L-shaped wind wave flow-earthquake simulation system and method suitable for high gravity field

Abstract

The invention discloses an L-shaped wind wave flow-earthquake simulation system and method suitable for a high gravity field, the simulation system comprises a model box, a wind generation system, an L-shaped wave generation system, a flow generation system and a vibration seabed model, and the model box is used for accommodating and installing each system and is arranged on a rotating arm of a centrifugal machine in an up-and-down swinging manner; the wind generation system is used for forming horizontal airflow circulation, the L-shaped wave generation system is used for generating waves, the flow generation system is used for generating flow, and the vibration seabed model is used for researching interaction between a maritime work structure and seabed soil under various sea conditions. The simulation system can reproduce sea wind, wave, ocean current and earthquake scenes in a high gravity field.

Description

Technical Field

[0001] The present invention belongs to the technical field of marine geotechnical engineering, and particularly relates to an L-shaped wind-wave-current-seismic simulation system and method applicable to a hypergravity field. Background Art

[0002] With the continuous development of China's marine economy and the deepening of marine resource development, the marine environment challenges faced by offshore engineering structures are becoming increasingly complex. Marine environmental factors such as sea breeze, waves, ocean currents, and submarine earthquakes have complex dynamic effects on offshore engineering structures, posing a serious threat to their safe operation. The continuous development of marine engineering has put forward higher requirements for the stability and safety of engineering structures in complex marine environments, and it is necessary to accurately simulate and study the pile-soil mechanical behavior of these structures under the coupled action of wind-wave-current-seismic.

[0003] Regarding the research on the pile-soil mechanical behavior of marine engineering structures, there is currently a lack of an evaluation method for the coupled effect of the multi-process of wind-wave-current-seismic on the structure foundation-seabed. Traditional marine environment simulation systems are often limited to the simulation of a single environmental factor, such as simulating waves or ocean currents separately. There are few devices that can simultaneously simulate multiple environmental factors such as wind, waves, currents, and earthquakes, and these systems usually operate in a conventional gravity field, with the following disadvantages: it is impossible to accurately create a stress field identical to the prototype stress level, resulting in the inability to maintain the consistency of the model stress state, and causing a large difference between the simulation results and the actual situation; in a conventional gravity field, a large model scale is usually required to ensure the accuracy of model tests, resulting in problems such as a large floor area and high test costs.

[0004] Currently, L-shaped pools are widely used in the simulation of complex marine environments, but related model tests are usually carried out in a conventional gravity field, and it is impossible to accurately simulate the mechanical response process of marine engineering structures under the coupled action of complex wind, waves, currents, and earthquakes. Summary of the Invention

[0005] The purpose of the present invention is to provide an L-shaped wind-wave-current-seismic simulation system applicable to a hypergravity field, and a method for simulating L-shaped wind-wave-current-seismic in a hypergravity field based on the above simulation system. The simulation system can reproduce the sea breeze, waves, ocean currents, and seismic scenarios in a hypergravity field, so as to conduct a comprehensive and accurate environmental simulation of offshore engineering structures.

[0006] The technical solution adopted by the present invention is as follows: An L-shaped wind-wave-current-seismic simulation system applicable to a hypergravity field, comprising: The model box (1) is used to accommodate and install various systems and is swingably arranged on the swing arm of the centrifuge (10). It includes a box body (105) and a box cover (101). The box body (105) is successively divided into an upper cavity (102), a lower cavity (103), and a bottom shell (104) from top to bottom. The upper cavity (102) is a water pool with an open top. A groove (1021) protruding downward is provided at the center position of the bottom surface (1022) of the water pool. The groove (1021) extends through the lower cavity (103) into the bottom shell (104). The box cover (101) is detachably and sealingly installed at the upper end of the box body (105). The air-making system (2) is used to form a horizontal air flow circulation above the water surface in the upper cavity (102). Its air inlet (201) and air outlet (202) are arranged on the box cover (101) and face both sides of the upper cavity (102), and the rest is arranged inside the box cover (101). A wind guide plate (208) for changing the wind direction is provided at the air inlet (201). During operation, a circulating wind is formed between the air inlet (201) and the air outlet (202). The L-shaped wave-making system (3) is used to make waves and is installed in the upper cavity (102). The flow-making system (4) is used to make flow. Its water inlet (401) and water outlet (402) are opened on both sides of the bottom surface (1022) of the water pool, and the other parts are installed in the lower cavity (103). During operation, a backflow is formed between the water inlet (401) and the water outlet (402). Flow guide plates for stabilizing the flow field are provided at both the water inlet (401) and the water outlet (402). The vibrating seabed model (5) is used to study the interaction between offshore structures and seabed soil under various sea conditions. It is installed in the groove (1021) and includes a soil seabed (501) for simulating the seabed foundation and installing the offshore structure model (1023), and a vibrating table (502) for vibrating the soil seabed (501) to simulate an earthquake. The soil seabed (501) is flush with the bottom surface (1022) of the water pool.

[0007] Preferably, the bottom surface of the bottom shell (104) is an arc-shaped curved surface (1041). The radian of the arc-shaped curved surface (1041) is consistent with the rotation radian of the model box (1) when the centrifuge (10) rotates and is distributed along the linear trajectory at the farthest end in the rotation state of the model box (1).

[0008] Preferably, in the air-making system (2), an air duct (205) with a rectangular cross-section is arranged inside the box cover (101). The air inlet (201) is connected to the air duct (205) through a blower (204), and the air outlet (202) is connected to the air duct (205) through an exhaust fan (207). The exhaust fan (207) sucks air upward from the air outlet (202) into the upper cavity (102) and sends it to the air duct (205), and the blower (204) receives the air sent from the air duct (205) and sends the air upward into the upper cavity (102) through the air inlet (201), thereby forming a closed-circuit circulation of the air-making airflow. The air guide plate (208) with an adjustable elevation angle at the air inlet is used to change the wind direction, so as to form a horizontal wind in the space of the upper cavity (102).

[0009] Preferably, a honeycomb device (203) is arranged at the air inlet (201), and a gas-liquid separation device (206) is arranged at the air outlet (202).

[0010] Preferably, the L-shaped wave-making system (3) includes a wave-making device, a wave-dissipating structure, and a wave height meter (305); the wave-making device is located on two adjacent inner walls of the upper cavity (102) for generating waves in the upper cavity (102); the wave-dissipating structure is located on the opposite sides of the two wave-making devices on the inner walls of the upper cavity (102) for eliminating wave energy to prevent wave reflection; the wave height meters (305) are distributed in the upper cavity (102) for monitoring the wave-making quality and timely feeding back signals to the unit control system of the wave-making device to correct the movement of the corresponding unit of the wave-making device.

