps: S1: Determine that the bearing stratum at the pile tip is a completely weathered or strongly weathered granite layer; S2: Clear obstacles from the construction site and adjacent areas; S3: When piling work affects adjacent buildings, vibration damping structures or soil compression reduction structures shall be installed as protective measures. S4: Obtain pile driving construction parameters by performing non-engineering pile test piles; S5: Stacking the pipe pile body (2), the stacking includes single layer or stacked layer. When stacking, a wooden block is set at about 1 / 5 of the length of the pipe pile at the pile end in the length direction of the pipe pile and the outer edge of the pipe pile is fixed. S6: Use hammer driving or static pressure driving method to drive piles, and monitor the pile's uplift and deviation in real time during the driving process; S7: When the upward float exceeds a predetermined threshold or the deviation exceeds the allowable range, a static pressure pile driver is used for re-pressurization; S8: Connect the pipe pile segments by welding, control the misalignment of the pipe pile segments, and perform multi-layer and multi-pass welding and natural cooling on the weld. S9: Inspection and acceptance include acceptance of pile verticality, plane position and elevation, and execution of single pile bearing capacity test and pile integrity test.

2. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 1, characterized in that, The predetermined threshold is 5 mm, and the allowable range is no more than 0.5%.

3. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 1 or 2, characterized in that, The shock-absorbing structure includes a shock-absorbing trench with a depth of 2 to 3 meters.

4. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 1 or 2, characterized in that, The soil compression reduction structure is a driven anti-displacement steel sheet pile.

5. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 1, characterized in that, When stacked, the cross-sectional height of the padding timber is greater than the outer diameter of the pipe pile.

6. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 1, characterized in that, When using the hammer driving method for pile driving, a hammer pad is placed between the pile hammer and the pile cap, and an elastic liner is placed between the pile cap and the pipe pile.

7. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 6, characterized in that, When driving piles using the hammer method, the verticality deviation of the first section of the pipe pile is controlled within 0.5%.

8. The construction technology of prestressed concrete pipe piles for low-temperature laboratory construction according to claim 1, characterized in that, When using the static pressure method for pile driving, the foundation of the site should be reinforced before construction to ensure that its bearing capacity is sufficient.

9. A prestressed concrete pipe pile foundation structure, using the prestressed concrete pipe pile construction technology for low-temperature laboratory construction as described in any one of claims 1-8, including a foundation (1), characterized in that: The foundation (1) contains a pipe pile body (2) installed inside by hammer driving or static pressure driving, and the pipe pile body (2) contains an anti-pull pile (3) fixed inside by micro-expansion concrete (4).

10. The prestressed concrete pipe pile foundation structure according to claim 9, characterized in that, The anti-tension pile (3) is provided with at least three steel bars inside, and the bottom end of the steel bars is fixedly provided with a base plate (5).

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