Test device for offshore wind power suction bucket jacket and method

Abstract

A test device for an offshore wind power suction bucket jacket and a method, relating to the technical field of suction bucket jackets. The test device comprises a suction bucket jacket model (400), a test soil tank (100), a multi-directional loading device (200) and a sensor assembly. The suction bucket jacket model (400) is made on the basis of equal scaling of a suction bucket jacket prototype. The suction bucket jacket model (400) comprises a jacket main body (401) and a three-bucket foundation. The test soil tank (100) comprises a tank body, which is filled with sandy soil, the sandy soil being used for installation of the three-bucket foundation of the suction bucket jacket model (400). The multi-directional loading device (200) is arranged above the test soil tank (100). The multi-directional loading device (200) comprises a vertical loading module and a horizontal loading module, the vertical loading module and the horizontal loading module respectively being used for applying a vertical load and a horizontal load to the suction bucket jacket model (400) installed in the test soil tank (100). The sensor assembly is used for collecting test data. By means of a test result of the suction bucket jacket model (400), the bearing capacity of the suction bucket jacket prototype can be reflected.

Description

A testing device and method for offshore wind power suction tube jacket

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 28, 2023, with application number 202311617666.7 and application name “Testing method based on three-degree-of-freedom loading device”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of suction tube jackets, and in particular to a testing device and method for offshore wind power suction tube jackets. Background Art

[0003] A suction tube jacket is a type of foundation commonly used for structures in oceans or rivers. It primarily supports various offshore or underwater structures, such as bridges, wind turbines, and oil and gas platforms. Typically constructed of steel, it boasts a stable structure and appropriate dimensions to withstand the challenges of the offshore environment. The primary function of an offshore suction tube jacket is to ensure the accurate positioning and stable fixation of the suction tube, allowing the pipeline or equipment to be installed to the seabed as planned.

[0004] A suction tube jacket typically consists of a jacket and a three-tube foundation. The jacket possesses sufficient strength and rigidity to withstand external forces such as waves, wind, and tidal currents, ensuring that the suction tubes are not severely deflected or damaged. The three-tube foundation typically consists of three suction tube foundations arranged in a triangular pattern, with an open bottom and a closed top. During seabed lowering operations, the suction tube foundations are firmly embedded in the seabed by pumping out seawater from the tubes to create negative pressure, eliminating the need for external forces such as piling.

[0005] In order to ensure that the design of the suction tube jacket meets the performance requirements, it is generally necessary to test the load-bearing performance of the suction tube jacket under load. However, the physical prototype of the suction tube jacket is tens of meters high and weighs hundreds or thousands of tons, making it very difficult to test the prototype of the suction tube jacket.

[0006] Summary of the Invention

[0007] In response to the deficiencies of the prior art, the present application provides a testing device and method for an offshore wind power suction tube jacket, which solves the technical problem in the prior art that the bearing performance of the suction tube jacket under load cannot be effectively tested.

[0008] In a first aspect, the present application provides a testing device for an offshore wind turbine suction tube jacket, comprising a suction tube jacket model, a test soil trough, a multi-directional loading device, and a sensor assembly. The suction tube jacket model is scaled based on a suction tube jacket prototype.

[0009] The suction tube jacket model includes a jacket body and a three-tube foundation. The three-tube foundation includes three suction tube foundations distributed in a triangle. The lower end of the suction tube foundation is open and the top end is fixedly connected to the lower end of the jacket.

[0010] The test soil trough comprises a trough body, wherein the trough body is filled with sand, and the sand is used to install the three-tube foundation of the suction tube jacket model;

[0011] The multidirectional loading device is arranged above the test soil trough, and the multidirectional loading device includes a vertical loading module and a horizontal loading module, and the vertical loading module and the horizontal loading module are respectively used to apply vertical load and horizontal load to the suction tube jacket model installed in the test soil trough;

[0012] The sensor assembly is used to collect test data; wherein, the test data includes vertical load data, horizontal load data, horizontal displacement data, inclination data of the suction tube jacket model, soil pressure data of the suction tube foundation, and strain data at the connection between the jacket body and the suction tube foundation.

[0013] Based on the above technical content, the testing device can use the suction tube jacket model to perform load-bearing performance-related tests, so that the load-bearing performance of the suction tube jacket prototype can be reflected through the test results of the suction tube jacket model, solving the problem in the existing technology that the load-bearing performance of the suction tube jacket under load cannot be effectively tested.

[0014] In a possible implementation, the lower end of the jacket body is connected to the top center of the suction tube foundation by welding through ribs.

[0015] Furthermore, this structure can be used to test the influence of the central connection structure between the jacket body and the suction tube foundation on the bearing performance of the suction tube jacket.

[0016] In a possible implementation, the lower end of the jacket body is connected to the top edge of the suction tube foundation by welding via ribs.

[0017] Furthermore, this structure can be used to test the influence of the eccentric connection structure between the jacket body and the suction tube foundation on the bearing performance of the suction tube jacket.

[0018] In a possible implementation, the sensor assembly includes a first load sensor, a second load sensor, a displacement sensor, an inclination sensor, a plurality of earth pressure cells, and a plurality of strain gauges;

[0019] The first load sensor is provided on the vertical loading module and is used to collect vertical load data applied by the vertical loading module to the suction tube jacket model;

[0020] The second load sensor is provided on the horizontal loading module and is used to collect horizontal load data applied by the horizontal loading module to the suction tube jacket model;

[0021] The displacement sensor is arranged on the horizontal loading module and is used to collect horizontal displacement data of the horizontal loading module;

[0022] The inclination sensor is arranged at the upper end of the jacket body and is used to collect inclination data of the suction tube jacket model;

[0023] The soil pressure box is arranged at the top cover and the wall of the suction cylinder foundation, and is used to collect soil pressure data of the suction cylinder foundation;

[0024] The strain gauge is provided at the connection between the jacket body and the suction cylinder foundation, and is used to collect strain data at the connection between the jacket body and the suction cylinder foundation.

[0025] Furthermore, relevant test data can be comprehensively and effectively collected through the sensor component.