[0011] Preferably, the wave-making device is a bilateral multi-unit wave-making machine, including a longitudinal multi-unit wave-making machine (301) and a transverse multi-unit wave-making machine (302), each including a number of wave-making plates driven by a propulsion device; the longitudinal multi-unit wave-making machine (301) is adjacent to the water inlet (401) of the water flow-making system (4), and the generated waves propagate along the tangential velocity direction of the water when the centrifuge (10) rotates, which is called longitudinal wave-making; the transverse multi-unit wave-making machine (302) is located on the side of the longitudinal multi-unit wave-making machine (301), and the generated waves propagate along the direction of gravity, and the propagation direction is perpendicular to the waves generated by the longitudinal multi-unit wave-making machine (301), which is called transverse wave-making.

[0012] Preferably, the wave-dissipating structure adopts a slope-type variable-aperture wave-dissipating structure.

[0013] Preferably, the wave height meters (305) are fixed on the bottom surface (1022) of the pool in the upper cavity in two groups. One group of wave height meters (305) is installed on the edge of the groove (1021) close to the longitudinal multi-unit wave-making machine (301), and the other group is installed on the edge of the groove (1021) far from the transverse multi-unit wave-making machine (302).

[0014] Preferably, the flow generating system (4) includes a water inlet (401), a water outlet (402), a flow channel (403), a flow generating pump (404), a flow regulating valve (405), a flow meter (406), and flow guiding plates (4011, 4021); the flow channel (403) and the flow generating pump (404) are installed in the lower cavity (103), and the flow guiding plates (4011, 4021) are installed in the upper cavity (102); the water inlet (401) and the water outlet (402) are connected through the flow channel (403), the flow generating pump (404) is arranged on one side of the flow channel (403) close to the water outlet (402), the flow regulating valve (405) is arranged on one side of the flow channel (403) close to the water inlet (401), the flow meter (406) is arranged on the flow channel (403) and is located between the flow generating pump (404) and the flow regulating valve (405), and under the action of the flow generating pump (404), an ocean current is formed on the bottom surface (1022) of the pool in the upper cavity (102).

[0015] Preferably, the water inlet (401) and the water outlet (402) are arranged on the bottom surface (1022) of the pool along the center line of the upper cavity (102) to ensure that the flow generating direction in the upper cavity (102) is consistent with the tangential velocity direction of the water during the rotation of the centrifuge (10).

[0016] Preferably, the flow channels (403) are symmetrically arranged on both sides of the groove (1021) in the space of the lower cavity (103). When the flow channel (403) encounters the groove (1021), it is divided into two branches with the same pipe diameter and length, and the flow meter (406) is installed on the branches of the flow channels (403) on both sides of the groove (1021).

[0017] Preferably, the vibrating seabed model (5) includes a soil seabed (501), a vibrating table (502), and a shock absorption device (503). The soil seabed (501) is installed on the vibrating table (502), and the vibrating table (502) is installed on the bottom plate (1042) of the bottom shell (104) through the shock absorption device (503). The setting of the shock absorption device (503) can reduce the influence of the vibration load on the box body (105).

[0018] An L-shaped wind-wave-current-seismic simulation method in a supergravity field, based on the above-mentioned L-shaped wind-wave-current-seismic simulation system applicable to a supergravity field: According to the gravitational acceleration similarity ratio generated by the centrifuge (10) NDetermine the model scale of the reduced-scale model, then fill the soil seabed (501) into the groove (1021). The thickness of the soil seabed (501) is 1 / N of the thickness of the prototype seabed. Then, determine the test water depth in the upper cavity (102) and fill it with water according to the similarity ratios related to wave generation and current generation. Then, install the marine structure model (1023) after the soil model seabed (501) reaches full saturation. Then, adjust the angle of the air guide plate (208) to ensure that the main wind-receiving position of the marine structure model (1023) is at the center of the horizontal air flow of the wind generation system (2) during the test. Then, install the box cover (101) on the box body (105), and then install the model box (1) on the rotating arm of the centrifuge (10). Then, start the centrifuge (10). After the rotational speed of the centrifuge (10) reaches the target value and operates stably, it generates N times the acceleration of gravity centrifugal acceleration. The model box (1) presents a horizontal state under the action of centrifugal force and is in a super-gravity field. Then, simulate one or more sea conditions of ocean wind, wave, current, and earthquake according to research needs, and monitor the interaction between the soil model seabed (501) and the marine structure model (1023) during the test.

[0019] Preferably, the similarity conditions satisfied by the simulation of ocean wind, wave, current, and earthquake in the super-gravity field include the following: Geometric similarity: (1) (2) In the formula , are the plane geometric scale and the vertical geometric scale respectively, and are applicable to both the wavelength and the wave height; , are the plane geometric length and the vertical geometric length of the model respectively; , are the plane geometric length and the vertical geometric length of the prototype; Gravity similarity: From the Froude number, it can be obtained that (3) (4) (5) (6) In the formula is the Froude number, is the acceleration of gravity in the super-gravity field generated by the centrifuge (10), is the acceleration of gravity in the conventional gravity field, is the flow velocity scale, is the model flow velocity, is the prototype flow velocity; Flow similarity ratio: (7) In the formula is the flow scale.

[0020] Preferably, the soil seabed (501) adopts the prototype soil or prepares model soil with the same or similar physical properties according to the prototype soil; the requirements for the particle size of the soil body for preparing the soil seabed (501) are as follows: the maximum particle size should be less than 1 / 20 - 1 / 10 of the size of the marine structure model (1023); the average particle size is less than 1 / 28 of the size of the marine structure model (1023), and at the same time satisfies being less than 1 / 30 of the smaller size of the main contact surface between the marine structure model (1023) and the soil seabed (501); the thickness of the soil seabed (501) should be 1 / N of the thickness of the prototype seabed, where N is the similarity ratio of the gravitational acceleration generated by the centrifuge (10), and the soil seabed (501) and the prototype seabed should satisfy the formula: (8) In the formula , are the thickness and elastic modulus of the soil seabed (501) respectively, , are the thickness and elastic modulus of the prototype seabed respectively; Select the corresponding soil body according to the research object and research problem. First, conventional indoor geotechnical tests should be carried out to verify the similarity of the physical properties of the model soil and the prototype soil. For model tests with soil strength control, first, it should be ensured that the strength indexes of the model soil and the prototype soil are the same or similar. For model tests with deformation control, first, it should be ensured that the deformation parameters of the model soil and the prototype soil are the same or similar; weigh the model soil of the soil seabed (501) according to the following formula: (9) In the formula is the mass of the model soil, is the density of the model soil, is the volume of the model soil, is the porosity of the model soil.

