An experimental device and method for the vibration of submarine cables spanning the sea

Abstract

The present invention discloses a vibration experiment device and method for an overhanging submarine cable. The device includes: a first bracket, a second bracket, a first fixed base, a second fixed base, a test plane, a first flange, a second flange, a first connecting member, a second connecting member, an excitation system, and a data acquisition system; both ends of the sample cable are respectively connected to the flanges, and the flanges are further connected to the brackets through the connecting members. The brackets are adjustably fixed on the test plane through the bases; the excitation system is slidably connected with a plurality of horizontal grooves directly below the sample cable, and is used to provide an excitation load with a preset frequency and a preset amplitude for the sample cable directly above; the data acquisition system is used to collect the tensile force between the flange and the connecting member and the displacement change amount of the sample cable at a preset position. By adopting the embodiment of the present invention, the dynamic response of a long-span submarine cable during vortex-induced vibration underwater can be simulated, and the true simulation of the force condition of the overhanging submarine cable can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of ocean engineering simulation, and particularly relates to a vibration experiment device and method for a suspended submarine cable. Background Art

[0002] Offshore wind power has advantages such as sufficient wind resources, large installed capacity, and less land occupation, and its popularity is increasing globally. As a lifeline, submarine cables play an important role in offshore wind power projects. Due to reasons such as the unevenness of the seabed plane or the long-term erosion and scouring of the seabed caused by ocean currents, submarine cables fixed to pile foundations or laid on the seabed are likely to form suspended spans. The failure of suspended submarine cables under periodic ocean environmental loads needs to be taken seriously. Under certain conditions, when ocean currents pass through the suspended span, vortex shedding will occur, causing it to undergo vortex-induced vibration (VIV) in the cross-flow direction and the along-flow direction. VIV is one of the main factors causing the structural failure of suspended submarine cables. It is necessary to build a prototype test device before the submarine cable is put into practical application to study the force condition and failure law of the submarine cable under vibration conditions.

[0003] Since the response characteristics of a suspended submarine cable under vortex-induced vibration belong to a complex fluid-structure interaction system, factors such as boundary conditions and the shape of the suspended span will affect the force condition of the structure, making it difficult to accurately analyze and calculate the change amplitude and period of the dynamic load on the suspended submarine cable, which will directly affect whether the structure will undergo fatigue failure. However, currently existing devices are all model test vibration devices for analyzing the dynamic characteristics of suspended submarine cables, and cannot directly simulate the force condition of the submarine cable and measure its dynamic response in real time. At the same time, there is also a problem of insufficient accuracy after scaling in model tests. Summary of the Invention

[0004] The present invention provides a vibration experiment device and method for a suspended submarine cable to solve the technical problem that the prior art cannot directly simulate the force condition of the submarine cable in a vibration experiment.

[0005] To solve the above technical problem, an embodiment of the present invention provides a vibration experiment device for a suspended submarine cable, including: a first support, a second support, a first fixed base, a second fixed base, a test plane, a first flange, a second flange, a first connecting member, a second connecting member, an excitation system, and a data acquisition system;

[0006] Wherein, the first end of the sample cable is connected to the first end of the first flange, and the second end of the first flange is connected to the first support through the first connecting member; the second end of the sample cable is connected to the first end of the second flange, and the second end of the flange is connected to the second support through the second connecting member;

[0007] The first bracket and the second bracket are respectively fixed on the first fixed base and the second fixed base;

[0008] There are several horizontal grooves parallel to each other on the test plane. The first fixed base and the second fixed base are respectively fixed on both sides of the several horizontal grooves by bolts; the several horizontal grooves are parallel to the direction of the sample cable;

[0009] The excitation system is slidably connected to the several horizontal grooves directly below the sample cable, and is used to provide an excitation load with a preset frequency and a preset amplitude for the sample cable directly above;

[0010] The data acquisition system is used to acquire the tensile force between the first flange and the first connecting member and the tensile force on the second flange and the second connecting member; and is used to measure the displacement change amount of the sample cable at a preset position.

