Static pressure pile sinking structure of prestressed high-strength concrete pipe pile and construction method

Abstract

The invention discloses a static pressure pile sinking structure of a prestressed high-strength concrete pipe pile and a construction method, and belongs to the technical field of pipe pile construction. An adjusting mechanism is fixedly connected to one side of the base, a limiting mechanism is fixedly connected to the other side of the base, a hydraulic mechanism is arranged between the adjusting mechanism and the limiting mechanism, a rotating mechanism is fixedly connected to the bottom of the hydraulic mechanism, a connecting mechanism is fixedly connected to the bottom of the rotating mechanism, and a pile body is arranged at the bottom of the connecting mechanism. 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, the surface of the threaded rod is in threaded connection 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 slidably connected with a sliding sleeve. Through cooperation of the intelligent monitoring and regulation system and the innovative pile-soil action optimization technology, the problems that the soil squeezing effect is difficult to effectively control and the risk of upward floating and deviation of the pile body is high at present are solved.

Description

Technical Field

[0001] The invention relates to the technical field of pipe pile construction, in particular to a prestressed high-strength concrete pipe pile static pressure sinking pile structure and a construction method. Background Art

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

[0003] However, in actual engineering applications, especially in the face of increasingly complex building environments and diverse geological conditions, the limitations of traditional methods are gradually exposed. On the one hand, in complex soil foundation areas, such as soft soil layers, saturated clay soil, sites with thick sand layers or uneven soil, the soil squeezing effect during the pipe pile sinking 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 is significantly displaced, and the pore water pressure changes suddenly, often causing serious consequences such as ground uplift, 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 floating and deflection phenomenon of the pile body occurs frequently, which is particularly prominent in soft soil foundations. During the construction process, the ultra-long prestressed pipe piles are prone to deflection, floating or even breaking due to the lateral displacement of the soil around the pile and their own stability problems, which greatly affects the bearing capacity of the pile foundation and the stability of the overall structure, and increases the quality risks of the project and the subsequent repair costs.

[0004] In addition to the above-mentioned quality and safety issues, traditional construction methods are also in trouble in terms of construction efficiency and cost control. The side wall resistance during the pile sinking process is large, which causes the pile driver to consume more energy to overcome the resistance, slowing the pile sinking speed and extending the construction period. This not only increases the rental costs and fuel consumption of mechanical equipment, but may also bring additional indirect costs due to construction delays. In addition, when encountering underground broken piles, traditional treatment methods are often complicated, time-consuming and labor-intensive, and the quality of pile connections is difficult to guarantee. It often requires a lot of manpower, material and financial resources for repair or re-construction, further exacerbating the rise in construction costs and greatly reducing the economic benefits of the project. An innovative structure and construction method is urgently needed to break this deadlock and achieve efficient, high-quality and economical balanced development of building foundation construction. Summary of the invention

[0005] The purpose of the present invention is to provide a prestressed high-strength concrete pipe pile static pressure sinking pile structure and construction method, which solves the problems in the prior art that the soil squeezing effect is difficult to effectively control and the risk of pile body floating deviation is high through the cooperation of an intelligent monitoring and control system and an innovative pile-soil interaction optimization technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

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

[0008] The hydraulic mechanism includes a vertical plate, and the two vertical plates are respectively fixedly connected to the threaded sleeve and the sliding sleeve surface, a horizontal plate is fixedly connected between the vertical plates, and a first hydraulic telescopic rod is penetrated on the top of the horizontal plate, and the rotating mechanism includes a box body, the top of the box body 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 box body cavity, and the output end of the second motor is fixedly connected to the first gear, the bottom of the box body is movably connected to the vertical rod through a bearing, and the top of the vertical rod is fixedly connected to the second gear, and the first gear is meshed with the second gear, and the connecting mechanism includes a connecting plate The connecting plate is fixed to the bottom of the vertical rod, the bottom of the connecting plate is fixedly connected with a connecting sleeve, the inner wall of the connecting sleeve is fixedly connected with a clamping plate, the top of the pile body extends to the inner cavity of the connecting sleeve, the bottom of the clamping plate is fixedly connected with a plug plate, the top of the pile body is provided with a slot for use with the plug plate, both sides of the connecting sleeve are fixedly connected with support plates, the surface of the support plate is penetrated by a second hydraulic telescopic rod, the output end of the second hydraulic telescopic rod is fixedly connected with a moving plate, the opposite side of the moving plate is fixedly connected with a fixed block, and the top of both sides of the pile body is provided with fixing grooves for use with the fixed block.

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

[0010] Furthermore, both sides of the base are fixedly connected with fixing plates, a pin rod is penetrated through the top of the fixing plate, and a through hole used for matching with the pin rod is opened on the top of the fixing plate.

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

[0012] Step 1: Geological survey: Use advanced geological exploration equipment, high-precision geological radar and deep drilling to conduct a comprehensive, detailed and in-depth survey of the construction site, accurately determine the thickness, type, distribution range and physical and mechanical parameters of each soil layer, including but not limited to internal friction angle, cohesion, compression modulus, and record in detail the depth of the groundwater level and its changes with seasons and climate factors;

[0013] Step 2: Pile material inspection: Based on relevant national standards and strict design requirements, we implement all-round and high-precision quality control on prestressed high-strength concrete pipe piles. At the same time, we test the sealing, connection firmness and force transmission performance of the pile joints. Through tests simulating actual stress conditions, we verify the reliability and stability of the joints when bearing the design load to ensure that they meet the requirements of construction and long-term use.