[0021] Preferably, when it is necessary to simulate the ocean wind: Start the wind generation system (2) to form a closed-loop circulation of the wind generation airflow above the wave water surface of the upper cavity (102). The wind speed is controlled by the PID control algorithm, and the rotational speed is adjusted according to the research needs to control the air volume; When it is necessary to simulate the ocean wave: When a stable target waveform needs to be generated, first generate a longitudinal wave propagating along the linear velocity direction of the water, and reduce the reflection of the longitudinal wave. Observe the wave height meter (305) to monitor the generated waveform. When the generated longitudinal wave is stable, generate a transverse wave propagating along the gravity direction, and reduce the reflection of the transverse wave. Observe the wave height meter (305) to monitor the generated waveform until the longitudinal and transverse wave generation in the hypergravity field reaches the target waveform and operates stably; When simulating ocean currents: According to the flow velocity similarity ratio and the flow rate similarity ratio, determine the flow rate parameters of the hypergravity field model test, start the flow generation system (4), and form a unidirectional flow in the upper cavity (102). The control of the flow rate uses the classical PID control algorithm to ensure the stability of the unidirectional flow; When simulating ocean earthquakes: Start the shaking table (502), and strong earthquakes can be generated on the soil seabed (501) to simulate the process of submarine earthquakes.

[0022] The beneficial effects of the present invention are: This simulation system can integrate the wind generation system (2), the L-shaped wave generation system (3), the flow generation system (4) and the vibrating seabed model (5) in the model box (1). It can not only simulate the dynamic coupling effect of waves and ocean currents, but also simulate the influence of wind fields and earthquakes on offshore engineering structures. Moreover, the model box (1) can be installed on the rotating arm of the centrifuge (10), and the hypergravity field is formed by using the centrifugal simulation technology, so as to reproduce the sea breeze, waves, ocean currents and earthquake scenes in the hypergravity field, simulate the extreme ocean environment, and thus conduct a comprehensive and accurate environmental simulation of offshore engineering structures, providing a high-level test platform for studying the response of offshore engineering structures in complex ocean environments.

[0023] By setting the similarity scale N, and due to the time reduction effect of the scale, this method can realize the simulation of the true working conditions of the prototype under a large-span time within a short time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can also be obtained based on these drawings without creative efforts.

[0025] Figure 1 It is a schematic structural diagram of the L-shaped wind-wave-current-earthquake simulation system applicable to the hypergravity field in the present invention.

[0026] Figure 2 It is a schematic cross-sectional view of the box cover in the present invention.

[0027] Figure 3 It is a top view of the installation of the L-shaped wave generation system, current generation system and vibrating seabed model in the box body of the present invention.

[0028] Figure 4 It is a schematic diagram of the installation of the bottom shell and the vibrating seabed model in the present invention.

[0029] Figure 5 It is a schematic diagram of the model box installed on the centrifuge, and the centrifuge is not started.

[0030] Figure 6 It is a schematic diagram of the model box installed on the centrifuge, and the centrifuge is started.

[0031] Figure 7 It is a schematic diagram of the model box installed on the centrifuge and located in the centrifuge chamber, and the centrifuge is started. Detailed implementation manners

[0032] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are some, but not all, of the embodiments of the present application. Generally, the components of the embodiments of the present application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the scope of protection of the present application.

[0034] It should be noted that: like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0035] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0036] In the description of the present application, it should also be noted that unless otherwise clearly specified and defined, the terms "set", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0037] The features and performance of the present application will be further described in detail below in conjunction with embodiments.

[0038] Embodiment 1 This embodiment discloses an L-shaped wind-wave-current-seismic simulation system applicable to a supergravity field, as Figures 1 to 4 shown, including a model box 1, a wind generation system 2, an L-shaped wave generation system 3, a current generation system 4, and a vibrating seabed model 5. Among them: as Figures 5 to 7 shown, the model box 1 is used to accommodate and install each system and is arranged on the rotating arm of the centrifuge 10 so as to be swingable up and down. As Figure 1 shown, the model box 1 includes a box body 105 and a box cover 101. The box body 105 is successively divided into an upper cavity 102, a lower cavity 103, and a bottom shell 104 from top to bottom. The upper cavity 102 is a pool with an open top. The lower end surface of the upper cavity 102 is the bottom surface 1022 of the pool. The upper cavity 102 is used to hold water and provides space for wave generation, current generation, and air flow circulation on the water surface. A groove 1021 protruding downward is provided at the center position of the bottom surface 1022 of the pool. The groove 1021 extends through the lower cavity 103 into the bottom shell 104. As Figure 1 and Figure 2 shown, the wind generation system 2 is used to form a horizontal air flow circulation above the water surface of the upper cavity 102. Its air inlet 201 and air outlet 202 face the upper cavity 102 and are located on both sides, and the rest are arranged in the box cover 101. A wind guide plate 208 for changing the wind direction is provided at the air inlet 201. When working, a circulating wind is formed between the air inlet 201 and the air outlet 202. As Figure 1 and Figure 3 shown, the L-shaped wave generation system 3 is used for wave generation and is installed in the upper cavity 102. As Figure 1 and Figure 3 shown, the current generation system 4 is used for current generation. Its water inlet 401 and water outlet 402 are opened on both sides of the bottom surface 1022 of the pool, and the rest are installed in the lower cavity 103. When working, a backflow is formed between the water inlet 401 and the water outlet 402. Flow guide plates for stabilizing the flow field are provided at both the water inlet 401 and the water outlet 402. As Figure 1 and Figure 4As shown, the vibrating seabed model 5 is used to study the interaction between offshore structures and seabed soil under various sea conditions. It is installed in the groove 1021 and includes a soil seabed 501 for simulating the seabed foundation and installing the offshore structure model 1023, and a shaking table 502 for vibrating the soil seabed 501 to simulate an earthquake. The soil seabed 501 is flush with the bottom surface 1022 of the water tank, and the pile foundation 1024 of the offshore structure model 1023 directly penetrates into the soil seabed 501.

[0039] Regarding the model box 1: As Figures 1 to 3 shown, in this embodiment: both the box body 105 and the box cover 101 are overall square with equal length and width; the four sides of the box body 105 are rigid side plates, including one observation window made of tempered glass. The setting of the observation window preferably ensures the structural strength and stiffness and facilitates researchers to observe the internal experimental situation of the model box 1; lifting rings are provided at the four corners of the top surface of the box cover 101. During the test, the model box 1 is installed on the hanging basket through the lifting rings, and the hanging basket is swingably installed on the rotating arm of the centrifuge 10.

