Offshore wind power single pile foundation scale bionic scour prevention device and construction method

Abstract

The application discloses a kind of offshore wind power single-pile foundation scale biomimetic scour prevention devices and construction methods, the biomimetic scour prevention device includes fixed chain net, fixed chain net includes mutually nested inner chain ring and outer chain ring, both are connected by chain, and multiple chains are spaced along the circumferential direction of inner chain ring and outer chain ring;The area between adjacent two chains constitutes scale unit;Scale unit includes several scour prevention scales and tail embedded scales, several scour prevention scales are connected by left-right staggered connection, and are connected by inner chain ring to outer chain ring direction to form scour prevention scale whole;Scour prevention scale adjacent to outer chain ring is connected between outer chain ring by tail embedded scale;Several scour prevention scales and tail embedded scales jointly form scale unit similar to animal scale.The connection between scour prevention scale and scale unit and fixed chain net of the present application makes the structure have deformation ability, can fix the soil around pile to prevent surface sand loss and form scour pit.

Description

Technical Field

[0001] The present invention relates to an anti-scour device and a construction method, and in particular to an offshore wind power monopile foundation scale bionic anti-scour device and a construction method. Background Art

[0002] Offshore wind power refers to the construction of wind turbines in the ocean, generating electricity through wind-driven wind turbines. Compared to onshore wind power, offshore wind power offers advantages such as abundant wind resources, less land occupation, and reduced noise and visual pollution. However, it also presents challenges such as high construction and maintenance costs, technical difficulties, and power transmission difficulties. Monopile foundations are a common foundation type for offshore wind turbines, particularly in relatively shallow waters. This foundation type is widely used due to its simple structure, ease of construction, and relatively low cost.

[0003] At present, due to the action of waves and tides, the mud and sand around the offshore wind power single pile foundation will be washed away and form scour pits. The scour pits will significantly reduce the embedding depth of the pile foundation, seriously affecting the working performance and safe operation of the pile foundation. The anti-scour devices currently used for offshore wind power pile foundations are mostly block-shaped parabolic objects such as riprap and sand blankets. Due to the lack of effective connection between the scattered particles, they are easily affected by the transportation of ocean currents. The anti-scour effect gradually weakens with the reduction of effective parabolic objects, and the parabolic objects need to be replenished regularly, resulting in high maintenance costs. The existing technology involves connecting parabolic objects through materials such as chain nets, but there are also problems such as the parabolic objects being heavy, large in size, easy to deform, and difficult to construct, making them difficult to promote and apply.

[0004] Therefore, there is an urgent need for a new anti-scour device with good anti-scour effect, lightweight, easy construction, low cost and high horizontal rigidity. Summary of the Invention

[0005] Purpose of the invention: The purpose of the present invention is to provide an offshore wind power monopile foundation scale bionic anti-scour device with good anti-scour effect, lightweight, easy construction, low cost and high horizontal stiffness;

[0006] The second object of the present invention is to provide a construction method for the above-mentioned offshore wind power single pile foundation scale bionic anti-scour device.

[0007] Technical solution: The offshore wind power single pile foundation scale bionic anti-scour device described in the present invention includes a fixed chain net for being sleeved on the periphery of the single pile foundation, the fixed chain net includes an inner chain ring and an outer chain ring that are nested with each other, the inner chain ring and the outer chain ring are connected by chains, and multiple chains are arranged at intervals along the circumference of the inner chain ring and the outer chain ring; the area between two adjacent chains constitutes a scale armor unit; the scale armor unit includes a number of anti-scour scales and tail embedded scales, and the several anti-scour scales are connected by left and right staggered connection, and are connected from the inner chain ring to the outer chain ring to form an anti-scour scale as a whole; the anti-scour scales adjacent to the outer chain ring are connected to the outer chain ring by the tail embedded scales; the several anti-scour scales and the tail embedded scales together form a scale armor unit shaped like animal scales.

[0008] Among them, the anti-scour scales are in a three-fold shape, including a first front folding plate, a first middle folding plate and a first rear folding plate; the first front folding plate is provided with a first hole for connecting the anti-scour scales with the inner chain ring and between the front and back of several anti-scour scales, the first rear folding plate is provided with a second hole for connecting the front and back of several anti-scour scales and between the anti-scour scales and the tail embedded scales, and the first middle folding plate is provided with a first groove for connecting several anti-scour scales left and right.

