Aquatic weed sand stabilization and scour prevention structure of submarine cable

Abstract

The utility model discloses a submarine cable waterweed sand stabilization anti-scour structure, which comprises a plurality of stones (1), the plurality of stones (1) are pressed on a dynamic bottoming laying area of a submarine cable (7) along the direction of the submarine cable (7), the stones (1) are provided with through holes (2), waterweed seeds (4) are arranged in the through holes (2), and the waterweed seeds (4) are arranged in the through holes (2). The two ends of the through hole (2) are used for semi-sealing the through hole (2) through cement (3) so as to prevent the aquatic plant seeds (4) from being separated from the through hole (2). According to the aquatic plant sand stabilization and scour prevention structure of the submarine cable, a protection mode of combining aquatic plants and stones can be adopted, and a long-term scour prevention effect is ensured.

Description

Technical Field

[0001] The utility model relates to the field of submarine cable laying, in particular to a waterweed sand fixation and scouring prevention structure for submarine cables. Background Art

[0002] Offshore wind power is a new type of clean energy that uses marine wind energy resources to generate electricity. It has developed rapidly around the world in recent years. Submarine cables are important equipment in offshore wind farms and are the information and energy transmission channels in the entire wind farm operation structure. Submarine cables are used to connect offshore wind turbines, collect and transmit electrical energy, and connect with land power grids.

[0003] During the long-term operation of submarine cables, especially around the foundations of fixed wind power platforms, they will be exposed and suspended due to the impact of ocean currents, and the risk of damage from external forces and mechanical wear of the suspended body will also increase accordingly.

[0004] Therefore, studying the scouring problem of the submarine cable near the pile foundation of offshore wind turbines is very important to ensure the safe operation of offshore wind turbines during their service life. At present, the common pile foundation anti-scouring measures in engineering are traditional riprap protection and sand blanket protection, but these two methods are prone to secondary scouring and require multiple maintenance in the later stage. Summary of the invention

[0005] The technical problem to be solved by the utility model is to provide a water grass sand fixation and anti-scour structure for submarine cables which can adopt a protection method combining water grass and stones to ensure a long-term anti-scour effect.

[0006] The technical solution adopted by the utility model to solve the above-mentioned problem is: a water grass sand fixation and anti-scour structure of a submarine cable, comprising a plurality of stones, wherein the plurality of stones are pressed and covered on the dynamic bottom-touching laying area of ​​the submarine cable along the direction of the submarine cable, the stones are provided with through holes, and water grass seeds are arranged in the through holes, and the two ends of the through holes are semi-closed by cement to prevent the water grass seeds from escaping from the through holes.

[0007] Compared with the prior art, the utility model has the following advantages: first, in the early stage of anti-scouring, the stones have just completed the pressure covering of the submarine cable, and the time affected by the ocean current is short, and they basically remain in the initial position, which can play a sufficient protective role. Then, as time goes by, water grass seeds will grow, and the roots of the water grass will pass through the lower end of the through hole and take root in the seabed, which plays a role in sand fixation, while the stems of the water grass will pass through the upper end of the through hole and sway with the ocean current, which plays an effect of reducing the scouring of the ocean current. At the same time, the water grass can also reduce the impact of the ocean current on the stones and fix the stones. As the water grass grows, the protective effect formed by the water grass will become stronger and stronger, thereby reducing the frequency of maintenance. The design of semi-sealing the two ends of the through hole with cement to prevent the water grass seeds from escaping from the through hole is because the stones can be used to cover the submarine cable by throwing stones. At this time, if the water grass seeds are not designed to prevent detachment, as the stone throwing process, the water grass seeds are prone to detach from the through hole, and the water grass seeds may be far away from the set covering area with the ocean current, and it is difficult to play a protective effect.

[0008] As an improvement of the utility model, the stone is flat, and the through hole is arranged along the axial direction where the stone is thinner. Through the improvement, the flat surface of the flat stone is more likely to be against the seabed when it is finally deposited on the seabed during the stone throwing process, that is, the through hole is more likely to be arranged perpendicular to the seabed when the stone is against the seabed, so that when aquatic plants grow along the through hole, it is easier for them to take root in the seabed and their stems to grow upward.

