Construction method of super-high-strength prestressed pipe pile under complex geology

Abstract

The application discloses a construction method of super-high-strength prestressed pipe pile under complex geology, which adopts a single pile vertical bearing capacity calculation strategy to review according to a preset pile type, each rock and soil parameter suggested value in a geological exploration report, a predicted pile length range and a preset hole depth to obtain a target pile length range; a hole diameter is calculated in combination with the preset pile type; long pile length and short pile length are selected in the target pile length range to determine corresponding test positions and hole depths; according to the above diameter and depth parameters, a hole hammering pile sinking process is adopted to perform super-high-strength prestressed pipe pile construction at the test positions, and test pile construction data is recorded; pile body integrity and single pile bearing capacity detection is performed on the constructed pile to obtain pile detection data, and target construction data is obtained based on the test pile and detection data. The application can quickly determine effective construction data through early calculation and test pile verification, and improve the construction efficiency and construction quality of the super-high-strength prestressed pipe pile under complex geology.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, and in particular to a method for constructing ultra-high strength prestressed pipe piles under complex geological conditions. Background Technology

[0002] Ultra-high strength prestressed concrete pipe piles (UHC) refer to a new generation of prestressed pipe piles prepared using ultra-high performance concrete (UHPC / RPC) technology, with a concrete strength grade of not less than C105, and possessing both ultra-high durability and excellent toughness. Their single-pile vertical bearing capacity characteristic value is far higher than that of ordinary high-strength prestressed concrete pipe piles (PHC). Currently, national and industry standards provide few regulations on the pre-drilling parameters for the pre-drilling and hammer-driving pile driving process. There are also few construction cases of UHC in complex geological conditions. This makes it difficult to provide sufficiently reasonable pre-drilling parameters during the design phase for UHC processes that require pre-drilling and hammer-driving due to geological reasons. A significant amount of time and resources must be invested in the design and test pile stage, and complex test pile data analysis is needed to determine the pre-drilling and driving parameters. This results in problems such as low construction efficiency and unstable construction quality in the construction of UHC using this type of technology. Summary of the Invention

[0003] This invention provides a construction method for ultra-high strength prestressed pipe piles in complex geological conditions, aiming to solve the problems of low construction efficiency and unstable construction quality in the construction of ultra-high strength prestressed pipe piles in complex geological conditions in the prior art.

[0004] This invention provides a method for constructing ultra-high strength prestressed concrete pipe piles under complex geological conditions, comprising: Based on the preset pile type, the suggested values ​​of various soil and rock parameters in the geological survey report, the estimated pile length range and the preset borehole depth, the preset single pile vertical bearing capacity calculation strategy is used for verification to obtain the target pile length range. The borehole diameter is determined based on the preset pile type and the preset borehole diameter calculation strategy; Within the target pile length range, select long pile length and short pile length, and plan the long pile test location corresponding to the long pile length and the short pile test location corresponding to the short pile length according to the geological profile map in the geological survey report. The depth of the long pile pilot hole at the long pile test location and the depth of the short pile pilot hole at the short pile test location are determined according to the preset hole depth adjustment strategy. Based on the borehole diameter, the borehole depth of the long pile, and the borehole depth of the short pile, the ultra-high strength prestressed pipe piles are constructed at the test locations of the long pile and the short pile using the borehole hammer driving pile technology, and the test pile construction data are recorded. The pile integrity and single pile bearing capacity of the completed piles at the long pile test location and the short pile test location are tested to obtain pile test data, and the target construction data are obtained based on the test pile construction data and the pile test data.