[0011] In the present invention, the sample cable is kept in a suspended span state through flanges, connecting members, brackets and fixed bases, and the two fixed bases are fixed at preset intervals through several horizontal grooves on the test plane, ensuring that the line shape of the sample cable is consistent with that of the underwater submarine cable; in addition, through the excitation load applied to the sample cable by the excitation system, the dynamic response of the long-span submarine cable during vortex-induced vibration underwater can be simulated; and the data acquisition system can acquire the tensile force at the end of the sample cable and the displacement change amplitude at the preset position of the sample cable, so as to truly simulate the stress condition of the suspended submarine cable in all aspects.

[0012] Further, the excitation system includes: a vibration table, a movable bracket and a controller;

[0013] Wherein, the vibration table is connected to the movable bracket by bolts;

[0014] The movable bracket is slidably connected to the several horizontal grooves;

[0015] The vibration table is used to provide an excitation load with a preset frequency and a preset amplitude for the sample cable directly above;

[0016] The controller establishes a communication connection with the vibration table and is used to set the preset frequency and the preset amplitude.

[0017] The excitation system of the present invention moves the movable bracket in several horizontal grooves, so that the vibration table can adjust the position of the applied excitation load according to different working conditions of the suspended submarine cable, thereby realizing the true simulation of the stress condition of the suspended submarine cable.

[0018] Further, the data acquisition system includes: a force sensor, a laser displacement sensing module and a dynamic data acquisition instrument;

[0019] Among them, the force sensor is installed between the first flange and the first connecting member, and between the second flange and the second connecting member, and is used to collect the tensile force between the first flange and the first connecting member and the tensile force on the second flange and the second connecting member;

[0020] The laser displacement sensing module is fixed at a preset position on the test plane directly below the sample cable, and is used to measure the displacement change of the sample cable at the preset position;

[0021] The dynamic data acquisition instrument is used to obtain the tensile force collected by the force sensor and the displacement change measured by the laser displacement sensing module.

[0022] The force sensor and the laser displacement sensing module of the present invention can respectively collect and measure the end tensile force of the sample cable and the displacement of the sample cable at the preset position, so that the amplitude of the curvature change of the sample cable can be calculated according to the collected displacement data, and the measurement and real simulation of the force condition of the suspended cross-sea cable can be realized.

[0023] Further, the laser displacement sensing module includes: a laser displacement sensor and a clamping bracket;

[0024] Among them, the laser displacement sensor is fixed on the clamping bracket;

[0025] The clamping bracket is fixed at a preset position on the test plane directly below the sample cable.

[0026] Further, the data acquisition system includes: a computer terminal;

[0027] Among them, the computer terminal is communicatively connected to the dynamic data acquisition instrument and is used to store the tensile force and the displacement change.

[0028] Further, the first connecting member and the second connecting member are hinge support connecting members and are respectively movably connected to the second ends of the first flange and the second flange.

[0029] Further, the first connecting member and the second connecting member are fixed connecting members and are respectively fixedly connected to the second ends of the first flange and the second flange.

[0030] The connecting member of the present invention can be selected as a hinge support connecting member to be movably connected to the flange, or a fixed connecting member to be fixedly connected to the flange, so as to simulate the change of the boundary constraint condition of the sea cable, realize the real simulation of the vibration condition of the suspended cross-sea cable, and further analyze the force condition of the sample cable in combination with the excitation system and the data acquisition system.

[0031] Further, the first end of the sample cable is connected to the first end of the first flange, specifically: the first end of the sample cable is hinged to the first end of the first flange through a test joint; the second end of the sample cable is connected to the first end of the second flange, specifically: the second end of the sample cable is hinged to the first end of the second flange through a test joint.

[0032] On the other hand, an embodiment of the present invention further provides a vibration experiment method for a suspended cross-sea cable, which is applied to the vibration experiment device for a suspended cross-sea cable according to any one of the embodiments of the present invention, and includes:

[0033] S1. Fix the first fixed base and the second fixed base on both sides of several horizontal grooves in the test plane at a preset interval, and adjust the connection positions of the first connecting member and the second connecting member on the bracket according to a preset height, so that the suspended span line type of the sample cable is consistent with the line type of the underwater suspended cross-sea cable;

[0034] S2. Apply an excitation load to the sample cable by an excitation system at a preset frequency and a preset amplitude, and calculate the amplitude of the curvature change of the sample cable according to the displacement data collected by the data acquisition system at a preset position; use the data acquisition system to obtain the tension between the first flange and the first connecting member and the tension on the second flange and the second connecting member;

[0035] S3. After adjusting the preset interval, the preset height, the preset frequency and the preset amplitude, repeat S1 - S2.

