A composite screw anchor installation and loading test bench

Abstract

The application discloses a composite spiral anchor installation and loading test platform, and relates to anchor technology in ocean engineering. The platform comprises a support frame, a rotating drive mechanism, a first linear motion mechanism and a second linear motion mechanism, and a control system. The rotating drive mechanism is arranged on the support frame and used for driving the spiral anchor to rotate. The first linear motion mechanism is drivingly connected to the rotating drive mechanism and used for driving the rotating drive mechanism to move in a first direction. The second linear motion mechanism is drivingly connected to the rotating drive mechanism and used for driving the rotating drive mechanism to move in a second direction orthogonal to the first direction. The control system is electrically connected to the rotating drive mechanism, the first linear motion mechanism and the second linear motion mechanism. The application has the characteristics of high rigidity, modularity and full-process automation, integrates mechanical transmission, servo control and multi-dimensional data acquisition, is suitable for simulating the installation and bearing process of the spiral anchor in a real seabed or land soil environment, and is used for researching the mechanical properties of the spiral anchor in a full life cycle under complex loads.

Description

Technical Field

[0001] This invention relates to marine engineering anchoring technology, and more specifically, to a composite helical anchor installation and loading test bench. Background Technology

[0002] In marine and civil engineering, helical anchors, as a highly efficient foundation type, require torque and downward pressure for installation to achieve downward penetration. Their load-bearing capacity is affected by soil disturbance during installation and the complex load environment during service. Especially in marine environments, the foundation structure is constantly subjected to long-term continuous loads from wind, waves, and currents transmitted from the superstructure. The stress mode is often a multi-dimensional coupling of vertical uplift, horizontal shear, and bending moments.

[0003] However, existing indoor model testing devices still have certain limitations when conducting related research:

[0004] (1) Insufficient functional integration and control precision: Existing test equipment often separates "installation" and "loading", or can only perform static loading in a single dimension (such as vertical pull-out or horizontal thrust alone). Although some devices have basic composite action capabilities, the control precision in multi-axis linkage is often insufficient to meet the requirements of refined experiments. They cannot accurately reproduce the actual working condition of the helical anchor bearing complex multi-directional loads immediately after installation, nor can they accurately simulate the influence of tilt pull-out or dynamic cyclic vector force on the anchor body.

[0005] (2) The installation process control is relatively crude: The installation of the spiral anchor requires precise coordination of torque and downward pressure. Most existing devices lack real-time linkage control of these two parameters, making it difficult to maintain a constant installation advance ratio when the soil resistance changes. This makes it impossible to quantitatively analyze the specific impact of different installation processes on the stress state of the soil around the anchor and the long-term performance effect.

[0006] Therefore, developing a high-rigidity, integrated experimental device capable of precise simulation and monitoring of the entire process of helical anchor installation and stress is of great significance for in-depth research on the mechanical mechanism of helical anchors in complex environments and for further promoting the practical application of helical anchors in marine engineering. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a composite helical anchor installation and loading test bench that addresses the shortcomings of the existing technology. It features high rigidity, modularity, and full-process automation, integrating mechanical transmission, servo control, and multi-dimensional data acquisition. It is suitable for simulating the installation and bearing process of helical anchors in real seabed or terrestrial soil environments, and for studying the mechanical performance of helical anchors throughout their entire life cycle under complex loads.

[0008] The composite spiral anchor installation and loading test bench of the present invention includes:

[0009] A supporting frame, in which simulation components are installed;

[0010] A rotary drive mechanism, which is mounted on the support frame, is used to drive the helical anchor to rotate;

[0011] A first linear motion mechanism is driven by the rotary drive mechanism and is used to drive the rotary drive mechanism to move along a first direction.

[0012] The second linear motion mechanism is driven by the rotary drive mechanism and is used to drive the rotary drive mechanism to move along a second direction orthogonal to the first direction.

[0013] The control system is electrically connected to the rotary drive mechanism, the first linear motion mechanism, and the second linear motion mechanism.

