Prestressed high-strength concrete pipe pile static pressure sinking structure and construction method

Abstract

The application discloses a prestressed high-strength concrete pipe pile static pressure sinking structure and a construction method, and belongs to the technical field of pipe pile construction. The application comprises a base, one side of the base is fixedly connected with an adjusting mechanism, the other side of the base is fixedly connected with a limiting mechanism, a hydraulic mechanism is arranged between the adjusting mechanism and the limiting mechanism, the bottom of the hydraulic mechanism is fixedly connected with a rotating mechanism, the bottom of the rotating mechanism is fixedly connected with a connecting mechanism, and the bottom of the connecting mechanism is provided with a pile body. The adjusting mechanism comprises a fixing frame, the top of the fixing frame is fixedly connected with a first motor, the output end of the first motor is fixedly connected with a threaded rod, and the surface of the threaded rod is threadedly connected with a threaded sleeve. The limiting mechanism comprises a limiting frame, the inner wall of the limiting frame is fixedly connected with a sliding rod, and the surface of the sliding rod is slidingly connected with a sliding sleeve. Through cooperation of the intelligent monitoring and regulation system and the innovative pile-soil interaction optimization technology, the problems of difficult effective control of the soil squeezing effect and high risk of the pile body floating and deviating are solved.

Description

Technical Field

[0001] This invention relates to the field of pipe pile construction technology, specifically to a prestressed high-strength concrete pipe pile static pressure driving structure and construction method. Background Technology

[0002] With the vigorous development of modern construction engineering, higher and higher requirements have been put forward for the stability and bearing capacity of foundation engineering. Prestressed high-strength concrete pipe piles have been widely used in the construction of various building foundations due to their high strength, good durability and convenient construction. Static pressure pile driving has also become one of the common construction methods due to its relatively low noise and vibration impact. For a long time in the past, the traditional prestressed high-strength concrete pipe pile static pressure pile driving structure and construction method laid the foundation for many construction projects.

[0003] However, in practical engineering applications, especially in the face of increasingly complex building environments and diverse geological conditions, the limitations of traditional methods have gradually become apparent. On the one hand, in complex soil foundation areas, such as soft soil layers, saturated cohesive soil, sites with deep sand layers or uneven soil texture, the soil squeezing effect during the pipe pile driving process becomes a thorny problem. Due to the incompressibility of the soil and the soil squeezing characteristics of the pipe pile, the soil around the pile shifts significantly, and the pore water pressure changes abruptly, often leading to serious consequences such as ground heave, settlement and cracking of surrounding buildings, and damage to underground pipelines, posing a huge threat to project safety and the surrounding environment. On the other hand, the phenomenon of pile floating and deviating occurs frequently, which is particularly prominent in soft soil foundations. During the construction process, ultra-long prestressed pipe piles are prone to deviating, floating, or even breaking due to the lateral displacement of the soil around the pile and their own stability issues, which greatly affects the bearing capacity of the pile foundation and the stability of the overall structure, increasing potential quality hazards and subsequent repair costs.

[0004] In addition to the aforementioned quality and safety issues, traditional construction methods also face challenges in terms of construction efficiency and cost control. The significant sidewall resistance during pile driving requires the pile driver to consume more energy to overcome the resistance, resulting in slower pile driving speeds and extended construction periods. This not only increases the rental costs of machinery and equipment and fuel consumption but may also lead to additional indirect costs due to project delays. Furthermore, when encountering underground pile breaks, traditional handling methods are often complex, time-consuming, and labor-intensive, making it difficult to guarantee the quality of pile splicing. This often requires substantial manpower, material resources, and financial resources for repair or reconstruction, further exacerbating the increase in construction costs and significantly reducing the economic benefits of the project. There is an urgent need for an innovative structure and construction method to break this deadlock and achieve a balanced development of efficient, high-quality, and economical foundation construction. Summary of the Invention

[0005] The purpose of this invention is to provide a prestressed high-strength concrete pipe pile static pressure driving structure and construction method. Through the combination of intelligent monitoring and control system and innovative pile-soil interaction optimization technology, the problems of difficult soil squeezing effect and high risk of pile body floating and deflection in the prior art are solved.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A prestressed high-strength concrete pipe pile static pressure driving structure includes a base, an adjustment mechanism fixedly connected to one side of the base, a limiting mechanism fixedly connected to the other side of the base, a hydraulic mechanism between the adjustment mechanism and the limiting mechanism, a rotating mechanism fixedly connected to the bottom of the hydraulic mechanism, a connecting mechanism fixedly connected to the bottom of the rotating mechanism, and a pile body disposed at the bottom of the connecting mechanism; the adjustment mechanism includes a fixed frame, a first motor fixedly connected to the top of the fixed frame, a threaded rod fixedly connected to the output end of the first motor, a threaded sleeve threadedly connected to the surface of the threaded rod; the limiting mechanism includes a limiting frame, a sliding rod fixedly connected to the inner wall of the limiting frame, and a sliding sleeve slidably connected to the surface of the sliding rod;

[0008] The hydraulic mechanism includes two vertical plates, which are respectively fixedly connected to the surfaces of a threaded sleeve and a sliding sleeve. A horizontal plate is fixedly connected between the vertical plates, and a first hydraulic telescopic rod is passed through the top of the horizontal plate. The rotating mechanism includes a housing, the top of which is fixedly connected to the output end of the first hydraulic telescopic rod. A second motor is fixedly connected to one side of the bottom of the housing, and a first gear is fixedly connected to the output end of the second motor. A vertical rod is movably connected to the bottom of the housing via a bearing, and a second gear is fixedly connected to the top of the vertical rod. The first gear and the second gear mesh. The connecting mechanism includes a connecting plate. The connecting plate is fixed to the bottom of the vertical rod, and a connecting sleeve is fixedly connected to the bottom of the connecting plate. A snap-fit ​​plate is fixedly connected to the inner wall of the connecting sleeve. The top of the pile extends into the inner cavity of the connecting sleeve. An insert plate is fixedly connected to the bottom of the snap-fit ​​plate. A slot for cooperating with the insert plate is opened on the top of the pile. Support plates are fixedly connected to both sides of the connecting sleeve. A second hydraulic telescopic rod is provided through the surface of the support plate. A movable plate is fixedly connected to the output end of the second hydraulic telescopic rod. A fixing block is fixedly connected to the opposite side of the movable plate. Fixing grooves for cooperating with the fixing blocks are opened on the top of both sides of the pile.

[0009] Furthermore, both sides of the top of the base are fixedly connected with mating grooves, and a counterweight block is provided in the inner cavity of the counterweight groove.

[0010] Furthermore, both sides of the base are fixedly connected to a fixing plate, a pin is provided through the top of the fixing plate, and a through hole is opened on the top of the fixing plate to cooperate with the pin.

[0011] A construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure includes the following steps:

[0012] Step 1, Geological Survey: Using advanced geological exploration equipment, a combination of high-precision ground-penetrating radar and deep drilling, a comprehensive, detailed and in-depth survey of the construction site is conducted to accurately determine the thickness, type, distribution range of each soil layer, as well as the physical and mechanical parameters of each soil layer, including but not limited to internal friction angle, cohesion, and compression modulus. The depth of the groundwater level and its changes with seasonal and climatic factors are also recorded in detail.