[0009] As an improvement of the present invention, the water grass seeds are seeds of submerged plants. Through the improvement, the types of water grass seeds are diverse, among which the roots of floating water grass seeds are shallower in the seabed, and their protective effect is slightly worse than that of submerged plants. At the same time, after the stones are against the seabed, the submerged water grass seeds will move downward along the through hole. When taking root, they can complete the rooting action with the seabed faster, which is conducive to better protective effect.

[0010] As an improvement of the utility model, there are a plurality of water grass seeds in one through hole, and the plurality of water grass seeds are wrapped into a ball through a fine mesh. Through the improvement, firstly, the plurality of water grass seeds are arranged in the same through hole, which can increase the probability of water grass growing in each stone, and avoid the situation where individual water grass seeds die and water grass cannot grow on the stone; secondly, after the plurality of water grass seeds grow at the same time, they can be condensed into bundles to improve the protection strength of the water grass; finally, after the water grass is wrapped into a ball, its diameter is larger and it is less likely to fall out of the through hole. The diameter of the through hole of the semi-closed structure of the cement can also be larger, which is conducive to the water grass passing through the cement structure during the growth process.

[0011] As an improvement of the utility model, the fine mesh net adopts soluble fiber cloth. Through the improvement, the fine mesh net serves the purpose of wrapping multiple water grass seeds during the stone throwing process to prevent the water grass seeds from escaping from the through holes. After the stone throwing is completed, the fine mesh net dissolves, and the water grass seeds gathered together begin to disperse, so that they can grow better.

[0012] As an improvement of the utility model, the fine mesh net adopts a low-toughness, low-strength plastic net. Through the improvement, the fine mesh net serves the purpose of wrapping multiple aquatic grass seeds during the stone throwing process to prevent the aquatic grass seeds from escaping from the through holes. After the stone throwing is completed, the aquatic grass seeds begin to grow and break the plastic net to achieve the purpose of growth. The plastic net can be made of a material that is not resistant to seawater corrosion, or a plastic net woven with braided wires containing bubbles.

[0013] As an improvement of the utility model, the diameter of the semi-closed through hole is larger than the diameter of a single aquatic plant seed and smaller than the diameter of a ball of aquatic plant seeds. The improvement is conducive to the rapid growth of multiple aquatic plant seeds after dispersion, while preventing the aquatic plant seeds from escaping from the through hole. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The utility model is a schematic diagram of the cross-sectional structure of a submarine cable covered by stones.

[0015] Figure 2 The utility model is a schematic diagram of the cross-sectional structure of a submarine cable covered by stones.

[0016] Figure 3 It is a schematic diagram of the cross-sectional structure of the stone block of the utility model.

[0017] Figure 4 It is a schematic diagram of the stone structure of the utility model from a top view.

[0018] As shown in the picture: 1. Stone, 2. Through hole, 3. Cement, 4. Aquatic plant seeds, 5. Fine mesh, 6. Pile driver, 7. Cable. DETAILED DESCRIPTION

[0019] The embodiments of the present utility model are further described below in conjunction with the accompanying drawings.

[0020] like Figure 1-4As shown, a water grass sand fixation and anti-scour structure of a submarine cable comprises a plurality of stones 1, wherein the plurality of stones 1 are pressed and laid in a dynamic bottom contacting laying area of ​​the submarine cable 7 along the direction of the submarine cable 7, a through hole 2 is provided on the stone 1, a water grass seed 4 is provided in the through hole 2, and cement 3 is used to semi-close the through hole 2 at both ends of the through hole 2 to prevent the water grass seed 4 from escaping from the through hole 2, the stone 1 is flat, the through hole 2 is arranged along the axial direction where the thickness of the stone 1 is relatively thin, and the water grass seed 4 is seeds of submerged plants.

[0021] The dynamic bottom-touching laying area refers to the area where the cable 7 just extends out of the pile driver 6 and just contacts the seabed. The cable 7 on the side close to the pile driver 6 is protected by the pile driver 6 and is not easily affected by scouring, while the side away from the pile driver 6 has begun to transform from dynamic to static, and the impact of scouring is reduced. Only the cable 7 in this area is most affected by scouring.

[0022] like Figure 3 , Figure 4 As shown, there are a plurality of water grass seeds 4 in one through hole 2, and the plurality of water grass seeds 4 are wrapped into a ball by a fine mesh net 5, and the fine mesh net 5 is made of soluble fiber cloth. The diameter of the through hole 2 after semi-closure is larger than the diameter of a single water grass seed 4 and smaller than the diameter of the water grass seeds 4 wrapped into a ball.