[0014] The control system is configured as follows:

[0015] In the first working mode, the rotational motion of the rotary drive mechanism and the linear motion of the second linear motion mechanism are controlled in a coordinated manner based on a dynamic electronic gear coupling algorithm, so that the spiral anchor penetrates the simulation component at a predetermined advance ratio;

[0016] In the second working mode, the set target load vector is decomposed into a first component along the first direction and a second component along the second direction. Then, the linear / circular interpolation algorithm is called to instruct the first linear motion mechanism and the second linear motion mechanism to perform mixed control of force and displacement.

[0017] Preferably, the dynamic electronic gear coupling algorithm is as follows:

[0018] An electronic gear connection is established between the loading shaft of the rotary drive mechanism and the loading shaft of the second linear motion mechanism;

[0019] Based on the topological characteristics of the spiral anchor, kinematic constraint equations are established to solve for the linear loading velocity and phase linear displacement of the loading axis of the second linear motion mechanism.

[0020] The real-time phase linear displacement is calculated based on the electronic gear coefficient and the real-time angular displacement of the helical anchor.

[0021] The difference between the calculated phase linear displacement and the real-time phase linear displacement is used to determine whether the loading axis of the second linear motion mechanism has a displacement deviation; if a displacement deviation occurs, the interpolation of the servo system of the second linear motion mechanism is used to ensure that the position deviation is within the allowable deviation range.

[0022] Preferably, if the current simulated wave cyclic load condition is as follows, an objective function is defined:

[0023] ,

[0024] Real-time force control is calculated using the following formula:

[0025] ,

[0026] The real-time force control is used as the target load vector;

[0027] in, For average static load, Here, f is the cyclic amplitude, f is the loading frequency, and t is the current time. α is the phase angle of the composite force; α is the incident angle of the force.

[0028] Preferably, it further includes an array-type force sensing component; the array-type force sensing component includes four tension and compression sensors, which are evenly distributed along the circumferential direction on the force transmission path between the rotary drive mechanism and the helical anchor, and the control system is configured to calculate the eccentric bending moment of the helical anchor based on the sensing values ​​collected by the four tension and compression sensors.

[0029] Preferably, the formula for calculating the eccentric bending moment is:

[0030] ,

[0031] in, To obtain the eccentric bending moment, R is the lever arm constant. These are the sensing values ​​collected by four tension and compression sensors.

[0032] Preferably, a torque sensor is mounted on the loading shaft of the rotary drive mechanism;

[0033] The control system is configured to: convert the torque value M measured by the torque sensor into a bending moment component. and bending moment components And according to the bending moment components and bending moment components Set the eccentricity safety threshold:

[0034] ;

[0035] When the calculated eccentric bending moment is greater than the eccentric safety threshold, the system is determined to be in an asymmetric instability risk state, and a servo lock-up command is generated.

[0036] Preferably, it further includes a deformation compensation connector, which is disposed between the mounting base of the helical anchor and the fixing base of the tension and compression sensor.

[0037] Preferably, the deformation compensation connector is a one-piece elastomer.

[0038] Preferably, the first linear motion mechanism includes two horizontal linear loading modules mounted in parallel on the support frame.

[0039] Preferably, the second linear motion mechanism includes a mounting bracket, on which the sliders of the two horizontal linear loading modules are jointly fixed. A horizontal guide optical axis is also provided on the support frame on both sides of the horizontal linear loading module, and the mounting bracket is slidably connected to the horizontal guide optical axis. Two symmetrically arranged vertical linear loading modules are mounted in the mounting bracket, and a rotary drive mechanism is jointly fixed on the sliders of the two vertical linear loading modules. Vertical guide optical axes are also fixed at the four corners of the mounting bracket, and the rotary drive mechanism is slidably connected to the vertical guide optical axis.

[0040] Beneficial effects

[0041] The advantages of this invention are:

[0042] 1. This invention constructs a planar motion execution system based on an orthogonal coordinate system, with synchronous drive of dual linear motion mechanisms. A reinforced horizontal guide optical axis is also configured to resist overturning moments, achieving precise control of horizontal and vertical displacements and ensuring the trajectory geometric stability of the test platform under complex vector loading. Two operating modes are designed, and a dynamic electronic gear coupling algorithm solves the technical problem of traditional displacement control's inability to guarantee a constant thrust ratio. Multi-axis linkage is used to accurately simulate the nonlinear mechanical boundaries under complex marine environmental loads, including tilting pull-out, cyclic lateral thrust, and wind-wave-current coupling.