[0013] Step 2, Pile Material Inspection: Based on relevant national standards and strict design requirements, comprehensive and high-precision quality control is implemented for prestressed high-strength concrete pipe piles. At the same time, the sealing, connection firmness and force transmission performance of the pile joints are tested. Through tests simulating actual stress conditions, the reliability and stability of the joints under design loads are verified to ensure that they meet the requirements of construction and long-term use.

[0014] Step 3: Equipment commissioning: Conduct comprehensive, in-depth and meticulous commissioning and inspection of the static pressure pile driver to ensure that all systems of the pile driver operate stably and reliably during construction, providing a solid guarantee for the smooth progress of pile driving operations;

[0015] Step 4: Rationally plan the pile driving sequence: Taking into account the topography, geological conditions and surrounding environmental factors of the construction site, the entire construction area is scientifically divided into several small areas of moderate size and regular shape. In each small area, the construction is carried out by combining zoned pile driving and skip driving, so that the soil has enough time to adjust stress and consolidate during the process of the pile 7 entering the soil, thereby effectively reducing the risk of soil squeezing effect and pile body floating and deviating.

[0016] Step 5: Control the pile driving speed. During the pile driving process, the pile driving speed shall be strictly controlled according to the geological survey report and the actual site conditions. At the same time, the pile driving speed shall be dynamically adjusted according to the pile penetration depth and the sensitivity of the surrounding environment. In soft soil areas, due to the special mechanical properties of the soil, in order to prevent problems such as excessive soil deformation caused by the untimely dissipation of pore water pressure, the number of piles completed per day shall be strictly controlled not to exceed 3, and the cumulative number of consecutive pile driving days in the same area shall not exceed 5 days, so as to ensure the stability of the soil and the quality of the pile body during the construction process.

[0017] Step Six: Set up anti-squeezing trenches and drainage facilities: Around the pile driving area, anti-squeezing trenches should be set up reasonably according to the geological conditions of the site and the distribution of surrounding buildings and underground pipelines. The depth of the anti-squeezing trenches should be determined to be 1.6-2.0m and the width should be 0.7-0.9m. Mechanical excavation combined with manual trimming should be used for construction to ensure the flatness and stability of the trench walls, so that they can effectively release soil stress, block the stress transmission path caused by soil squeezing, and protect the surrounding facilities from the impact of soil squeezing. At the same time, sand wells or plastic drainage boards should be set up in the pile foundation construction area at certain intervals and layouts.

[0018] Step 7: Set up isolation piles and monitoring measures: Around the affected buildings or underground facilities, select and set up isolation measures such as pile banks, jet grouting piles, anti-seepage walls, or concrete underground continuous walls, according to their structural type, foundation form and distance from the pile driving area. During the pile driving process, use high-precision total stations and levels to monitor the first piles driven in real time and continuously, with a monitoring frequency of no less than once every 20 minutes, to keep track of the pile's uplift and tilt.

[0019] Step 8: Pre-drilling to reduce resistance: At the pile location, use professional drilling equipment to perform pre-drilling operations. The drilling diameter is determined based on the pile diameter and should be 60-100mm smaller than the pile diameter. The drilling depth is reasonably determined based on the pile length and geological conditions, and should be within the range of 1 / 3-1 / 2 of the pile length. That is, for a 30m long pile, the drilling depth should be controlled between 10-15m. During the drilling process, strictly control the verticality deviation of the drilling to not exceed 0.4% to ensure the concentricity of the drilling and the pile location.

[0020] Step 9: Apply lubricant to the pile body: Apply a specially developed high-efficiency lubricant evenly to the surface of the pile body, with the thickness controlled between 2-3mm. This ensures that a stable lubricating film can be formed at the pile-soil interface during the pile driving process, effectively reducing the friction coefficient between the pile and the soil. During the application process, an automated spraying equipment combined with manual assistance is used to ensure the uniformity and integrity of the lubricant application, avoiding missed areas or uneven thickness, thereby fully leveraging its role in reducing sidewall resistance and improving the smoothness and efficiency of pile driving.

[0021] Step 10: Optimize pile tip design: Based on detailed geological survey data of the construction site, and in combination with the characteristics of the pile type and design requirements, conduct targeted optimization design of the pile tip;

[0022] Step 11, Underground Pile Splicing Construction: When an underground pile breaks during construction, construction should be immediately suspended and the broken pile area should be thoroughly inspected and evaluated. First, using a combination of manual labor and small machinery, carefully clean the soil, debris, and loose concrete fragments around the broken pile area to ensure that the broken pile section is clearly visible and free of residual impurities. Then, use professional grinding tools to finely grind the connection area of ​​the broken pile to make its surface smooth and the roughness meet the design requirements. Use a high-pressure water gun to thoroughly clean the connection surface to remove surface dust and oil, ensuring the cleanliness and adhesion of the connection surface. Next, select appropriate special pile splicing connectors to ensure that the weld is full, uniform, and free of porosity and crack defects. After the connection is completed, conduct a visual inspection and dimensional verification of the connection area to ensure that the quality of the pile splicing meets the relevant standards and design requirements.

[0023] Step Twelve, Quality Inspection and Acceptance: After the underground pile splicing construction is completed, non-destructive testing should be carried out on the splicing area in a timely manner. When using ultrasonic testing technology, the testing probes should be arranged according to relevant standards and specifications to comprehensively scan the weld or connection area. The testing frequency should not be lower than 1.2MHz. By analyzing the reflected wave signals of the ultrasonic waves, it is determined whether there are any defects inside the splicing area to ensure the internal quality of the splice. At the same time, a low-strain testing method is used to measure the stress wave propagation of the pile body by applying impact force to the pile top to further verify the integrity of the splicing area. The pile length range of the test should cover the entire splicing area and a certain length of the pile body above and below to ensure that the splicing area is well connected to the original pile body and has strong integrity. In addition, after completing a certain number of pile foundation constructions, according to In accordance with design requirements and relevant specifications, static load tests or high-strain tests are conducted on the entire pile foundation. Static load tests employ a step-by-step loading method, with the load amount determined as a multiple of the design load. During loading, high-precision displacement and pressure sensors are used to monitor the settlement and load changes at the pile top in real time, generating load-settlement curves. Based on the curve characteristics and relevant standards, the bearing capacity of the pile foundation is determined to meet design requirements. High-strain tests involve applying transient impact force to the pile top and using strain gauges and accelerometers to measure the strain and acceleration response of the pile body. By analyzing these response data, the integrity and bearing capacity of the pile foundation are evaluated, ensuring that the quality and stability of the entire pile foundation meet engineering design and usage requirements, providing a solid and reliable foundation for subsequent construction.

[0024] Furthermore, in step one, these data are systematically analyzed and organized using professional geological analysis software to draw geological profile maps and related parameter charts accurate to the millimeter level, providing detailed and reliable geological basis for the formulation of subsequent construction plans.

[0025] Furthermore, in step two, advanced ultrasonic testing equipment and total station equipment are used to perform non-destructive testing on the strength of the pile body to ensure that it reaches the design strength level and the strength distribution is uniform, with the strength deviation controlled within ±3% of the design strength; the dimensions of the pile body are accurately measured, including diameter, wall thickness, and length; and professional verticality testing tools are used to ensure that the verticality of the pile body meets the specifications, with a deviation not exceeding one-thousandth of the pile length.