[0026] In a possible implementation, the apparatus further includes a steel frame, wherein the lower portion of the steel frame is used to install the test soil trough, and the upper portion of the steel frame is provided with a crossbeam;

[0027] A horizontal guide rail is provided on the crossbeam, and a mounting connector with an adjustable mounting position is provided on the horizontal guide rail. The mounting connector is fixedly connected to the multi-directional loading device.

[0028] Furthermore, the steel frame can facilitate the installation of relevant test components.

[0029] In a possible implementation, the vertical loading module includes a vertical loading hydraulic cylinder, a vertical loading pneumatic cylinder, or a vertical loading screw, and the horizontal loading module includes a horizontal loading hydraulic cylinder, a horizontal loading pneumatic cylinder, or a horizontal loading screw.

[0030] Furthermore, the vertical loading module and the horizontal loading module can stably and accurately apply loads to the suction tube jacket model.

[0031] Second method: This application provides a method for testing an offshore wind turbine suction tube jacket, based on the offshore wind turbine suction tube jacket foundation testing device as described in the first aspect, the method comprising:

[0032] Place the suction tube jacket model at a predetermined position in the test soil trough;

[0033] Applying a vertical load to the suction tube jacket model using a vertical loading module of a multi-directional loading device to install the three-tube foundation of the suction tube jacket model in the sand of the test soil trough;

[0034] Applying a horizontal load to the suction tube jacket model using a horizontal loading module of a multi-directional loading device to perform a horizontal ultimate bearing capacity test on the three-tube foundation of the suction tube jacket model;

[0035] During the test, the sensor assembly is used to collect test data; wherein, the test data includes the vertical load data, horizontal load data, horizontal displacement data, inclination data of the suction tube jacket model, as well as the soil pressure data of the suction tube foundation and the strain data of the connection between the jacket body and the suction tube foundation.

[0036] Based on the above technical content, by analyzing the structural characteristics of the three-tube foundation during the penetration process and the experimental results of the vertical bearing characteristics of the three-tube foundation, the horizontal bearing capacity of the three-tube foundation was studied after the three-tube foundation was installed. During the test, horizontal load, horizontal displacement, inclination and strain data were recorded. The bearing capacity, failure mode and movement characteristics of the three-tube foundation when subjected to horizontal load can be studied and analyzed, which has a good reference value for the prototype of the suction tube jacket.

[0037] In one possible implementation, a vertical loading module of a multi-directional loading device is used to apply a vertical load to the suction tube jacket model so as to install the three-tube foundation of the suction tube jacket model in the sand of the test soil trough, including:

[0038] Applying a vertical load to the top centroid of the suction tube jacket model using the vertical loading module to uniformly press the suction tube foundation of the three-tube foundation into the sand in the test soil trough;

[0039] During the process of applying the vertical load, when the vertical load data reaches a preset load, the vertical loading module stops applying the vertical load.

[0040] Furthermore, a vertical load is applied to the top centroid position of the suction tube jacket model to ensure that the suction tube jacket model is vertically pressed into the sand.

[0041] In one possible implementation, a horizontal load is applied to the suction tube jacket model using a horizontal loading module of a multi-directional loading device to perform a horizontal ultimate bearing capacity test on the three-tube foundation of the suction tube jacket model, including:

[0042] Applying a horizontal load to a loading point of the suction tube jacket model using the horizontal loading module; wherein the loading point is used to ensure that when the three-tube foundation of the suction tube jacket model is subjected to the horizontal load, only one suction tube foundation of the three-tube foundation is in a tension state;

[0043] During the process of applying the horizontal load, when the reaction force of the three-tube foundation reaches a peak value and remains stable, and the sand foundation reaches its ultimate bearing capacity and is completely destroyed, the horizontal loading module stops applying the horizontal load.

[0044] Furthermore, by applying a horizontal load to the loading point of the suction tube jacket model, only one of the three-tube foundations is in a tension state, thereby ensuring the accuracy of the horizontal bearing performance test results of the suction tube jacket model.

[0045] In a possible implementation, the method further includes:

[0046] Constructing a finite element model of the suction tube jacket model;

[0047] Performing a finite element simulation test on the finite element model to obtain a finite element test result of the finite element model;

[0048] The finite element test results are compared with the test data to verify the reliability of the test data.

[0049] Furthermore, the reliability of the test data is verified through the finite element model, thus providing guidance for subsequent structural design, optimization and testing.

[0050] The present application provides a testing device and method for an offshore wind power suction tube jacket. By testing a small-scale suction tube jacket model, the testing device can use the suction tube jacket model to perform load-bearing performance-related tests, so that the load-bearing performance of the suction tube jacket prototype can be reflected through the test results of the suction tube jacket model, thereby solving the problem in the prior art of being unable to effectively test the load-bearing performance of the suction tube jacket under load. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0052] FIG1 is a schematic structural diagram of a test device for an offshore wind power suction tube jacket;

[0053] FIG2 is a schematic diagram of the arrangement of an earth pressure cell on a suction cylinder foundation;

[0054] FIG3 is a structural diagram of a suction tube jacket model;

[0055] FIG4 is a schematic structural diagram of another suction tube jacket model;

[0056] FIG5 is a partial structural diagram of a testing device for an offshore wind power suction tube jacket;

[0057] FIG6 is a flow chart of a method for testing an offshore wind power suction tube jacket;

[0058] Figure 7 is a schematic diagram of the cumulative curve of sand particle gradation;

[0059] Figure 8 is a schematic diagram of the penetration load and vertical displacement curves of the eccentrically connected three-tube foundation and the centrally connected three-tube foundation;

[0060] Figure 9 is a schematic diagram of the horizontal load-displacement curve of the eccentrically connected three-tube foundation;

[0061] Figure 10 is a schematic diagram of the horizontal load-displacement curve of the centrally connected three-tube foundation;

[0062] Figure 11 is a displacement vector diagram of the central connection suction tube jacket model after horizontal loading is completed;

[0063] Figure 12 is a displacement vector diagram of the eccentrically connected suction tube jacket model after horizontal loading;