[0043] 2. To address the non-axisymmetric stress characteristics of the helical anchor, an array-type eccentric monitoring system was constructed between the rotary drive mechanism and the helical anchor, forming an array-type sensing plane. This allows the system to output a total axial force with a high signal-to-noise ratio and to calculate the eccentric bending moment of the helical anchor in real time during the loading process. This provides multi-dimensional data support for ensuring equipment safety and analyzing anchor-soil interactions in heterogeneous soils, ensuring the safety of the test bench operation and preventing damage to the equipment structure.

[0044] 3. The support frame features an open working space at its bottom and integrates detachable I-beams. This control allows the soil simulation bucket or water tank to be pushed in / out of the test area as a whole, enabling rapid switching and simulation of hard soil on land, soft seabed, and underwater geological environments. Furthermore, the closed-loop locked support frame provides a stable physical boundary for the system, effectively absorbing structural vibrations during operation under loads of thousands of Newtons. Attached Figure Description

[0045] Figure 1 This is a first-view schematic diagram of the three-dimensional structure of the test platform of the present invention.

[0046] Figure 2 This is a second-view schematic diagram of the three-dimensional structure of the test platform of the present invention.

[0047] Figure 3 This is a schematic diagram of the rotary drive mechanism and the spiral anchor installation structure of the present invention.

[0048] Figure 4 This is a schematic diagram of the test bench workflow of the present invention.

[0049] The components include: 1. Rotary drive mechanism; 2. First linear motion mechanism; 3. Second linear motion mechanism; 4. Vertical guide optical axis; 5. Horizontal guide optical axis; 6. Support frame; 7. Simulation component; 8. Detachable I-beam; 9. Disc geared motor; 10. Torque sensor; 11. Tension and compression sensor; 12. Clamping head; 13. Spiral anchor; 14. Fixed base; 15. Deformation compensation connector; 16. Mounting base; 17. Mounting bracket. Detailed Implementation

[0050] The present invention will be further described below with reference to embodiments, but this does not constitute any limitation on the present invention. Any limited modifications made by any person within the scope of the claims of the present invention are still within the scope of the claims of the present invention.

[0051] See Figures 1-3 The present invention provides a composite spiral anchor installation and loading test bench, which mainly includes a support frame 6, a rotary drive mechanism 1, and a first linear motion mechanism 2, which are driven by the rotary drive mechanism 1, the second linear motion mechanism 3, and the control system.

[0052] like Figure 1 As shown, the physical foundation of this test bench is a support frame 6 welded from I-beams, which is a high-rigidity portal frame. The bottom of the support frame 6 is designed with an open access opening, within which a detachable I-beam is installed, allowing for assembly and disassembly using bolts. When the detachable I-beam is removed, an open space is created at the bottom of the support frame 6, allowing simulation components 7 with a diameter of up to 1 meter, such as soil simulation buckets or large water tanks, to be pushed into the support frame 6 without obstruction. Once the simulation component 7 is in place, the detachable I-beam is reinstalled and locked, thus forming a closed-loop structure for the support frame 6.

[0053] The first linear motion mechanism 2 is driven and connected to the rotary drive mechanism 1, and is used to drive the rotary drive mechanism 1 to move along the first direction. Specifically, the first linear motion mechanism 2 includes two horizontal linear loading modules mounted in parallel on the support frame 6, constituting the X-axis loading execution unit of this test bench. The mounting bracket 17 of the first linear motion mechanism 2 is fixed together on the sliders of the two horizontal linear loading modules. In view of the problem that the vertical tower structure of this test bench has a high center of gravity and is prone to overturning moment during dynamic vector loading, two additional horizontal guide optical axes 5 are configured on both sides of the horizontal linear loading modules to share the vertical load and to widen the mounting bracket 17 to resist lateral moment. The X-axis loading execution unit of this embodiment can provide a thrust of 0-1000N and an effective stroke of 0-1000mm, and with the same level of control accuracy as the vertical linear loading module, such as ±0.1mm, it provides a horizontal component for planar vector composite loading.