[0036] The present invention keeps the sample cable in a suspended span state through flanges, connecting members, brackets and fixed bases, and fixes the two fixed bases at a preset interval through several horizontal grooves on the test plane to ensure that the line type of the sample cable is consistent with the line type of the underwater submarine cable; in addition, the excitation load applied to the sample cable by the excitation system can simulate the dynamic response of the long-span cross-sea cable when it undergoes vortex-induced vibration underwater; while the data acquisition system can collect the tension at the end of the sample cable and the amplitude of the displacement change of the sample cable at a preset position, so as to truly simulate the stress condition of the suspended cross-sea cable in all aspects.

[0037] Further, the calculation of the amplitude of the curvature change of the sample cable according to the displacement data collected by the data acquisition system at a preset position is specifically:

[0038] Use the data acquisition system to collect the first displacement at the position of 1 / 4 cable length from the end point of the sample cable, and collect the second displacement at the middle position of the sample cable;

[0039] Calculate the amplitude of the curvature change of the sample cable based on the first displacement, the second displacement, and the horizontal distance component between the position of 1 / 4 cable length from the end point and the middle position; wherein, the expression of the amplitude of the curvature change is:

[0040]

[0041] Wherein, H1 is the first displacement of the sample cable at the position of 1 / 4 cable length from the end point, H2 is the second displacement of the middle position of the sample cable, and l is the horizontal distance component between the position of 1 / 4 cable length from the end point and the middle position. Description of the Drawings

[0042] Figure 1 It is a schematic structural diagram of an embodiment of the vibration experiment device for the suspended cross-sea cable provided by the present invention;

[0043] Figure 2 It is a schematic structural diagram of another embodiment of the vibration experiment device for the suspended cross-sea cable provided by the present invention;

[0044] Figure 3 It is a schematic structural diagram of an embodiment of the excitation system provided by the present invention;

[0045] Figure 4 It is a schematic flow diagram of an embodiment of the vibration experiment method for the suspended cross-sea cable provided by the present invention;

[0046] Among them, the reference numerals in the drawings of the specification are as follows:

[0047] 1. Triangular bracket, 2. Fixed base, 3. Test plane, 4. Hinged connection piece, 5. Flange, 6. Shaking table, 7. Movable bracket, 8. Force sensor, 9. Test joint, 10. Laser displacement sensor, 11. Clamping bracket, 12. Sample cable, 13. Horizontal groove, 14. Controller, 15. Dynamic data acquisition instrument, 16. Computer terminal, 17. Fixed connection piece. Detailed Embodiments

[0048] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0049] Embodiment 1

[0050] Please refer to Figure 1, which is a schematic structural diagram of an embodiment of the vibration experiment device for the suspension submarine cable provided by the present invention, including: a first bracket, a second bracket, a first fixed base, a second fixed base, a test plane, a first flange, a second flange, a first connecting member, a second connecting member, an excitation system and a data acquisition system;

[0051] Wherein, the first end of the sample cable 12 is connected to the first end of the first flange, and the second end of the first flange is connected to the first bracket through the first connecting member; the second end of the sample cable 12 is connected to the first end of the second flange, and the second end of the flange is connected to the second bracket through the second connecting member;

[0052] The first bracket and the second bracket are respectively fixed on the first fixed base and the second fixed base;

[0053] There are several horizontal grooves 13 parallel to each other on the test plane, and the first fixed base and the second fixed base are respectively fixed on both sides of the several horizontal grooves 13 by bolts; the several horizontal grooves 13 are parallel to the direction of the sample cable 12;

[0054] The excitation system is slidably connected to the several horizontal grooves 13 directly below the sample cable 12 for providing an excitation load with a preset frequency and a preset amplitude to the sample cable 12 directly above;

[0055] The data acquisition system is used to collect the tensile force between the first flange and the first connecting member and the tensile force on the second flange and the second connecting member; and is used to measure the displacement change amount of the sample cable 12 at a preset position.

[0056] In this embodiment, the first bracket and the second bracket can be triangular brackets 1.

[0057] In this embodiment, Figure 1 The fixed base 2 includes: a first fixed base and a second fixed base; the flange 5 includes: a first flange and a second flange;

[0058] In this embodiment, the number of the horizontal grooves can be an even number, for example: two.