[0064] Figure 13 is a schematic diagram of the resultant force acting on the lower compression cylinder (compression cylinder) and the upper tension cylinder (tension cylinder) in the three-cylinder foundation;

[0065] Figure 14 is a schematic diagram of the resultant moment acting on the lower compression cylinder (compression cylinder) and the upper tension cylinder (tension cylinder) in the three-cylinder foundation;

[0066] Figure 15 is a schematic diagram of the lateral earth pressure generated by the lower compression cylinder and the upper pull cylinder in the three-cylinder foundation;

[0067] Figure 16 is a schematic diagram of equivalent plastic strain of different cylinders;

[0068] Figure 17 is the displacement cloud map after ground stress equilibrium;

[0069] Figure 18 is a vertical stress cloud diagram after ground stress equilibrium;

[0070] FIG19 is a schematic diagram of the displacement-inclination curve of the eccentrically connected suction tube jacket model;

[0071] FIG20 is a schematic diagram of the displacement-inclination curve of the centrally connected suction tube jacket model;

[0072] FIG21 is a schematic diagram of the displacement-force curve of the loading point of the model test;

[0073] FIG22 is a schematic diagram of the displacement-force curve of the loading point of the finite element simulation results;

[0074] FIG23 is a schematic diagram of the plastic strain of the main structure of the jacket.

[0075] Explanation of reference numerals: 100 - test soil trough; 200 - multi-directional loading device; 300 - steel frame; 301 - crossbeam; 302 - mounting connector; 303 - horizontal guide rail; 400 - suction tube jacket model; 401 - jacket body; 402 - rib plate; 403 - suction tube foundation.

[0076] The above drawings illustrate specific embodiments of the present application, which will be described in more detail below. These drawings and the textual description are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of the present application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0077] The following will be combined with the drawings in the specification of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0078] A suction tube jacket is a type of foundation commonly used for structures in oceans or rivers. It primarily supports various offshore or underwater structures, such as bridges, wind turbines, and oil and gas platforms. Typically constructed of steel, it boasts a stable structure and appropriate dimensions to withstand the challenges of the offshore environment. The primary function of an offshore suction tube jacket is to ensure the accurate positioning and stable fixation of the suction tube, allowing the pipeline or equipment to be installed to the seabed as planned.

[0079] A suction tube jacket typically consists of a jacket and a three-tube foundation. The jacket possesses sufficient strength and rigidity to withstand external forces such as waves, wind, and tidal currents, ensuring that the suction tubes are not severely deflected or damaged. The three-tube foundation typically consists of three suction tube foundations arranged in a triangular pattern, with an open bottom and a closed top. During seabed lowering operations, the suction tube foundations are firmly embedded in the seabed by pumping out seawater from the tubes to create negative pressure, eliminating the need for external forces such as piling.

[0080] In order to ensure that the design of the suction tube jacket meets the performance requirements, it is generally necessary to test the load-bearing performance of the suction tube jacket under load. However, the physical prototype of the suction tube jacket is tens of meters high and weighs hundreds or thousands of tons, making it very difficult to test the prototype of the suction tube jacket.

[0081] In response to the above technical problems, the present application proposes a testing device for offshore wind power suction tube jackets. The testing device can be used to perform load-bearing performance-related tests using a suction tube jacket model, so that the load-bearing performance of the suction tube jacket prototype can be reflected through the test results of the suction tube jacket model, thereby solving the problem in the prior art that the load-bearing performance of the suction tube jacket under load cannot be effectively tested.

[0082] The following is a detailed description of the technical solution of the inspection system for the photothermal mirror field provided by this application through specific embodiments. It should be noted that the following embodiments can exist independently or in combination with each other, and the same or similar content may not be repeated in different embodiments.

[0083] 1 and 5 , in some embodiments, the test device for the offshore wind turbine suction tube jacket comprises a suction tube jacket model 400, a test soil trough 100, a multi-directional loading device 200 and a sensor assembly. The suction tube jacket model 400 is scaled based on the suction tube jacket prototype; the suction tube jacket model 400 comprises a jacket body 401 and a three-tube foundation, the three-tube foundation comprising three suction tube foundations 403 distributed in a triangular shape, the lower end of the suction tube foundation 403 is open and the top end is fixedly connected to the lower end of the jacket; the test soil trough 100 comprises a trough body, the trough body is filled with sand, and the sand is used to install the three-tube foundation of the suction tube jacket model 400; the multi-directional loading device 200 is arranged above the test soil trough 100, and the multi-directional loading device 200 comprises The vertical loading module and the horizontal loading module are used to apply vertical load and horizontal load to the suction tube jacket model 400 installed in the test soil trench 100 respectively; the sensor assembly is used to collect test data; wherein the test data includes the vertical load data, horizontal load data, horizontal displacement data, inclination data of the suction tube jacket model 400 and the soil pressure data of the suction tube foundation 403, and the strain data at the connection between the jacket body 401 and the suction tube foundation 403.

[0084] The multi-directional loading device 200 includes a vertical loading module and a horizontal loading module, which are respectively used to apply vertical load and horizontal load to the suction tube jacket model 400 installed in the test soil trough 100 during the subsequent test process.

[0085] Preferably, the vertical loading module includes a vertical loading hydraulic cylinder, a vertical loading pneumatic cylinder or a vertical loading screw, and the horizontal loading module includes a horizontal loading hydraulic cylinder, a horizontal loading pneumatic cylinder or a horizontal loading screw.

[0086] A hydraulic cylinder is a hydraulic actuator that converts hydraulic energy into mechanical energy, performing linear reciprocating motion (or oscillating motion). A pneumatic cylinder is similar to a hydraulic cylinder, but it converts air pressure into mechanical energy. A lead screw is a mechanical element that converts rotational motion into linear motion. All three offer the advantages of simple structure and reliable operation, and can stably and accurately apply loads to the suction tube jacket model 400.