[0054] The second linear motion mechanism 3 is connected to the rotary drive mechanism 1 and is used to drive the rotary drive mechanism 1 to move along a second direction orthogonal to the first direction. Specifically, the second linear motion mechanism 3, as a statically indeterminate vertical drive and guide mechanism on the Z-axis, mainly consists of two symmetrically arranged vertical linear loading modules mounted on the mounting bracket 17. The two ends of the rotary drive mechanism 1 are respectively fixed to the sliders of the two vertical linear loading modules. The vertical linear loading modules adopt a structure where a high-torque servo motor directly drives a precision ball screw. One vertical linear loading module can output 1500N of thrust, and when driven synchronously on both sides, it can provide 3000N of vertical push / pull force, meeting the power requirements for deep or hard soil penetration and large spiral anchor pull-out resistance. Furthermore, vertical guide shafts are evenly distributed at the four corners of the mounting bracket 17. These four vertical guide shafts, together with the two screws in the middle, form a six-point supported statically indeterminate structure, preventing radial vibration generated by the rotary drive mechanism 1 when outputting high torque. The mechanism has a long stroke of 0-1000mm, a position control accuracy of ±0.1mm, a force control accuracy of ±1N, and a speed control accuracy of ±0.1mm / s.

[0055] like Figure 3 As shown, the rotary drive mechanism 1 is mounted on the support frame 6 and is used to drive the helical anchor 13. Specifically, it is located at the center of the second linear motion mechanism 3, integrating the power unit, sensing unit, and quick-change interface unit. The power source of the rotary drive mechanism 1 is a disc-type geared motor 9. The output shaft of this motor serves as the loading shaft of the rotary drive mechanism 1 and is directly connected to a high-precision torque sensor 10, with a maximum output torque of ±500. The rotational speed control accuracy is ±0.1 rpm. The mounting base 16 of the spiral anchor is rigidly connected to the slider of the vertical linear loading module, and its lower part is connected to the fixing base 14 of the tension and compression sensor through the deformation compensation connector 15. The deformation compensation connector 15 is a one-piece elastic body. While transmitting axial force, it absorbs the high-frequency vibration of the motor and the installation coaxiality error by using a small amount of elastic deformation, preventing "stress" on the downstream sensor.

[0056] Four high-precision tension and compression sensors 11 are evenly embedded in the circumference between the mounting base 16 and the fixed base 14 to monitor the total axial force and eccentric bending moment. A standardized clamping head 12 is integrated at the bottom of the fixed base 14. The top of the helical anchor 13 has a standard threaded interface that can be quickly screwed into and locked with the clamping head 12. This design ensures coaxiality and rigidity of torque transmission, and eliminates the need to disassemble the sensor assembly when changing helical anchor samples with different blade types, effectively improving the efficiency of multi-condition comparative testing.

[0057] The control system is electrically connected to the rotary drive mechanism 1, the first linear motion mechanism 2, and the second linear motion mechanism 3, and is used to control these mechanisms. The specific control process of each hardware mechanism of the test bench will be described below.

[0058] This test bench is built based on " The distributed real-time control topology of "logic master station + high-performance motion control card" is adopted. Industrial buses enable microsecond-level synchronous communication between underlying execution units. For example... Figure 4 As shown, the core control logic of the control system is divided into four stages based on timing, and the determinism of mechanical actions and the authenticity of measurement data are ensured through a multi-level closed-loop algorithm.

[0059] The first phase is the system initialization phase, which mainly includes environment mapping and coordinate system initialization.

[0060] Remove the detachable I-beam, push the prefabricated soil simulation bucket directly under the test platform, then reinstall and lock the detachable I-beam. According to experimental requirements, use the horizontal linear loading module to move the rotary drive mechanism 1 to the specified test hole coordinates. Specifically, to eliminate the influence of mechanical assembly tolerances and sensor zero drift on accuracy, the system first executes a self-test program after power-on to determine that the servo drive motor is in initial state and the sensor output is at zero; then, it executes a kinematic calibration program to set a global orthogonal coordinate system: through the absolute position feedback and limit calibration of the servo encoder, a global Cartesian coordinate system (O-) with the geometric center of the soil simulation bucket as the origin is established. This stage establishes the spatial reference for subsequent vector loading, ensuring that the geometric angle error during force vector synthesis converges within the design tolerance (±0.5°). Next, an experimental mode is selected, and the working mode is determined based on this mode.