[0026] Furthermore, in step three, for the hydraulic system, high-precision pressure sensors and flow meters are used to check whether the pressure and flow of the hydraulic oil are stable and meet the working requirements of the pile driver. The sealing and operational flexibility of each hydraulic component, such as the oil pump, oil cylinder, and control valve, are tested to ensure that there are no leaks or jamming. The pressure gauge is calibrated with high precision to control its measurement error within a very small range so as to accurately reflect the pressure changes during the pile driving process. The verticality control system is precisely adjusted using a laser calibration device and an electronic level to ensure that the pile driver can automatically adjust the verticality of the pile in real time during the pile driving process, keeping it within the allowable deviation range.

[0027] Furthermore, in step six, the sand wells use circular steel pipes with a diameter of 0.4m as the well walls, filled with well-graded medium-coarse sand as filter material, arranged at intervals of 1.6-2.0m in a quincunx pattern, with a depth of about 10m. Two or three rows are set around the pile driving area to further reduce the adverse effects of soil squeezing on the soil and pile body by accelerating the dissipation of pore water pressure.

[0028] Furthermore, during construction in step eight, a drilling-as-you-go approach is adopted, meaning that pile driving is carried out immediately after drilling is completed. This allows the pile to sink in a relatively loose soil environment, effectively reducing the friction between the pile sidewall and the soil, significantly improving pile driving efficiency, and reducing construction difficulty and energy consumption.

[0029] Furthermore, in step ten, for geological conditions where the upper layer is a relatively soft soil layer and the lower layer is a relatively hard soil layer, a conical pile tip is used. The cone angle is determined between 40° and 60° based on the mechanical properties of the soil layer and the pile diameter. The length of the pile tip is 1.2 to 2.0 times the pile diameter. Through the soil squeezing and breaking action of the conical pile tip, the pile body can more easily penetrate the upper soft soil layer and enter the lower hard soil layer. For cases where the strata are relatively uniform and hard, a flat-bottomed pile tip is selected, and an appropriate cutting edge is set on the edge of the pile tip. The cutting edge angle is 25° to 45° and the width is 15 to 30 mm to enhance the cutting ability and soil penetration performance of the pile tip, reduce the resistance of the soil to the pile tip, and improve the pile driving efficiency and the stability of the pile body.

[0030] Compared with the prior art, the beneficial effects of the present invention are:

[0031] In terms of construction quality and efficiency, this invention ensures reliable pile quality, with standardized factory production guaranteeing its stability. The pile driving force is accurately read with minimal human interference, and the static pressure method allows for fast construction speed, flexible pile configuration, and convenient extension, effectively shortening the construction period. In terms of environment and safety, it is vibration-free, low-noise, and environmentally friendly, making it suitable for areas with high environmental requirements. At the same time, the construction stress is low and easy to control, with a high degree of mechanization and simple operation, reducing the risk of pile quality problems and the probability of safety accidents. Attached Figure Description

[0032] Figure 1 This is a three-dimensional structural view of the present invention;

[0033] Figure 2 This is a perspective view of the base and related structures of the present invention;

[0034] Figure 3 This is a perspective view of the limiting mechanism of the present invention;

[0035] Figure 4 This is a sectional perspective view of the rotating mechanism and the connecting mechanism of the present invention;

[0036] Figure 5 This is a perspective view of the hydraulic mechanism of the present invention;

[0037] Figure 6 This is a perspective view of the adjustment mechanism of the present invention;

[0038] Figure 7 This is a flowchart illustrating the construction process of the present invention.

[0039] In the diagram: 1. Base; 2. Adjustment mechanism; 3. Limiting mechanism; 4. Hydraulic mechanism; 5. Rotating mechanism; 6. Connecting mechanism; 7. Pile body; 201. Fixing frame; 202. First motor; 203. Threaded rod; 204. Threaded sleeve; 301. Limiting frame; 302. Sliding rod; 303. Sliding sleeve; 401. Vertical plate; 402. Horizontal plate; 403. First hydraulic telescopic rod; 501. Box body; 502. Second motor; 503. First gear; 504. Vertical rod; 505. Second gear; 601. Connecting plate; 602. Connecting sleeve; 603. Snap-fit ​​plate; 604. Insert plate; 605. Support plate; 606. Second hydraulic telescopic rod; 607. Moving plate; 608. Fixing block. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] Please see Figure 1-7 This embodiment provides the following technical solution: a prestressed high-strength concrete pipe pile static pressure driving structure, including a base 1, an adjustment mechanism 2 fixedly connected to one side of the base 1, a limiting mechanism 3 fixedly connected to the other side of the base 1, a hydraulic mechanism 4 provided between the adjustment mechanism 2 and the limiting mechanism 3, a rotating mechanism 5 fixedly connected to the bottom of the hydraulic mechanism 4, a connecting mechanism 6 fixedly connected to the bottom of the rotating mechanism 5, and a pile body 7 provided at the bottom of the connecting mechanism 6; the adjustment mechanism 2 includes a fixing frame 201, a first motor 202 fixedly connected to the top of the fixing frame 201, and a threaded rod 203 fixedly connected to the output end of the first motor 202. The surface of the 3-axis threaded connection is provided with a threaded sleeve 204. The limiting mechanism 3 includes a limiting frame 301, with a sliding rod 302 fixedly connected to the inner wall of the limiting frame 301, and a sliding sleeve 303 slidably connected to the surface of the sliding rod 302. The hydraulic mechanism 4 includes a vertical plate 401, with two vertical plates 401 fixedly connected to the surfaces of the threaded sleeve 204 and the sliding sleeve 303 respectively. A horizontal plate 402 is fixedly connected between the vertical plates 401, and a first hydraulic telescopic rod 403 is provided through the top of the horizontal plate 402. The rotating mechanism 5 includes a housing 501, with the top of the housing 501 fixedly connected to the output end of the first hydraulic telescopic rod 403, and a second hydraulic telescopic rod 403 fixedly connected to one side of the bottom of the inner cavity of the housing 501. Motor 502, the output end of the second motor 502 is fixedly connected to the first gear 503, the bottom of the housing 501 is movably connected to the vertical rod 504 through the bearing, the top of the vertical rod 504 is fixedly connected to the second gear 505, the first gear 503 and the second gear 505 mesh, the connecting mechanism 6 includes a connecting plate 601, the connecting plate 601 is fixed to the bottom of the vertical rod 504, the bottom of the connecting plate 601 is fixedly connected to the connecting sleeve 602, the inner wall of the connecting sleeve 602 is fixedly connected to the snap-fit ​​plate 603, the top of the pile body 7 extends into the inner cavity of the connecting sleeve 602, the bottom of the snap-fit ​​plate 603 is fixedly connected to the insert plate 604, the top of the pile body 7 is provided with a... The slot used in conjunction with the insert plate 604, the connecting sleeve 602, and the support plates 605 are fixedly connected to both sides. The surface of the support plate 605 is provided with a second hydraulic telescopic rod 606. The output end of the second hydraulic telescopic rod 606 is fixedly connected to a moving plate 607. The opposite side of the moving plate 607 is fixedly connected to a fixing block 608. The top of both sides of the pile body 7 is provided with fixing grooves that cooperate with the fixing blocks 608. The top of both sides of the base 1 is fixedly connected with mating grooves. The counterweight groove is provided with a counterweight block. The base 1 is fixedly connected with both sides of the base. The top of the fixing plate is provided with a pin. The top of the fixing plate is provided with a through hole for cooperating with the pin.