[0040] In this embodiment: the box cover 101 is detachably and sealedly installed on the upper end of the box body 105 through bolts and seals, which can not only facilitate the installation of each system but also prevent leakage during the test.

[0041] As Figure 1 、 Figure 4 and Figure 7 shown, in this embodiment: the bottom surface of the bottom shell 104 is an arc-shaped curved surface 1041, and the radian of the arc-shaped curved surface 1041 is consistent with the rotation radian of the model box 1 when the centrifuge 10 rotates, and it is distributed along the linear trajectory at the farthest end of the rotation state of the model box 1. This design aims to reduce the distance between the arc-shaped curved surface 1041 and the cylindrical inner wall of the centrifuge chamber 6 when the centrifuge 10 rotates and reduce the wind resistance.

[0042] As Figure 1 and Figure 4 shown, in this embodiment: several cross-shaped supports 1043 are arranged around the groove 1021 in the bottom shell 104 to increase the structural strength of the box body 105.

[0043] Regarding the wind generation system 2: As Figure 1 and Figure 2 shown, in this embodiment: the air inlet 201 and the air outlet 202 are respectively arranged on the left and right sides of the lower end surface of the box cover 101 and are arranged along the center line of the box cover 101.

[0044] As Figure 1 and Figure 2As shown in the figure, in this embodiment: a wind duct 205 with a rectangular cross-section is provided inside the box cover 101. The air inlet 201 is connected to the wind duct 205 through a blower 204, and the air outlet 202 is connected to the wind duct 205 through an exhaust fan 207. The exhaust fan 207 draws air upward into the upper cavity 102 through the air outlet 202 and sends it to the wind duct 205. The blower 204 receives the air sent by the wind duct 205 and sends the air upward into the upper cavity 102 through the air inlet 201, thus forming a closed loop of the air-making air flow. And the air guide plate 208 with an adjustable elevation angle at the air inlet is used to change the wind direction, so as to form a horizontal wind in the space of the upper cavity 102.

[0045] As Figure 1 and Figure 2 shown in the figure, in this embodiment: a honeycomb device 203 is provided at the air inlet 201 to improve the pulsation of the air-making air flow, reduce the air flow turbulence degree, and ensure the uniform and stable air flow velocity of the air-making air flow.

[0046] As Figure 1 and Figure 2 shown in the figure, in this embodiment: a gas-liquid separation device 206 is provided at the air outlet 202 to prevent the water for wave-making and current-making in the upper cavity 102 from being carried by the air flow into the air-making system 2 under storm conditions.

[0047] In this embodiment: the air-making system 2 can produce a controllable wind speed of up to 30 m / s above the wave-making water surface in the upper cavity 102. According to the wind speed grade division, it can simulate the wind speed of level 11, which is 28.5 m / s - 32.6 m / s, belonging to the category of violent storms.

[0048] Regarding the L-shaped wave-making system 3: As Figure 1 and Figure 3 shown in the figure, in this embodiment: the L-shaped wave-making system 3 includes wave-making devices 301, 302, wave-dissipating structures 303, 304, and wave height gauges 305; the wave-making devices 301, 302 are located on two adjacent inner walls of the upper cavity 102 and are used to produce waves in the upper cavity 102; the wave-dissipating structures 303, 304 are located on the opposite sides of the two wave-making devices 301, 302 on the inner walls of the upper cavity 102 and are used to eliminate wave energy and prevent wave reflection; the wave height gauges 305 are distributed in the upper cavity 102 and are used to monitor the wave-making quality and timely feedback signals to the unit control system of the wave-making devices 301, 302 to correct the movement of the corresponding units of the wave-making devices 301, 302.

[0049] As Figure 1 and Figure 3As shown in the figure, in this embodiment: the wave-making devices 301 and 302 are bilateral multi-unit wave-making machines, including a longitudinal multi-unit wave-making machine 301 and a transverse multi-unit wave-making machine 302, each of which includes a number of wave-making plates driven by a propulsion device; the longitudinal multi-unit wave-making machine 301 is adjacent to the water inlet 401 of the flow-making system 4, and the generated waves propagate along the linear velocity direction of the water when the centrifuge 10 rotates, which is called longitudinal wave-making; the transverse multi-unit wave-making machine 302 is located on the side of the longitudinal multi-unit wave-making machine 301, and the generated waves propagate along the direction of gravity, and the propagation direction is perpendicular to the waves generated by the longitudinal multi-unit wave-making machine 301, which is called transverse wave-making.

[0050] As Figure 1 and Figure 3 shown, in this embodiment: the wave-dissipating structures 303 and 304 adopt a slope-type variable-aperture wave-dissipating structure.

[0051] As Figure 3 shown, in this embodiment: the wave gauges 305 are fixed in two groups on the bottom surface 1022 of the water tank in the upper cavity. One group of wave gauges 305 is installed on the edge of the groove 1021 close to the longitudinal multi-unit wave-making machine 301, and the other group is installed on the edge of the groove 1021 far from the transverse multi-unit wave-making machine 302.

[0052] Regarding the flow-making system 4: As Figure 1 and Figure 3 shown, in this embodiment: the flow-making system 4 includes a water inlet 401, a water outlet 402, a flow channel 403, a flow-making pump 404, a flow regulating valve 405, a flow meter 406, and guide plates 4011 and 4021; the flow channel 403 and the flow-making pump 404 are installed in the lower cavity 103, and the guide plates 4011 and 4021 are installed in the upper cavity 102; the water inlet 401 and the water outlet 402 are connected through the flow channel 403, the flow-making pump 404 is arranged on the flow channel 403 close to the water outlet 402, the flow regulating valve 405 is arranged on the flow channel 403 close to the water inlet 401, and the flow meter 406 is arranged on the flow channel 403 and is located between the flow-making pump 404 and the flow regulating valve 405. Under the action of the flow-making pump 404, a water flow closed loop of "water outlet 402 - flow-making pump 404 - flow meter 406 - flow regulating valve 405 - water inlet 401 - upper cavity 102 - water outlet 402" is formed, and this loop forms an ocean current on the bottom surface 1022 of the water tank in the upper cavity 102.

[0053] As Figure 1 and Figure 3 shown, in this embodiment: the water inlet 401 and the water outlet 402 are arranged on the bottom surface 1022 of the water tank along the midline of the upper cavity 102 to ensure that the flow-making direction in the upper cavity 102 is consistent with the linear velocity direction of the water during the rotation of the centrifuge 10.