[0005] This invention provides a method for constructing ultra-high strength prestressed concrete pipe piles in complex geological conditions. The method involves using a single-pile vertical bearing capacity calculation strategy to verify the target pile length range based on a pre-defined pile type, suggested values ​​of various geotechnical parameters from the geological survey report, an estimated pile length range, and a pre-defined pilot hole depth. The pilot hole diameter is calculated using the pre-defined pile type. Within the target pile length range, long and short pile lengths are selected, and their corresponding test locations and pilot hole depths are determined. Based on the aforementioned hole diameter and depth parameters, ultra-high strength prestressed concrete pipe piles are constructed at the test locations using a pilot hole hammer driving technique, and the test pile construction data is recorded. After construction, the pile integrity and single-pile bearing capacity are tested to obtain pile test data. Based on the test pile and test data, the target construction data is obtained. This invention, through preliminary calculations and test pile verification, can quickly determine effective construction data, improving the construction efficiency and quality of ultra-high strength prestressed concrete pipe piles in complex geological conditions. Attached Figure Description

[0006] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0007] Figure 1 This is a flowchart illustrating a construction method for ultra-high strength prestressed pipe piles under complex geological conditions, provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of a sub-process of a construction method for ultra-high strength prestressed pipe piles in complex geological conditions, provided by an embodiment of the present invention. Detailed Implementation

[0008] 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, not all, of the embodiments of the present invention. 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.

[0009] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0010] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0011] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0012] Please see Figure 1 and Figure 2 , Figure 1 This is a flowchart illustrating a construction method for ultra-high strength prestressed pipe piles under complex geological conditions, provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of a sub-process of a construction method for ultra-high strength prestressed pipe piles in complex geological conditions, provided by an embodiment of the present invention.

[0013] like Figure 1 As shown, the construction method for ultra-high strength prestressed pipe piles under complex geological conditions provided by the embodiments of the present invention includes steps S11 to S16.

[0014] S11. Based on the preset pile type, the suggested values ​​of various soil and rock parameters in the geological survey report, the estimated pile length range, and the preset borehole depth, the preset single pile vertical bearing capacity calculation strategy is used for verification to obtain the target pile length range.

[0015] In this embodiment, complex geology can be understood as engineering geology with high heterogeneity, namely, engineering geology characterized by large undulations in the bearing stratum, softening of rock strata upon contact with water, high hardness of the bearing stratum rock, and shallow groundwater depth. When constructing ultra-high strength prestressed concrete pipe piles under complex geology, ensuring that the characteristic value of the vertical bearing capacity of a single pile meets the design requirements necessitates higher standards for the design and construction control of the pile driving process. Before trial pile construction during the design phase, a pre-set single pile vertical bearing capacity calculation strategy is used for verification based on the preset pile type, the suggested values ​​of various soil and rock parameters in the geological survey report, the estimated pile length range, and the preset pilot hole depth. This verification allows for the selection of a target pile length range from the estimated pile length range that can ensure the characteristic value of the vertical bearing capacity of a single pile meets the design requirements under the preset pilot hole depth.

[0016] Specifically, the formula corresponding to the calculation strategy for the vertical bearing capacity of a single pile is as follows: , where R a q represents the characteristic value of the vertical bearing capacity of a single pile. sa Let q be the characteristic value of the skin friction resistance on the pile side in the i-th soil layer. When calculating this value, the influence of groundwater after the borehole is reached on the characteristic value of the skin friction resistance should be considered. Therefore, empirical values ​​of the characteristic value of the skin friction resistance from the recommended values ​​of various soil and rock parameters should be selected. pa The characteristic value of the end resistance of the bearing stratum at the pile tip can be an empirical value corresponding to the end resistance characteristic value of the bearing stratum in the geological survey report; i Let A be the length of the pile in the i-th soil layer, determined jointly based on the soil layer profile, pile length, and borehole depth in the geological survey report; u is the outer perimeter of the pile body, and A p The cross-sectional area of ​​the pile can be directly calculated from the pile diameter based on the preset pile type, where u and A are the cross-sectional areas. p .

[0017] S12. Determine the pilot hole diameter based on the preset pile type and the preset hole diameter calculation strategy.

[0018] In this embodiment, the pile hole formed by the subsequent pilot hole should not be too large. If the diameter of the pile hole is too large, the frictional force of the hole wall will not be able to resist the self-weight of the pile. If the pipe pile is spliced ​​under this condition, after the steel wire rope holding the pipe pile is released, the weld will immediately be under tension and form micro-cracks. As a result, the final pile integrity at the weld joint position will not meet the Class I pile standard, thus affecting the pile integrity. Therefore, the pilot hole diameter is determined by a preset pile type and hole diameter calculation strategy to ensure that the pipe pile and the hole wall maintain sufficient friction.