[0009] Among them, the tail embedded scales are in an inverted U-shaped three-fold shape, including a second front folding plate, a second middle folding plate and a second rear folding plate; the second front folding plate is provided with a third hole for connecting the anti-scour scales with the tail embedded scales, the second rear folding plate is provided with a fourth hole for connecting the tail embedded scales with the outer chain ring, and the second middle folding plate is provided with a second groove for connecting several tail embedded scales on the left and right.

[0010] Among them, the inner chain ring and the anti-scour scales, between adjacent anti-scour scales, between the anti-scour scales and the tail embedded scales, between the tail embedded scales and the outer chain ring, and between the chain and the anti-scour scales located at the edge of the scale armor unit are respectively connected by connecting buckles, which are used to connect each scale armor unit into a fixed chain net; the above-mentioned connection is a flexible connection, so that the structure has a certain deformation ability, and can adapt to the concave surface when part of the sand and soil around the pile body is lost and a depression is formed, thereby fixing the soil around the pile to prevent surface sand and soil from being lost and forming a scour pit.

[0011] Wherein, the inner chain ring and the outer chain ring are both polygonal; the top edge of the scale armor unit is similar to the side length of the inner chain ring, and the bottom edge is similar to the side length of the outer chain ring.

[0012] Wherein, the scale armor unit is a trapezoidal structure, preferably an isosceles trapezoidal structure.

[0013] Among them, the inscribed circle diameter of the inner chain ring is the cross-sectional diameter of the single pile, and the inscribed circle diameter of the outer chain ring is ~ times the cross-sectional diameter of the single pile.

[0014] Among them, the anti-scouring scales and the tail embedded scales are all made of steel, with a thickness of 6 to 8 mm and a folding angle of 10° to 30°.

[0015] Each chain is connected to the outer chain ring through a lifting ring.

[0016] The construction method of the above-mentioned offshore wind power monopile foundation scale bionic anti-scour device includes the following steps:

[0017] (A) Connect several chains to the outer chain loops. Disconnect one chain from the inner and outer chain loops at one end of the adjacent chain to create a reserved opening for installation around the monopile foundation. Assemble several anti-scour scales and tail embedded scales to form armor units. Transport the units to the installation site.

[0018] (B) linking the armor units to chains to form a fixed chain net, so that the reserved openings of the fixed chain net surround the single pile foundation on both sides;

[0019] (C) Close the reserved openings to form a complete device, lift the device, and slowly release it to the seabed to complete the installation.

[0020] Among them, for existing foundations that have already produced large scour pits, the scour pits are filled first and then the device is installed.

[0021] Beneficial effects: Compared with the prior art, the present invention achieves the following significant effects:

[0022] (1) Good anti-scour effect: The scales are connected in series to form an anti-scour layer with certain flexibility in the vertical direction and sufficient rigidity in the horizontal direction. This anisotropic rigidity characteristic ensures that the device can adapt to the undulating surface of the seabed and can be firmly adsorbed on the seabed without being affected by ocean currents. Compared with the existing technology, there is no need to set anti-slip rivets, and the anti-scour effect is higher.

[0023] (2) Induced sedimentation protection: The unique Z-shaped surface of the scales can consume the kinetic energy of the water flow and reduce the water flow rate. At the same time, the two grooves set in the middle of the scales increase the flow path of the water flow, inducing the insoluble matter in the water flow to form an accumulation in the grooves. The accumulation body covers the scales to strengthen the anti-scour effect of the device. It can allow the sediment brought by the water flow to enter the interior of the structure, so that some of the sediment in the water flow is deposited on the surface of the original soil layer inside the structure, playing a role in reinforcing the original soil layer.

[0024] (3) Adapt to irregular terrain and inhibit the development of existing scour pits: The steel plate scales of the structure are connected to each other by linking buckles, not fixed connections, and the scales as a whole are also connected to the fixed chain by linking buckles, so that the structure has a certain deformation and coordination ability like animal scales, and can fit the undulating surface around the covering foundation and existing small scour pits, preventing the scour pits from continuing to expand.