[0059] In this embodiment, the first connecting member and the second connecting member can be connected to the first bracket and the second bracket respectively by bolts; wherein, the heights at which the first connecting member and the second connecting member are respectively fixed on the first bracket and the second bracket can be adjusted as needed.

[0060] In this embodiment, other fixed bases can be stacked on the first fixed base and the second fixed base to increase the height of the base.

[0061] In the present invention, the sample cable is maintained in a suspended span state through a flange, a connecting member, a bracket, and a fixed base, and two fixed bases are fixed according to a preset spacing through a plurality of horizontal grooves on the test plane, ensuring that the line type of the sample cable is consistent with that of the underwater submarine cable; in addition, the excitation load applied to the sample cable by the excitation system can simulate the dynamic response of the long - span submarine cable during vortex - induced vibration underwater; while the data acquisition system can collect the tensile force at the end of the sample cable and the amplitude of the displacement change at the preset position of the sample cable, thereby achieving a true simulation of the force condition of the suspended - span submarine cable in all aspects.

[0062] Please refer to Figure 3 , which is a schematic structural diagram of an embodiment of the excitation system provided by the present invention. Among them, the excitation system includes: a vibration table 6, a movable bracket 7, and a controller 14;

[0063] Among them, the vibration table 6 is connected to the movable bracket 7 by bolts;

[0064] The movable bracket 7 is slidably connected to the plurality of horizontal grooves 13;

[0065] The vibration table 6 is used to provide an excitation load with a preset frequency and a preset amplitude for the sample cable 12 directly above;

[0066] A communication connection is established between the controller 14 and the vibration table 6, which is used to set the preset frequency and the preset amplitude.

[0067] The excitation system of the present invention moves the movable bracket in a plurality of horizontal grooves, enabling the vibration table to adjust the position where the excitation load is applied according to different working conditions of the suspended - span submarine cable, thereby achieving a true simulation of the force condition of the suspended - span submarine cable.

[0068] Furthermore, the data acquisition system includes: a force sensor 8, a laser displacement sensing module, and a dynamic data acquisition instrument 15;

[0069] Among them, the force sensor 8 is installed between the first flange and the first connecting member, and between the second flange and the second connecting member, and is used to collect the tensile force between the first flange and the first connecting member and the tensile force on the second flange and the second connecting member;

[0070] The laser displacement sensing module is fixed at a preset position on the test plane directly below the sample cable 12, and is used to measure the displacement change of the sample cable 12 at the preset position;

[0071] The dynamic data acquisition instrument 15 is used to obtain the tensile force collected by the force sensor 8 and the displacement change measured by the laser displacement sensing module.

[0072] In this embodiment, the force sensor 8 and the laser displacement sensing module are connected to the dynamic data collector 15 through a data cable.

[0073] The force sensor and the laser displacement sensing module of the present invention can respectively collect and measure the end point tension of the sample cable and the displacement of the sample cable at a preset position, so that the amplitude of the curvature change of the sample cable can be calculated according to the collected displacement data, realizing the measurement and true simulation of the force condition of the suspended cross-sea cable.

[0074] Further, the laser displacement sensing module includes: a laser displacement sensor 10 and a clamping bracket 11;

[0075] Wherein, the laser displacement sensor 10 is fixed on the clamping bracket 11;

[0076] The clamping bracket 11 is fixed at a preset position on the test plane directly below the sample cable 12.

[0077] Further, the data acquisition system includes: a computer terminal 16;

[0078] Wherein, the computer terminal 16 is communicatively connected to the dynamic data collector 15 and is used for storing the tension and the displacement change amount.

[0079] Further, the first connecting member and the second connecting member are hinge connecting members 4 and are respectively movably connected to the second ends of the first flange and the second flange.

[0080] Please refer to Figure 2 , which is a schematic structural diagram of another embodiment of the vibration experiment device for the suspended cross-sea cable provided by the present invention. Among them, the first connecting member and the second connecting member are fixed connecting members 17 and are respectively fixedly connected to the second ends of the first flange and the second flange.

[0081] In this embodiment, the first connecting member and the second connecting member can also be a hinge connecting member 4 and a fixed connecting member 17 respectively. The change of the boundary constraint conditions of the suspended cross-sea cable can be further simulated.