[0019] In one embodiment, step S12 includes: The pile diameter is determined based on the preset pile type; The maximum borehole diameter is obtained by multiplying the pile diameter by a preset multiple; wherein the preset multiple is 0.70 to 0.80. The aperture diameter is determined based on the pre-selected aperture device type and the maximum aperture.

[0020] In this embodiment, when using long spiral drill rod rigs or rotary drilling rigs for pre-drilling operations, the pre-drilling hole diameter is small and the length-to-diameter ratio is large. Even slight deviations in drill rod verticality can lead to hole enlargement. Therefore, to ensure that the characteristic value of pile side friction is not significantly weakened, and to guarantee the pile foundation bearing capacity and minimize pre-drilling operation errors, the pre-drilling hole diameter should be controlled at 0.70 to 0.80 times the pile diameter. Specifically, 0.70 to 0.80 times the preset pile diameter is taken as the maximum hole diameter. Based on the pre-selected pre-drilling equipment type, the pre-drilling hole diameter is further determined from the maximum hole diameter, thereby determining the diameter of the drill rod or hole-forming device used in actual construction. For example, when using a long spiral drill rod machine, the maximum hole diameter needs to be further reduced to determine the pilot hole diameter. When the preset pile type is UHC600 (130) AB pile, the pile diameter is 600mm. The preset multiple is 0.80, and the maximum hole diameter is calculated to be 480mm. Further reduction can be made to select 450mm as the pilot hole diameter, that is, the drill rod diameter of the long spiral drill rod machine is selected as 450mm.

[0021] S13. Select the long pile length and short pile length within the target pile length range, and plan the long pile test location corresponding to the long pile length and the short pile test location corresponding to the short pile length according to the geological profile map in the geological survey report.

[0022] In this embodiment, a long pile length and a short pile length are selected from the target pile length range determined in step S11. Specifically, a target pile length exceeding a preset pile length threshold can be randomly selected from the target pile length range as the long pile length, and a target pile length not exceeding the preset pile length threshold can be randomly selected as the short pile length. Preferably, the preset pile length threshold is 20m. Alternatively, a target pile length close to the upper limit can be selected as the long pile length, and a target pile length close to the lower limit can be selected as the short pile length; no specific limitation is made here. Before pile testing in complex geological conditions, based on the bearing layer elevation in the geological profile map of the geological survey report, the test locations for the long pile and short pile lengths are planned respectively. This facilitates subsequent pile testing and pile formation testing at the long pile and short pile test locations, thereby verifying the single pile vertical bearing capacity characteristic value of the selected long pile length and short pile length.

[0023] S14. Determine the long pile pilot hole depth at the long pile test location and the short pile pilot hole depth at the short pile test location according to the preset hole depth adjustment strategy.

[0024] In this embodiment, a pre-drilling and subsequent pile driving process is adopted under complex geological conditions. Due to the large heterogeneity of the geology, the estimated pile length in the geological survey report usually varies greatly. The conventional practice of determining the pre-drilling depth, which directly uses a single preset pre-drilling depth given in the geological survey report, is often unsuitable when the estimated pile length varies greatly. To improve the applicability of the pre-drilling depth parameters, different pre-drilling parameters need to be used for different pile lengths. Furthermore, the pre-drilling depth has a significant impact on the pile driving depth. If the pre-drilling is too deep, excessive pile side friction may occur, resulting in a pile driving depth less than the pre-drilling depth and thus a failed pile. If the pre-drilling depth is too shallow, the pile driving depth may be less than the design effective pile length, resulting in a pile length that does not meet the design requirements. Therefore, before test piles under complex geological conditions, the pre-drilling depths for long pile test locations and short pile test locations are calculated separately according to the hole depth adjustment strategy. Setting different pre-drilling depths for long pile length and short pile length is beneficial to improving the construction quality of the pipe piles.