[0014] Step 3: Construction equipment debugging: Carry out comprehensive, in-depth and meticulous debugging and inspection of the static pressure pile driver to ensure that all systems of the pile driver operate stably and have reliable performance during the construction process, providing a solid guarantee for the smooth progress of the pile sinking operation;

[0015] Step 4: Reasonably plan the sequence of pile driving: comprehensively consider the topography, geological conditions and surrounding environmental factors of the construction site, scientifically divide the entire construction area into several small areas with moderate areas and regular shapes, and use a combination of zoned pile driving and skip driving in each small area to ensure that the soil has enough time to adjust stress and consolidate during the process of the pile body 7 being buried, thereby effectively reducing the risk of soil squeezing effect and floating deviation of the pile body;

[0016] Step 5: Control the pile sinking speed: During the pile sinking process, the pile sinking speed is strictly controlled according to the geological survey report and the actual situation on site. At the same time, the pile sinking speed is dynamically adjusted according to the depth of the pile into the soil 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 excessive deformation of the soil caused by the untimely dissipation of pore water pressure, the number of piles per day is strictly controlled not to exceed 3, and the number of consecutive days of pile sinking in the same area shall not exceed 5 days in total, to ensure the stability of the soil and the quality of the pile body during the construction process;

[0017] Step 6. Set up anti-crowding ditches and drainage facilities: around the pile sinking area, reasonably set up anti-crowding ditches according to the geological conditions of the site and the distribution of surrounding buildings and underground pipelines. The depth of the anti-crowding ditch 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 finishing to ensure the flatness and stability of the ditch wall, so that it can effectively release soil stress, block the stress transmission path caused by soil squeezing, and protect surrounding facilities from the impact of soil squeezing. At the same time, in the pile foundation construction area, set up sand wells or plastic drainage boards at a certain spacing and layout;

[0018] Step 7. Set up isolation piles and monitoring measures: around the buildings or underground facilities that are affected, reasonably select and set up isolation measures such as pile rows, jet grouting piles or anti-seepage walls, and concrete underground continuous walls according to their structural type, foundation form, and distance from the pile-sinking area. During the piling process, use high-precision total stations and levels to conduct real-time and continuous monitoring of the piles driven first, with a monitoring frequency of no less than once every 20 minutes, so as to timely grasp the floating and tilting conditions of the piles;

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

[0020] Step 9: Apply lubricant to the pile body: Apply specially developed high-efficiency lubricant evenly on the surface of the pile body, and control the coating thickness between 2-3mm to ensure that a stable lubricating film can be formed at the pile-soil interface during the process of the pile body entering the soil, effectively reducing the friction coefficient between the pile and the soil. During the coating process, use automated spraying equipment combined with manual assistance to ensure the uniformity and integrity of the lubricant coating, avoid missing coating or uneven thickness, so as to give full play to its role in reducing side wall resistance and improve the smoothness and efficiency of pile sinking;

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

[0022] Step 11, underground pile connection construction: When underground piles are broken during the construction process, the construction should be suspended immediately and the broken pile parts should be inspected and evaluated in detail. First, the soil, debris and loose concrete fragments around the broken pile parts should be carefully cleaned by manual and small machinery to ensure that the cross section of the broken pile is clearly visible and free of residual impurities. Then, professional grinding tools should be used to finely grind the connection parts of the broken piles to make their surface flat and rough to meet the design requirements. High-pressure water guns should be used to thoroughly clean the connection surfaces to remove dust and oil on the surface to ensure the cleanliness and bonding performance of the connection surfaces. Then, suitable special pile connection connectors should be selected to ensure that the welds are full, uniform, and free of pores and cracks. After the connection is completed, the connection parts should be visually inspected and the dimensions reviewed to ensure that the quality of the pile connection meets the relevant standards and design requirements.

[0023] Step 12, quality inspection and acceptance: After the underground pile connection construction is completed, the connection pile part shall be promptly subjected to non-destructive testing. When ultrasonic testing technology is used, the detection probe shall be arranged in accordance with relevant standards and specifications, and the weld or connection part shall be fully scanned. The detection frequency shall not be less than 1.2MHz. By analyzing the reflected wave signal of the ultrasonic wave, it is determined whether there are defects inside the connection pile part to ensure the internal quality of the connection pile. At the same time, the low-strain detection 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 connection pile part. The detected pile length range shall cover the entire connection pile part and a certain length of the pile body above and below to ensure that the connection pile part is well connected with the original pile body and has strong integrity. In addition, after completing a certain number of pile foundation construction, according to According to the design requirements and relevant specifications, the entire pile foundation is subjected to static load test or high strain detection. The static load test adopts a step-by-step loading method, and the loading amount is determined according to the multiple of the design load. During the loading process, high-precision displacement sensors and pressure sensors are used to monitor the settlement and load changes of the pile top in real time, and the load-settlement curve is drawn. According to the curve characteristics and relevant specifications and standards, it is judged whether the bearing capacity of the pile foundation meets the design requirements. The high strain test applies a transient impact force to the pile top, and uses 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 to ensure that the quality and stability of the entire pile foundation meet the engineering design and use requirements, providing a solid and reliable foundation guarantee for subsequent engineering construction.

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

[0025] Furthermore, in step 2, advanced ultrasonic detectors and total station equipment are used to perform non-destructive testing on the strength of the pile body to ensure that it reaches the designed strength level and the strength distribution is uniform, and the strength deviation is controlled within ±3% of the designed strength; the dimensions of the pile body are accurately measured, including diameter, wall thickness, and length; and professional verticality detection tools are used to ensure that the verticality of the pile body meets the specification requirements and the deviation does not exceed one thousandth of the pile length.

[0026] Furthermore, in step three, for the hydraulic system, high-precision pressure sensors and flow testers are used to check whether the pressure and flow of the hydraulic oil are stable and meet the working requirements of the pile driver, and the sealing and movement flexibility of various hydraulic components such as oil pumps, oil cylinders, control valves, etc. are tested to ensure that there is no leakage and jamming; the pressure gauge is calibrated with high precision to control its measurement error within a very small range to accurately reflect the pressure changes during the process of the pile body being buried in the soil; the verticality control system is accurately debugged through a laser calibration device and an electronic level to ensure that the pile driver can automatically adjust the verticality of the pile body in real time during the pile sinking process to keep it within the allowable deviation range at all times.

[0027] Furthermore, in the step six, the sand well uses a circular steel pipe with a diameter of 0.4m as the well wall, and is filled with well-graded medium-coarse sand as filter material. The arrangement spacing is 1.6-2.0m, arranged in a plum blossom shape, and the depth reaches about 10m. Two or three rows are arranged around the pile sinking area, respectively, to further reduce the adverse effects of the soil squeezing effect on the soil and the pile body by accelerating the dissipation of the pore water pressure.

[0028] Furthermore, during the construction in step eight, the drilling-as-you-go method 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 side wall of the pile body and the soil, significantly improving the pile driving efficiency, and reducing the construction difficulty and energy consumption.

