Anti-scouring composite protection device for offshore wind power pile foundation

Abstract

The invention provides an anti-scouring composite protection device for an offshore wind power pile foundation, and belongs to the field of water conservancy projects. The anti-scouring composite protection device for the offshore wind power pile foundation is a turbulent flow ring arranged on the outer side of the offshore wind power pile foundation in a sleeving mode, the turbulent flow ring is located on the foundation of the offshore wind power pile foundation, and an annular disturbance reduction area is formed between the turbulent flow ring and the offshore wind power pile foundation. According to the anti-scouring composite protection device for the offshore wind power pile foundation, the inclined modeling of the turbulent flow ring is different from the normal vertical modeling, and the inclined part of the inclined modeling can change or guide the original direction of water flow while greatly reducing the speed of the water flow, so that the anti-scouring effect of the offshore wind power pile foundation is improved. And the water flow generates a certain speed in the vertical direction, so that sediment precipitation is accelerated. And the vertical turbulent flow ring with a normal shape can only play a role in reducing the water flow speed and the scouring force.

Description

Technical Field

[0001] The invention provides a composite protective device for preventing scouring of offshore wind power pile foundations, belonging to the field of water conservancy projects. Background Art

[0002] In recent years, environmental pollution, climate change, energy shortage and other problems have been plaguing us. In order to achieve sustainable development of energy, my country has set its sights on the development and utilization of renewable clean energy. Wind energy is one of them, especially offshore wind power generation, which has good development prospects due to its high power generation efficiency, suitability for large-scale development, proximity to coastal power load centers, and no occupation of land. In recent years, China has been the country with the largest scale of newly installed offshore wind power. The single pile foundation has been widely used due to its good effect and easy installation. More than 75% of the pile foundations in the completed offshore wind farms use single pile foundations.

[0003] However, under the action of marine environmental loads, scour pits will be generated around the single pile foundation. If the scour pits are too large, it will seriously affect the safe operation of the wind turbine structure. The local scour of the bed surface around the single pile foundation is mainly caused by the coupling effect between water flow, mud and sand, and pile foundation.

[0004] The local scouring mechanism of the bed surface around the single pile foundation has been studied in depth and considerable results have been achieved. The study found that the horseshoe vortex in front of the pile is the most direct cause of local scouring. When the bed surface shear force caused by the horseshoe vortex in front of the pile reaches the critical shear force of the bed surface mud and sand, the scouring pit begins to form and continuously rolls up the bed surface mud and sand until the scouring balance is reached. Summary of the invention

[0005] In view of the above problems, the present invention provides a composite protective device for preventing scour of offshore wind power pile foundations.

[0006] The present invention adopts the following technical solution:

[0007] The composite protective device for preventing scour of offshore wind power pile foundations described in the present invention is a spoiler ring sleeved on the outside of the offshore wind power pile foundation, and the spoiler ring is located on the foundation of the offshore wind power pile foundation.

[0008] There is a circular disturbance reduction area between the spoiler ring and the offshore wind turbine pile foundation.

[0009] The composite protective device for preventing scour of offshore wind power pile foundation described in the present invention comprises a spoiler ring consisting of an upper part and a lower part; the lower part is a vertical section erected on the foundation of the wind power pile foundation, and the upper part is an inclined section inclined toward the offshore wind power pile foundation; the cross-section of the upper inclined section of the spoiler ring is trapezoidal; and bionic aquatic plants are provided on the outer side of the spoiler ring.

[0010] In the composite protective device for preventing scour of offshore wind power pile foundations described in the present invention, the angle between the inclined section of the spoiler ring and the foundation of the wind power pile foundation ranges from 30° to 50°.

[0011] In the composite protective device for preventing scour of offshore wind power pile foundations described in the present invention, an annular disk is provided between the vertical section of the spoiler ring and the offshore wind power pile foundation, and riprap or bionic water plants are arranged on the annular disk.

[0012] The composite protective device for preventing scour of offshore wind power pile foundations of the present invention comprises a plurality of independent hole slots arranged in the annular disk, and the plurality of hole slots are square or trapezoidal;

[0013] A number of square holes are arranged in a circular matrix with the offshore wind power pile foundation as the center;

[0014] A plurality of trapezoidal slots are arranged in a circle with the offshore wind power pile foundation as the center.

[0015] The composite protective device for preventing scour of offshore wind power pile foundations of the present invention has a plurality of square hole grooves in which bionic water plants or riprap are arranged;

[0016] Bionic water plants or riprap are arranged in several trapezoidal holes.

[0017] In the composite protective device for preventing scour of offshore wind power pile foundations described in the present invention, collars are provided on the inner and outer sides of the vertical section at the lower part of the spoiler ring.

