Distributed anchoring foundation suitable for shallow water and high tidal range

Abstract

The invention relates to the technical field of ocean engineering foundation structures, and discloses a distributed anchoring foundation suitable for shallow water and high tidal range, which comprises a suction anchor foundation, a gravity anchor foundation, a pulley assembly, a high-strength mooring chain and a floating body, the invention further provides a construction method of the distributed anchoring foundation suitable for the shallow water and the high tidal range, and the construction method comprises the following steps that S1, according to seabed geological conditions, the penetration depth of the suction anchor foundation and the balance weight parameters of the gravity anchor foundation are determined; s2, the suction anchor foundations are positioned on the left side and the right side of the seabed and fixed in a penetrating mode in a negative pressure mode; s3, a pulley assembly is installed on the gravity anchor foundation, and the gravity anchor foundation is hoisted at a preset position; and S4, mounting a pulley assembly at the bottom of the floating body. The suction anchor foundation and the gravity anchor foundation are combined into a distributed cooperative structure, a stable system with multi-point stress and multi-path force transmission is established, and the technical effects that the dynamic load is adjustable, and the tidal range adaptability is high are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ocean engineering infrastructure, and particularly to a distributed anchoring foundation applicable to shallow water with large tidal range. Background Art

[0002] When constructing ocean floating structures in shallow waters, such as tidal energy power generation devices, observation platforms, surface buoys, etc., it is necessary to face typical environmental characteristics such as limited water depth, significant tidal range, and frequent wave disturbances. With the increasing demand for green energy development and the deployment of offshore engineering equipment in the nearshore area, higher requirements are put forward for the performance of the anchoring foundation system in shallow waters. The anchoring device not only has to withstand the periodic loads caused by waves and tides, but also minimize the disturbance to the seabed structure as much as possible, while taking into account the construction efficiency and the convenience of later maintenance.

[0003] In the existing technology, suction anchor foundations are widely used in soft seabed environments, with the advantages of light structure, short construction period, and high sinking efficiency. Their negative pressure sinking method does not require a large amount of excavation and can quickly form effective anchoring within a certain depth. In addition, gravity anchor foundations rely on their own mass to form anti-slip ability and show good overall stability in areas with flat seabed topography. The two types of anchoring methods can improve the load-bearing capacity of the system by increasing the number of anchor bodies or increasing the weight, and to a certain extent, meet the requirements of the ocean structure foundation, especially suitable for static load control scenarios.

[0004] However, when the above technologies face the complex shallow water areas with drastic tidal range changes and frequent hydrodynamic disturbances, their limitations are gradually exposed. Although the suction anchor is convenient to sink, it is sensitive to the continuity of the seabed. Once it encounters an interlayer or poor drainage, the negative pressure sinking is insufficient, and the long-term service stability will be greatly reduced; although the gravity anchor has stable anti-pulling performance, it is extremely sensitive to wave scouring. Once the bottom is loosened, the whole is prone to slip; most systems adopt a rigid connection method, with a single force transmission path and lack of flexible adjustment ability; once the floating body is subjected to transient impacts caused by tides or wind waves, the load cannot be effectively transferred, easily causing chain breakage or anchor body pulling out, and the anti-fatigue performance of the system is low, and the long-term reliability is difficult to guarantee.

[0005] Therefore, the present invention proposes a distributed anchoring foundation applicable to shallow water with large tidal range to solve the deficiencies of the existing technology. Summary of the Invention

[0006] Aiming at the deficiencies of the existing technology, the present invention provides a distributed anchoring foundation applicable to shallow water with large tidal range, which solves the problems of poor tidal range adaptability, rigid and single force transmission path, and insufficient anti-fatigue ability in the existing technology.