[0061] In this embodiment, the control system is configured with two operating modes: a first operating mode and a second operating mode. The purpose of the first operating mode is to install and penetrate the helical anchor, and the purpose of the second operating mode is to load the planar vector.

[0062] In the first working mode, the rotational motion of the rotary drive mechanism 1 and the linear motion of the second linear motion mechanism 3 are controlled in a coordinated manner based on the dynamic electronic gear coupling algorithm, so that the spiral anchor 13 penetrates the simulation part 7 at a predetermined advance ratio.

[0063] To address the technical challenge of traditional displacement control in maintaining a constant propulsion ratio, this working mode introduces a dynamic electronic gear coupling algorithm, specifically:

[0064] An electronic gear connection is established between the loading axis of the rotary drive mechanism 1 and the loading axis of the second linear motion mechanism 3. First, kinematic modeling is used to establish kinematic constraint equations based on the topological features of the helical anchor: the loading axis of the rotary drive mechanism 1 is set as the master axis, and the reference variables of the master axis include the real-time angular displacement of the master axis at time t. And the real-time angular velocity of the spindle at time t is The lead screw of the vertical linear loading module is used as the loading axis and is set as the driven axis. The reference variable of the driven axis is the linear velocity. Then, the linear loading velocity and phase linear displacement of the driven shaft are calculated in real time using a coupled solution. Specifically, based on the pitch P of the helical anchor, the system calculates the vertical linear loading velocity of the driven shaft in real time. Among them, linear loading speed The following rigid coupling relationship must be satisfied:

[0065] .

[0066] Phase linear displacement for:

[0067] .

[0068] Next, the real-time phase linear displacement is calculated based on the electronic gear coefficient and the real-time angular displacement of the helical anchor:

[0069] .

[0070] In the formula, This is the electronic gear ratio coefficient.

[0071] The difference between the calculated linear phase displacement and the real-time linear phase displacement is used to determine whether there is a displacement deviation in the loading axis of the second linear motion mechanism 3. If a displacement deviation occurs, the interpolation of the servo system of the second linear motion mechanism 3 is used to ensure that the position deviation is within the allowable range. That is, the actual displacement deviation at any time is ensured through microsecond-level interpolation of the servo system. This allows the spiral anchor to penetrate the soil according to the input propulsion ratio.

[0072] In the second working mode, the set target load vector is decomposed into a first component (i.e., horizontal component) along the first direction and a second component (i.e., vertical component) along the second direction. Then, the linear / circular interpolation algorithm is called to instruct the first linear motion mechanism 2 and the second linear motion mechanism 3 to perform mixed control of force and displacement.

[0073] Specifically, after the system enters the in-situ loading mode, it simulates complex marine environmental loads through multi-axis linkage based on the principle of vector space reconstruction. In the second working mode, firstly, through vector orthogonal decomposition, the computing unit maps the set target load vector to the orthogonal coordinate system in real time, decomposing it into horizontal components. With vertical components α is the angle of incidence of the force. Then, the linear / circular interpolation algorithm in the motion control card is invoked to instruct the horizontal linear loading module (X-axis) and the vertical linear loading module (Z-axis) to perform hybrid control of force and displacement. The real-time force control of the loading axes of the horizontal and vertical linear loading modules is expressed as follows:

[0074] .

[0075] For the simulated wave cyclic load condition, the objective function is set as follows:

[0076] .

[0077] in, For average static load, is the cyclic amplitude, and f is the loading frequency.

[0078] The servo systems of each module respond synchronously to component commands within millisecond cycles, thereby physically synthesizing a dynamic vector field with variable direction and continuous amplitude at the anchoring point of the anchor head, accurately simulating the nonlinear mechanical boundary under the effects of tilting pull, cyclic lateral thrust, and wind, wave and current coupling.