[0023] The fine mesh net 5 can also be a plastic net with low toughness and low strength.

[0024] The stone 1 processing steps are as follows:

[0025] S1: Select a flat stone with high hardness and moderate size;

[0026] S2: Drilling a through hole 2 along the axial direction where the thickness of the stone 1 is relatively thin;

[0027] S3: Use cement 3 to semi-close one end of the through hole 2, leaving space for the aquatic plants to grow out;

[0028] S4: placing the waterweed seeds 4 wrapped by the fine mesh net 5 into the through hole 2;

[0029] S5: The other end of the through hole 2 is also semi-sealed with cement 3 to leave space for the aquatic plants to grow out.

[0030] The steps of stone 1 pressing are as follows:

[0031] S1: Conduct a detailed survey of the seabed topography to determine the laying path of the submarine cable 7 and the dynamic bottom-touching laying area;

[0032] S2: transporting the stone 1 to a designated location via a riprap vessel;

[0033] S3: Throwing stones 1 around the dynamic bottom-touching laying area of ​​the submarine cable 7, and laying it out according to the predetermined drawings and coordinates;

[0034] S4: Visually inspect all stones 1 using an underwater robot to ensure that there is no damage or improper placement;

[0035] S5: Evaluate the functionality of the current layout of stone 1 to ensure that it can effectively protect the submarine cable from scour;

[0036] S6: Assess the impact of construction on the surrounding marine environment to ensure that there will be no excessive impact on the ecosystem;

[0037] S7: Record key steps and results during the construction process to provide reference for subsequent monitoring and maintenance.

[0038] After the construction is completed, in the early stage of riprap, the anti-scour structure is similar to the role and mechanism of traditional riprap protection. The stone 1 has just completed the compression of the submarine cable 7, and is affected by the ocean current for a short time, and basically remains in the initial position, which can play a sufficient protective role. As time goes by, the water grass will further develop, and the roots of the water grass will penetrate from the lower end of the through hole 2 and take root on the seabed, playing a role in fixing sand and stabilizing the seabed. After the water grass is fully developed, the stems of the water grass will penetrate from the upper end of the through hole 2 and sway with the ocean current, which will reduce the surrounding flow rate, reduce ocean current scouring, and settle the silt.

[0039] The above description is only for the best embodiment of the utility model, but it cannot be understood as a limitation of the claims. The utility model is not limited to the above embodiments, and its specific structure is allowed to be changed. All changes made within the protection scope of the independent claims of the utility model are within the protection scope of the utility model.

Claims

1. A waterweed sand fixation and anti-scouring structure for submarine cables, characterized in that: The invention comprises a plurality of stones (1), wherein the plurality of stones (1) are pressed along the direction of a submarine cable (7) in a dynamic bottom-touching laying area of ​​the submarine cable (7), the stones (1) are provided with through holes (2), aquatic weed seeds (4) are arranged in the through holes (2), and cement (3) is used at both ends of the through holes (2) to semi-close the through holes (2) to prevent the aquatic weed seeds (4) from escaping from the through holes (2).

2. According to claim 1, a waterweed sand fixation and anti-scour structure for submarine cables, characterized in that: The stone (1) is flat, and the through hole (2) is arranged along the axial direction where the stone (1) is thinner.

3. The waterweed sand fixation and anti-scour structure for submarine cables according to claim 2, characterized in that: The aquatic grass seeds (4) are seeds of submerged plants.

4. The waterweed sand fixation and anti-scour structure for submarine cables according to claim 1, characterized in that: There are a plurality of waterweed seeds (4) in one through hole (2), and the plurality of waterweed seeds (4) are wrapped into a ball through a fine mesh net (5).

5. The waterweed sand fixation and anti-scour structure for submarine cables according to claim 4, characterized in that: The fine mesh net (5) is made of soluble fiber cloth.

6. The waterweed sand fixation and anti-scour structure for submarine cables according to claim 4, characterized in that: The fine mesh net (5) is a plastic net with low toughness and low strength.

7. The waterweed sand fixation and anti-scour structure for submarine cables according to claim 4, characterized in that: The diameter of the semi-enclosed through hole (2) is larger than the diameter of a single aquatic weed seed (4) and smaller than the diameter of a ball of the aquatic weed seeds (4).

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