[0025] In one embodiment, step S14 includes: Calculate the depth required to enter a predetermined depth within the bearing stratum corresponding to the test location of the long pile, and obtain the depth of the long pile pilot hole; wherein, the predetermined depth is 1~2m; The difference between the length of the short pile and the preset length is calculated to obtain the depth of the short pile pilot hole; wherein the preset length is 1~3m.

[0026] In this embodiment, for the long pile test location corresponding to the long pile length, the long pile pilot hole depth is set to the depth required to penetrate a preset depth into the bearing stratum. This can also be understood as the long pile pilot hole depth satisfying: H = h1 + h2; where H is the long pile pilot hole depth, h1 is the depth from the ground surface to the top surface of the bearing stratum, and h2 is the preset depth, which is 1~2m. For the short pile test location corresponding to the short pile length, the short pile pilot hole depth is set to the short pile length minus the difference of 1~3m.

[0027] S15. Based on the borehole diameter, the long pile borehole depth, and the short pile borehole depth, use the borehole hammer driving pile technology to construct ultra-high strength prestressed pipe piles at the long pile test location and the short pile test location respectively, and record the test pile construction data.

[0028] In this embodiment, the validity of the determined pilot hole diameter and depth are verified through test pile construction. Specifically, based on the pilot hole diameter and the pilot hole depth for long piles, ultra-high strength prestressed concrete pipe piles are constructed at the test locations of long piles using the pilot hole hammer driving technique, and the corresponding construction data is recorded simultaneously. Furthermore, based on the pilot hole diameter and the pilot hole depth for short piles, ultra-high strength prestressed concrete pipe piles are constructed at the test locations of short piles using the pilot hole hammer driving technique, and the corresponding construction data is recorded simultaneously. The construction data corresponding to the test locations of long piles and short piles are combined to form the test pile construction data. The pilot hole hammer driving technique includes pilot hole construction and pile driving construction. Pile driving construction includes lifting and inserting piles, hammer driving piles, welding and splicing piles, and pile driving.

[0029] Furthermore, during the construction of ultra-high strength prestressed concrete pipe piles, if the pile driving depth is less than the pilot hole depth, or if a suspended pile appears, it indicates that the corresponding pilot hole depth is too large, and the pilot hole depth should be reduced according to the suspension height. If the effective pile length exceeds the corresponding long pile length or short pile length but still cannot reach the hammer-stopping standard, it indicates that the corresponding pilot hole depth is too large, and the corresponding pilot hole depth should be appropriately reduced. If, after the pile driving and hammer-stopping are completed, the effective pile length is less than the corresponding long pile length or short pile length, it indicates that the corresponding pilot hole depth is too small, and the corresponding pilot hole depth should be appropriately increased.

[0030] In one embodiment, step S15 includes: S151. Based on the borehole diameter, the long pile borehole depth, and the short pile borehole depth, borehole equipment is used to construct boreholes at the long pile test location and the short pile test location to form corresponding pile holes, and the borehole construction data is recorded. S152. Using a hammer-driving method, long piles and short piles are driven into the pile holes corresponding to the long pile test positions and the short pile test positions, respectively, and the driving data for the long piles and the short piles are recorded. The long pile is an ultra-high strength prestressed pipe pile that meets the preset pile type and length requirements; the short pile is an ultra-high strength prestressed pipe pile that meets the preset pile type and length requirements. S153. The test pile construction data is composed of the pilot hole construction data, the long pile driving data and the short pile driving data.