[0042] The first motor 202 is started, which drives the threaded rod 203 to rotate. The threaded rod 203 drives the threaded sleeve 204 to move downward. The inner cavity of the fixed frame 201 has a moving groove, and a moving block is slidably connected to the inner wall of the moving groove. The moving groove and the moving block can limit the threaded sleeve 204, improving the stability of the threaded sleeve 204 when moving up and down. The threaded sleeve 204 drives the hydraulic mechanism 4 to move up and down, realizing the adjustment of the working height of the hydraulic mechanism 4. When the hydraulic mechanism 4 moves downward, it drives the sliding sleeve 303 to move up and down. The sliding sleeve 303, in conjunction with the sliding rod 302, improves the stability of the pressing mechanism when moving up and down. The user inserts the top of the pile 7 into the inner cavity of the connecting sleeve 602, activates the second hydraulic telescopic rod 606, and the second hydraulic telescopic rod 606 drives the moving plate 607 to move. The moving plate 607 drives the fixing block 608 to insert into the fixing groove. The fixing block 608, together with the fixing groove and the moving plate 607, fixes the pile 7. The user then activates the first hydraulic telescopic rod 403, which drives the pile 7 to press down through the rotating mechanism 5 and the connecting mechanism 6. During the pressing process, the user can activate the second motor 502, which drives the pile 7 to rotate through the connecting mechanism 6, thus achieving the purpose of rotating and pressing down.

[0043] A construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure includes the following steps:

[0044] Step a: Geological Survey: Using advanced geological exploration equipment, a combination of high-precision ground-penetrating radar and deep drilling, a comprehensive, detailed, and in-depth survey of the construction site is conducted. The thickness, type, distribution range, and physical and mechanical parameters of each soil layer are accurately measured, including but not limited to internal friction angle, cohesion, and compression modulus. The depth of the groundwater level and its variation with seasonal and climatic factors are recorded in detail. These data are systematically analyzed and organized using professional geological analysis software to draw geological profile maps and related parameter charts accurate to the millimeter level, providing detailed and reliable geological basis for the formulation of subsequent construction plans.

[0045] Step b: Pile Material Inspection: Based on relevant national standards and stringent design requirements, comprehensive and high-precision quality control is implemented for prestressed high-strength concrete pipe piles. Simultaneously, the joints of the piles are tested for sealing, connection firmness, and force transmission performance. Through tests simulating actual stress conditions, the reliability and stability of the joints under design loads are verified to ensure they meet construction and long-term use requirements. Advanced ultrasonic testing equipment and total station equipment are used for non-destructive testing of the pile body's strength to ensure it reaches the design strength grade and has uniform strength distribution, with strength deviation controlled within ±3% of the design strength. The dimensions of the pile body are accurately measured, including diameter, wall thickness, and length. Professional verticality testing tools are used to ensure the verticality of the pile body meets the specifications, with a deviation not exceeding one-thousandth of the pile length.

[0046] Step c: Equipment Commissioning: Conduct comprehensive, in-depth, and meticulous commissioning and inspection of the static pressure pile driver to ensure stable operation and reliable performance of all systems during construction, providing a solid guarantee for the smooth progress of pile driving. For the hydraulic system, use high-precision pressure sensors and flow meters to check whether the pressure and flow of the hydraulic oil are stable and meet the working requirements of the pile driver. Test the sealing and operational flexibility of each hydraulic component, such as oil pumps, cylinders, and control valves, to ensure no leakage or jamming. Perform high-precision calibration of the pressure gauges to control their measurement error within a very small range, so as to accurately reflect the pressure changes during the pile driving process. Use laser calibration devices and electronic levels to precisely adjust the verticality control system to ensure that the pile driver can automatically adjust the verticality of the pile in real time during the pile driving process, keeping it within the allowable deviation range.

[0047] Step d: Rationally plan the pile driving sequence: Taking into account the topography, geological conditions and surrounding environmental factors of the construction site, the entire construction area is scientifically divided into several small areas with moderate size and regular shape. In each small area, the construction is carried out by combining zoned pile driving and skip driving, so that the soil has enough time to adjust stress and consolidate during the process of the pile 7 entering the soil, thereby effectively reducing the risk of soil squeezing effect and pile body floating and deviating.

[0048] Step e: Control the pile driving speed: During the pile driving process, the pile driving speed is strictly controlled according to the geological survey report and the actual site conditions. At the same time, the pile driving speed is dynamically adjusted according to the pile penetration depth and the sensitivity of the surrounding environment. In soft soil areas, due to the special mechanical properties of the soil, in order to prevent problems such as excessive soil deformation caused by the untimely dissipation of pore water pressure, the number of piles completed per day is strictly controlled not to exceed 3, and the cumulative number of consecutive pile driving days in the same area shall not exceed 5 days, so as to ensure the stability of the soil and the quality of the pile body during the construction process.

[0049] Step f: Setting up anti-squeezing trenches and drainage facilities: Around the pile driving area, anti-squeezing trenches are reasonably set up according to the geological conditions of the site and the distribution of surrounding buildings and underground pipelines. The depth of the anti-squeezing trenches is determined to be 1.6-2.0m and the width is 0.7-0.9m. The construction is carried out by mechanical excavation combined with manual trimming to ensure the flatness and stability of the trench walls, so that they can effectively release soil stress, block the stress transmission path generated by soil squeezing, and protect the surrounding facilities from the impact of soil squeezing. At the same time, in the pile foundation construction area, sand wells or plastic drainage boards are set up at certain intervals and layouts. The sand wells use circular steel pipes with a diameter of 0.4m as the well walls and fill them with well-graded medium and coarse sand as filter material. The spacing is 1.6-2.0m, arranged in a quincunx pattern, and the depth reaches about 10m. Two or three rows are set up around the pile driving area to further reduce the adverse effects of soil squeezing on the soil and pile body by accelerating the dissipation of pore water pressure.

[0050] Step g: Setting up isolation piles and monitoring measures: Around the affected buildings or underground facilities, based on their structural type, foundation form and distance from the pile driving area, reasonably select and set up isolation measures such as pile rows, jet grouting piles, or seepage prevention walls, concrete underground continuous walls, etc. During the pile driving process, use high-precision total stations and levels to monitor the first driven piles in real time and continuously, with a monitoring frequency of no less than once every 20 minutes, to promptly grasp the pile's uplift and tilt.

[0051] Step h: Pre-drilling to reduce resistance: At the pile location, pre-drilling is carried out using professional drilling equipment. The drilling diameter is determined based on the pile diameter and should be 60-100mm smaller than the pile diameter. The drilling depth is reasonably determined based on the pile length and geological conditions, and should be within the range of 1 / 3-1 / 2 of the pile length. That is, for a 30m long pile, the drilling depth should be controlled between 10-15m. During the drilling process, the verticality deviation of the drilling should be strictly controlled to not exceed 0.4%, ensuring the concentricity of the drilling and the pile location. During construction, the method of drilling and driving is adopted, that is, the pile driving operation is carried out immediately after the drilling is completed, so that the pile body can sink in a relatively loose soil environment, effectively reducing the friction between the pile sidewall and the soil, significantly improving the pile driving efficiency, and reducing the construction difficulty and energy consumption.

[0052] Step i: Applying lubricant to the pile body: Apply a specially developed high-efficiency lubricant evenly to the surface of the pile body, with the thickness controlled between 2-3mm. This ensures that a stable lubricating film can be formed at the pile-soil interface during the pile driving process, effectively reducing the friction coefficient between the pile and the soil. During the application process, an automated spraying equipment combined with manual assistance is used to ensure the uniformity and integrity of the lubricant application, avoiding missed areas or uneven thickness, thereby fully leveraging its role in reducing side wall resistance and improving the smoothness and efficiency of pile driving.