[0054] AsFigure 1 and Figure 3 As shown in Figure 3 , in this embodiment: the angles of the guide vanes 4011 and 4021 at the water inlet 401 and the water outlet 402 are adjustable, which is used to achieve the control of the steady-state flow field in the upper cavity 102 and improve the flow field uniformity. The included angles between the guide vanes 4011 and 4021 and the bottom surface 1022 of the water tank are determined by the water injection depth in the space of the upper cavity 102.

[0055] As Figure 3 shown, in this embodiment: there should be a straight pipe section of not less than 5 times the inner diameter of the flow channel 403 upstream of the flow meter 406 and a straight pipe section of not less than 3 times the inner diameter of the flow channel 403 downstream to ensure accurate measurement.

[0056] As Figure 3 shown, in this embodiment: the flow channels 403 are symmetrically arranged on both sides of the groove 1021 in the space of the lower cavity 103. When the flow channels 403 encounter the groove 1021, they are divided into two, forming two branch pipes with the same pipe diameter and length. Limited by the space of the lower cavity 103, to meet the installation requirements of the flow meter 406, the flow meter 406 is installed on the branch pipes of the flow channels 403 on both sides of the groove 1021.

[0057] In this embodiment: the flow channel 403 has a circular cross-section, while the water inlet 401 and the water outlet 402 are rectangular openings. Therefore, adapters are provided at the connections between the flow channel 403 and the water inlet 401 and the water outlet 402, and they are connected by flanges.

[0058] Regarding the vibrating seabed model 5: As Figure 1 and Figure 4 shown, in this embodiment: the vibrating seabed model 5 includes a soil seabed 501, a vibrating table 502 and a shock absorption device 503. The soil seabed 501 is installed on the vibrating table 502, and the vibrating table 502 is installed on the bottom plate 1042 of the bottom shell 104 through the shock absorption device 503. The setting of the shock absorption device 503 can reduce the influence of the vibration load on the box body 105.

[0059] This simulation system can integrate the wind generation system 2, the L-shaped wave generation system 3, the flow generation system 4 and the vibrating seabed model 5 in the model box 1. It can not only simulate the dynamic coupling effect of waves and ocean currents, but also simulate the influence of the wind field and earthquakes on offshore engineering structures. Moreover, the model box 1 can be installed on the rotating arm of the centrifuge 10 to form a super-gravity field by using the centrifugal simulation technology, so as to reproduce the sea breeze, waves, ocean currents and earthquake scenes in the super-gravity field, simulate the extreme ocean environment, and thus conduct a comprehensive and accurate environmental simulation of offshore engineering structures, providing a high-level test platform for studying the response of offshore engineering structures in complex ocean environments.

[0060] Embodiment 2 This embodiment discloses a method for simulating L-shaped wind-wave-current-seismic in a hypergravity field, based on the above-mentioned L-shaped wind-wave-current-seismic simulation system applicable to the hypergravity field: According to the gravity acceleration similarity ratio generated by the centrifuge 10 N to determine the model scale of the scaled model, then fill the soil seabed 501 into the groove 1021, and the thickness of the soil seabed 501 is 1 / N of the prototype seabed thickness. Then, determine the test water depth in the upper cavity 102 according to the similarity ratios related to wave generation and current generation and fill it with water. Then, after the soil model seabed 501 reaches full saturation, install the offshore structure model 1023. Then, adjust the angle of the air guide plate 208 to ensure that the main wind-receiving position of the offshore structure model 1023 is at the center of the horizontal air flow of the wind generation system 2 during the test. Then, install the box cover 101 on the box body 105, and then install the model box 1 on the rotating arm of the centrifuge 10. Then, start the centrifuge 10. After the rotation speed of the centrifuge 10 reaches the target value and operates stably, it generates N times the gravitational acceleration of centrifugal acceleration. The model box 1 is in a horizontal state under the action of centrifugal force and is in a hypergravity field. Then, simulate one or more sea conditions of ocean wind, wave, current, and earthquake according to research needs, and monitor the interaction between the soil model seabed 501 - offshore structure model 1023 during the test.

[0061] Specifically, the following steps are adopted: Step 1: According to the gravity acceleration similarity ratio generated by the centrifuge 10 N , determine the model scale of the scaled model This step should comprehensively consider factors such as the capacity of the centrifuge 10, the performance of the test equipment, and the prototype size, and select appropriate similarity criteria according to the research object. The similarity conditions that should be satisfied for the simulation of ocean wind, wave, current, and earthquake in the hypergravity field involved in this application include but are not limited to the following.

[0062] Geometric similarity: (1) (2) In the formula , are the plane geometric scale and the vertical geometric scale respectively, and are applicable to both wavelength and wave height; , are the plane geometric length and the vertical geometric length of the model respectively; , are the plane geometric length and the vertical geometric length of the prototype respectively.

[0063] Gravity similarity: From the Froude number, it can be obtained that (3) (4) (5) (6) In the formula is the Froude number, is the acceleration of gravity in the hypergravity field generated by the centrifuge 10, is the acceleration of gravity in the conventional gravity field, is the velocity scale ratio, is the model flow velocity, is the prototype flow velocity; Flow rate similarity ratio: (7) In the formula is the flow rate scale ratio; The similarity ratios of other commonly used physical quantities in the centrifugal model involved in this application are shown in the following table: Table 1 Other commonly used physical quantities in the centrifugal model

[0064] Step 2. Fill in the soil seabed 501 The material properties of the soil mass in the hypergravity field will not change. Therefore, the materials and physical properties of the soil seabed 501 should be the same as or similar to those of the prototype material. The soil seabed 501 should preferably use the prototype soil, or prepare a model soil with the same or similar physical properties according to the prototype soil.

[0065] The requirements for the particle size of the soil mass for preparing the soil seabed 501 are as follows: The maximum particle size should be less than 1 / 20 - 1 / 10 of the size of the marine structure model 1023; the average particle size is less than 1 / 28 of the size of the marine structure model 1023, and at the same time, it meets the requirement of being less than 1 / 30 of the smaller dimension of the main contact surface between the marine structure model 1023 and the soil seabed 501.

[0066] The thickness of the soil seabed 501 should be 1 / N of the thickness of the prototype seabed, where N is the similarity ratio of the acceleration of gravity generated by the centrifuge 10. The soil seabed 501 and the prototype seabed should satisfy the formula: (8) In the formula , are the thickness and elastic modulus of the soil seabed 501 respectively, , are the thickness and elastic modulus of the prototype seabed respectively.

[0067] Select the corresponding soil mass according to the research object and research question. First, conventional indoor geotechnical tests should be carried out to verify the similarity of the physical properties between the model soil and the prototype soil. Specifically, for the model test with soil strength control, the strength indexes of the model soil and the prototype soil should be the same or similar first. For the model test with deformation control, the deformation parameters of the model soil and the prototype soil should be the same or similar first; Based on the parameters of the soil seabed 501 determined by the above requirements, weigh the model soil of the soil seabed 501 according to the following formula: (9) In the formula is the mass of the model soil, is the density of the model soil, is the volume of the model soil, is the porosity of the model soil.