[0029] Furthermore, in the step 10, for the 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 to be between 40° and 60° according to the mechanical properties of the soil layer and the pile diameter, and the length of the pile tip is 1.2-2.0 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 and enter the lower hard soil layer; for the situation 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, with a cutting edge angle of 25°-45° and a width of 15-30mm, so as 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 sinking efficiency and the stability of the pile body.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] In terms of construction quality and efficiency, the present invention has reliable pile body quality, factory-based standardized production to ensure its stability, accurate reading of pile pressure force during pile sinking, less human interference, and fast static pressure construction speed, flexible pile matching, and convenient extension, which can effectively shorten the construction period; in terms of environment and safety, there is no vibration, low noise, and good environmental protection performance, so it is suitable for areas with high environmental requirements. At the same time, the construction stress is small, easy to control, with a high degree of mechanization and simple operation, which reduces the risk of pile body quality problems and the probability of safety accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a structural stereogram of the present invention;

[0033] Figure 2 It is a three-dimensional diagram of the base and related structures of the present invention;

[0034] Figure 3 It is a three-dimensional diagram of the limiting mechanism of the present invention;

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

[0036] Figure 5 It is a three-dimensional diagram of the hydraulic mechanism of the present invention;

[0037] Figure 6 It is a three-dimensional diagram of the adjustment mechanism of the present invention;

[0038] Figure 7 It is a construction flow chart of the present invention.

[0039] In the figure: 1, base; 2, adjustment mechanism; 3, limit mechanism; 4, hydraulic mechanism; 5, rotation mechanism; 6, connection mechanism; 7, pile body; 201, fixed frame; 202, first motor; 203, threaded rod; 204, threaded sleeve; 301, limit frame; 302, slide rod; 303, slide 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, clamping plate; 604, plug plate; 605, support plate; 606, second hydraulic telescopic rod; 607, moving plate; 608, fixed block. DETAILED DESCRIPTION

[0040] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] See also Figure 1-7 The present embodiment provides the following technical solutions: a prestressed high-strength concrete pipe pile static pressure sinking pile structure, comprising a base 1, one side of the base 1 is fixedly connected to an adjusting mechanism 2, the other side of the base 1 is fixedly connected to a limiting mechanism 3, a hydraulic mechanism 4 is arranged between the adjusting mechanism 2 and the limiting mechanism 3, the bottom of the hydraulic mechanism 4 is fixedly connected to a rotating mechanism 5, the bottom of the rotating mechanism 5 is fixedly connected to a connecting mechanism 6, and the bottom of the connecting mechanism 6 is arranged with a pile body 7; the adjusting mechanism 2 comprises a fixing frame 201, the top of the fixing frame 201 is fixedly connected to a first motor 202, the output end of the first motor 202 is fixedly connected to a threaded rod 203, and the threaded rod 20 3 is threadedly connected with a threaded sleeve 204, the limiting mechanism 3 includes a limiting frame 301, the inner wall of the limiting frame 301 is fixedly connected with a sliding rod 302, and the surface of the sliding rod 302 is slidably connected with a sliding sleeve 303; the hydraulic mechanism 4 includes a vertical plate 401, the two vertical plates 401 are respectively fixedly connected to the threaded sleeve 204 and the surface of the sliding sleeve 303, a horizontal plate 402 is fixedly connected between the vertical plates 401, and a first hydraulic telescopic rod 403 is penetrated at the top of the horizontal plate 402, and the rotating mechanism 5 includes a box body 501, the top of the box body 501 is fixedly connected to the output end of the first hydraulic telescopic rod 403, and one side of the bottom of the inner cavity of the box body 501 is fixedly connected to the second The first gear 503 is fixedly connected to the output end of the second motor 502, the bottom of the box body 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 is meshed with the second gear 505, 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 clamping plate 603, the top of the pile body 7 extends to the inner cavity of the connecting sleeve 602, the bottom of the clamping plate 603 is fixedly connected to the plug plate 604, and the top of the pile body 7 is provided with a The plug plate 604 is used in conjunction with a slot, and support plates 605 are fixedly connected on both sides of the connecting sleeve 602. A second hydraulic telescopic rod 606 is arranged on the surface of the support plate 605, and a movable plate 607 is fixedly connected to the output end of the second hydraulic telescopic rod 606. A fixed block 608 is fixedly connected to the opposite side of the movable plate 607. Fixed grooves used in conjunction with the fixed block 608 are provided on the top of both sides of the pile body 7, matching grooves are fixedly connected on both sides of the top of the base 1, a counterweight block is provided in the inner cavity of the counterweight groove, and fixed plates are fixedly connected on both sides of the base 1. A pin rod is arranged on the top of the fixed plate, and a through hole used in conjunction with the pin rod is provided on the top of the fixed plate.

[0042] The first motor 202 is started, and the first motor 202 drives the threaded rod 203 to rotate. The threaded rod 203 drives the threaded sleeve 204 to move downward. A moving groove is provided in the inner cavity of the fixed frame 201. A moving block is slidably connected to the inner wall of the moving groove. The moving groove cooperates with the moving block to limit the threaded sleeve 204, thereby improving the stability of the threaded sleeve 204 when it moves up and down. The threaded sleeve 204 drives the hydraulic mechanism 4 to move up and down to adjust the use 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 cooperates with the sliding rod 302 to improve the stability of the night pressing mechanism when it moves up and down The user inserts the top of the pile body 7 into the inner cavity of the connecting sleeve 602, starts the second hydraulic telescopic rod 606, and the second hydraulic telescopic rod 606 drives the movable plate 607 to move, and the movable plate 607 drives the fixed block 608 to insert into the fixed groove, and the fixed block 608 cooperates with the fixed groove and the movable plate 607 to fix the pile body 7, and starts the first hydraulic telescopic rod 403. The first hydraulic telescopic rod 403 drives the pile body 7 to be pressed down through the rotating mechanism 5 and the connecting mechanism 6. During the pressing process, the second motor 502 can be started, and the second motor 502 drives the pile body 7 to rotate through the connecting mechanism 6 to achieve the purpose of rotating and pressing down.