[0087] The sensor assembly is used to collect relevant test data during the testing process. This data primarily includes vertical load data, horizontal load data, horizontal displacement data, and inclination data for the suction tube jacket model 400, as well as soil pressure data on the suction tube foundation 403 and strain data at the connection between the jacket body 401 and the suction tube foundation 403. This test data allows for the study of the displacement patterns, load sharing ratios, and the source and generation mechanism of the anti-overturning moment of each of the three suction tube foundations 403 under the action of lateral forces and moments.

[0088] Preferably, the sensor assembly includes a first load sensor, a second load sensor, a displacement sensor, an inclination sensor and multiple soil pressure boxes and multiple strain gauges; the first load sensor is arranged on the vertical loading module, for collecting the vertical load data applied by the vertical loading module to the suction tube conductor frame model 400; the second load sensor is arranged on the horizontal loading module, for collecting the horizontal load data applied by the horizontal loading module to the suction tube conductor frame model 400; the displacement sensor is arranged on the horizontal loading module, for collecting the horizontal displacement data of the horizontal loading module; the inclination sensor is arranged at the upper end of the conductor frame body 401, for collecting the inclination data of the suction tube conductor frame model 400; the soil pressure box is arranged at the top cover and the wall of the suction tube foundation 403, for collecting the soil pressure data of the suction tube foundation 403; the strain gauge is arranged at the connection between the conductor frame body 401 and the suction tube foundation 403, for collecting the strain data at the connection between the conductor frame body 401 and the suction tube foundation 403.

[0089] Strain gauges are primarily used to measure strain at the connection between the suction tube foundation 403 and the jacket body 401, enabling analysis of load sharing among the three foundations when they are subjected to coordinated forces. Specifically, a pair of strain gauges are symmetrically positioned at the connection between each of the three suction tube foundations 403 and the jacket body 401, with the line connecting the two gauges oriented in the direction of horizontal load application. The strain gauges are arranged in a quarter-bridge configuration, with the bottom layer bonded with glue. They are tested to ensure they are functioning properly before use.

[0090] To measure the soil pressure on the suction cylinder foundation 403 as it pulls up and down during loading, soil pressure cells are placed on the top cover and wall of the suction cylinder foundation 403. The specific arrangement is shown in Figure 2. Two soil pressure cells are placed on the inside of the top cover of the front and rear cylinders to measure the soil pressure on the top cover; one soil pressure cell is placed on the outside of the front and rear cylinder skirts at different heights from the cylinder ends along the loading direction to measure the soil pressure on the outside of the cylinder skirts. Specifically, there are 16 soil pressure cells in total, four with a range of 100 kPa and 12 with a range of 50 kPa.

[0091] Specifically, the first load sensor and the second load sensor are tension and pressure sensors.

[0092] In this embodiment, the suction tube jacket prototype is scaled to form a suction tube jacket model 400, and then the model is tested to reflect the load-bearing performance of the prototype, thereby completing an effective test of the load-bearing performance of the suction tube jacket under load.

[0093] 3 , in some embodiments, the lower end of the jacket body 401 is welded to the top center of the suction tube foundation 403 via a rib 402 .

[0094] The lower end of the jacket body 401 is welded to the top center of the suction tube foundation 403 through a rib 402, forming a central connection structure between the jacket body 401 and the suction tube foundation 403. The suction tube jacket can be tested under this structure later.

[0095] 4 , in some embodiments, the lower end of the jacket body 401 is welded to the top edge of the suction tube foundation 403 via a rib 402 .

[0096] Among them, the lower end of the jacket body 401 and the top edge of the suction tube foundation 403 are welded together through ribs 402, forming an edge connection structure between the jacket body 401 and the suction tube foundation 403. The suction tube jacket can be tested under this structure later.

[0097] 5 , in some embodiments, a steel frame 300 is further included. The lower portion of the steel frame 300 is used to install the test soil trough 100 , and a crossbeam 301 is provided on the upper portion of the steel frame 300 . A horizontal guide rail 303 is provided on the crossbeam 301 , and a mounting connector 302 with an adjustable mounting position is provided on the horizontal guide rail 303 . The mounting connector 302 is fixedly connected to the multi-directional loading device 200 .

[0098] The steel frame 300 is divided into two parts. The lower steel frame 300 houses the test soil trough 100, while the upper steel frame 300 houses the loading device. This allows the entire testing apparatus to be placed within the steel frame 300, creating a safe testing environment. A horizontal guide rail 303 is mounted on the crossbeam 301. The mounting connector 302 on the horizontal guide rail 303 is adjustable. Adjusting the position of the mounting connector 302 as needed adjusts the position of the vertical and horizontal loading modules in the multi-directional loading device 200.

[0099] Specifically, the steel frame 300 has a length, width, and height of 1.40 m×0.86 m×3.00 m.

[0100] FIG6 is a test method for an offshore wind turbine suction tube jacket provided in an embodiment of the present application. Referring to FIG6 , in some embodiments, the test method for an offshore wind turbine suction tube jacket is applied to the test device for the offshore wind turbine suction tube jacket described above. The test method includes the following steps:

[0101] S601, placing the suction tube jacket model at a predetermined position in the test soil trough.

[0102] Before the test begins, the suction tube jacket model needs to be placed in a predetermined position to facilitate subsequent installation of the suction tube jacket model.

[0103] Preferably, before conducting the test, sand and soil for the test need to be prepared. The sand and soil preparation process includes:

[0104] Step 1: Prepare loose sandy soil using the sand-rain method and put the loose sandy soil into the test soil trough.

[0105] Step 2: After the sand and soil are prepared, level the sand and soil in the test soil trough.

[0106] S602: Apply vertical load to the suction tube jacket model using a vertical loading module of a multi-directional loading device, so as to install the three-tube foundation of the suction tube jacket model in the sand of the test soil trough.

[0107] During the test, the suction tube jacket model must first be installed in the sand at the predetermined location and depth, ensuring good contact between the model and the sand. Therefore, a vertical loading module is used to apply a vertical load to the suction tube jacket model, allowing the three-tube foundation of the suction tube jacket model to be installed in the sand of the test soil trough.