[0007] To achieve the above object, the present invention is realized through the following technical solutions: A distributed anchoring foundation applicable to shallow water with large tidal range includes suction anchor foundations, gravity anchor foundations, pulley assemblies, high-strength mooring chains, and floating bodies. The two suction anchor foundations are respectively arranged on the left and right sides of the seabed. The two ends of the high-strength mooring chain are respectively fixedly connected to the tops of the two suction anchor foundations. A plurality of gravity anchor foundations are arranged between the suction anchor foundations and the floating bodies. Pulley assemblies are arranged on the upper parts of the plurality of gravity anchor foundations. A plurality of pulley assemblies are arranged at the bottom of the floating body. The high-strength mooring chain sequentially passes through each pulley assembly and connects the suction anchor foundation, the gravity anchor foundation, and the floating body to each other.

[0008] Preferably, the suction anchor foundation is a thin-walled cylindrical structure, provided with a drainage valve at the top and an open bottom, and is sunk to the seabed bearing layer by negative pressure.

[0009] Preferably, the gravity anchor foundation is a precast concrete block or a steel box structure, providing anti-slip ability and anti-pull bearing capacity through its own weight.

[0010] Preferably, the pulley assembly includes a pulley, a rotating shaft, and a mounting bracket. The pulley can rotate around the rotating shaft, and the rotating shaft is fixed on the mounting bracket.

[0011] Preferably, through the guiding action of a plurality of pulley assemblies, the high-strength mooring chain realizes the dynamic load transfer and adjustment between the floating body, the gravity anchor foundation, and the suction anchor foundation under the action of tidal rise and fall or wave loads.

[0012] Preferably, the floating body is used to carry external structures or equipment. The pulley assemblies arranged at the bottom of the floating body cooperate with the high-strength mooring chain to reduce the influence of tidal range changes on the floating body.

[0013] Preferably, the pulley assemblies are connected to the gravity anchor foundation and the floating body by flanges, which is convenient for maintenance and replacement.

[0014] A construction method for a distributed anchoring foundation applicable to shallow water with large tidal range includes the following steps:

[0015] S1. According to the seabed geological conditions, determine the penetration depth of the suction anchor foundation and the counterweight parameters of the gravity anchor foundation;

[0016] S2. Position the suction anchor foundations on the left and right sides of the seabed and sink and fix them by negative pressure;

[0017] S3. Install pulley assemblies on the gravity anchor foundations and hoist and place the gravity anchor foundations at the preset positions;

[0018] S4. Install pulley assemblies at the bottom of the floating body;

[0019] S5. Fix the two ends of the high-strength mooring chain to the top of the suction anchor foundation respectively, and pass through each pulley assembly in turn to connect the gravity anchor foundation and the floating body.

[0020] Preferably, the suction anchor foundation is sealed by injecting anti-corrosion filling material after forming negative pressure by pumping water with a water pump.

[0021] The present invention provides a distributed anchoring foundation applicable to shallow water with large tidal differences. It has the following beneficial effects:

[0022] 1. By combining the suction anchor foundation and the gravity anchor foundation into a distributed cooperative structure, the present invention establishes a stable system with multiple-point force application and multi-path force transmission, achieving the technical effects of adjustable dynamic load and strong tidal difference adaptability. Different from the prior art where single-point anchoring is limited and rigid connections are prone to failure, this design avoids the problems of local overloading of the anchor body and fatigue failure of the system.

[0023] 2. The present invention adopts a flexible connection method of pulley assemblies combined with high-strength mooring chains to achieve the active transfer of internal loads of the structure. This design idea is very ingenious. Instead of relying on "rigid connection + rigid resistance" to counter extreme tides, it utilizes the changes of waves and tides themselves to adjust the force transmission path of the system, which is difficult to achieve in existing rigid mooring schemes, and solves the problem of frequent impacts on the anchoring system due to large tidal differences.

[0024] 3. In this scheme, the suction anchor is treated by pumping to form negative pressure and combined with anti-corrosion material sealing, further improving its soil penetration stability and service life. This combined process is convenient and durable in operation, effectively avoiding the problems of interface leakage or failure of traditional suction anchors under repeated tidal level changes, and also eliminating the need for high-frequency maintenance expenses in the later stage.