[0031] In this embodiment, based on the borehole diameter and the borehole depth for long piles, borehole drilling equipment is used to construct boreholes at the long pile test location. Similarly, based on the borehole diameter and the borehole depth for short piles, borehole drilling equipment is used at the short pile test location. During the borehole drilling process, the verticality of the borehole drill rod is strictly controlled to avoid excessive hole enlargement. This ensures the formation of corresponding pile holes at both the long and short pile test locations, and borehole drilling data is recorded simultaneously. The borehole drilling data includes the actual borehole diameter and actual depth to facilitate analysis of the impact of borehole parameters on pile integrity and pile length. Additionally, a hole cleaning process can be performed after the pile holes are formed, during which the drill bit is lifted 10-20 cm from the bottom of the hole and allowed to idle. Piling operations are then carried out promptly after the boreholes are formed. The long and short piles are driven into the corresponding pile holes using a hammer method, and the driving data for both long and short piles is recorded simultaneously. The piling construction includes hoisting and inserting piles, hammering and driving piles, welding and splicing piles, and driving piles into the ground. Data for both long and short piles includes the number of hammer blows required to drive the pipe pile 1 meter, the drop height of the pile hammer, and the penetration depth of the final three hammer blows. The data from the pilot hole construction, long pile driving, and short pile driving are combined to form test pile construction data, which will be used in conjunction with subsequent pile completion testing data to determine the construction data required for effective pile formation.

[0032] Furthermore, three long piles and three short piles can be selected for test pile construction. Based on the borehole diameter, the borehole depth of the long pile, and the borehole depth of the short pile, three corresponding pile holes are formed at the test locations of the long pile and the short pile. During the implementation process, the borehole depth of each pile hole can be finely adjusted to increase the control.

[0033] In one embodiment, both the long pile and the short pile are equipped with an integrated pile tip.

[0034] In this embodiment, the complex geology is highly heterogeneous, characterized by large undulations in the bearing layer, softening of rock strata upon contact with water, high hardness of the bearing layer rock strata, and shallow groundwater depth. To ensure successful pile formation, both the selected long and short piles are equipped with integrated pile tips.

[0035] In one embodiment, the long pile includes several sections of pipe piles. During the pile driving process of the long pile, the pile joints of adjacent pipe piles are connected by a combination of mechanical engagement and welding.

[0036] In this embodiment, the construction of ultra-high strength prestressed concrete pipe piles is carried out under complex geological conditions. Because the designed vertical bearing capacity of a single pile is much higher than that of ordinary high-strength prestressed concrete pipe piles, the impact force during hammer driving is greater, making the pile joints more prone to defects. Especially when the pile needs to withstand pull-out forces, the pile joints need to be improved from the traditional single mechanical engagement joint to a mechanical engagement plus welding structure to ensure the integrity of the pile body. Therefore, during the pile driving process of long piles, the pile joints of adjacent pipe piles are connected by a combination of mechanical engagement and welding, which helps to reduce the impact of improper pile joint design on the integrity of the pile body. Similarly, during the pile driving process of short piles, the pile joints of adjacent pipe piles are also connected by a combination of mechanical engagement and welding.

[0037] In one embodiment, pile driving is carried out within a preset time period after the corresponding pile holes are formed at the long pile test location and the short pile test location.

[0038] Furthermore, the preset duration does not exceed 4 hours.

[0039] In this embodiment, pile driving must be carried out promptly after the pile hole is formed by the pilot hole construction. Prolonged exposure of the hole wall leads to excessive disturbance, significantly reducing the characteristic value of the pile's side friction and consequently lowering the final pile bearing capacity. Therefore, pile driving is required to be carried out within a preset timeframe after the pile hole is formed to avoid affecting the final pile bearing capacity. Specifically, the preset timeframe does not exceed 4 hours; preferably, pile driving must be completed within 4 hours of the pile hole being formed.

[0040] In one embodiment, the completion condition for the pile driving construction is that after the penetration of the last three hammer blows meets the preset hammer stopping standard, three more hammer blows are added.

[0041] In this embodiment, the construction of ultra-high strength prestressed concrete pipe piles is carried out under complex geological conditions. Due to the use of pre-drilling technology, the disturbance of some bearing strata is weakened when the pre-drilling is completed. If pile driving is stopped after the hammering reaches the stopping standard, the vertical bearing capacity of the single pile may fail to meet the design requirements. Therefore, after the hammering reaches the stopping standard, that is, after the penetration of the last three hammer blows meets the preset stopping standard, three more hammer blows are required to ensure that the vertical bearing capacity of the single pile meets the standard. Each blow consists of 10 blows.