[0108] Before conducting the bearing capacity test of the suction cylinder foundation, the three-cylinder foundation needs to be installed using vertical static pressure. During the installation process, the penetration load and strain data are measured to analyze the structural characteristics of the suction cylinder foundation during the penetration process and the vertical bearing characteristics of the suction cylinder foundation.

[0109] Preferably, the specific installation process of the three-tube foundation includes:

[0110] Step 1: Use the vertical loading module to apply a vertical load to the top centroid of the suction tube jacket model to uniformly press the suction tube foundation of the three-tube foundation into the sand in the test soil trough.

[0111] The vertical loading module was aligned with the centroid of the suction tube jacket model's top and pressed downward at a constant speed of 1 mm / s, forcing the suction tube foundation of the model into the sand of the test trough. Real-time vertical load and joint strain data were recorded during the loading process. Applying pressure at the centroid ensured that the three foundations of the suction tube jacket model were installed vertically downward.

[0112] Step 2: During the process of applying the vertical load, when the vertical load data reaches the preset load, the vertical loading module stops applying the vertical load.

[0113] Among them, when the vertical load reaches the preset load, it is considered that there is good contact between the suction tube foundation of the suction tube jacket and the sand soil, indicating that the three-tube foundation is installed, and the installation process is stopped.

[0114] S603: Apply a horizontal load to the suction tube jacket model using a horizontal loading module of a multi-directional loading device to perform a horizontal ultimate bearing capacity test on the three-tube foundation of the suction tube jacket model.

[0115] Among them, after the test model is installed, the horizontal ultimate bearing capacity test of the suction tube jacket model is carried out to test the horizontal bearing performance of the suction tube jacket model.

[0116] Preferably, the testing process of the horizontal ultimate bearing capacity test includes:

[0117] Step 1: Use the horizontal loading module to apply a horizontal load to the loading point of the suction tube jacket model; wherein the loading point is used to ensure that when the three tube foundations of the suction tube jacket model are subjected to the horizontal load, only one of the three tube foundations is in a tension state.

[0118] After the test model was installed, the horizontal ultimate bearing capacity test of the three-tube foundation was conducted. First, the loading point's loading position, loading height, and loading direction were determined to ensure that when the three-tube foundation was loaded, only one suction tube was in tension. The horizontal loading module was aligned with the loading point. Loading was performed using the slow maintenance method at a loading speed of 1 mm / s. Real-time load, displacement, inclination, and strain data at the connection were recorded during the loading process. This yielded the Qs curve for the three-tube foundation under single-tube tension.

[0119] Step 2: During the process of applying the horizontal load, when the reaction force of the three-tube foundation reaches its peak value and remains stable, and the sand foundation reaches its ultimate bearing capacity and is completely destroyed, the horizontal loading module stops applying the horizontal load.

[0120] Among them, when the reaction force of the three-tube foundation of the suction tube jacket reaches its peak and remains stable, and the sand foundation reaches its ultimate bearing capacity and is completely destroyed, it indicates that the horizontal ultimate load of the three-tube foundation has been reached. At this time, the horizontal loading module stops applying the horizontal load and the test is completed.

[0121] S604, during the test process, the sensor assembly is used to collect test data; wherein the test data includes vertical load data, horizontal load data, horizontal displacement data, inclination data of the suction tube jacket model, soil pressure data of the suction tube foundation, and strain data at the connection between the jacket body and the suction tube foundation.

[0122] The test not only measured the macroscopic physical quantities of the three-tube foundation, but also the strain state of the suction tube foundation. Therefore, in addition to measuring the horizontal load and displacement at the loading point of the suction tube jacket model, the overall inclination change of the model during loading was also measured, along with the soil pressure data of the suction tube foundation and the strain data at the connection between the jacket body and the suction tube foundation.

[0123] In this embodiment, in order to make the model test results provide a reference for actual engineering design as much as possible, the test scale is selected according to the main issues involved in the test design, so as to achieve the purpose of making the test results reflect the prototype characteristics as much as possible. According to the test scale theory, in order for the model test to reflect the prototype as much as possible, some specific conditions in the test must be met to achieve motion similarity and constitutive relationship similarity. Dimensional analysis is the basis of the test scale theory. This application conducts a multi-dimensional analysis of the model test and uses the π theory to analyze the key dimensionless quantities in the test. Derive the similarity law that the model test needs to meet. If the geometric scale of the model test is 1:100, the following expression can be used:

[0124] Where λ and k represent the geometric scale of length and gravitational acceleration respectively, L P 、g P 、L M and g m represent the length and gravitational acceleration in the model and prototype respectively.

[0125] It can be seen that if the same volume of soil is used in the prototype and model tests, that is, its density d S are the same, then their effective weights g M The ratio is also equal to k=1.

[0126] After defining the independent geometric scales λ and k, the dimensionless parameter combination π is selected by studying the dimensional matrix of the relevant quantities of the physical problem involved. In the framework of small-scale experiments, it is generally also necessary to satisfy the similarity of forces:

[0127] Where F is the dimensionless force, r s is the effective bulk density of the soil, and L is the geometric length in the reference system. f If it does not change, then:

[0128] Then the similarity expression of force in the similarity criterion is as follows:

[0129] The conversion scales of other relevant physical quantities can also be obtained according to the above method, see Table 1 for details.

[0130] Table 1 Similarity criteria for small-scale model tests

[0131] Under small-scale model test conditions, the time scale is actually determined by the geometric scale of the model. Therefore, the acceleration in the model is not affected by the model size and is consistent with that in the prototype, as shown in the following formula:

[0132] therefore:

[0133] Among them, a p and x p It represents the acceleration and displacement in the prototype, a M and x M It represents the acceleration and displacement in the model test.

[0134] Based on the above test scale content, for the operability and repeatability of the test, this test was designed according to the geometric scale of 1:100.

[0135] This test method can be used to study the bearing pattern of the three-tube foundation of the suction tube jacket under horizontal load, the load sharing ratio of each suction tube foundation, and the source and generation mechanism of the foundation bearing capacity. It has a good reference value for the prototype of the suction tube jacket.