[0018] In the composite protective device for preventing scour of offshore wind power pile foundations described in the present invention, the upper and lower parts of the spoiler ring are formed by pouring concrete, and the outer side of the spoiler ring is wrapped with a steel layer.

[0019] Beneficial Effects

[0020] The composite protective device for offshore wind power pile foundation anti-scouring provided by the present invention adopts an inclined shape of the spoiler ring, which is different from the normal vertical shape. The inclined part of the inclined shape can greatly reduce the speed of the water flow while changing or guiding the original direction of the water flow, so that the water flow has a certain speed in the vertical direction, thereby accelerating the sedimentation. For the vertical spoiler ring of the normal shape, it can only play the role of reducing the water flow speed and the scouring force.

[0021] The composite protective device for preventing scour of offshore wind power pile foundation provided by the present invention adopts a combination of bionic water grass and riprap that can not only reduce the energy of the undercurrent and horseshoe vortex, but also interact with each other, thereby alleviating the sinking damage of the riprap layer and reinforcing the bionic water grass bottom layer. The disadvantages of the two complement each other to form a good effect. Compared with the normal method of combining water grass and riprap, since the spoiler ring has greatly reduced the water flow speed inside the spoiler ring, there is no need to arrange bionic water grass and riprap between the pile foundation and the spoiler ring, which is different from the normal method of arranging full bionic water grass and riprap within a certain range. Therefore, while ensuring good benefits, it is economical and environmentally friendly.

[0022] Secondly, the combination of bionic water plants and riprap reduces the scouring degree around the spoiler ring, thereby increasing the durability of the device and method, and also realizing the linkage and coordination between the devices, making the overall effect more obvious. In a normal anti-scouring device combination, each device operates and functions independently and cannot affect each other or bring benefits.

[0023] The composite protective device for preventing scour of offshore wind power pile foundation provided by the present invention has a spoiler ring wrapped with a stainless steel layer and a concrete cast-in-place pile in the middle of the spoiler ring, which not only ensures the strength of the spoiler ring itself, but also greatly improves its ability to resist seawater corrosion and increases its durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a layout form and structural schematic diagram of the composite protective device for preventing scour of offshore wind power pile foundation of the present invention;

[0025] Figure 2 A schematic diagram of the structure of a spoiler ring of a composite protective device for preventing scour of an offshore wind power pile foundation according to the present invention;

[0026] Figure 3 It is a schematic diagram of a composite protective device for preventing scour of offshore wind power pile foundations containing an annular disk according to the present invention;

[0027] Figure 4 It is a schematic diagram of an annular disk with square holes and slots of the present invention;

[0028] Figure 5 It is a schematic diagram of an annular disk with trapezoidal holes and grooves of the present invention;

[0029] Figure 6 This is a schematic diagram of the anti-scouring principle of the present invention using bionic water plants;

[0030] Figure 7 This is a schematic diagram of the anti-scour principle of using riprap in the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose and technical solution of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] like Figure 1 As shown: a composite protective device for preventing scour of an offshore wind power pile foundation, the protective device is a spoiler ring 2 which is sleeved on the outside of an offshore wind power pile foundation 1, the spoiler ring 2 is located on the foundation 1 of the offshore wind power pile foundation, and a ring-shaped interference reduction area is between the spoiler ring and the offshore wind power pile foundation 1.

[0033] like Figure 2 As shown in the figure: the spoiler ring 2 is composed of an upper part and a lower part; the lower part is a vertical section 3 standing on the foundation of the wind power pile foundation, and the upper part is an inclined section 4 inclined toward the offshore wind power pile foundation; the cross section of the upper inclined section of the spoiler ring 2 is trapezoidal; bionic water plants 5 are arranged outside the spoiler ring 2. The specific arrangement is to install a circle of protective rings that interfere with water flow within a certain range around the pile foundation. The bionic water plants 5 are made of thermoplastic resin material.

[0034] The angle between the inclined section 4 of the spoiler ring 2 and the foundation of the wind turbine pile is in the range of 30° to 50°. The upper part of the spoiler ring is made into a slope with a certain angle to guide the direction of water flow, reduce the flow velocity and facilitate sediment sedimentation. Finally, riprap and bionic water plants are arranged around the pile foundation and the flow ring to reinforce the ground and reduce scouring.

[0035] The inner and outer sides of the vertical section 3 at the lower part of the spoiler ring 2 are provided with collars 8. The upper and lower parts of the spoiler ring 2 are formed by pouring concrete, and a steel layer 9 is wrapped around the outer side of the spoiler ring.

[0036] like Figure 3 As shown: it is another form of the composite protective device for preventing scour of offshore wind power pile foundation of the present invention, the protective device is a spoiler ring 2 set on the outside of the offshore wind power pile foundation 1, the spoiler ring 2 is located on the foundation 1 of the offshore wind power pile foundation, and the spoiler ring and the offshore wind power pile foundation 1 are an annular disturbance reduction area. An annular disk 6 is arranged between the vertical section of the spoiler ring 2 and the offshore wind power pile foundation, and stones or bionic water plants 5 are arranged on the annular disk 6.