[0025] (4) Low manufacturing and operation and maintenance costs: The device is assembled from small-sized scales and can be prefabricated on a large scale in onshore factories. The buckles and chains use current mature processes, and steel consumption is reduced by drilling holes in the scales, resulting in low manufacturing costs. Compared with traditional methods such as riprap and sandbags, the device is lightweight, compact, easy to deploy, has low transportation costs, and is reusable. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic structural diagram of the anti-scour device of the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of a single scale armor unit and a fixed chain net of the present invention;

[0028] Figure 3 for Figure 2 A partial enlarged schematic diagram of a single scutellar unit;

[0029] Figure 4 This is a schematic diagram of the connection of the anti-scour scales of the steel plate of the present invention;

[0030] Figure 5 This is a three-dimensional schematic diagram of the assembly of the anti-scour scales of the steel plate of the present invention;

[0031] Figure 6 This is a three-dimensional schematic diagram of the anti-scour scales of the steel plate of the present invention;

[0032] Figure 7 This is a three-dimensional schematic diagram of the tail embedded scales of the present invention;

[0033] Figure 8 A three-dimensional schematic diagram of the link buckle of the present invention;

[0034] Figure 9 This is a schematic diagram of the assembly structure of the anti-scour device of the present invention;

[0035] Figure 10 This is a front schematic diagram of the device of the present invention in the sinking stage;

[0036] Figure 11 It is a schematic top view of the device of the present invention during the sinking stage. DETAILED DESCRIPTION

[0037] The present invention is described in further detail below.

[0038] like Figures 1 to 8 As shown, the present invention discloses a bionic scale anti-scour device for offshore wind power monopile foundations, comprising a fixed chain net 1; the fixed chain net 1 comprises an inner chain ring 101 and an outer chain ring 103 that are nested with each other, the inner chain ring being used to be mounted on a tower 7; the corresponding corner points of the inner chain ring 101 and the outer chain ring 103 are connected by chains 102, and the area between two adjacent chains 102 constitutes a scale armor unit. Each scale armor unit comprises a plurality of interconnected anti-scour scales 2, the anti-scour scales 2 and the outer chain ring 103 being connected by tail embedded scales 3; adjacent anti-scour scales 2, as well as the anti-scour scales 2 and the tail embedded scales 3, are connected by linking buckles 4; the chain 102 and the outer chain ring are connected by a chain end hoisting ring 5. The anti-scour scales 2 and the tail embedded scales 3 together form a scale armor unit 6 that resembles animal scale armor.

[0039] The inner and outer chain loops 101, 103 of this embodiment are both regular dodecagonal shapes, but may also be other polygonal shapes. The fixed chain mesh 1 of this embodiment is composed of two regular dodecagonal chain loops and chains 102 between their corresponding corner points. The anti-scour scales 2 of this embodiment are steel plate anti-scour scales, specifically three-fold steel plates, including a first front fold, a first middle fold, and a first rear fold. The first front and first rear folds are provided with first holes 201 and second holes 203 on either side, respectively, and the first middle fold has first grooves 202 on either side. The first front folding plate and the first rear folding plate are respectively inserted into the link buckle 4 through the first hole 201 and the second hole 203 to connect, and the first middle folding plate is inserted into the link buckle 4 through the first groove 202 to connect. A plurality of anti-scour scales 2 are respectively connected by the first hole 201 and the second hole 203 to form an anti-scour scale as a whole. A plurality of anti-scour scales 2 are connected to form a trapezoidal structure, which is shaped like an animal scale armor unit 6. The tail embedded scale 3 is connected to the outer chain ring 103. The link buckle 4 is arranged between the adjacent steel plate anti-scour scales 2 and the chain 102 and the edge steel plate anti-scour scales 2, connecting each armor unit 6 and the fixed chain net 1 into a whole. The steel plate anti-scour scale of this embodiment is a Z-shaped three-fold steel plate with a fixed width. The ratio of its horizontal projection length to width can be determined according to the relationship between the number of sides and angle of the fixed chain net polygon.

[0040] The tail embedded scale 3 of this embodiment is an inverted U-shaped three-fold steel plate of equal width, comprising a second front fold, a second middle fold, and a second rear fold. The second front fold and the second rear fold are provided with a third hole 301 and a fourth hole 303, respectively, and the second middle fold is provided with a second groove 302. The end of the anti-scour scale is connected to the third hole 301 of the tail embedded scale 3 via the second hole 203 to form a scale unit 6. The scale unit 6 is an isosceles trapezoid, with its top edge similar in length to the side of the dodecagonal inner chain loop 101 and its bottom edge similar in length to the side of the regular dodecagonal outer chain loop 103. This allows it to be embedded in the sand along with the rear end of the tail embedded scale. Both the anti-scour scale 2 and the tail embedded scale 3 of this embodiment are made of steel, with a thickness of 6-8 mm and a folding angle of 10°-30°.