[0042] In one embodiment, after the step of using a borehole-starting device to perform borehole construction at the long pile test location and the short pile test location respectively to form corresponding pile holes according to the borehole diameter, the long pile borehole depth, and the short pile borehole depth, the method further includes: The formed pile holes are covered with steel mesh and welded in place, and warning flags are placed at the pile holes.

[0043] In this embodiment, after the pile hole is completed, in order to ensure the safety of construction personnel and other unrelated personnel and to prevent unexpected accidents, steel mesh can be used to cover the pile hole and weld it in place. Warning flags, such as colored flags or triangular flags, can be placed at the pile hole to prevent unrelated personnel from entering the area with the pile hole.

[0044] S16. Perform pile integrity testing and single pile bearing capacity testing on the piles at the long pile test location and the short pile test location to obtain pile test data, and obtain target construction data based on the test pile construction data and the pile test data.

[0045] In this embodiment, the integrity of the pile body and the single pile bearing capacity of the piles formed after test piles at the long pile test location and the short pile test location are tested to obtain pile test data. The effectiveness of the pilot hole parameters and pile driving parameters are verified by the test pile construction data and pile test data to ensure the construction quality of precast piles. At the same time, the pilot hole and pile driving parameters for effective pile formation can be identified, that is, the target construction data required for effective pile formation can be obtained, providing a relatively accurate reference for subsequent pile construction and pile matching, improving construction efficiency and reducing pile loss. Thus, through preliminary calculation and test pile verification, effective construction data can be quickly determined, improving the construction efficiency and construction quality of ultra-high strength prestressed pipe piles under complex geological conditions.

[0046] Among them, the pile integrity test is a low-strain method, used to detect the integrity of a single pile. It involves striking the top of the pile with a hammer or force bar, applying energy to the pile and generating a longitudinal stress wave. This stress wave propagates downwards along the pile. Sensors pick up reflected signals from pile defects and different interfaces. By detecting and analyzing the propagation history of the stress wave in the pile, the integrity of the pile foundation can be analyzed. Furthermore, the nature of pile defects and the estimated pile length or defect location can be determined based on the reflected and transmitted waves generated when the pile interface changes abruptly (e.g., excessive sediment at the pile bottom, mud inclusion, fracture, diameter expansion or contraction, etc.). The strength of the concrete can be inferred from the propagation speed of the stress wave in the pile. The single pile bearing capacity test is a static load test, used to detect the vertical bearing capacity of a single pile. It involves applying axial pressure and axial uplift force to the top of the pile in stages according to its intended use, observing the settlement and uplift displacement of the corresponding test points over time, and determining the corresponding vertical bearing capacity of the single pile based on the relationship between load and displacement.

[0047] This invention discloses a construction method for ultra-high strength prestressed concrete pipe piles in complex geological conditions. The method, based on a pre-defined pile type, suggested values ​​of various geotechnical parameters from the geological survey report, an estimated pile length range, and a pre-defined pilot hole depth, employs a single-pile vertical bearing capacity calculation strategy to verify and obtain the target pile length range. The pilot hole diameter is calculated in conjunction with the pre-defined pile type. Within the target pile length range, long and short pile lengths are selected, and their corresponding test locations and pilot hole depths are determined. Based on the aforementioned hole diameter and depth parameters, ultra-high strength prestressed concrete pipe piles are constructed at the test locations using a pilot-hole hammer driving technique, and the test pile construction data is recorded. The integrity of the pile body and the single-pile bearing capacity are tested after construction, yielding pile test data. Based on the test pile and test data, the target construction data is obtained. This invention, through preliminary calculations and test pile verification, can quickly determine effective construction data, improving the construction efficiency and quality of ultra-high strength prestressed concrete pipe piles in complex geological conditions.