[0053] Step j: Optimize pile tip design: Based on detailed geological survey data of the construction site, and combined with the characteristics of the pile type and design requirements, the pile tip is optimized accordingly. For geological conditions where the upper layer is a relatively soft soil layer and the lower layer is a relatively hard soil layer, a conical pile tip is adopted. The cone angle is determined between 40° and 60° according to the mechanical properties of the soil layer and the pile diameter. The length of the pile tip is 1.2 to 2.0 times the pile diameter. Through the soil squeezing and breaking action of the conical pile tip, the pile body can more easily penetrate the upper soft soil layer and enter the lower hard soil layer. For cases where the strata are relatively uniform and hard, a flat-bottomed pile tip is selected, and an appropriate cutting edge is set on the edge of the pile tip. The cutting edge angle is 25°-45° and the width is 15-30mm to enhance the cutting ability and soil penetration performance of the pile tip, reduce the resistance of the soil to the pile tip, and improve the pile driving efficiency and the stability of the pile body.

[0054] Step k: Underground pile splicing construction: When an underground pile breaks during construction, construction should be immediately suspended and the broken pile area should be thoroughly inspected and evaluated. First, using a combination of manual labor and small machinery, the soil, debris, and loose concrete fragments around the broken pile area should be carefully cleaned to ensure that the broken pile section is clearly visible and free of residual impurities. Then, using professional grinding tools, the connection area of ​​the broken pile should be finely ground to make its surface smooth and the roughness meet the design requirements. The connection surface should be thoroughly cleaned with a high-pressure water gun to remove surface dust and oil stains, ensuring the cleanliness and adhesion of the connection surface. Next, appropriate special pile splicing connectors should be selected to ensure that the weld is full, uniform, and free of porosity and crack defects. After the connection is completed, the connection area should be visually inspected and its dimensions checked to ensure that the quality of the pile splicing meets the relevant standards and design requirements.

[0055] Step 1: Quality Inspection and Acceptance: After the underground pile splicing construction is completed, non-destructive testing should be carried out on the splicing area in a timely manner. When using ultrasonic testing technology, the testing probes should be arranged according to relevant standards and specifications to comprehensively scan the weld or connection area. The testing frequency should not be lower than 1.2MHz. By analyzing the reflected wave signals of the ultrasonic waves, it is determined whether there are any internal defects in the splicing area to ensure the internal quality of the splice. At the same time, a low-strain testing method is used to apply impact force to the pile top and measure the stress wave propagation of the pile body to further verify the integrity of the splicing area. The pile length range of the test should cover the entire splicing area and a certain length of the pile body above and below to ensure that the splicing area is well connected to the original pile body and has strong integrity. In addition, after completing a certain number of pile foundation constructions, the splicing area should be inspected according to the design specifications. In accordance with design requirements and relevant specifications, static load tests or high-strain tests are conducted on the entire pile foundation. Static load tests employ a step-by-step loading method, with the load amount determined based on a multiple of the design load. During loading, high-precision displacement and pressure sensors are used to monitor the settlement and load changes at the pile top in real time, generating load-settlement curves. Based on the curve characteristics and relevant standards, the bearing capacity of the pile foundation is determined to meet design requirements. High-strain tests involve applying transient impact force to the pile top and using strain gauges and accelerometers to measure the strain and acceleration response of the pile body. By analyzing these response data, the integrity and bearing capacity of the pile foundation are evaluated, ensuring that the quality and stability of the entire pile foundation meet engineering design and usage requirements, providing a solid and reliable foundation for subsequent engineering construction.

[0056] Foundation construction of urban commercial complex

[0057] Project Overview: This commercial complex is located in a bustling urban area with dense surrounding buildings and complex underground pipelines. The geological conditions consist of soft plastic silty clay at the top 5-8 meters and medium-dense to dense sandy silt at the bottom. The groundwater level is high and varies significantly with the seasons, with an average water level 3-4 meters below the surface.

[0058] Construction process:

[0059] Geological survey: Using high-precision ground-penetrating radar and deep drilling, the distribution of soil layers and changes in groundwater level were thoroughly investigated, and geological profile maps and parameter charts accurate to the millimeter level were drawn, providing precise data for subsequent construction. For example, geological analysis software accurately determined the internal friction angle of the soft plastic silty clay layer to be 12°, the cohesion to be 18 kPa, and the compression modulus to be 4 MPa. The corresponding parameters for the medium-dense to dense sandy silt layer were 30°, 0 kPa (the cohesion of sandy soil is approximately 0), and 12 MPa, respectively. The groundwater level can reach a maximum of 2.5 meters below the surface during the rainy season and a minimum of 4.5 meters below the surface during the dry season.

[0060] Pile Material Inspection: Prestressed high-strength concrete pipe piles are strictly inspected in accordance with national standards, using advanced ultrasonic testing instruments and total stations. The pile strength deviation is controlled within ±2% of the design strength, the pile diameter deviation is +2mm, the wall thickness deviation is +1mm, the length deviation is +30mm, and the verticality deviation is 0.8 / 1000 of the pile length. The pile joints are tested under a simulated 1.5 times design load to ensure that their sealing, connection firmness, and force transmission performance meet the requirements.

[0061] Equipment commissioning: The hydraulic system and verticality control system of the static pressure pile driver were finely commissioned. The pressure sensor accuracy reached ±0.03MPa, the flow meter accuracy was ±0.08L / min, and there were no leaks or jamming in any hydraulic components. After calibration, the measurement error of the pressure gauge was controlled within ±0.15% of the full scale. The laser calibration device and electronic level ensured that the verticality deviation of the pile driver was always within 0.15%.

[0062] Reasonable planning of pile driving sequence: Based on the site topography, geological conditions and surrounding environment, the construction area is divided into 8 small areas of about 500 square meters each. A combination of zoned pile driving and skip driving is adopted. The central area of ​​the site is constructed first. The interval between adjacent pile construction is determined to be about 30 hours based on geological conditions and pile spacing, which effectively reduces the soil squeezing effect and the risk of pile floating and deviation.

[0063] Controlling pile driving speed: During the pile driving process, based on the geological survey report and the actual site conditions, the pile driving speed is generally controlled at around 0.9 m / min. In soft soil areas, the number of piles completed per day is strictly controlled to 2, and the number of consecutive pile driving days in the same area does not exceed 4 days, ensuring soil stability and pile quality.

[0064] Anti-squeezing trenches and drainage facilities were installed: Anti-squeezing trenches with a depth of 1.8m and a width of 0.8m were installed around the pile driving area. Mechanical excavation combined with manual trimming was used, and the flatness error of the trench walls was controlled within ±3mm, effectively releasing soil stress and protecting surrounding facilities. At the same time, sand wells with a diameter of 0.4m and a wall thickness of 3.5mm were arranged in the pile foundation construction area. The wells were filled with medium-coarse sand with a mud content of no more than 2% as filter material. The wells were arranged at 1.8m intervals in a quincunx pattern and with a depth of 10m. Three rows of wells were set up around the pile driving area to accelerate the dissipation of pore water pressure and reduce the soil squeezing effect.