[0025] 4. The pulley assemblies arranged at the bottom of the floating body of the present invention cooperate with the high-strength mooring chains to construct an adjustable flexible anchoring connection, enabling the floating body to have a certain vertical degree of freedom during the ebb and flow of tides. Compared with traditional rigid connection structures, this design effectively alleviates the abnormal structural stress caused by tidal level changes, avoiding the floating body from floating and lifting at high tide or forming a suspended state at low tide, thereby improving the overall operation stability and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the front view of the distributed anchoring foundation of the present invention under normal working conditions;

[0027] Figure 2 is the front view of the distributed anchoring foundation of the present invention under extreme working conditions;

[0028] Figure 3 is the bottom view of the distributed anchoring foundation of the present invention;

[0029] Figure 4 This is the front view of the pulley assembly of the present invention;

[0030] Figure 5 This is the top view of the pulley assembly of the present invention;

[0031] Figure 6 This is the positive three - axis drawing of the suction anchor foundation of the present invention;

[0032] Figure 7 This is the positive three - axis drawing of the gravity anchor foundation of the present invention;

[0033] Figure 8 This is the schematic flow chart of the construction method of the present invention.

[0034] Among them, 1. Suction anchor foundation; 2. Gravity anchor foundation; 3. Pulley assembly; 31. Pulley; 32. Rotating shaft; 33. Mounting frame; 4. Mooring chain; 5. Floating body. Detailed implementation manners

[0035] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0036] Embodiment 1: Please refer to the attached Figure 1 attachment Figure 3 attachment Figure 4 attachment Figure 5 attachment Figure 6 attachment Figure 7, A distributed anchoring foundation applicable to shallow water with large tidal range, comprising suction anchor foundations 1, gravity anchor foundations 2, pulley assemblies 3, high-strength mooring chains 4 and floating bodies 5. Two suction anchor foundations 1 are respectively arranged on the left and right sides of the seabed. The two ends of the high-strength mooring chain 4 are respectively fixedly connected to the tops of the two suction anchor foundations 1. A plurality of gravity anchor foundations 2 are arranged between the suction anchor foundations 1 and the floating body 5. Pulley assemblies 3 are arranged on the upper parts of the plurality of gravity anchor foundations 2. A plurality of pulley assemblies 3 are arranged at the bottom of the floating body 5. The high-strength mooring chain 4 sequentially passes through each pulley assembly 3 and connects the suction anchor foundations 1, the gravity anchor foundations 2 and the floating body 5 to each other. The suction anchor foundation 1 is a thin-walled cylindrical structure with a drainage valve at the top and an open bottom, and is sunk into the seabed bearing stratum by negative pressure. The gravity anchor foundation 2 is a precast concrete block or a steel box structure, and provides anti-slip ability and anti-pull bearing capacity through its own weight. The pulley assembly 3 includes a pulley 31, a rotating shaft 32 and a mounting bracket 33. The pulley 31 can rotate around the rotating shaft 32, and the rotating shaft 32 is fixed on the mounting bracket 33. Through the guiding action of a plurality of pulley assemblies 3, the high-strength mooring chain 4 realizes the dynamic load transfer and adjustment between the floating body 5, the gravity anchor foundation 2 and the suction anchor foundation 1 under the action of tidal rise and fall or wave load. The floating body 5 is used to carry external structures or equipment. The pulley assembly 3 arranged at the bottom of the floating body 5 cooperates with the high-strength mooring chain 4 to reduce the influence of tidal range change on the floating body 5. The pulley assembly 3 is connected to the gravity anchor foundation 2 and the floating body 5 by flanges, which is convenient for maintenance and replacement.