[0068] Then fill the accurately weighed model soil above the shaker 502 into the groove 1021. The upper surface of the soil seabed 501 is flush with the upper edge of the groove 1021, and the lower surface forms a seal with the installation space of the shaker 502 through a seal to prevent the water and soil in the groove 1021 from leaking into the space of the shaker 502, which may cause wear and corrosion of the shaker 502, reduce the maintenance cost of the shaker 502, and extend the effective working time; Set up a data acquisition system on the shaker 502 to monitor the vibration spectrum generated by the shaker 502 on the soil seabed 501.

[0069] Step 3. Determine the test water depth in the upper cavity 102 and fill it with water First, determine the water depth of the hypergravity field model test according to the similarity ratios related to wave generation and current generation determined in step 1, which mainly involve geometric similarity and gravity similarity, that is, the liquid level height in the upper cavity 102. Then, inject water into the upper cavity 102 until the liquid level gradually rises to the test water depth and stop injecting water. During the water injection process, the guide plates 4011 and 4021 at the water inlet 401 and the water outlet 402 are kept fully open to ensure that the entire space of the flow channel 403 of the current generation system 4 is filled with water. The soil seabed 501 is saturated by the immersion saturation method, and the immersion time should be greater than 24 hours.

[0070] Step 4. After the soil model seabed 501 reaches complete saturation, install the marine structure model 1023 The size of the marine structure model 1023 is determined by the similarity ratio determined in step 1, which mainly involves geometric similarity. The preparation material of the marine structure model 1023 should be the same as the prototype material of the research object.

[0071] After the marine structure model 1023 is installed, install sensors to monitor the force, deformation and displacement of the marine structure model 1023.

[0072] Step 5: Install the cover 101 and the model box 1 First, adjust the angle of the air deflector 208 at the air inlet 201 according to the height of the offshore structure model 1023 to ensure that the main wind-receiving position of the offshore structure model 1023 is at the center of the horizontal air flow of the wind generation system 2 during the test.

[0073] Then, the lifting device uses the lifting ring on the cover 101 to lift the cover 101, slowly move the cover 101 to align the bolt holes of the cover 101 with those of the box body 105, and then install bolts to lock and compress the sealing ring to achieve sealing.

[0074] Then, install the assembled model box 1 on the hanging basket of the rotating arm of the centrifuge 10 using the lifting ring on the cover 101. The hanging basket is installed in a vertically swingable manner. At this time, the centrifuge 10 is in a stationary state without centripetal acceleration, and the model box 1 naturally sags under the action of gravity, as Figure 5 shown in the state.

[0075] Step 6: Start the centrifuge 10 Before starting the centrifuge 10, various safety checks should be carried out, including but not limited to the balance between the model box 1 and the counterweight 9 on the rotating arm of the centrifuge 10, the firm connection between the model box 1 and the rotating arm of the centrifuge 10, the firm connection between the counterweight 9 and the rotating arm of the centrifuge 10, the evacuation of the operator and the emptying of the centrifuge chamber 6, etc.

[0076] Start the centrifuge 10. After the rotational speed of the centrifuge 10 reaches the target value and operates stably, at this time, N times the gravitational acceleration of centripetal acceleration is generated. The model box 1 presents a horizontal state under the action of centrifugal force, as Figure 6 and Figure 7 shown. At this time, the centripetal acceleration field is equivalent to the gravitational acceleration field. Therefore, it can be said that the model box 1 is in a hypergravity field, and the centripetal acceleration at this time is .

[0077] Step 7: Conduct a hypergravity field model test Simulate one or more sea conditions of ocean wind, wave, current, and earthquake according to research needs, and use the monitoring system to effectively monitor the interaction between the soil model seabed 501 - offshore structure model 1023 during the test. The following are several simulated sea conditions.

[0078] When simulating ocean wind: Start the blower 204 to form a closed circulation of the air flow generation above the wave-flow water surface in the upper cavity 102. The blower 204 is frequency-variable controlled, and the wind speed is controlled by the PID control algorithm. The rotational speed is adjusted according to research needs to control the air volume, and a controllable wind speed of up to 30 m / s can be generated above the wave-flow water surface in the upper cavity 102. When the controllable rotational speed of the blower 204 reaches the maximum, an eleven-level sea storm can be simulated.

[0079] When it is necessary to simulate ocean waves: Each wave-making unit of the multi-unit wave maker 301 and the transverse multi-unit wave maker 302 can move synchronously to generate regular waves, solitary waves or random waves according to the wave spectrum, or can move non-synchronously to generate more complex waves. The specific movement process is closed-loop controlled by the control system; when it is necessary to generate a stable target waveform, first start the longitudinal multi-unit wave maker 301 to generate longitudinal waves propagating along the linear velocity direction of the water. The wave-absorbing structure 303 on the opposite side of the longitudinal multi-unit wave maker 301 eliminates the longitudinal wave energy to reduce the reflection of the longitudinal wave. Observe the wave height meter 305 to monitor the generated waveform. After the longitudinal wave generated by the longitudinal multi-unit wave maker 301 is stable, start the transverse multi-unit wave maker 302 to generate transverse waves propagating along the direction of gravity. The wave-absorbing structure 304 on the opposite side of the transverse multi-unit wave maker 302 eliminates the transverse wave energy to reduce the reflection of the transverse wave. Observe the wave height meter 305 to monitor the generated waveform until the longitudinal and transverse wave making in the hypergravity field both reach the target waveform and operate stably.

[0080] When it is necessary to simulate ocean currents: According to the flow velocity similarity ratio and the flow rate similarity ratio determined in step 1, determine the flow rate parameter of the hypergravity field model test, start the flow pump 404 of the flow generation system 4 to form a one-way flow in the upper cavity 102, and monitor the current flow rate value by the flow meter 406 installed on the branch pipe of the flow channel 403; The flow rate passing through the main pipe of the flow channel 403 is calculated by the following formula: (10) In the formula is the main pipe flow rate, is the branch pipe flow rate, which is monitored by the flow meter 406 on the branch pipe; the flow rate calculation of the flow channel satisfies the formula: (11) In the formula is the flow velocity, is the inner diameter of the pipeline; furthermore, the inner diameter of the main pipe of the flow channel 403 and the inner diameters of the branch pipes on both sides of the groove 1021 satisfy the formula: (12) In the formula is the inner diameter of the branch pipe, is the inner diameter of the main pipe; the water flow rate in the upper cavity 102 space: (13) is the width of the upper cavity space, is the water filling depth of the upper cavity space; the monitored value of the flowmeter 406 is known , and the main pipe flow rate can be determined by Formula 10 ; the water flow velocity in the upper cavity 102 space can be calculated by Formula 13: (14) The flow rate is controlled by the classical PID control algorithm. The monitored value of the flowmeter 406 is fed back to the flow-making pump 404 to adjust the flow rate. When the monitored value of the flowmeter 406 reaches the target value and the unidirectional water flow is stable, the flow-making system 4 starts up successfully.