[0065] Isolation piles and monitoring measures: Jet grouting piles are installed around nearby buildings and underground pipelines as isolation piles. The pile diameter is 0.8m, the pile spacing is 1.6m, and the pile length penetrates the soft soil layer and embeds into the stable stratum for 3.5m. High-precision total station and level are used to monitor the first driven piles in real time, with a monitoring frequency of once every 15 minutes, to promptly grasp the uplift and tilt of the piles. When the verticality deviation of the pile reaches 0.2%, re-driving measures are immediately taken to correct it.

[0066] Pre-drilling reduces resistance: Professional drilling equipment is used to pre-drill holes at the pile location. The hole diameter is 80mm smaller than the pile diameter. For a 30m long pile, the drilling depth is 12m. The verticality deviation of the hole is controlled within three per thousand. Drilling is carried out simultaneously during construction, which effectively reduces the side wall resistance and improves the pile driving efficiency by about 30%.

[0067] Lubricant coating on pile body: A specially developed high-efficiency lubricant is evenly applied to the surface of the pile body with a coating thickness of 2.5mm. Automated spraying equipment is used in combination with manual assistance to ensure that the lubricant is applied evenly, which reduces the pile-soil friction coefficient by about 35% and improves the smoothness and efficiency of pile driving.

[0068] Optimize pile tip design: Based on geological conditions, adopt a tapered pile tip with a cone angle of 50° and a pile tip length of 1.6 times the pile diameter. This facilitates penetration of the upper soft plastic silty clay layer into the lower sandy silt layer, reduces soil resistance to the pile tip, and improves pile driving efficiency and pile stability.

[0069] Underground pile splicing construction: If a broken underground pile is encountered during construction, work is immediately suspended. Manual labor combined with small machinery is used to clean the broken pile area, removing soil, debris, and loose concrete fragments. Then, professional grinding tools are used to grind the joint area smooth to a surface roughness of Ra4.0μm. The joint surface is then cleaned with a high-pressure water gun at 0.6MPa pressure to ensure cleanliness and adhesion. Low-hydrogen welding electrodes conforming to national standards are used for welding. The welding current, voltage, and welding speed are precisely adjusted according to the steel material and thickness of the pile to ensure a full, uniform weld free of porosity and cracks. After the connection is completed, a visual inspection and dimensional verification are performed, with dimensional deviations controlled within ±1.5mm to ensure the pile splicing quality meets requirements.

[0070] Quality Inspection and Acceptance: After the underground pile splicing construction is completed, ultrasonic testing technology is used to conduct non-destructive testing on the pile splicing area. The testing frequency is 1.5MHz. By analyzing the ultrasonic reflected wave signal, no defects were found inside the pile splicing area. At the same time, a low-strain testing method is used to apply an impact force of 20kN to the top of the pile and measure the propagation of stress waves in the pile body to verify the integrity of the pile splicing area. The testing range covers the entire pile splicing area and the pile body above and below it by 2.5m to ensure that the pile splicing area is well connected to the original pile body and has strong integrity. After the construction of 50 pile foundations was completed, a static load test was conducted on the entire pile foundation according to the design requirements. A step-by-step loading method was adopted, with the load amount being 2.5 times the design load. During the loading process, high-precision displacement sensors (accuracy of ±0.03mm) and pressure sensors (accuracy of ±0.08kN) were used to monitor the settlement of the pile top and the load changes in real time. Load-settlement curves were plotted, and based on the curve characteristics and relevant specifications and standards, it was determined that the bearing capacity of the pile foundation met the design requirements. The high-strain test results also showed that the integrity and bearing capacity of the pile foundation were good, ensuring the quality and stability of the entire pile foundation and providing a solid and reliable foundation guarantee for the subsequent construction of the commercial complex.

[0071] Industrial plant foundation construction

[0072] Project Overview: The industrial plant is located in an open area in the suburbs, with no important buildings or complex underground pipelines nearby, but the geological conditions are complex. The upper part is 3-6 meters of miscellaneous fill soil with uneven composition, including bricks, stones and silty clay, etc. The lower part is a deep hard plastic clay with a low groundwater level of 8-10 meters below the surface.

[0073] Construction process:

[0074] Geological exploration: Through high-precision ground-penetrating radar and deep drilling, the distribution of soil layers and their physical and mechanical parameters were thoroughly investigated, and accurate geological profiles and parameter charts were drawn. The internal friction angle of the miscellaneous fill layer is 18° (considering its complex composition, a comprehensive average value is taken), the cohesion is 10 kPa, and the compression modulus is 3 MPa. The internal friction angle of the stiff plastic clay layer is 25°, the cohesion is 30 kPa, and the compression modulus is 8 MPa. The groundwater level is relatively stable, approximately 9 meters below the surface.

[0075] Pile material inspection: Strict quality control is carried out on prestressed high-strength concrete pipe piles. The pile strength deviation is controlled within ±2.5% of the design strength, the pile diameter deviation is +3mm, the wall thickness deviation is +1.5mm, the length deviation is +40mm, the verticality deviation is 0.9 / 1000 of the pile length, and the pile joint is tested under a simulated 1.4 times the design load to ensure that its various performances meet the requirements.

[0076] Construction equipment commissioning: Fine-tuning of each system of the static pressure pile driver was carried out. The accuracy of the pressure sensor reached ±0.04MPa, the accuracy of the flow meter was ±0.09L / min, the hydraulic components had no leakage or jamming, the measurement error of the pressure gauge after calibration was controlled within ±0.18% of the full scale, and the verticality deviation of the pile driver was within 0.16%.

[0077] Reasonable planning of pile driving sequence: The construction area is divided into 6 small areas with an area of ​​about 800 square meters. A combination of zoned pile driving and skip driving is adopted. The edge area of ​​the construction site is constructed first, and the interval between adjacent pile construction is about 24 hours, which effectively reduces the soil squeezing effect and the risk of pile floating and deviation.

[0078] Controlling pile driving speed: During the pile driving process, the pile driving speed is generally controlled at around 1.1 m / min. Depending on the depth of penetration and the surrounding environment, the pile driving speed can be appropriately increased in areas near the edge of the site, but should not exceed 1.3 m / min, to ensure soil stability and pile quality during construction.

[0079] Anti-squeezing trenches and drainage facilities are set up: Anti-squeezing trenches with a depth of 1.7m and a width of 0.8m are set up around the pile driving area. The flatness error of the trench wall is controlled within ±4mm. At the same time, plastic drainage boards are arranged in the pile foundation construction area with a spacing of 1.7m and a quincunx pattern, with a depth of 10m. Two rows are set up around the pile driving area to accelerate the dissipation of pore water pressure and reduce the soil squeezing effect.

[0080] Isolation piles and monitoring measures: Since there are no important facilities in the surrounding area, isolation piles were not set up. However, during the pile driving process, high-precision total stations and levels were used to monitor the first piles driven in. The monitoring frequency was once every 20 minutes to keep track of the pile's uplift and tilt. When the pile top displacement exceeded 30mm, re-pressurization measures were immediately taken to correct it.

[0081] Pre-drilling reduces resistance: Drill holes at the pile location in advance. The diameter of the holes is 70mm smaller than the pile diameter. For a 30m long pile, the drilling depth is 13m. The verticality deviation of the holes is controlled within 0.35%. Drilling is carried out as the pile is driven, which effectively reduces the side wall resistance and improves the pile driving efficiency by about 25%.

[0082] Lubricant coating on pile body: A high-efficiency lubricant is evenly applied to the surface of the pile body with a coating thickness of 2.2mm. Automated spraying equipment is used in combination with manual assistance to ensure that the lubricant is applied evenly, which reduces the pile-soil friction coefficient by about 30% and improves the smoothness and efficiency of pile driving.