[0037] like Figure 4 , Figure 5As shown: a plurality of independent hole slots 7 are provided in the annular disk 6, and a plurality of the hole slots 7 are square or trapezoidal; a plurality of square hole slots 7 are arranged in a circular matrix with the offshore wind power pile foundation as the center; a plurality of trapezoidal hole slots 7 are arranged in a circular matrix with the offshore wind power pile foundation as the center; and bionic water plants or riprap are arranged in a plurality of hole slots.

[0038] like Figure 6 , Figure 7 As shown: The protection principle of the composite protection device for preventing scour of offshore wind power pile foundation of the present invention is as follows:

[0039] After the bottom water flows through the protection area, its flow velocity begins to decrease. Before reaching the vertical part of the spoiler ring, it is blocked by the spoiler ring and the flow velocity is further reduced. A certain recirculation area is formed at the base of the spoiler ring. For the inclined part of the spoiler ring, it first guides the direction of the water flow. In this process, the water flow velocity is reduced due to friction and obstruction. After the water flows through the inclined area, since it still has upward momentum, the water flow continues to move upward and meets the horizontally moving water flow, causing the water flow to move diagonally upward. In addition, part of the water flow flows in a straight line. Due to the greatly reduced flow velocity, it moves diagonally downward. In summary, under the action of the spoiler ring, the speed of the water flow is greatly reduced and its direction is also changed. Therefore, the impact force of the water flow and the strength of the horseshoe vortex formed are greatly reduced. Also, due to the change in the direction of the water flow, the sediment carried by the water flow will be more easily deposited inside the spoiler ring. The bionic water grass and riprap outside the spoiler ring can reduce the energy of the undercurrent and horseshoe vortex to protect the bottom of the spoiler ring. They can also interact with each other to alleviate the sinking damage of the riprap layer and reinforce the bottom of the bionic water grass. The inside of the spoiler ring can protect the base of the seawater wind turbine pile foundation. The disadvantages of the two complement each other and form a good effect. Finally, the collar can protect the spoiler ring well, so that the spoiler ring will not be damaged by a large amount of scouring, and its service life will be extended. Under the combined action of the above-mentioned device combination, the erosion effect in front of the offshore wind turbine pile foundation will be greatly reduced.

[0040] The actual situation was compared with the theoretical model, proving the correctness of the theoretical model. The present invention utilizes existing anti-scouring methods, such as bionic water grass and riprap, and innovates the appearance of the spoiler ring and the sleeve for protecting the spoiler ring, which significantly improves the scouring and erosion of the offshore wind power pile foundation by seawater; it can be arbitrarily applied to a variety of soil environments, and the size of the spoiler ring and the arrangement of the bionic water grass and riprap can be changed, which is flexible.

[0041] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A composite protective device for preventing scour of offshore wind power pile foundation, characterized by: The protective device is a spoiler ring sleeved on the outside of the offshore wind power pile foundation. The spoiler ring is located on the foundation of the offshore wind power pile foundation. There is a circular disturbance reduction area between the spoiler ring and the offshore wind turbine pile foundation.

2. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 1 is characterized by: The spoiler ring consists of an upper part and a lower part; the lower part is a vertical section standing upright on the foundation of the wind power pile foundation, and the upper part is an inclined section inclined toward the offshore wind power pile foundation; the cross-section of the upper inclined section of the spoiler ring is trapezoidal; bionic water plants are arranged on the outside of the spoiler ring.

3. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 2 is characterized by: The angle between the inclined section of the spoiler ring and the wind power pile foundation is in the range of 30° to 50°.

4. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 1 or 2, characterized in that: An annular disk is arranged between the vertical section of the spoiler ring and the offshore wind power pile foundation, and riprap or bionic water plants are arranged on the annular disk.

5. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 4 is characterized by: The annular disk is provided with a plurality of independent slots, and the plurality of slots are square or trapezoidal; A number of square holes are arranged in a circular matrix with the offshore wind power pile foundation as the center; A plurality of trapezoidal slots are arranged in a circle with the offshore wind power pile foundation as the center.

6. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 5 is characterized by: Bionic water plants or riprap are arranged in a number of square holes; Bionic water plants or riprap are arranged in several trapezoidal holes.

7. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 2 is characterized by: Rings are arranged on the inner and outer sides of the vertical section at the lower part of the spoiler ring.

8. The composite protective device for preventing scour of offshore wind power pile foundation according to claim 2 is characterized by: The upper and lower parts of the spoiler ring are formed by pouring concrete, and the outer side of the spoiler ring is wrapped with a steel layer.

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