[0081] When it is necessary to simulate a marine earthquake: Start the shaking table 502, and strong earthquakes can be generated on the soil seabed 501 to simulate the process of submarine earthquakes.

[0082] This method can achieve the simulation of the real working conditions of the prototype under a large-span time in a short time by setting the similarity scale N and due to the time-shrinking effect of the scale.

[0083] The embodiments described above are some, but not all, of the embodiments of the present application. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application claimed, but merely represents selected embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts fall within the scope of protection of the present application.

Claims

1. An L-shaped wind-wave-current-seismic simulation system applicable to a hypergravity field, characterized in that Comprising: A model box (1) for accommodating and installing various systems and swingably arranged on the swing arm of a centrifuge (10). It includes a box body (105) and a box cover (101). The box body (105) is successively divided from top to bottom into a mutually separated upper cavity (102), a lower cavity (103), and a bottom shell (104). The upper cavity (102) is a water pool with an open top. A groove (1021) protruding downward is provided at the center of the bottom surface (1022) of the water pool. The groove (1021) extends through the lower cavity (103) into the bottom shell (104). The box cover (101) is detachably and hermetically installed at the upper end of the box body (105); A wind generating system (2) for forming a horizontal air flow circulation above the water surface of the upper cavity (102). Its air inlet (201) and air outlet (202) are arranged on the box cover (101) and face both sides of the upper cavity (102), and the rest is arranged inside the box cover (101). A wind guide plate (208) for changing the wind direction is provided at the air inlet (201). During operation, a circulating wind is formed between the air inlet (201) and the air outlet (202); An L-shaped wave generating system (3) for generating waves, which is installed in the upper cavity (102); A current generating system (4) for generating currents. Its water inlet (401) and water outlet (402) are opened on both sides of the bottom surface (1022) of the water pool, and the other parts are installed in the lower cavity (103). During operation, a return flow is formed between the water inlet (401) and the water outlet (402). Flow guide plates for stabilizing the flow field are provided at both the water inlet (401) and the water outlet (402); A vibrating seabed model (5) for studying the interaction between offshore structures and seabed soil under various sea conditions. It is installed in the groove (1021) and includes a soil seabed (501) for simulating the seabed foundation and installing an offshore structure model (1023), and a vibrating table (502) for vibrating the soil seabed (501) to simulate an earthquake. The soil seabed (501) is flush with the bottom surface (1022) of the water pool; 2. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 1, wherein: The bottom surface of the bottom shell (104) is an arc-shaped curved surface (1041). The radian of the arc-shaped curved surface (1041) is consistent with the rotation radian of the model box (1) when the centrifuge (10) rotates, and is distributed along the linear trajectory at the farthest end of the rotation state of the model box (1).

3. The L-type wind-wave-current-seismic simulation system applicable to a hypergravity field according to claim 1, wherein: In the wind generating system (2), a duct (205) with a rectangular cross-section is arranged inside the box cover (101). The air inlet (201) is connected to the duct (205) through a blower (204), and the air outlet (202) is connected to the duct (205) through an exhaust fan (207). The exhaust fan (207) sucks air from the upper cavity (102) through the air outlet (202) and sends it to the duct (205). The blower (204) receives the air sent by the duct (205) and sends the air to the upper cavity (102) through the air inlet (201), thereby forming a closed loop of the wind generating air flow. And the wind direction is changed by using the wind guide plate (208) with an adjustable elevation angle at the air inlet, so as to form a horizontal wind in the space of the upper cavity (102).

4. The L-type wind wave current-seismic simulation system applicable to a supergravity field according to claim 3, characterized in that: A honeycomb device (203) is provided at the air inlet (201), and a gas-liquid separation device (206) is provided at the air outlet (202).

5. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 1, wherein: The L-shaped wave-making system (3) includes a wave-making device, a wave-damping structure, and a wave height gauge (305); the wave-making device is located on two adjacent inner walls of the upper cavity (102) for generating waves in the upper cavity (102); the wave-damping structure is located on the opposite side of the two wave-making devices on the inner wall of the upper cavity (102) for eliminating wave energy to prevent wave reflection; the wave height gauges (305) are distributed in the upper cavity (102) for monitoring the wave-making quality and timely feeding back signals to the unit control system of the wave-making device to correct the movement of the corresponding unit of the wave-making device.

6. The L-type wind-wave-current-seismic simulation system applicable to a hypergravity field as described in claim 5, wherein: The wave-making device is a bilateral multi-unit wave-making machine, including a longitudinal multi-unit wave-making machine (301) and a transverse multi-unit wave-making machine (302), each including a number of wave-making plates driven by a propulsion device; the longitudinal multi-unit wave-making machine (301) is adjacent to the water inlet (401) of the flow-making system (4), and the generated waves propagate along the linear velocity direction of the water when the centrifuge (10) rotates, which is called longitudinal wave-making; the transverse multi-unit wave-making machine (302) is located on the side of the longitudinal multi-unit wave-making machine (301), and the generated waves propagate along the gravity direction, and the propagation direction is perpendicular to the waves generated by the longitudinal multi-unit wave-making machine (301), which is called transverse wave-making.

7. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 5, characterized in that: The wave-damping structure adopts a slope-type variable-aperture wave-damping structure.

8. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 5, characterized in that: The wave height gauges (305) are fixed on the bottom surface (1022) of the pool in the upper cavity in two groups. One group of wave height gauges (305) is installed on the edge of the groove (1021) close to the longitudinal multi-unit wave-making machine (301), and the other group is installed on the edge of the groove (1021) far from the transverse multi-unit wave-making machine (302).

9. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 1, characterized in that: The flow-making system (4) includes a water inlet (401), a water outlet (402), a flow channel (403), a flow-making pump (404), a flow regulating valve (405), a flowmeter (406), and guide plates (4011, 4021); the flow channel (403) and the flow-making pump (404) are installed in the lower cavity (103), and the guide plates (4011, 4021) are installed in the upper cavity (102); the water inlet (401) and the water outlet (402) are connected through the flow channel (403), the flow-making pump (404) is arranged on the flow channel (403) close to the water outlet (402), the flow regulating valve (405) is arranged on the flow channel (403) close to the water inlet (401), the flowmeter (406) is arranged on the flow channel (403) and is located between the flow-making pump (404) and the flow regulating valve (405), and under the action of the flow-making pump (404), an ocean current is formed on the bottom surface (1022) of the pool in the upper cavity (102).

10. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 9, characterized in that: The water inlet (401) and the water outlet (402) are arranged on the bottom surface (1022) of the pool along the midline of the upper cavity (102) to ensure that the flow-making direction in the upper cavity (102) is consistent with the linear velocity direction of the water during the rotation of the centrifuge (10).

11. The L-type wind-wave-current-seismic simulation system applicable to a supergravity field according to claim 9, characterized in that: The flow channels (403) are symmetrically arranged on both sides of the groove (1021) in the space of the lower cavity (103). When the flow channels (403) encounter the groove (1021), they are divided into two, forming two branch pipes with the same pipe diameter and length. The flow meters (406) are installed on the branch pipes of the flow channels (403) on both sides of the groove (1021).

12. The L-type wind-wave-current-seismic simulation system applicable to the hypergravity field according to claim 1, characterized in that: The vibrating seabed model (5) includes a soil seabed (501), a vibrating table (502) and a shock absorption device (503). The soil seabed (501) is installed on the vibrating table (502), and the vibrating table (502) is installed on the bottom plate (1042) of the bottom shell (104) through the shock absorption device (503). The setting of the shock absorption device (503) can reduce the influence of the vibration load on the box body (105).

13. A simulation method for L-type wind-wave-current-seismic in a supergravity field, characterized in that, L-type wind-wave-current-seismic simulation system applicable to hypergravity field as described in any one of claims 1 to 12: According to the gravitational acceleration similarity ratio generated by the centrifuge (10) N determine the model scale of the scaled model, then fill the groove (1021) with the soil seabed (501), the thickness of the soil seabed (501) is 1 / N of the prototype seabed thickness, then determine the test water depth in the upper cavity (102) and fill it with water according to the similarity ratios related to wave generation and current generation, then install the offshore structure model (1023) after the soil model seabed (501) reaches full saturation, then adjust the angle of the air guide plate (208) to ensure that the main wind-receiving position of the offshore structure model (1023) is at the center of the horizontal wind current of the wind generation system (2) during the test, then install the box cover (101) on the box body (105), then install the model box (1) on the rotating arm of the centrifuge (10), then start the centrifuge (10), after the centrifuge (10) reaches the target speed and runs stably, it generates N times the gravitational acceleration of centrifugal acceleration, the model box (1) presents a horizontal state under the action of centrifugal force and is in a hypergravity field, then simulate one or more sea conditions of ocean wind, wave, current, and earthquake according to research needs, and monitor the interaction between the soil model seabed (501) - offshore structure model (1023) during the test.

14. The L-type wind-wave-current-seismic simulation method in a supergravity field according to claim 13, characterized in that, The similarity conditions satisfied by the simulation of ocean wind, wave, current and earthquake in the hypergravity field include the following types: Geometric similarity: (1) (2) where and are the plane geometric scale and the vertical geometric scale respectively, and are applicable to both the wavelength and the wave height; and are the plane geometric length and the vertical geometric length of the model respectively; and are the plane geometric length and the vertical geometric length of the prototype. Gravity similarity: From the Froude number, (3) (4) (5) (6) In the formula is the Froude number, is the gravitational acceleration in the hypergravity field generated by the centrifuge (10), is the gravitational acceleration in the conventional gravity field, is the flow velocity scale, is the model flow velocity, is the prototype flow velocity; Flow rate similarity ratio: (7) In the formula is the discharge scale.

15. The L-type wind-wave-current-seismic simulation method in a supergravity field according to claim 13, wherein The soil seabed (501) uses the prototype soil or prepares a model soil with the same / similar physical properties according to the prototype soil; the requirements for the particle size of the soil body for preparing the soil seabed (501) are as follows: the maximum particle size should be less than 1 / 20 - 1 / 10 of the size of the marine structure model (1023); the average particle size is less than 1 / 28 of the size of the marine structure model (1023), and at the same time, it meets the requirement of being less than 1 / 30 of the smaller size of the main contact surface between the marine structure model (1023) and the soil seabed (501); the thickness of the soil seabed (501) should be 1 / N of the thickness of the prototype seabed, where N is the similarity ratio of the gravitational acceleration generated by the centrifuge (10). The soil seabed (501) and the prototype seabed satisfy the formula: (8) where , are the thickness and elastic modulus of the soil seabed (501) respectively, , are the thickness and elastic modulus of the prototype seabed respectively; Select the corresponding soil body according to the research object and research problem. First, carry out conventional indoor geotechnical tests to verify the similarity of the physical properties between the model soil and the prototype soil. For the model test with soil strength control, first, it should be ensured that the strength indexes of the model soil and the prototype soil are the same or similar. For the model test with deformation control, first, it should be ensured that the deformation parameters of the model soil and the prototype soil are the same or similar; weigh the model soil of the soil seabed (501) according to the following formula: (9) In the formula is the mass of the model soil, is the density of the model soil, is the volume of the model soil, is the porosity of the model soil.

16. The L-type wind-wave-current - earthquake simulation method in the hypergravity field according to claim 13, characterized in that: When simulating ocean wind: Start the wind generation system (2) to form a closed circulation of the wind generation airflow above the wave water surface in the upper cavity (102). The control of the wind speed uses the PID control algorithm, and the rotational speed is adjusted according to the research needs to control the air volume; When simulating ocean waves: When generating a stable target waveform, first generate a longitudinal wave propagating along the linear velocity direction of the water and reduce the reflection of the longitudinal wave. Observe the wave height meter (305) to monitor the generated waveform. When the generated longitudinal wave is stable, generate a transverse wave propagating along the gravitational direction and reduce the reflection of the transverse wave. Observe the wave height meter (305) to monitor the generated waveform until both the longitudinal and transverse wave generation in the hypergravity field reach the target waveform and operate stably; When simulating ocean currents: Determine according to the flow velocity similarity ratio and the flow rate similarity ratio the flow rate parameter of the high gravity field model test, start the flow generating system (4), form a unidirectional flow in the upper cavity (102), and adopt the classical PID control algorithm to control the flow rate to ensure the stability of the unidirectional flow of water; When simulating ocean earthquakes: Start the vibrating table (502), and strong earthquakes can be generated on the soil seabed (501) to simulate the process of submarine earthquakes.

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