[0082] The connecting member of the present invention can be selected as a hinge connecting member to be movably connected to the flange, or a fixed connecting member to be fixedly connected to the flange, so as to simulate the change of the boundary constraint conditions of the sea cable, realize the true simulation of the vibration working conditions of the suspended cross-sea cable, and further analyze the force condition of the sample cable in combination with the excitation system and the data acquisition system.

[0083] Further, the first end of the sample cable 12 is connected to the first end of the first flange. Specifically, the first end of the sample cable 12 is hinged to the first end of the first flange through a test joint; the second end of the sample cable 12 is connected to the first end of the second flange. Specifically, the second end of the sample cable 12 is hinged to the first end of the second flange through a test joint.

[0084] Please refer to Figure 4 , which is a schematic flow chart of an embodiment of the vibration experiment method for the suspended submarine cable provided by the present invention, mainly including steps S1 - S3, specifically as follows:

[0085] S1. Fix the first fixed base and the second fixed base on both sides of several horizontal grooves in the test plane at a preset spacing, and adjust the connection positions of the first connecting member and the second connecting member on the bracket according to a preset height, so that the suspended span line type of the sample cable is consistent with the line type of the underwater suspended submarine cable.

[0086] S2. Apply an excitation load to the sample cable by an excitation system at a preset frequency and a preset amplitude, and calculate the amplitude of the curvature change of the sample cable according to the displacement data collected by the data acquisition system at a preset position; use the data acquisition system to obtain the tensile force between the first flange and the first connecting member and the tensile force on the second flange and the second connecting member.

[0087] In this embodiment, step S2 is specifically: use the data acquisition system to collect the first displacement at the position of 1 / 4 cable length from the end point of the sample cable, and collect the second displacement at the middle position of the sample cable; calculate the amplitude of the curvature change of the sample cable according to the first displacement, the second displacement, and the distance component in the horizontal direction between the position of 1 / 4 cable length from the end point and the middle position; wherein, the expression of the amplitude of the curvature change is:

[0088]

[0089] wherein, H1 is the first displacement at the position of 1 / 4 cable length from the end point of the sample cable, H2 is the second displacement at the middle position of the sample cable, and l is the distance component in the horizontal direction between the position of 1 / 4 cable length from the end point and the middle position.

[0090] In this embodiment, the first displacement and the second displacement can be measured by respectively setting laser displacement sensing modules at the position of 1 / 4 cable length from the end point of the sample cable and the middle position of the sample cable; and l is the distance between the two laser displacement modules.

[0091] S3. After adjusting the preset spacing, the preset height, the preset frequency, and the preset amplitude, repeat S1 - S2.

[0092] The present invention fills the gap in the field of prototype test devices for simulating the vibration response of suspension sea-crossing cables, and can accurately and comprehensively reflect the force conditions of suspension sea-crossing cables under different vibration conditions; by adopting a distributed modular design, it can be disassembled and installed at will, can flexibly adjust the test plan, has a simple structure and low cost; the present invention can provide a basis for the structural failure analysis of suspension sea-crossing cables, and the designed working conditions can simulate the vibration conditions in real underwater, and can also simulate extreme vibration conditions by changing the boundary constraints.

[0093] The specific embodiments described above further elaborate on the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. In particular, it is pointed out that for those skilled in the art, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An experimental device for the vibration of a suspended submarine cable, characterized in that Comprising: A first bracket, a second bracket, a first fixed base, a second fixed base, a test plane, a first flange, a second flange, a first connecting member, a second connecting member, an excitation system, and a data acquisition system; Wherein, the first end of the sample cable is connected to the first end of the first flange, and the second end of the first flange is connected to the first bracket through the first connecting member; the second end of the sample cable is connected to the first end of the second flange, and the second end of the flange is connected to the second bracket through the second connecting member; The first bracket and the second bracket are respectively fixed on the first fixed base and the second fixed base; There are a number of horizontal grooves parallel to each other on the test plane, and the first fixed base and the second fixed base are respectively fixed on both sides of the number of horizontal grooves by bolts; the number of horizontal grooves is parallel to the direction of the sample cable; The excitation system is slidably connected to the number of horizontal grooves directly below the sample cable, and is used to provide an excitation load with a preset frequency and a preset amplitude for the sample cable directly above; The data acquisition system is used to collect the tension between the first flange and the first connecting member and the tension on the second flange and the second connecting member; and is used to measure the displacement change amount of the sample cable at a preset position.