[0136] In addition, there are two ways to connect the suction tube foundation and the jacket body: edge connection and center connection. Under the condition of the same superstructure, the suction tube jacket models of the two structures are tested separately, and the influence of the change of the position of the connection point between the suction tube foundation and the jacket body on the anti-tilt stability of the suction tube jacket can also be studied.

[0137] Preferably, after the test is completed, the suction tube jacket model can be dismantled, and the sand and soil within the influence range of the suction tube jacket model can be shoveled out, backfilled to the initial elevation and leveled to carry out the next set of tests.

[0138] Preferably, after the test is completed, the reliability of the test data can be verified by finite element simulation. The specific process is as follows:

[0139] Step 1: Construct a finite element model of the suction tube jacket model.

[0140] Among them, based on the model test size, ABAQUS was used to establish the finite element model of the central connection and eccentric connection suction tube jacket model.

[0141] Step 2: Perform finite element simulation test on the finite element model to obtain finite element test results of the finite element model.

[0142] Step 3: Compare the finite element test results with the test data to verify the reliability of the test data.

[0143] The primary purpose of comparing test data with finite element test results is to verify the accuracy and reliability of the test data and to evaluate the predictive capabilities and precision of the finite element model. This comparison can reveal discrepancies and analyze the causes of these discrepancies, providing guidance for subsequent structural design, optimization, and testing.

[0144] Below, a specific test result will be used to further illustrate a test method for an offshore wind power suction tube jacket of the present application.

[0145] Among them, the prototype of the suction tube jacket tested is 40m high, the tube is 20m high and the diameter is 20m.

[0146] Among them, the geometric scale of the suction tube jacket model and the suction tube jacket prototype is 1:100. The suction tube jacket model used in the test is 400 mm high, with a tube diameter of 200 mm and a height of 200 mm. The suction tube jacket model is made of stainless steel with an elastic modulus of 210 GPa, and the tube diameter × wall thickness are both 100 mm × 2 mm.

[0147] The test trough, consisting of a trough body and sand, simulates the installation environment of a suction tube jacket. Specifically, the test sand used was Fujian standard sand. The cumulative particle size distribution curve is shown in Figure 7. Its uniformity coefficient Cu is 4.04, and its curvature coefficient Cc is 1.06, indicating poorly graded fine sand. Specific soil property parameters for the test sand are shown in Table 2.

[0148] Table 2 Test parameters of sandy soil properties

[0149] Specifically, the test soil trough has a size of 1.5 m × 1.5 m × 1.5 m.

[0150] 1. Analysis of the three-tube foundation penetration process.

[0151] Before conducting the bearing capacity test of the suction tube foundation, the three-tube foundation needs to be installed using vertical static pressure. During the installation process, the penetration load and strain data are measured to analyze the structural characteristics of the suction tube foundation during the penetration process and the vertical bearing characteristics of the three-tube foundation.

[0152] (1) Study on the penetration process of eccentrically connected three-tube foundation.

[0153] A total of four tests were conducted on the installation process of the eccentrically connected three-tube foundation, and the penetration load and vertical displacement curves are shown in Figure 8.

[0154] As shown in Figure 8, the Qs curves for the three-tube foundation during installation have a high degree of overlap, demonstrating good test repeatability. Initially, the vertical load increases linearly with vertical displacement. At approximately 140 mm of penetration, the Qs curve shows a distinct inflection point, with a steep increase in slope. This indicates that contact has begun between the suction tube foundation cap and the soil, forming a stable cap load pattern. To prevent virtual contact, penetration of the three-tube foundation was continued until a force of 6.5 kN was reached, at which point the load was stopped. The contact between the foundation and the soil was deemed sufficiently stable for horizontal bearing capacity testing.

[0155] (2) Study on the penetration process of the central connection three-tube foundation

[0156] Two tests were conducted on the installation process of the centrally connected three-tube foundation. The penetration load and vertical displacement curves in the two sets of tests are shown in Figure 8.

[0157] As shown in Figure 8, the Qs curves for the installation of the centrally connected and eccentrically connected three-tube foundations are quite similar. In both cases, the penetration force increases slowly and linearly with the increase in penetration displacement during the initial penetration. When the penetration displacement reaches approximately 140 mm, the Qs curve shows a clear peak, and the penetration force increases rapidly. This indicates that contact between the tube cap and the soil has begun at this point. Similarly, to prevent virtual contact, the foundation is penetrated until the penetration load reaches approximately 6.5 kN, at which point the contact between the tube and the soil is considered stable, and the horizontal bearing capacity test of the foundation can be performed. Comparing the Qs curves during the penetration of the two foundations yields the results shown in Figure 8.

[0158] As can be seen from Figure 8, the variation pattern of the penetration force of the three-tube foundation during installation does not change with the change of the foundation form. There is no obvious difference in the initial slope, inflection point position, and slope of the curve after the inflection point of the two foundation penetration forces changing with displacement.

[0159] 2. Analysis of horizontal bearing capacity of three-tube foundation.

[0160] After the three-tube foundation is installed, the horizontal bearing capacity of the foundation is studied. During the test, horizontal load data, horizontal displacement data, inclination data and strain data are recorded. The bearing capacity, failure mode and movement characteristics of the foundation when subjected to horizontal loads can be studied and analyzed.

[0161] Under the action of horizontal loads, the soil in front of the three suction tube foundations showed significant bulging, while the soil behind them showed depression. The suction tube jacket model overturned as a whole after the horizontal load was applied. The two compression tubes experienced a small downward displacement with some rotation, while the single tension tube experienced a large upward displacement with some rotation. The jacket structure showed no significant deformation during or after loading, indicating that it was in the elastic phase during loading.

[0162] (1) Study on the horizontal bearing characteristics of eccentrically connected three-tube foundation.

[0163] A total of four tests were conducted on the horizontal bearing characteristics of the eccentrically connected three-tube foundation, and the horizontal load-horizontal displacement and inclination angle-horizontal displacement curves are shown in Figure 9.