[0079] Phase two is the installation phase, characterized by strong coupling and precise penetration control. After the program starts, the control system executes mode A, the first working mode, and runs the core algorithm, namely the dynamic electronic gear coupling algorithm, to control the dual-axis coordinated drive: the disc reduction motor 9 begins to rotate, the loading shaft of the second linear motion mechanism 3 rotates, and the helical anchor 13 is installed and penetrated into the simulated barrel. The vertical linear loading module adjusts the vertical penetration speed of the helical anchor in real time based on encoder feedback, with a speed response accuracy of ±0.1mm / s, controlling the output rotation speed and vertical penetration speed predetermined for the experiment to achieve the installation of the helical anchor.

[0080] Phase three is the loading phase, which involves multi-dimensional vector field reconstruction and interpolation loading. After the helical anchor is installed in place, it enters Mode B, the second working mode. Based on the principle of force vector synthesis, the control system decomposes the set target load vector (such as tilting pull-out force) into horizontal and vertical components. The horizontal linear loading module and the vertical linear loading module are instructed to perform high-precision interpolation linkage, with displacement error controlled within ±0.1mm and force control error controlled within ±1N. This synthesizes linear force or sine / cosine dynamic waveforms at arbitrary angles at the anchor head of the helical anchor 13, realistically reproducing the multi-dimensional coupling effect of wind, waves, and currents on the anchor body in the marine environment.

[0081] Phase four is the array sensing and safety decision-making phase. Existing technologies have limited means of monitoring complex forces. When simulating multi-dimensional composite loading on a helical anchor, the test device and specimen are prone to eccentric loading. Traditional equipment often uses single-point sensors for measurement, lacking a real-time monitoring and protection mechanism for the overall system force balance and eccentric bending moment, which can easily lead to data distortion or even equipment damage. To address this issue, in the above control process, torque sensor 10 and tension / compression sensors 11 continuously collect data. The four arrayed tension / compression sensors 11 monitor in real time for abnormal eccentric bending moments. Once the monitored value exceeds the safety threshold, the system will automatically trigger a shutdown protection to prevent damage to the equipment structure.

[0082] Unlike traditional single-point threshold alarms, this system constructs a mechanical situational awareness and active defense mechanism based on an array-based differential algorithm. The data acquisition unit synchronously acquires the real-time response values ​​f1, f2, f3, and f4 of four tension and compression sensors 11 in the array, defining tension as positive and compression as negative; the distribution radius R from the sensing center of the four tension and compression sensors 11 to the main axis of the system is set as a lever arm constant. The formula for calculating the total axial force is:

[0083] .

[0084] Assuming that sensors 1 and 3 are diagonally opposite each other along the Y-axis, and sensors 2 and 4 are diagonally opposite each other along the X-axis, then the formula for calculating the eccentric bending moment is:

[0085] .

[0086] in, To obtain the eccentric bending moment, R is the lever arm constant. These are the sensing values ​​collected by four tension and compression sensors.

[0087] The bending moment components about the X and Y axes are calculated based on the torque value measured by the torque sensor 10. and In an ideal situation, we have:

[0088] ,Right now:

[0089] .

[0090] Therefore, during the actual operation of the test bench, if If the system is in an asymmetric instability risk state, such as anchor buckling or eccentric loading, the system will immediately trigger the highest priority servo lock command to freeze the current displacement field and unload the driving force.

[0091] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention, and these will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A composite spiral anchor installation and loading test bench, characterized in that, include: Support frame (6), in which simulation component (7) is provided; A rotary drive mechanism (1), which is mounted on the support frame (6), is used to drive the spiral anchor (13) to rotate; The first linear motion mechanism (2) is driven by the rotary drive mechanism (1) and is used to drive the rotary drive mechanism (1) to move along the first direction; The second linear motion mechanism (3) is connected to the rotary drive mechanism (1) and is used to drive the rotary drive mechanism (1) to move along a second direction orthogonal to the first direction; The control system is electrically connected to the rotary drive mechanism (1), the first linear motion mechanism (2) and the second linear motion mechanism (3); The control system is configured as follows: In the first working mode, the rotational motion of the rotary drive mechanism (1) and the linear motion of the second linear motion mechanism (3) are controlled in a coordinated manner based on the dynamic electronic gear coupling algorithm, so that the spiral anchor (13) penetrates the simulation part (7) at a predetermined advance ratio. In the second working mode, the set target load vector is decomposed into a first component along the first direction and a second component along the second direction. Then, the linear / circular interpolation algorithm is called to instruct the first linear motion mechanism (2) and the second linear motion mechanism (3) to perform mixed control of force and displacement.