[0037] Specifically, in this embodiment, a distributed anchoring foundation applicable to shallow water with large tidal range constructs an anchoring system with reasonable structure, balanced mechanical distribution and adaptable to water level changes through the synergistic effect among the suction anchor foundation 1, the gravity anchor foundation 2, the pulley assembly 3, the high-strength mooring chain 4 and the floating body 5. The two suction anchor foundations 1 are symmetrically distributed on the left and right sides of the target seabed area, respectively undertaking the end anchoring function of the whole system. The two ends of the high-strength mooring chain 4 are respectively fixedly connected to the tops of the two suction anchor foundations 1, making it play the role of the main load-bearing cable in the overall structure. A plurality of gravity anchor foundations 2 are arranged between the suction anchor foundations 1 and the floating body 5 at a preset interval. A pulley assembly 3 is installed on the top of each gravity anchor foundation 2 so that the high-strength mooring chain 4 can slide through this area. A pulley assembly 3 is also arranged at the bottom of the floating body 5, so that after the high-strength mooring chain 4 is led out from the suction anchor foundation 1, it sequentially passes through a plurality of pulley assemblies 3 and then returns to the lower part of the floating body 5, and the tensioning stability of the whole system is completed through this layout;

[0038] The suction anchor foundation 1 adopts the form of a thin-walled cylinder, with a drainage valve installed at its top for negative pressure pumping operation, and the bottom remains open so that it can be directly sunk to the seabed bearing layer during the construction process. When the pumping equipment is started, the water inside the suction anchor foundation 1 is pumped out, creating a negative pressure environment that prompts the structure to sink to the target depth and complete its initial anchoring state on the seabed. This structure provides bearing support for vertical uplift forces and some horizontal loads. The gravity anchor foundation 2, on the other hand, adopts a precast concrete block or steel box design, and its weight and layout are optimized according to hydrodynamic conditions and geological distributions to achieve stable reinforcement of the system through its own weight and further bear the vertical and horizontal load transfer generated by the floating body 5. The pulley assembly 3 is a key transition device, including a pulley 31, a rotating shaft 32, and a mounting bracket 33. The pulley 31 can rotate flexibly on the rotating shaft 32 to ensure the smooth movement of the high-strength mooring chain 4. The rotating shaft 32 is firmly supported by the mounting bracket 33 to ensure the overall stiffness and operating stability of the structure;

[0039] Under the action of tidal fluctuations or wave loads, the high-strength mooring chain 4 realizes the flexible transfer of loads between components in the anchoring system through the guiding and adjustment of the pulley assembly 3. This chain not only plays a connecting role in the system structure but also has a dynamic adjustment function, enabling the force relationship between the floating body 5 and the seabed anchoring unit to be automatically adjusted according to changes in water level or environment. The floating body 5, as a platform for carrying external functional modules, has the pulley assembly 3 and the high-strength mooring chain 4 arranged below it working together to achieve force balance, reduce transient impacts, and improve the stability and operating safety of the floating body 5 when waves or tidal differences change. The pulley assembly 3 is connected to the gravity anchor foundation 2 and the floating body 5 by flange connections, which have good versatility and replaceability, and can be quickly disassembled, assembled, and repaired during offshore operation and maintenance, improving the engineering feasibility and maintenance efficiency of the system.

[0040] Example 2: Please refer to the appendix on the basis of Example 1 Figure 2 When the distributed anchoring foundation encounters large tidal changes or extreme climate conditions, due to the rising sea level or increased wave amplitude, a significant vertical uplift force and horizontal displacement trend are generated on the floating body 5. At this time, the gravity anchor foundation 2 originally laid on the seabed surface gradually detaches from its original position under the traction of the high-strength mooring chain 4, thus realizing the active conversion of the functional mode;

[0041] Specifically, when the high-strength mooring chain 4 is driven by the uplift or swaying load of the floating body 5, relying on the guidance and mechanical conversion of the pulley assembly 3, the gravity anchor foundation 2 is gradually pulled away from the seabed. During this process, the pulley 31 rotates on the rotating shaft 32, and the mounting bracket 33 maintains the stability of the structure of the pulley assembly 3, thus ensuring the continuity of the force transmission path. After the gravity anchor foundation 2 is pulled away from the seabed, it will no longer bear the traditional stable support role, but form a suspended state in the water. At this time, its mass and displacement inertia will constitute a swinging system, and then, under the action of hydrodynamic force, it will play a function similar to that of a pendulum mass damper;