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

[0044] Step a: Geological survey: Use advanced geological exploration equipment, high-precision geological radar and deep drilling to conduct a comprehensive, detailed and in-depth survey of the construction site, accurately measure the thickness, type, distribution range and physical and mechanical parameters of each soil layer, including but not limited to internal friction angle, cohesion, compression modulus, and record the depth of the groundwater level and its changes with seasons and climate factors in detail. Use professional geological analysis software to systematically analyze and organize these data, draw geological profiles and related parameter charts accurate to the millimeter level, and provide detailed and reliable geological basis for the formulation of subsequent construction plans;

[0045] Step b: Pile material inspection: According to relevant national standards and strict design requirements, all-round and high-precision quality control is implemented for prestressed high-strength concrete pipe piles. At the same time, 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 when bearing the design load are verified to ensure that they meet the requirements of construction and long-term use. Advanced ultrasonic detectors and total station equipment are used to conduct non-destructive testing of the strength of the pile body to ensure that it reaches the design strength grade and the strength distribution is uniform, and the strength deviation is controlled within ±3% of the design strength; the dimensions of the pile body are accurately measured, including diameter, wall thickness, and length; professional verticality detection tools are used to ensure that the verticality of the pile body meets the specification requirements, and the deviation does not exceed one thousandth of the pile length;

[0046] Step c: Construction equipment debugging: Conduct comprehensive, in-depth and meticulous debugging and inspection of the static pressure pile driver to ensure that all systems of the pile driver are running stably and with reliable performance during the construction process, and provide solid guarantee for the smooth progress of the pile driving operation. For the hydraulic system, use high-precision pressure sensors and flow testers to check whether the pressure and flow of the hydraulic oil are stable and meet the working requirements of the pile driver. Perform sealing and movement flexibility tests on various hydraulic components such as oil pumps, oil cylinders, and control valves to ensure that there is no leakage or jamming. Perform high-precision calibration on the pressure gauge to control its measurement error within a very small range to accurately reflect the pressure changes during the process of the pile body entering the soil. Use laser calibration devices and electronic levels to accurately debug the verticality control system to ensure that the pile driver can automatically adjust the verticality of the pile body in real time during the pile driving process to keep it within the allowable deviation range at all times.

[0047] Step d: Reasonably plan the sequence of pile driving: comprehensively consider the topography, geological conditions and surrounding environmental factors of the construction site, scientifically divide the entire construction area into several small areas with moderate areas and regular shapes, and use a combination of zoned pile driving and skip driving in each small area to carry out construction, so that the soil has enough time to adjust the stress and consolidate during the process of the pile body 7 being buried, thereby effectively reducing the risk of soil squeezing effect and floating deviation of the pile body;

[0048] Step e: Control the pile sinking speed: During the pile sinking process, the pile sinking speed is strictly controlled according to the geological survey report and the actual situation on site. At the same time, the pile sinking speed is dynamically adjusted according to the depth of the pile into the soil 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 excessive deformation of the soil caused by the untimely dissipation of pore water pressure, the number of piles per day is strictly controlled not to exceed 3, and the cumulative number of days for continuous pile sinking in the same area shall not exceed 5 days, to ensure the stability of the soil and the quality of the pile body during the construction process;

[0049] Step f: Set up anti-squeezing ditches and drainage facilities: around the pile sinking area, according to the geological conditions of the site and the distribution of surrounding buildings and underground pipelines, reasonably set up anti-squeezing ditches, the depth of the anti-squeezing ditch is determined to be 1.6-2.0m, the width is 0.7-0.9m, and the construction is carried out by mechanical excavation combined with manual finishing to ensure the flatness and stability of the ditch wall, so that it can effectively release the soil stress, block the stress transfer path caused 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 according to a certain spacing and layout. The sand well uses a circular steel pipe with a diameter of 0.4m as the well wall, and has well-graded medium and coarse sand as the filter material. The arrangement spacing is 1.6-2.0m, arranged in a plum blossom shape, and the depth reaches about 10m. Two or three rows are set around the pile sinking area to further reduce the adverse effects of the squeezing effect 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 buildings or underground facilities that are affected, rationally select and set up isolation measures such as pile rows, jet grouting piles or anti-seepage walls, and concrete underground continuous walls, based on their structural type, foundation form, and distance from the pile-sinking area. During the piling process, use a high-precision total station and level to conduct real-time and continuous monitoring of the piles driven first, with a monitoring frequency of no less than once every 20 minutes, so as to timely grasp the floating and tilting conditions of the piles;

[0051] Step h: Pre-drilling to reduce resistance: At the pile position, pre-drilling operations are performed using professional drilling equipment. The diameter of the drill hole is determined to be 60-100 mm smaller than the pile diameter based on the pile diameter. The drilling depth is reasonably determined to be 1 / 3-1 / 2 of the pile length based on the pile length and geological conditions, that is, for a 30m long pile, the drilling depth is controlled between 10-15m. During the drilling process, the verticality deviation of the drill hole is strictly controlled to not exceed 0.4 thousandths to ensure the concentricity of the drill hole and the pile position. During construction, the drilling-as-you-drill method is adopted, that is, the pile sinking 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 side wall of the pile body and the soil, significantly improving the pile sinking efficiency, and reducing the construction difficulty and energy consumption;

[0052] Step i: Apply lubricant to the pile body: Apply specially developed high-efficiency lubricant evenly on the surface of the pile body, and control the coating thickness between 2-3mm to ensure that a stable lubricating film can be formed at the pile-soil interface during the process of the pile body entering the soil, effectively reducing the friction coefficient between the pile and the soil. During the coating process, use automated spraying equipment combined with manual assistance to ensure the uniformity and integrity of the lubricant coating, avoid missing coating or uneven thickness, so as to give full play to its role in reducing side wall resistance and improve the smoothness and efficiency of pile sinking;

[0053] Step j: Optimize the pile tip design: According to the detailed geological survey data of the construction site, combined with the characteristics of the pile type and design requirements, the pile tip is optimized and designed in a targeted manner. 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 to be between 40° and 60° according to the mechanical properties of the soil layer and the pile diameter. The length of the pile tip is 1.2-2.0 times the pile diameter. Through the soil squeezing and breaking effect of the conical pile tip, the pile body can more easily penetrate the upper soft soil and enter the lower hard soil layer; for relatively uniform and hard strata, a flat-bottomed pile tip is selected, and an appropriate blade is set on the edge of the pile tip. The blade 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 sinking efficiency and the stability of the pile body;

[0054] Step k: Underground pile connection construction: When underground piles are broken during the construction process, the construction should be suspended immediately and the broken pile parts should be inspected and evaluated in detail. First, the soil, debris and loose concrete fragments around the broken pile parts should be carefully cleaned by manual and small machinery to ensure that the cross-section of the broken pile is clearly visible and free of residual impurities. Then, professional grinding tools should be used to finely grind the connection parts of the broken piles to make their surface flat and rough to meet the design requirements. High-pressure water guns should be used to thoroughly clean the connection surfaces to remove dust and oil on the surface to ensure the cleanliness and bonding performance of the connection surfaces. Then, suitable special pile connection connectors should be selected to ensure that the welds are full, uniform, and free of pores and cracks. After the connection is completed, the connection parts should be inspected for appearance and size to ensure that the quality of the pile connection meets the relevant standards and design requirements.