2. The composite spiral anchor installation and loading test bench according to claim 1, characterized in that, The dynamic electronic gear coupling algorithm is specifically as follows: Establish an electronic gear connection between the loading shaft of the rotary drive mechanism (1) and the loading shaft of the second linear motion mechanism (3); Based on the topological characteristics of the spiral anchor, kinematic constraint equations are established to solve the linear loading velocity and phase linear displacement of the loading axis of the second linear motion mechanism (3). The real-time phase linear displacement is calculated based on the electronic gear coefficient and the real-time angular displacement of the helical anchor. The difference between the calculated phase linear displacement and the real-time phase linear displacement is used to determine whether the loading shaft of the second linear motion mechanism (3) has a displacement deviation; If a displacement deviation occurs, the interpolation of the servo system of the second linear motion mechanism (3) ensures that the position deviation is within the allowable deviation range.

3. The composite spiral anchor installation and loading test bench according to claim 1, characterized in that, If the current simulation is under wave cyclic load, define an objective function: ， Real-time force control is calculated using the following formula: ， The real-time force control is used as the target load vector; in, For average static load, Here, f is the cyclic amplitude, f is the loading frequency, and t is the current time. α is the phase angle of the composite force; α is the incident angle of the force.

4. The composite spiral anchor installation and loading test bench according to claim 1, characterized in that, It also includes an array-type force sensing component; the array-type force sensing component includes four tension and compression sensors (11), the four tension and compression sensors (11) are evenly distributed along the circumferential direction on the force transmission path between the rotary drive mechanism (1) and the helical anchor (13), and the control system is configured to calculate the eccentric bending moment of the helical anchor (13) based on the sensing values ​​collected by the four tension and compression sensors (11).

5. The composite spiral anchor installation and loading test bench according to claim 4, characterized in that, The formula for calculating the eccentric bending moment is: ， in, To obtain the eccentric bending moment, R is the lever arm constant. These are the sensing values ​​collected by four tension and compression sensors.

6. The composite spiral anchor installation and loading test bench according to claim 5, characterized in that, A torque sensor (10) is installed on the loading shaft of the rotary drive mechanism (1). The control system is configured to: convert the torque value M measured by the torque sensor (10) into a bending moment component. and bending moment components And according to the bending moment components and bending moment components Set the eccentricity safety threshold: ； When the calculated eccentric bending moment is greater than the eccentric safety threshold, the system is determined to be in an asymmetric instability risk state, and a servo lock-up command is generated.

7. The composite spiral anchor installation and loading test bench according to claim 4, characterized in that, It also includes a deformation compensation connector (15), which is located between the mounting base (16) of the spiral anchor and the fixing base (14) of the tension and compression sensor.

8. The composite spiral anchor installation and loading test bench according to claim 7, characterized in that, The deformation compensation connector (15) is a single-piece elastic body.

9. A composite spiral anchor installation and loading test bench according to claim 1, characterized in that, The first linear motion mechanism (2) includes two horizontal linear loading modules mounted in parallel on the support frame (6).

10. A composite spiral anchor installation and loading test bench according to claim 9, characterized in that, The second linear motion mechanism (3) includes a mounting bracket (17), on which the sliders of the two horizontal linear loading modules are fixed together. The support frames (6) on both sides of the horizontal linear loading modules are also provided with horizontal guide optical shafts (5). The mounting bracket (17) is slidably connected to the horizontal guide optical shafts (5). Two symmetrically arranged vertical linear loading modules are installed in the mounting bracket (17). The sliders of the two vertical linear loading modules are fixed together with a rotary drive mechanism (1). Vertical guide optical shafts (4) are also fixed at the four corners of the mounting bracket (17). The rotary drive mechanism (1) is slidably connected to the vertical guide optical shafts (4).

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