[0164] Figure 9 shows that the load-displacement curves obtained from the four tests exhibit good repeatability. The curves all reach a peak when the horizontal displacement reaches approximately 10 mm. Afterward, the curves gradually flatten out and exhibit a slight weakening. Taking the peak value of the curve as the ultimate bearing capacity of the foundation, the bearing capacities for the four tests are 281.60 N, 279.32 N, 252.11 N, and 271.29 N, respectively. The errors are within the control range, and the test conclusions can be considered reliable. Furthermore, it was found that the foundation's inclination angle increases linearly with increasing horizontal displacement. When the horizontal displacement reaches 45 mm, the foundation's inclination angle reaches approximately 3.0° to 3.5°. This indicates that the vertical position of the foundation's rotation center is 730 to 830 mm below the load application point, that is, 200 to 300 mm below the soil surface, near the bottom of the suction tube foundation.

[0165] (2) Study on the horizontal bearing characteristics of the centrally connected three-tube foundation.

[0166] Four tests were also conducted on the horizontal bearing characteristics of the centrally connected three-tube foundation, and the horizontal load-horizontal displacement and inclination-horizontal displacement curves are shown in Figure 10.

[0167] As shown in Figure 10, the four horizontal bearing capacity tests of the centrally connected three-tube foundation also exhibit good repeatability. However, its load-displacement curve differs somewhat from that of the eccentrically connected three-tube foundation. When the horizontal displacement reaches approximately 3 mm, the curve shows a clear inflection point, after which the horizontal load slowly increases with displacement. The horizontal load reaches a peak at approximately 35 mm, after which it begins to slowly decrease. Using the peak value of the curve as the ultimate bearing capacity of the foundation, the bearing capacities of the four tests are 235.96 N, 235.56 N, 230.58 N, and 228.42 N, respectively. The test conclusions can be considered to have a certain degree of credibility. The change pattern of the inclination angle of the central connection foundation is consistent with that of the eccentric connection foundation. With the increase of horizontal displacement, the inclination angle of the foundation increases linearly. When the horizontal displacement reaches 70mm, the inclination angle of the foundation reaches about 5.5°~6.5°. It can be obtained that the vertical position of the rotation center of the foundation is 620mm~720mm below the load loading point, that is, 90mm~190mm below the soil surface, indicating that the rotation center of the central connection three-tube foundation is slightly higher than the rotation center of the eccentric connection three-tube foundation.

[0168] 3. Data analysis.

[0169] Figures 11 and 12 show displacement vector diagrams for the centrally and eccentrically connected suction tube jacket models after horizontal loading. For both foundations, the displacement pattern of the compression tube is primarily rotational about a point in the lower left corner of the tube, while the displacement pattern of the pull-out tube is primarily pull-out with some rotation. For the eccentric connection, due to the increased tube spacing, both the rotational displacement of the compression tube and the pull-out displacement of the tension tube are greater than for the centrally connected case.

[0170] Figures 13 and 14 show the resultant forces and moments acting on the lower compression tube (compression tube) and upper tension tube (tension tube) in a three-tube foundation. As can be seen from the figures, there is no significant difference in the pressure and force on the compression and tension tubes for both central and eccentric connections. For a three-tube foundation with a mud surface subjected to both horizontal forces and bending moments, both the tension and compression tubes generate a bending moment in the same direction as the load, with the bending moment generated in the eccentric connection case being greater than that in the central connection case.

[0171] Figure 15 shows the lateral earth pressure generated by the lower pressure tube and the upper pull tube in the three-tube foundation. As can be seen from the figure, the lateral earth pressure distribution of the lower pressure tube and the upper pull tube both show the characteristics of rotation. Due to the rotation of the lower pressure tube, a large passive earth pressure is generated at the tube wall.

[0172] Figure 16 shows the equivalent plastic strain (PEEQ) of different cylinders. It can be seen that the downward cylinder generates a larger plastic strain due to rotation. The plastic strain of the eccentric connection is greater than that of the central connection. Therefore, in actual design, it is necessary to pay attention to checking the anti-overturning bearing capacity of the downward cylinder.

[0173] The above analysis shows that converting the bending moment load of the three-tube foundation into an upward pullout load for the upper pull-tube foundation and a downward compressive load for the lower compressive bucket foundation without considering the bending moment provided by the bucket foundation is a simplistic approach. Subsequent tests will further investigate the stress response of a single tube under moment load and the moment sharing ratio.

[0174] 4. Finite element analysis.

[0175] Based on the model test size, the finite element model of the central connection and eccentric connection suction tube jacket model was established using ABAQUS.

[0176] The loading process consists of three steps: first, balancing the soil's in-situ stresses to eliminate deformation due to its own weight; then, applying the self-weight stresses of the jacket structure and suction tube foundation; and finally, applying a displacement load at a reference point 53 cm from the mud surface. Figures 17 and 18 show the displacement and vertical stress nephograms after in-situ stress balancing. They show that the displacement under the soil's own weight is 10-7 m, demonstrating that in-situ stress balancing meets the requirements.

[0177] Figures 19 and 20 show the displacement-inclination curve comparison results of the eccentrically connected and centrally connected three-tube foundations. The two are basically the same, indicating that the overall motion pattern of the finite element simulation of the suction tube jacket model is consistent with the facts.

[0178] Figures 21 and 22 show the displacement-force curves at the loading point for the model test and finite element simulation results. The trends and values ​​are essentially the same, indicating that the finite element method can simulate the forces acting on the suction tube jacket model under horizontal loads.

[0179] Figure 23 shows the plastic strain of the jacket structure. After loading, the jacket structure exhibits no plastic strain, but rather elastic deformation, consistent with experimental observations. This comparison demonstrates the feasibility of using finite element methods to simulate the horizontal load-bearing characteristics of the suction tube jacket model foundation.

[0180] In the above embodiments, the description of each embodiment has its own emphasis. For parts not described in detail in a particular embodiment, please refer to the relevant description of other embodiments. The technical features of the above embodiments can be combined in any way. To keep the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0181] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered merely as exemplary, and the true scope and spirit of the present application are indicated by the appended claims.