[0055] Step 1: Quality inspection and acceptance: After the underground pile connection construction is completed, the connection pile part shall be promptly subjected to non-destructive testing. When ultrasonic testing technology is used, the detection probe shall be arranged in accordance with relevant standards and specifications, and the weld or connection part shall be fully scanned. The detection frequency shall not be less than 1.2MHz. By analyzing the reflected wave signal of the ultrasonic wave, it is determined whether there are defects inside the connection pile part to ensure the internal quality of the connection pile. At the same time, the low-strain detection 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 connection pile part. The detected pile length range shall cover the entire connection pile part and a certain length of the pile body above and below to ensure that the connection pile part is well connected with the original pile body and has strong integrity. In addition, after a certain number of pile foundation constructions are completed, the connection pile shall be inspected according to the design. According to the design requirements and relevant specifications, the entire pile foundation is subjected to static load test or high strain test. The static load test adopts a step-by-step loading method, and the loading amount is determined according to the multiple of the design load. During the loading process, high-precision displacement sensors and pressure sensors are used to monitor the settlement and load changes of the pile top in real time, and the load-settlement curve is drawn. According to the curve characteristics and relevant specifications and standards, it is judged whether the bearing capacity of the pile foundation meets the design requirements. The high strain test applies a transient impact force to the pile top, and uses 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 to ensure that the quality and stability of the entire pile foundation meet the engineering design and use requirements, providing a solid and reliable foundation guarantee for subsequent engineering construction.

[0056] Urban commercial complex foundation construction

[0057] Project Overview: The commercial complex is located in a prosperous area of ​​the city, surrounded by dense buildings and complex underground pipelines. The geological conditions are soft plastic silty clay 5-8 meters above and medium-dense to dense sandy silt below. The groundwater level is high and varies significantly with the seasons. The average water level is 3-4 meters below the surface.

[0058] Construction process:

[0059] Geological survey: Using high-precision geological radar and deep drilling, the soil layer distribution and groundwater level changes were identified in detail, and geological profiles and parameter charts accurate to the millimeter level were drawn, providing an accurate basis for subsequent construction. For example, the internal friction angle of the soft plastic silty clay layer was accurately determined to be 12°, the cohesion was 18kPa, and the compression modulus was 4MPa through geological analysis software. The corresponding parameters of the medium-dense-dense sandy silt layer were 30°, 0kPa (the cohesion of sandy soil is approximately 0) and 12MPa, respectively. The groundwater level can reach up to 2.5 meters below the surface in the rainy season and as low as 4.5 meters below the surface in the dry season.

[0060] Pile material inspection: Prestressed high-strength concrete pipe piles are inspected strictly in accordance with national standards, using advanced ultrasonic detectors and total stations. The pile body 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 thousandths of the pile length. The pile joints are tested by simulating 1.5 times the design load to ensure that their sealing, connection firmness and force transmission performance meet the requirements.

[0061] Construction equipment debugging: The hydraulic system and verticality control system of the static pressure pile driver are finely debugged. The pressure sensor accuracy reaches ±0.03MPa, the flow tester accuracy is ±0.08L / min, and the hydraulic components are leak-free and jammed. After the pressure gauge is calibrated, the measurement error is controlled within ±0.15% of the full scale. The laser calibration device and electronic level ensure that the verticality deviation of the pile driver is always within 1.5 thousandths.

[0062] Reasonable planning of pile driving sequence: According to the site topography, geological conditions and surrounding environment, the construction area is divided into 8 areas with an area of ​​about 500 square meters. The method of combining zoned pile driving and skipping is adopted. The central area of ​​the site is constructed first. The interval time between adjacent pile construction is determined to be about 30 hours based on the geological conditions and the distance between piles, which effectively reduces the soil squeezing effect and the risk of floating deviation of the pile body.

[0063] Control the pile driving speed: During the pile driving process, according to the geological survey report and the actual situation on site, the pile driving speed is generally controlled at about 0.9m / min. In the soft soil area, the number of piles per day is strictly controlled to 2, and the number of consecutive pile driving days in the same area shall not exceed 4 days, ensuring the stability of the soil and the quality of the pile body.

[0064] Set up anti-crowding ditches and drainage facilities: set up anti-crowding ditches with a depth of 1.8m and a width of 0.8m around the pile sinking area, using mechanical excavation combined with manual finishing, and the flatness error of the ditch wall is controlled within ±3mm, effectively releasing soil stress and protecting surrounding facilities. At the same time, sand wells are arranged in the pile foundation construction area, with a diameter of 0.4m and a wall thickness of 3.5mm. Medium-coarse sand with a mud content of no more than 2% is built in as filter material. The spacing is 1.8m, arranged in a plum blossom shape, with a depth of 10m, and 3 rows are set around the pile sinking area to accelerate the dissipation of pore water pressure and reduce the soil squeezing effect.

[0065] Setting up isolation piles and monitoring measures: Jet-jet piles are set up as isolation piles around nearby buildings and underground pipelines. The pile diameter is 0.8m, the pile spacing is 1.6m, and the pile length penetrates the soft soil layer and is embedded in the stable stratum for 3.5m. High-precision total stations and levels are used to conduct real-time monitoring of the piles driven first. The monitoring frequency is once every 15 minutes to timely grasp the floating and tilting of the piles. When the verticality deviation of the pile body 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 diameter of the hole is 80mm smaller than the pile diameter. For a 30m long pile, the drilling depth is 12m, and the verticality deviation of the hole is controlled within 0.3%. During construction, drilling is carried out as the pile is being drilled, which effectively reduces the side wall resistance and improves the pile sinking efficiency by about 30%.