[0083] Optimize pile tip design: Based on geological conditions, select flat-bottomed pile tips and set a cutting edge on the edge of the pile tip with a cutting edge angle of 35° and a width of 20mm to enhance the cutting ability and soil penetration performance of the pile tip, reduce the resistance of the soil to the pile tip, and improve the pile driving efficiency and pile stability.

[0084] Underground pile splicing construction: In the event of underground pile breakage during construction, manual labor combined with small machinery is used to clean the broken pile area. The roughness of the connection area is ground to Ra3.5μm. After cleaning the connection surface with a high-pressure water gun at a pressure of 0.5MPa, mechanical connection is performed using connectors and bolts that meet the design load-bearing capacity requirements. The connection is tightened according to the specified torque value, and the torque error is controlled within ±4N·m. After the connection is completed, a visual inspection and dimensional verification are performed, and the deviation of each dimension is controlled within ±1.8mm to ensure that the pile splicing quality meets the requirements.

[0085] Quality Inspection and Acceptance: After the underground pile splicing construction was completed, ultrasonic testing was used to perform non-destructive testing on the splice area at a frequency of 1.3MHz. No internal defects were found in the splice area. Simultaneously, a low-strain testing method was used, applying an impact force of 18kN to the pile top to measure the stress wave propagation in the pile body, verifying the integrity of the splice area. The testing range covered the entire splice area and the pile body above and below it by 2m, ensuring a good connection and strong integrity between the splice area and the original pile body. After completing the construction of 80 pile foundations, high-strain testing was conducted on the entire pile foundation according to design requirements. A transient impact force of 30kN was applied to the pile top, and strain gauges and accelerometers were used to measure the strain and acceleration response of the pile body. The response data was analyzed to evaluate the integrity and bearing capacity of the pile foundation. The results showed that the quality and stability of the pile foundation met the engineering design and usage requirements, providing a solid and reliable foundation guarantee for the construction of the industrial plant.

[0086] The present invention and its embodiments have been described above illustratively. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention. The actual method is not limited to this. Therefore, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A prestressed high-strength concrete pipe pile static pressure driving structure, characterized in that: The system includes a base, an adjustment mechanism fixedly connected to one side of the base, a limit mechanism fixedly connected to the other side of the base, a hydraulic mechanism between the adjustment mechanism and the limit mechanism, a rotating mechanism fixedly connected to the bottom of the hydraulic mechanism, a connecting mechanism fixedly connected to the bottom of the rotating mechanism, and a stake at the bottom of the connecting mechanism; the adjustment mechanism includes a fixed frame, a first motor fixedly connected to the top of the fixed frame, a threaded rod fixedly connected to the output end of the first motor, a threaded sleeve threadedly connected to the surface of the threaded rod; the limit mechanism includes a limit frame, a sliding rod fixedly connected to the inner wall of the limit frame, and a sliding sleeve slidably connected to the surface of the sliding rod. The hydraulic mechanism includes two vertical plates, which are respectively fixedly connected to the surfaces of a threaded sleeve and a sliding sleeve. A horizontal plate is fixedly connected between the vertical plates, and a first hydraulic telescopic rod is passed through the top of the horizontal plate. The rotating mechanism includes a housing, the top of which is fixedly connected to the output end of the first hydraulic telescopic rod. A second motor is fixedly connected to one side of the bottom of the housing, and a first gear is fixedly connected to the output end of the second motor. A vertical rod is movably connected to the bottom of the housing via a bearing, and a second gear is fixedly connected to the top of the vertical rod. The first gear and the second gear mesh. The connecting mechanism includes a connecting plate. The connecting plate is fixed to the bottom of the vertical rod, and a connecting sleeve is fixedly connected to the bottom of the connecting plate. A snap-fit ​​plate is fixedly connected to the inner wall of the connecting sleeve. The top of the pile extends into the inner cavity of the connecting sleeve. An insert plate is fixedly connected to the bottom of the snap-fit ​​plate. A slot for cooperating with the insert plate is opened on the top of the pile. Support plates are fixedly connected to both sides of the connecting sleeve. A second hydraulic telescopic rod is provided through the surface of the support plate. A movable plate is fixedly connected to the output end of the second hydraulic telescopic rod. A fixing block is fixedly connected to the opposite side of the movable plate. Fixing grooves for cooperating with the fixing blocks are opened on the top of both sides of the pile.

2. The prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 1, characterized in that: The base has counterweight grooves fixedly connected to both sides of the top, and counterweight blocks are provided in the inner cavity of the counterweight grooves.

3. The prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 1, characterized in that: Both sides of the base are fixedly connected to a fixing plate, and a pin is provided through the top of the fixing plate. A through hole is opened on the top of the fixing plate to cooperate with the pin.