[0182] It should be understood that the present application is not limited to the exact structure described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A test device for an offshore wind power suction tube conductor rack, characterized in that: It includes a suction tube pipe frame model, a test soil trough, a multi-directional loading device and a sensor assembly, wherein the suction tube pipe frame model is made by scaling the suction tube pipe frame prototype; The suction tube catheter rack model includes a catheter rack body and a three-tube foundation, wherein the three-tube foundation includes three suction tube foundations distributed in a triangle, the lower end of the suction tube foundation is open and the top end is fixedly connected to the lower end of the catheter rack; The test soil trough comprises a trough body, wherein the trough body is filled with sand, and the sand is used to install the three-tube foundation of the suction tube conductor rack model; The multi-directional loading device is arranged above the test soil trough, and the multi-directional loading device comprises a vertical loading module and a horizontal loading module, and the vertical loading module and the horizontal loading module are used to apply a vertical load and a horizontal load to the suction tube jacket model installed in the test soil trough respectively; The sensor assembly is used to collect test data; wherein the test data includes vertical load data, horizontal load data, horizontal displacement data, inclination data of the suction tube conductor rack model, soil pressure data of the suction tube foundation, and strain data at the connection between the conductor rack body and the suction tube foundation.

2. A test device for an offshore wind power suction tube conductor frame according to claim 1, characterized in that: The lower end of the catheter frame body is welded to the top center of the suction tube foundation through ribs.

3. A test device for an offshore wind power suction tube conductor frame according to claim 1, characterized in that: The lower end of the catheter frame body is connected to the top edge of the suction tube foundation by welding through ribs.

4. A test device for an offshore wind power suction tube conductor frame according to any one of claims 1 to 3, characterized in that: The sensor assembly includes a first load sensor, a second load sensor, a displacement sensor, an inclination sensor, a plurality of earth pressure boxes, and a plurality of strain gauges; The first load sensor is arranged on the vertical loading module, and is used to collect vertical load data applied by the vertical loading module to the suction tube jacket model; The second load sensor is arranged on the horizontal loading module, and is used to collect horizontal load data applied by the horizontal loading module to the suction tube jacket model; The displacement sensor is arranged on the horizontal loading module, and is used to collect horizontal displacement data of the horizontal loading module; The inclination sensor is arranged at the upper end of the catheter frame body, and is used to collect the inclination data of the suction tube catheter frame model; The soil pressure box is arranged at the top cover and the wall of the suction cylinder foundation, and is used to collect soil pressure data of the suction cylinder foundation; The strain gauge is arranged at the connection between the conductor frame body and the suction cylinder foundation, and is used to collect strain data at the connection between the conductor frame body and the suction cylinder foundation.

5. A testing device for an offshore wind power suction tube conductor frame according to any one of claims 1 to 3, characterized in that: It also includes a steel frame, the lower part of which is used to install the test soil trough, and the upper part of which is provided with a crossbeam; A horizontal guide rail is arranged on the crossbeam, and a mounting connector with an adjustable mounting position is arranged on the horizontal guide rail. The mounting connector is fixedly connected to the multi-directional loading device.

6. A testing device for an offshore wind power suction tube conductor frame according to any one of claims 1 to 3, characterized in that the vertical loading module includes a vertical loading hydraulic cylinder, a vertical loading pneumatic cylinder or a vertical loading screw, and the horizontal loading module includes a horizontal loading hydraulic cylinder, a horizontal loading pneumatic cylinder or a horizontal loading screw.

7. A test method for an offshore wind power suction tube conductor frame, characterized in that: Based on the testing device for an offshore wind power suction tube conductor frame according to any one of claims 1 to 6, the method comprises: Placing the suction tube pipe frame model at a predetermined position of the test soil trough; Applying a vertical load to the suction tube jacket model using a vertical loading module of a multi-directional loading device, so as to install the three-tube foundation of the suction tube jacket model in the sand of the test soil trough; Applying a horizontal load to the suction tube jacket model using a horizontal loading module of a multi-directional loading device to perform a horizontal ultimate bearing capacity test on the three-tube foundation of the suction tube jacket model; During the test, the sensor assembly is used to collect test data; wherein the test data includes vertical load data, horizontal load data, horizontal displacement data, inclination data of the suction tube conductor rack model, soil pressure data of the suction tube foundation, and strain data at the connection between the conductor rack body and the suction tube foundation.

8. A test method for an offshore wind power suction tube jacket according to claim 7, characterized in that: Applying a vertical load to the suction tube jacket model using a vertical loading module of a multi-directional loading device to install the three-tube foundation of the suction tube jacket model in the sand of the test soil trough includes: Using the vertical loading module to apply a vertical load to the top centroid position of the suction tube jacket model, so as to uniformly press the suction tube foundation of the three-tube foundation into the sand in the test soil trough; During the process of applying the vertical load, when the vertical load data reaches a preset load, the vertical loading module stops applying the vertical load.

9. A test method for an offshore wind power suction tube jacket according to claim 7, characterized in that: Applying a horizontal load to the suction tube jacket model by using a horizontal loading module of a multi-directional loading device to perform a horizontal ultimate bearing capacity test on the three-tube foundation of the suction tube jacket model, including: The horizontal loading module is used to apply a horizontal load to the loading point of the suction tube jacket model; wherein the loading point is used to ensure that when the three-tube foundation of the suction tube jacket model is subjected to a horizontal load, only one suction tube foundation of the three-tube foundation is in a tension state; In the process of applying the horizontal load, when the reaction force of the three-tube foundation reaches a peak value and remains stable, and the sand foundation reaches the ultimate bearing capacity and is completely destroyed, the horizontal loading module stops applying the horizontal load.

10. A method for testing an offshore wind power suction tube jacket according to any one of claims 7 to 9, characterized in that: The method further comprises: Constructing a finite element model of the suction tube catheter rack model; Performing a finite element simulation test on the finite element model to obtain a finite element test result of the finite element model; The finite element test result is compared with the test data to verify the reliability of the test data.

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