[0067] Lubricant coating on the pile body: Evenly apply a specially developed high-efficiency lubricant on the surface of the pile body with a coating thickness of 2.5mm. Use automated spraying equipment combined with manual assistance to ensure that the lubricant is evenly applied, reducing the pile-soil friction coefficient by about 35%, thereby improving the smoothness and efficiency of pile sinking.

[0068] Optimize pile tip design: According to geological conditions, a conical pile tip is adopted with a cone angle of 50° and a pile tip length of 1.6 times the pile diameter, which is convenient for penetrating the upper soft plastic silty clay layer into the lower sandy silt layer, reducing the resistance of the soil to the pile tip, and improving the pile sinking efficiency and pile stability.

[0069] Underground pile connection construction: If an underground pile breaks during the construction process, the construction will be suspended immediately, and the broken pile part will be cleaned manually with small machinery. After removing the dirt, debris and loose concrete fragments, the connection part will be polished flat with professional grinding tools to a roughness of Ra4.0μm, and the connection surface will be cleaned with a high-pressure water gun at a pressure of 0.6MPa to ensure cleanliness and bonding performance. Low-hydrogen welding rods that meet national standards are used for welding connections. The welding current, voltage and welding speed are accurately adjusted according to the material and thickness of the pile steel to ensure that the weld is full, uniform, and free of pores and cracks. After the connection is completed, an appearance inspection and dimensional review are carried out, and the dimensional deviations of various dimensions are controlled within ±1.5mm to ensure that the quality of the pile connection meets the requirements.

[0070] Quality inspection and acceptance: After the underground pile connection construction is completed, ultrasonic detection technology is used to carry out non-destructive testing of the pile connection part. The detection frequency is 1.5MHz. By analyzing the ultrasonic reflection wave signal, no defects are found inside the pile connection part. At the same time, the low-strain detection method is used to apply an impact force of 20kN to the top of the pile, measure the propagation of the pile body stress wave, verify the integrity of the pile connection part, and test the pile length range to cover the entire pile connection part and the pile body 2.5m above and below to ensure that the pile connection part is well connected with the original pile body and has strong integrity. After completing the construction of 50 pile foundations, a static load test was carried out on the entire pile foundation in accordance with the design requirements. A step-by-step loading method was adopted with a loading amount of 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 load changes in real time, and load-settlement curves were drawn. The bearing capacity of the pile foundation was judged to meet the design requirements based on the curve characteristics and relevant specifications and standards. 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. There are no important buildings and complex underground pipelines around it, 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 deep hard plastic clay. The groundwater level is low, 8-10 meters below the surface.

[0073] Construction process:

[0074] Geological survey: Through high-precision geological radar and deep drilling, the soil layer distribution and physical and mechanical parameters were identified in detail, and accurate geological profiles and parameter charts were drawn. The internal friction angle of the miscellaneous fill layer is 18° (considering the complexity of its composition, the comprehensive average value is taken), the cohesion is 10kPa, and the compression modulus is 3MPa. The internal friction angle of the hard plastic clay layer is 25°, the cohesion is 30kPa, and the compression modulus is 8MPa. The groundwater level is relatively stable, about 9 meters below the surface.

[0075] Pile material inspection: Strict quality control is carried out on prestressed high-strength concrete pipe piles. The pile body 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, and the verticality deviation is 0.9 thousandths of the pile length. The pile joints are tested by simulating 1.4 times the design load to ensure that their various performance requirements meet the requirements.

[0076] Construction equipment debugging: The various systems of the static pressure pile driver are finely debugged. The pressure sensor accuracy reaches ±0.04MPa, the flow tester accuracy is ±0.09L / min, the hydraulic components have no leakage and jamming, the pressure gauge is calibrated and the measurement error is controlled within ±0.18% of the full scale, and the verticality deviation of the pile driver is within 1.6 thousandths.

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

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

[0079] Set up anti-squeezing ditches and drainage facilities: set up anti-squeezing ditches with a depth of 1.7m and a width of 0.8m around the pile sinking area, and control the flatness error of the ditch wall within ±4mm. At the same time, arrange plastic drainage boards in the pile foundation construction area with a spacing of 1.7m, arranged in a plum blossom shape, and a depth of 10m. Set up 2 rows around the pile sinking area to accelerate the dissipation of pore water pressure and reduce soil squeezing effect.

[0080] Setting up isolation piles and monitoring measures: Since there are no important facilities in the surrounding area, isolation piles are not set up. However, during the piling process, high-precision total stations and levels are used to monitor the first piles driven in. The monitoring frequency is once every 20 minutes to timely grasp the floating and tilting of the piles. When the displacement of the pile top exceeds 30mm, re-pressure measures are immediately taken to correct it.

[0081] Pre-drilling reduces resistance: pre-drill holes at the pile location, with the diameter of the hole being 70mm smaller than the pile diameter. For a 30m long pile, the drilling depth is 13m, and the verticality deviation of the hole is controlled within 3.5 thousandths. During construction, drilling is carried out as the pile is being drilled, which effectively reduces the side wall resistance and improves the pile sinking efficiency by about 25%.

[0082] Lubricant coating on the pile body: Apply high-efficiency lubricant evenly on the surface of the pile body with a coating thickness of 2.2mm. Use automated spraying equipment combined with manual assistance to ensure that the lubricant is evenly applied, reduce the pile-soil friction coefficient by about 30%, and improve the smoothness and efficiency of pile sinking.

[0083] Optimize pile tip design: According to geological conditions, a flat-bottomed pile tip is selected, and a cutting edge is set 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 sinking efficiency and pile body stability.

[0084] Underground pile connection construction: In case of underground pile breakage during the construction process, manual work and small machinery are used to clean the broken pile parts, grind the connection parts to make their roughness reach Ra3.5μm, and use a high-pressure water gun to clean the connection surface at a pressure of 0.5MPa. Then, select connectors and bolts that meet the design bearing capacity requirements for mechanical connection, tighten according to the specified torque value, and control the torque error within ±4N·m. After the connection is completed, conduct appearance inspection and dimensional review, and control the dimensional deviation within ±1.8mm to ensure that the quality of the pile connection meets the requirements.