2. The vibration experiment device for the suspended submarine cable according to claim 1, characterized in that, The excitation system includes: a vibration table, a movable bracket, and a controller; Wherein, the vibration table is connected to the movable bracket by bolts; The movable bracket is slidably connected to the number of horizontal grooves; The vibration table is used to provide an excitation load with a preset frequency and a preset amplitude for the sample cable directly above; The controller establishes a communication connection with the vibration table and is used to set the preset frequency and the preset amplitude.

3. The vibration experiment device for the suspension submarine cable according to claim 1, characterized in that, The data acquisition system includes: a force sensor, a laser displacement sensing module, and a dynamic data acquisition instrument; Wherein, the force sensor is installed between the first flange and the first connecting member, and between the second flange and the second connecting member, and is used to collect the tension between the first flange and the first connecting member and the tension on the second flange and the second connecting member; The laser displacement sensing module is fixed at a preset position on the test plane directly below the sample cable and is used to measure the displacement change amount of the sample cable at a preset position; The dynamic data acquisition instrument is used to obtain the tension collected by the force sensor and the displacement change amount measured by the laser displacement sensing module.

4. The vibration experiment device for the suspended submarine cable according to claim 3, characterized in that The laser displacement sensing module includes: a laser displacement sensor and a clamping bracket; Wherein, the laser displacement sensor is fixed on the clamping bracket; The clamping bracket is fixed at a preset position on the test plane directly below the sample cable.

5. The vibration experiment device for the suspended submarine cable according to claim 3, wherein The data acquisition system includes: a computer terminal; Wherein, the computer terminal is in communication connection with the dynamic data acquisition instrument and is used to store the tension and the displacement change amount.

6. The vibration experiment device for the suspended submarine cable according to any one of claims 1-5, characterized in that, The first connecting member and the second connecting member are hinge connecting members and are respectively movably connected to the second ends of the first flange and the second flange.

7. The vibration experiment device for the suspended submarine cable according to any one of claims 1-5, characterized in that, The first connecting member and the second connecting member are fixed connecting members, and are respectively fixedly connected to the second end of the first flange and the second end of the second flange.

8. The vibration experiment device for the suspended submarine cable according to any one of claims 1-5, characterized in that, The first end of the sample cable is connected to the first end of the first flange. Specifically, the first end of the sample cable is hinged to the first end of the first flange through a test joint; the second end of the sample cable is connected to the first end of the second flange. Specifically, the second end of the sample cable is hinged to the first end of the second flange through a test joint.

9. A vibration experiment method for an overhead submarine cable, characterized in that, Applied to the vibration experiment device for the suspended submarine cable according to any one of claims 1-7, comprising: S1. Fix the first fixed base and the second fixed base on both sides of a plurality of horizontal grooves in the test plane at a preset interval, and adjust the connection positions of the first connecting member and the second connecting member on the bracket according to a preset height, so that the suspended span line type of the sample cable is consistent with the line type of the underwater suspended submarine cable; S2. Apply an excitation load to the sample cable by an excitation system at a preset frequency and a preset amplitude, and calculate the amplitude of the curvature change of the sample cable according to the displacement data collected by the data acquisition system at a preset position; use the data acquisition system to obtain the tension between the first flange and the first connecting member and the tension on the second flange and the second connecting member; S3. After adjusting the preset interval, the preset height, the preset frequency and the preset amplitude, repeat S1-S2.

10. The vibration experiment method for the suspended submarine cable according to claim 9, wherein Calculating the amplitude of the curvature change of the sample cable according to the displacement data collected by the data acquisition system at a preset position, specifically: Using the data acquisition system to collect the first displacement at the position of 1 / 4 cable length from the end point of the sample cable, and collect the second displacement at the middle position of the sample cable; Calculating the amplitude of the curvature change of the sample cable according to the first displacement, the second displacement, and the distance component in the horizontal direction between the position of 1 / 4 cable length from the end point and the middle position; wherein, the expression of the amplitude of the curvature change is: Wherein, H1 is the first displacement at the position of 1 / 4 cable length from the end point of the sample cable, H2 is the second displacement at the middle position of the sample cable, and l is the distance component in the horizontal direction between the position of 1 / 4 cable length from the end point and the middle position.

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