[0048] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A construction method for ultra-high strength prestressed pipe piles under complex geological conditions, characterized in that, include: Based on the preset pile type, the suggested values ​​of various soil and rock parameters in the geological survey report, the estimated pile length range and the preset borehole depth, the preset single pile vertical bearing capacity calculation strategy is used for verification to obtain the target pile length range. The borehole diameter is determined based on the preset pile type and the preset borehole diameter calculation strategy; Within the target pile length range, select long pile length and short pile length, and plan the long pile test location corresponding to the long pile length and the short pile test location corresponding to the short pile length according to the geological profile map in the geological survey report. The depth of the long pile pilot hole at the long pile test location and the depth of the short pile pilot hole at the short pile test location are determined according to the preset hole depth adjustment strategy. Based on the borehole diameter, the borehole depth of the long pile, and the borehole depth of the short pile, the ultra-high strength prestressed pipe piles are constructed at the test locations of the long pile and the short pile using the borehole hammer driving pile technology, and the test pile construction data are recorded. The pile integrity and single pile bearing capacity of the completed piles at the long pile test location and the short pile test location are tested to obtain pile test data, and the target construction data are obtained based on the test pile construction data and the pile test data.

2. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 1, characterized in that, The step of determining the pilot hole diameter based on the preset pile type and preset hole diameter calculation strategy includes: The pile diameter is determined based on the preset pile type; The maximum borehole diameter is obtained by multiplying the pile diameter by a preset multiple; wherein the preset multiple is 0.70 to 0.

80. The aperture diameter is determined based on the pre-selected aperture device type and the maximum aperture.

3. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 1, characterized in that, The step of determining the long pile pilot hole depth at the long pile test location and the short pile pilot hole depth at the short pile test location according to a preset hole depth adjustment strategy includes: Calculate the depth required to enter a predetermined depth within the bearing stratum corresponding to the test location of the long pile, and obtain the depth of the long pile pilot hole; wherein, the predetermined depth is 1~2m; The difference between the length of the short pile and the preset length is calculated to obtain the depth of the short pile pilot hole; wherein the preset length is 1~3m.

4. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 1, characterized in that, The process involves constructing ultra-high strength prestressed concrete pipe piles at the test locations of the long pile and the short pile using a pre-drilled pile driving technique, based on the diameter of the pilot hole, the depth of the pilot hole for the long pile, and the depth of the pilot hole for the short pile. The test pile construction data is then recorded, including: Based on the borehole diameter, the borehole depth of the long pile, and the borehole depth of the short pile, borehole-setting equipment is used to construct boreholes at the test locations of the long pile and the short pile to form corresponding pile holes, and the borehole construction data is recorded. Piling operations were carried out on the pile holes corresponding to the long pile test location and the short pile test location using the hammer driving method, and the long pile driving data and short pile driving data were recorded. The long pile is an ultra-high strength prestressed pipe pile that meets the preset pile type and pile length; the short pile is an ultra-high strength prestressed pipe pile that meets the preset pile type and pile length. The test pile construction data is composed of the pilot hole construction data, the long pile driving data, and the short pile driving data.

5. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 4, characterized in that, Both the long pile and the short pile are equipped with an integrated pile tip.

6. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 4, characterized in that, The long pile includes several sections of pipe piles. During the pile driving process, the pile joints of adjacent pipe piles are connected by a combination of mechanical engagement and welding.

7. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 4, characterized in that, Piling construction is carried out within a preset time period after the corresponding pile holes are formed at the long pile test location and the short pile test location.

8. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 4, characterized in that, The preset duration shall not exceed 4 hours.

9. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 4, characterized in that, The completion condition for the pile driving construction is that after the penetration of the last three hammer blows meets the preset hammer stopping standard, three more hammer blows are added.

10. The construction method for ultra-high strength prestressed pipe piles under complex geological conditions according to claim 4, characterized in that, After the step of constructing pilot holes at the long pile test location and the short pile test location using pilot hole equipment according to the pilot hole diameter, the pilot hole depth of the long pile, and the pilot hole depth of the short pile to form corresponding pile holes, the method further includes: The formed pile holes are covered with steel mesh and welded in place, and warning flags are placed at the pile holes.

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