[0042] Through this passive response mechanism, the inertial movement of the gravity anchor foundation 2 can absorb part of the impact energy suffered by the floating body 5 under extreme working conditions, and then effectively reduce the peak tension of the high-strength mooring chain 4, relieve the peak transient load borne by the suction anchor foundation 1, and achieve the mechanical rebalancing between different load-bearing units in the anchoring system. At the same time, the gravity anchor foundation 2 provides an operating space for system maintenance or re-layout in the off-bottom state, and can be repositioned through reverse release operation under the conditions allowed by subsequent working conditions, further improving the maintainability and long-term reliability of the system.

[0043] Please refer to the appendix Figure 8 , a construction method for a distributed anchoring foundation applicable to shallow water with large tidal differences, comprising the following steps:

[0044] S1. Determine the penetration depth of the suction anchor foundation 1 and the counterweight parameters of the gravity anchor foundation 2 according to the seabed geological conditions;

[0045] S2. Position the suction anchor foundation 1 on both sides of the seabed and fix it by means of negative pressure penetration;

[0046] S3. Install the pulley assembly 3 on the gravity anchor foundation 2 and hoist and place the gravity anchor foundation 2 at the preset position;

[0047] S4. Install the pulley assembly 3 at the bottom of the floating body 5;

[0048] S5. Fix both ends of the high-strength mooring chain 4 to the top of the suction anchor foundation 1 respectively, and sequentially pass through each pulley assembly 3 to connect the gravity anchor foundation 2 and the floating body 5.

[0049] Specifically, for S1. Drill and take samples and conduct investigation and analysis according to the seabed geological conditions of the engineering sea area, obtain key parameters including soil layer thickness, void ratio, permeability coefficient, etc., and determine the penetration depth of the suction anchor foundation 1 in combination with the tidal difference range, water depth and wave environmental conditions. At the same time, according to the required buoyancy of the floating body 5 and the maximum load demand of the system, optimize the size and counterweight parameters of the gravity anchor foundation 2 to ensure that it has sufficient anti-slip and anti-uplift bearing capacities.

[0050] S2. Use an engineering barge to accurately position the suction anchor foundation 1 on the preset anchor positions on the left and right sides of the seabed, and conduct pumping operations through the water pump system installed on its top. Gradually drain the seawater inside the cylinder to form a sealed negative pressure area, so that the suction anchor foundation 1 sinks to the predetermined design depth by the action of pressure difference. After the sinking is completed, close the top drainage valve, and inject filling materials with anti-corrosion and anti-permeation properties inside the cylinder to improve the stability and tightness of the structure during long-term service.

[0051] S3. Complete the pre-assembly operation of the pulley assembly 3 on land or nearshore platforms, including constructing the pulley 31, the rotating shaft 32, and the mounting bracket 33 into an integrated module, and firmly installing it on the upper structure of the gravity anchor foundation 2. After completing the component installation, use a lifting device to hoist the pre-assembled gravity anchor foundation 2 to the preset position on the seabed, and keep the pulley assembly 3 at an operable height to ensure smooth cable threading in the follow-up.

[0052] S4. Install the pulley assembly 3 at the preset connection node at the bottom of the floating body 5. The pulley assembly 3 and the floating body 5 are connected by flange bolts to ensure stable force. During the installation process, check the rotation flexibility of the pulley 31 and the fastening state of the rotating shaft 32 and the mounting bracket 33 to ensure its reliable operation under dynamic loads in the later stage.

[0053] S5. Fix one end of the high-strength mooring chain 4 to the top of one suction anchor foundation 1, thread it through the pulley assemblies 3 arranged on each gravity anchor foundation 2 and the floating body 5 in sequence according to the predetermined path, and finally fix the other end to the top of the suction anchor foundation 1 on the opposite side. During the threading process, ensure that the tension of the link is reasonable, avoid kinking of the chain links or deviation of the pulleys, and level the whole system to complete the connection and coordinated layout between the floating body 5 and the anchoring foundation system, and construct a complete distributed anchoring bearing system.