[0085] Quality inspection and acceptance: After the construction of underground pile connection is completed, ultrasonic detection technology is used to conduct non-destructive testing of the connection pile part. The detection frequency is 1.3MHz. No defects are found inside the connection pile part. At the same time, the low-strain detection method is used to apply an impact force of 18kN on the pile top to measure the propagation of the pile body stress wave to verify the integrity of the connection pile part. The detection pile length covers the entire connection pile part and the pile body 2m above and below to ensure that the connection pile part is well connected with the original pile body and has strong integrity. After the construction of 80 pile foundations is completed, high-strain detection is carried out on the entire pile foundation in accordance with the design requirements. By applying a transient impact force of 30kN on the pile top, the strain and acceleration response of the pile body are measured using strain gauges and accelerometers, and the response data is analyzed to evaluate the integrity and bearing capacity of the pile foundation. The results show that the quality and stability of the pile foundation meet the engineering design and use requirements, providing a solid and reliable foundation guarantee for the construction of industrial plants.

[0086] The above is a schematic description of the present invention and its implementation methods, which is not restrictive. The drawings are only one of the implementation methods of the present invention, and the actual method is not limited thereto. Therefore, if a person skilled in the art is inspired by it and does not deviate from the purpose of the invention, he or she can design a structure and an embodiment similar to the technical solution without creativity, which should fall within the protection scope of the present invention.

Claims

1. A prestressed high-strength concrete pipe pile static pressure pile structure, characterized in that: It 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 a pile body is arranged at the bottom of the connecting mechanism; the adjusting mechanism comprises a fixed frame, the top of the fixed frame is fixedly connected with a first motor, the output end of the first motor is fixedly connected with a threaded rod, 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 slidably connected with a sliding sleeve; The hydraulic mechanism includes a vertical plate, and the two vertical plates are respectively fixedly connected to the threaded sleeve and the sliding sleeve surface, a horizontal plate is fixedly connected between the vertical plates, and a first hydraulic telescopic rod is penetrated on the top of the horizontal plate, and the rotating mechanism includes a box body, the top of the box body 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 box body cavity, and the output end of the second motor is fixedly connected to the first gear, the bottom of the box body is movably connected to the vertical rod through a bearing, and the top of the vertical rod is fixedly connected to the second gear, and the first gear is meshed with the second gear, and the connecting mechanism includes a connecting plate The connecting plate is fixed to the bottom of the vertical rod, the bottom of the connecting plate is fixedly connected with a connecting sleeve, the inner wall of the connecting sleeve is fixedly connected with a clamping plate, the top of the pile body extends to the inner cavity of the connecting sleeve, the bottom of the clamping plate is fixedly connected with a plug plate, the top of the pile body is provided with a slot for use with the plug plate, both sides of the connecting sleeve are fixedly connected with support plates, the surface of the support plate is penetrated by a second hydraulic telescopic rod, the output end of the second hydraulic telescopic rod is fixedly connected with a moving plate, the opposite side of the moving plate is fixedly connected with a fixed block, and the top of both sides of the pile body is provided with fixing grooves for use with the fixed block.

2. A prestressed high-strength concrete pipe pile static pressure pile structure according to claim 1, characterized in that: Both sides of the top of the base are fixedly connected with matching grooves, and the inner cavity of the counterweight groove is provided with a counterweight block.