4. The construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 1, characterized in that: Includes the following steps: Step 1, Geological Survey: Using advanced geological exploration equipment, a combination of high-precision ground-penetrating radar and deep drilling, a comprehensive, detailed and in-depth survey of the construction site is conducted to accurately determine the thickness, type, distribution range of each soil layer, as well as the physical and mechanical parameters of each soil layer, including internal friction angle, cohesion, and compression modulus. The depth of the groundwater level and its changes with seasonal and climatic factors are also recorded in detail. Step 2, Pile Material Inspection: Based on relevant national standards and strict design requirements, comprehensive and high-precision quality control is implemented for prestressed high-strength concrete pipe piles. At the same time, the sealing, connection firmness and force transmission performance of the pile joints are tested. Through tests simulating actual stress conditions, the reliability and stability of the joints under design loads are verified to ensure that they meet the requirements of construction and long-term use. Step 3: Equipment commissioning: Conduct comprehensive, in-depth and meticulous commissioning and inspection of the static pressure pile driver to ensure that all systems of the pile driver operate stably and reliably during construction, providing a solid guarantee for the smooth progress of pile driving operations; Step 4: Rationally plan the pile driving sequence: Taking into account the topography, geological conditions and surrounding environmental factors of the construction site, the entire construction area is scientifically divided into several small areas of moderate size and regular shape. In each small area, the construction is carried out by combining zoned pile driving and skip driving, so that the soil has enough time to adjust stress and consolidate during the process of the pile entering the soil, thereby effectively reducing the risk of soil squeezing effect and pile floating and deviating. Step 5: Control the pile driving speed. During the pile driving process, the pile driving speed shall be strictly controlled according to the geological survey report and the actual site conditions. At the same time, the pile driving speed shall be dynamically adjusted according to the pile penetration depth and the sensitivity of the surrounding environment. In soft soil areas, due to the special mechanical properties of the soil, in order to prevent the problem of excessive soil deformation caused by the untimely dissipation of pore water pressure, the number of piles completed per day shall be strictly controlled not to exceed 3, and the cumulative number of consecutive pile driving days in the same area shall not exceed 5 days, so as to ensure the stability of the soil and the quality of the pile body during the construction process. Step Six: Set up anti-squeezing trenches and drainage facilities: Around the pile driving area, anti-squeezing trenches should be set up reasonably according to the geological conditions of the site and the distribution of surrounding buildings and underground pipelines. The depth of the anti-squeezing trenches should be determined to be 1.6-2.0m and the width should be 0.7-0.9m. Mechanical excavation combined with manual trimming should be used for construction to ensure the flatness and stability of the trench walls, so that they can effectively release soil stress, block the stress transmission path caused by soil squeezing, and protect the surrounding facilities from the impact of soil squeezing. At the same time, sand wells or plastic drainage boards should be set up in the pile foundation construction area at certain intervals and layouts. Step 7: Set up isolation piles and monitoring measures: Around the affected buildings or underground facilities, based on their structural type, foundation form and distance from the pile driving area, reasonably select and set up isolation measures such as pile banks, jet grouting piles, or anti-seepage walls or concrete underground continuous walls. During the pile driving process, use high-precision total stations and levels to monitor the first piles driven in real time and continuously, with a monitoring frequency of no less than once every 20 minutes, to keep track of the pile's uplift and tilt. Step 8: Pre-drilling to reduce resistance: At the pile location, use professional drilling equipment to perform pre-drilling operations. The drilling diameter is determined based on the pile diameter and should be 60-100mm smaller than the pile diameter. The drilling depth is reasonably determined based on the pile length and geological conditions, and should be within the range of 1 / 3-1 / 2 of the pile length. That is, for a 30m long pile, the drilling depth should be controlled between 10-15m. During the drilling process, strictly control the verticality deviation of the drilling to not exceed 0.4% to ensure the concentricity of the drilling and the pile location. Step 9: Apply lubricant to the pile body: Apply a specially developed high-efficiency lubricant evenly to the surface of the pile body, with the thickness controlled between 2-3mm. This ensures that a stable lubricating film can be formed at the pile-soil interface during the pile driving process, effectively reducing the friction coefficient between the pile and the soil. During the application process, an automated spraying equipment combined with manual assistance is used to ensure the uniformity and integrity of the lubricant application, avoiding missed areas or uneven thickness, thereby fully leveraging its role in reducing sidewall resistance and improving the smoothness and efficiency of pile driving. Step 10: Optimize pile tip design: Based on detailed geological survey data of the construction site, and in combination with the characteristics of the pile type and design requirements, conduct targeted optimization design of the pile tip; Step 11, Underground Pile Splicing Construction: When an underground pile breaks during construction, construction should be immediately suspended and the broken pile area should be thoroughly inspected and evaluated. First, using a combination of manual labor and small machinery, carefully clean the soil, debris, and loose concrete fragments around the broken pile area to ensure that the broken pile section is clearly visible and free of residual impurities. Then, use professional grinding tools to finely grind the connection area of ​​the broken pile to make its surface smooth and the roughness meet the design requirements. Use a high-pressure water gun to thoroughly clean the connection surface to remove surface dust and oil, ensuring the cleanliness and adhesion of the connection surface. Next, select appropriate special pile splicing connectors to ensure that the weld is full, uniform, and free of porosity and crack defects. After the connection is completed, conduct a visual inspection and dimensional verification of the connection area to ensure that the quality of the pile splicing meets the relevant standards and design requirements. Step Twelve, Quality Inspection and Acceptance: After the underground pile splicing construction is completed, non-destructive testing should be carried out on the splicing area in a timely manner. When using ultrasonic testing technology, the testing probes should be arranged according to relevant standards and specifications to comprehensively scan the weld or connection area. The testing frequency should not be lower than 1.2MHz. By analyzing the reflected wave signals of the ultrasonic waves, it is determined whether there are any defects inside the splicing area to ensure the internal quality of the splice. At the same time, a low-strain testing method is used to measure the stress wave propagation of the pile body by applying impact force to the pile top to further verify the integrity of the splicing area. The pile length range of the test should cover the entire splicing area and a certain length of the pile body above and below to ensure that the splicing area is well connected to the original pile body and has strong integrity. In addition, after completing a certain number of pile foundation constructions, according to In accordance with design requirements and relevant specifications, static load tests or high-strain tests are conducted on the entire pile foundation. Static load tests employ a step-by-step loading method, with the load amount determined as a multiple of the design load. During loading, high-precision displacement and pressure sensors are used to monitor the settlement and load changes at the pile top in real time, generating load-settlement curves. Based on the curve characteristics and relevant standards, the bearing capacity of the pile foundation is determined to meet design requirements. High-strain tests involve applying transient impact force to the pile top and using strain gauges and accelerometers to measure the strain and acceleration response of the pile body. By analyzing these response data, the integrity and bearing capacity of the pile foundation are evaluated, ensuring that the quality and stability of the entire pile foundation meet engineering design and usage requirements, providing a solid and reliable foundation for subsequent construction.

5. The construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 4, characterized in that: In step one, the data are systematically analyzed and organized using professional geological analysis software to draw geological profile maps and related parameter charts accurate to the millimeter level, providing detailed and reliable geological basis for the formulation of subsequent construction plans.

6. The construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 4, characterized in that: In step two, advanced ultrasonic testing equipment and total station equipment are used to perform non-destructive testing on the strength of the pile body to ensure that it reaches the design strength level and the strength distribution is uniform, with the strength deviation controlled within ±3% of the design strength; the dimensions of the pile body are accurately measured, including diameter, wall thickness and length; and professional verticality testing tools are used to ensure that the verticality of the pile body meets the specifications and the deviation does not exceed one-thousandth of the pile length.

7. The construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 4, characterized in that: In step three, for the hydraulic system, high-precision pressure sensors and flow meters are used to check whether the pressure and flow of the hydraulic oil are stable and meet the working requirements of the pile driver. The sealing and operational flexibility of each hydraulic component, such as the oil pump, oil cylinder, and control valve, are tested to ensure that there are no leaks or jamming. The pressure gauge is calibrated with high precision to control its measurement error within a very small range so as to accurately reflect the pressure changes during the pile driving process. The verticality control system is precisely adjusted using a laser calibration device and an electronic level to ensure that the pile driver can automatically adjust the verticality of the pile in real time during the pile driving process, keeping it within the allowable deviation range.

8. The construction method of a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 4, characterized in that: In step six, the sand wells use circular steel pipes with a diameter of 0.4m as the well walls, filled with well-graded medium-coarse sand as filter material, arranged at intervals of 1.6-2.0m in a quincunx pattern, with a depth of about 10m. Two or three rows are set around the pile driving area to further reduce the adverse effects of soil squeezing on the soil and pile body by accelerating the dissipation of pore water pressure.

9. The construction method for a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 4, characterized in that: In step eight, the construction process adopts the method of drilling and driving simultaneously, that is, the pile driving operation is carried out immediately after the drilling is completed, so that the pile body can sink in a relatively loose soil environment, effectively reducing the friction between the pile sidewall and the soil, significantly improving the pile driving efficiency, and reducing the construction difficulty and energy consumption.

10. The construction method of a prestressed high-strength concrete pipe pile static pressure pile driving structure according to claim 4, characterized in that: In step ten, for geological conditions where the upper layer is a relatively soft soil layer and the lower layer is a relatively hard soil layer, a conical pile tip is used. The cone angle is determined between 40° and 60° based on the mechanical properties of the soil layer and the pile diameter. The length of the pile tip is 1.2 to 2.0 times the pile diameter. Through the soil squeezing and breaking action of the conical pile tip, the pile body can more easily penetrate the upper soft soil layer and enter the lower hard soil layer. For cases where the strata are relatively uniform and hard, a flat-bottomed pile tip is selected, and an appropriate cutting edge is set on the edge of the pile tip. The cutting edge angle is 25° to 45° and the width is 15 to 30 mm to enhance the cutting ability and soil penetration performance of the pile tip, reduce the resistance of the soil to the pile tip, and improve the pile driving efficiency and the stability of the pile body.

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