[0054] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A distributed anchoring foundation applicable to shallow water with large tidal range, comprising a suction anchor foundation (1), a gravity anchor foundation (2), a pulley assembly (3), a high-strength mooring chain (4) and a floating body (5), characterized in that, Two of the suction anchor foundations (1) are respectively arranged on the left and right sides of the seabed. The two ends of the high-strength mooring chain (4) are respectively fixedly connected to the tops of the two suction anchor foundations (1). A plurality of gravity anchor foundations (2) are arranged between the suction anchor foundation (1) and the floating body (5). Pulley assemblies (3) are arranged on the upper parts of the plurality of gravity anchor foundations (2). A plurality of pulley assemblies (3) are arranged at the bottom of the floating body (5). The high-strength mooring chain (4) sequentially passes through each pulley assembly (3) to connect the suction anchor foundation (1), the gravity anchor foundation (2) and the floating body (5) to each other.

2. The distributed anchoring foundation applicable to shallow water with high tidal range according to claim 1, characterized in that The suction anchor foundation (1) is of a thin-walled cylinder structure, with a drainage valve provided at the top and an open bottom, and is sunk into the seabed bearing stratum by negative pressure.

3. The distributed anchoring foundation applicable to shallow water with high tidal range according to claim 1, characterized in that, The gravity anchor foundation (2) is a precast concrete block or a steel box structure, and provides anti-slip ability and anti-pulling bearing capacity by its own weight.

4. A distributed anchoring foundation applicable to shallow water with large tidal range according to claim 1, characterized in that, The pulley assembly (3) includes a pulley (31), a rotating shaft (32) and a mounting bracket (33). The pulley (31) can rotate around the rotating shaft (32), and the rotating shaft (32) is fixed on the mounting bracket (33).

5. A distributed anchoring foundation applicable to shallow water with high tidal differences according to claim 1, characterized in that, Under the guiding action of a plurality of pulley assemblies (3), the high-strength mooring chain (4) realizes the dynamic load transfer and adjustment among the floating body (5), the gravity anchor foundation (2) and the suction anchor foundation (1) under the action of tidal rise and fall or wave load.

6. A distributed anchoring foundation applicable to shallow water with large tidal range according to claim 1, characterized in that, The floating body (5) is used to carry an external structure or equipment. The pulley assembly (3) arranged at the bottom of the floating body (5) cooperates with the high-strength mooring chain (4) to reduce the influence of tidal difference change on the floating body (5).

7. A distributed anchoring foundation applicable to shallow water with large tidal range according to claim 1, characterized in that, The pulley assembly (3) is connected to the gravity anchor foundation (2) and the floating body (5) by flanges, which is convenient for maintenance and replacement.

8. A construction method for a distributed anchoring foundation applicable to shallow water with large tidal differences, which is applied to a distributed anchoring foundation applicable to shallow water with large tidal differences according to any one of claims 1-7, characterized in that, It includes the following steps: S1. According to the seabed geological conditions, determine the penetration depth of the suction anchor foundation (1) and the counterweight parameters of the gravity anchor foundation (2); S2. Position the suction anchor foundation (1) on the left and right sides of the seabed and sink and fix it by negative pressure; S3. Install the pulley assembly (3) on the gravity anchor foundation (2) and hoist and place the gravity anchor foundation (2) at a preset position; S4. Install the pulley assembly (3) at the bottom of the floating body (5); S5. Fix the two ends of the high-strength mooring chain (4) to the top of the suction anchor foundation (1) respectively, and sequentially pass through each pulley assembly (3) to connect the gravity anchor foundation (2) and the floating body (5).

9. The construction method of a distributed anchoring foundation applicable to shallow water with large tidal range according to claim 8, characterized in that, The suction anchor foundation (1) is sealed by injecting an anti-corrosion filling material after forming a negative pressure by pumping water with a water pump.

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