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

4. The construction method of a prestressed high-strength concrete pipe pile static pressure pile structure according to claim 1, characterized in that: The following steps are involved: Step 1: Geological survey: Use advanced geological exploration equipment, high-precision geological radar and deep drilling to conduct a comprehensive, detailed and in-depth survey of the construction site, accurately determine the thickness, type, distribution range and physical and mechanical parameters of each soil layer, including but not limited to internal friction angle, cohesion, compression modulus, and record in detail the depth of the groundwater level and its changes with seasons and climate factors; Step 2: Pile material inspection: Based on relevant national standards and strict design requirements, we implement all-round and high-precision quality control on prestressed high-strength concrete pipe piles. At the same time, we test the sealing, connection firmness and force transmission performance of the pile joints. Through tests simulating actual stress conditions, we verify the reliability and stability of the joints when bearing the design load to ensure that they meet the requirements of construction and long-term use. Step 3: Construction equipment debugging: Carry out comprehensive, in-depth and meticulous debugging and inspection of the static pressure pile driver to ensure that all systems of the pile driver operate stably and have reliable performance during the construction process, providing a solid guarantee for the smooth progress of the pile sinking operation; Step 4: Reasonably plan the sequence of pile driving: comprehensively consider the topography, geological conditions and surrounding environmental factors of the construction site, scientifically divide the entire construction area into several small areas with moderate areas and regular shapes, and use a combination of zoned pile driving and skip driving in each small area to ensure that the soil has enough time to adjust stress and consolidate during the process of the pile body 7 being buried, thereby effectively reducing the risk of soil squeezing effect and floating deviation of the pile body; Step 5: Control the pile sinking speed: During the pile sinking process, the pile sinking speed is strictly controlled according to the geological survey report and the actual situation on site. At the same time, the pile sinking speed is dynamically adjusted according to the depth of the pile into the soil 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 excessive deformation of the soil caused by the untimely dissipation of pore water pressure, the number of piles per day is strictly controlled not to exceed 3, and the number of consecutive days of pile sinking in the same area shall not exceed 5 days in total, to ensure the stability of the soil and the quality of the pile body during the construction process; Step 6. Set up anti-crowding ditches and drainage facilities: around the pile sinking area, reasonably set up anti-crowding ditches according to the geological conditions of the site and the distribution of surrounding buildings and underground pipelines. The depth of the anti-crowding ditch 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 finishing to ensure the flatness and stability of the ditch wall, so that it can effectively release soil stress, block the stress transmission path caused by soil squeezing, and protect surrounding facilities from the impact of soil squeezing. At the same time, in the pile foundation construction area, set up sand wells or plastic drainage boards at a certain spacing and layout; Step 7. Set up isolation piles and monitoring measures: around the buildings or underground facilities that are affected, reasonably select and set up isolation measures such as pile rows, jet grouting piles or anti-seepage walls, and concrete underground continuous walls according to their structural type, foundation form, and distance from the pile-sinking area. During the piling process, use high-precision total stations and levels to conduct real-time and continuous monitoring of the piles driven first, with a monitoring frequency of no less than once every 20 minutes, so as to timely grasp the floating and tilting conditions of the piles; Step 8. Pre-drilling to reduce resistance: At the pile position, use professional drilling equipment to pre-drill. The diameter of the drill hole is determined to be 60-100mm smaller than the pile diameter according to the pile diameter. The drilling depth is reasonably determined to be 1 / 3-1 / 2 of the pile length according to the pile length and geological conditions. That is, for a 30m long pile, the drilling depth is controlled between 10-15m. During the drilling process, the verticality deviation of the drill hole is strictly controlled to not exceed 0.4% to ensure the concentricity of the drill hole and the pile position. Step 9: Apply lubricant to the pile body: Apply specially developed high-efficiency lubricant evenly on the surface of the pile body, and control the coating thickness between 2-3mm to ensure that a stable lubricating film can be formed at the pile-soil interface during the process of the pile body entering the soil, effectively reducing the friction coefficient between the pile and the soil. During the coating process, use automated spraying equipment combined with manual assistance to ensure the uniformity and integrity of the lubricant coating, avoid missing coating or uneven thickness, so as to give full play to its role in reducing side wall resistance and improve the smoothness and efficiency of pile sinking; Step 10: Optimize the pile tip design: Based on the detailed geological survey data of the construction site, combined with the characteristics of the pile type and design requirements, carry out targeted optimization design of the pile tip; Step 11, underground pile connection construction: When underground piles are broken during the construction process, the construction should be suspended immediately and the broken pile parts should be inspected and evaluated in detail. First, the soil, debris and loose concrete fragments around the broken pile parts should be carefully cleaned by manual and small machinery to ensure that the cross section of the broken pile is clearly visible and free of residual impurities. Then, professional grinding tools should be used to finely grind the connection parts of the broken piles to make their surface flat and rough to meet the design requirements. High-pressure water guns should be used to thoroughly clean the connection surfaces to remove dust and oil on the surface to ensure the cleanliness and bonding performance of the connection surfaces. Then, suitable special pile connection connectors should be selected to ensure that the welds are full, uniform, and free of pores and cracks. After the connection is completed, the connection parts should be visually inspected and the dimensions reviewed to ensure that the quality of the pile connection meets the relevant standards and design requirements. Step 12, quality inspection and acceptance: After the underground pile connection construction is completed, the connection pile part shall be promptly subjected to non-destructive testing. When ultrasonic testing technology is used, the detection probe shall be arranged in accordance with relevant standards and specifications, and the weld or connection part shall be fully scanned. The detection frequency shall not be less than 1.2MHz. By analyzing the reflected wave signal of the ultrasonic wave, it is determined whether there are defects inside the connection pile part to ensure the internal quality of the connection pile. At the same time, the low-strain detection 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 connection pile part. The detected pile length range shall cover the entire connection pile part and a certain length of the pile body above and below to ensure that the connection pile part is well connected with the original pile body and has strong integrity. In addition, after completing a certain number of pile foundation construction, according to According to the design requirements and relevant specifications, the entire pile foundation is subjected to static load test or high strain detection. The static load test adopts a step-by-step loading method, and the loading amount is determined according to the multiple of the design load. During the loading process, high-precision displacement sensors and pressure sensors are used to monitor the settlement and load changes of the pile top in real time, and the load-settlement curve is drawn. According to the curve characteristics and relevant specifications and standards, it is judged whether the bearing capacity of the pile foundation meets the design requirements. The high strain test applies a transient impact force to the pile top, and uses 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 to ensure that the quality and stability of the entire pile foundation meet the engineering design and use requirements, providing a solid and reliable foundation guarantee for subsequent engineering construction.

5. The construction method of a prestressed high-strength concrete pipe pile static pressure pile structure according to claim 4, characterized in that: In the step 1, these data are systematically analyzed and organized through professional geological analysis software, and geological profiles and related parameter charts accurate to the millimeter level are drawn, providing a detailed and reliable geological basis for the formulation of subsequent construction plans.

6. The construction method of a prestressed high-strength concrete pipe pile static pressure pile structure according to claim 4, characterized in that: In the step 2, advanced ultrasonic detectors and total station equipment are used to perform non-destructive testing on the strength of the pile body to ensure that it reaches the designed strength level and the strength distribution is uniform, and the strength deviation is controlled within ±3% of the designed strength; the dimensions of the pile body are accurately measured, including diameter, wall thickness, and length; and professional verticality detection tools are used to ensure that the verticality of the pile body meets the specification requirements and the deviation does not exceed one thousandth of the pile length.

7. The construction method of a prestressed high-strength concrete pipe pile static pressure pile structure according to claim 4, characterized in that: In the step three, for the hydraulic system, high-precision pressure sensors and flow testers are used to check whether the pressure and flow of the hydraulic oil are stable and meet the working requirements of the pile driver, and the sealing and flexibility of each hydraulic component such as the oil pump, oil cylinder, control valve, etc. are tested to ensure that there is no leakage and jamming; the pressure gauge is calibrated with high precision to control its measurement error within a very small range to accurately reflect the pressure changes during the process of the pile body being buried in the soil; the verticality control system is accurately debugged through a laser calibration device and an electronic level to ensure that the pile driver can automatically adjust the verticality of the pile body in real time during the pile sinking process to keep it within the allowable deviation range at all times.

8. The construction method of a prestressed high-strength concrete pipe pile static pressure pile structure according to claim 4, characterized in that: The sand well in step six adopts a circular steel pipe with a diameter of 0.4m as the well wall, and is filled with well-graded medium-coarse sand as filter material. The arrangement spacing is 1.6-2.0m, arranged in a plum blossom shape, and the depth reaches about 10m. Two or three rows are arranged around the pile sinking area to further reduce the adverse effects of the soil squeezing effect on the soil and pile body by accelerating the dissipation of pore water pressure.

9. The construction method of a prestressed high-strength concrete pipe pile static pressure pile structure according to claim 4, characterized in that: During the construction in step eight, the drilling-as-you-go method 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 side wall of the pile body 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 structure according to claim 4, characterized in that: In the step 10, for the 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 to be between 40° and 60° according to the mechanical properties of the soil layer and the pile diameter, and the length of the pile tip is 1.2-2.0 times the pile diameter. Through the soil squeezing and breaking effects of the conical pile tip, the pile body can more easily penetrate the upper soft soil and enter the lower hard soil layer; for the situation 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, with a cutting edge angle of 25°-45° and a width of 15-30mm, so as 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 sinking efficiency and the stability of the pile body.

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