[0041] The linking buckle 4 of this embodiment is a 304 stainless steel quick-connect ring, which is arranged at the front end of the left and right adjacent steel plate anti-scouring scales 2 and the tail embedded scales 3, connecting the first hole 201 of the anti-scouring scale 2 and the third hole 301 on the tail embedded scale 3 and the second hole 203 of the anti-scouring scale 2. It is arranged at the middle end of the left and right adjacent anti-scouring scales 2 and the tail embedded scale 3, connecting the first groove 202 and the second groove 302, and is used to connect several steel plate anti-scouring scales and tail embedded scales 3 into a scale armor unit 6.

[0042] The inner chain ring 101 and the outer chain ring 103 are both made of steel. A chain end lifting ring 5 is set at the end of the chain 102. The diameter of the inscribed circle of the inner small regular dodecagonal inner chain ring 101 is the cross-sectional diameter of the single pile, and the diameter of the inscribed circle of the outer regular dodecagonal outer chain ring 103 is 3 to 6 times the cross-sectional diameter of the single pile. When the soil conditions around the pile foundation are good, three times the cross-sectional diameter of the single pile can be used, and when the soil conditions are poor, six times the cross-sectional diameter of the single pile can be used.

[0043] The inner chain ring 101 of the inner regular dodecagon is connected to the first hole 201 of the anti-scour scale on the front side of the armor unit 6 through a linking buckle 4, and the outer chain ring 103 is connected to the fourth hole 303 of the embedded scale at the tail of the armor unit 6 through a linking buckle 4. Except for the anti-scour scale on the front side steel plate, the first holes 201 of the anti-scour scales on both sides of the armor unit 6 are provided with linking buckles 4 to connect them with the adjacent chains 102, flexibly connecting the armor unit 6 with the fixed chain net, and through this connection method, the twelve armor units 6 are connected to the fixed chain net to form the offshore wind power single pile foundation scale bionic anti-scour device.

[0044] The present invention also provides a construction method for an offshore wind power monopile foundation scale bionic anti-scour device, comprising the following steps:

[0045] A. Prefabricate inner chain ring 101, chain 102, outer chain ring 103, anti-scour scale 2, tail embedded scale 3, and chain end lifting ring 5 in the factory near the single pile foundation 8. Use the chain end lifting ring 5 to link the chain 102 with the regular dodecagonal outer chain ring 103. One chain 102 that fixes the chain net 1 should be disconnected from the regular dodecagonal inner chain ring 101 and outer chain ring 103 on the adjacent side. Use the link buckle 4 to splice the steel plate anti-scour scale 2 into a scale armor unit and transport it to the shore by means of transportation.

[0046] B. Transport the tower 7 to the installation site by a crane ship or three light floating cranes 9. Connect the armored unit 6 and the fixed chain net 1 on the light floating crane 9 to form a whole. Use the crane ship or three light floating cranes 9 to surround the tower 7 on both sides of the opening of the fixed chain net 1. The bottom of the tower 7 is a single pile foundation 8, and the top of the tower 7 is an offshore wind turbine 11. Figure 9 、 10 shown.

[0047] C. Close the reserved openings to form a complete device. Use a crane ship or three light floating cranes 9 to lift the chain end lifting ring 5 in the device with a sling 10 and slowly release it to the seabed. For existing foundations that have already formed large scour pits, the scour pits should be filled by riprap, sand blankets, etc. before installing the device.

[0048] Working principle: The single pile foundation riprap scale bionic anti-scour structure of the present invention mainly includes four functions: First, the present invention meets the anti-scour effect requirements of the single pile foundation of offshore wind turbines; second, the anti-scour structure of the present invention has an induced sedimentation protection effect, and shows a certain reinforcement effect on the original soil layer; third, the anti-scour structure of the present invention can adapt to irregular terrain and inhibit the development of existing scour pits; fourth, the present invention is light in weight, small in size, easy to deploy, low in transportation cost, and reusable, with the advantages of low manufacturing and operation and maintenance costs.

[0049] In order to meet the first function above, the scales are connected in series to form an anti-scour layer with certain flexibility in the vertical direction and sufficient rigidity in the horizontal direction. This anisotropic stiffness characteristic ensures that the device can adapt to the undulating surface of the seabed and can be firmly adsorbed on the seabed without being affected by ocean currents. Compared with the existing technology, there is no need to set anti-slip rivets, and the anti-scour effect is higher.

[0050] In order to meet the second function above, the unique Z-shaped appearance of the scales can consume the kinetic energy in the water flow and reduce the water flow rate. At the same time, the two grooves set in the middle of the scales increase the water flow path, inducing insoluble matter in the water flow to form accumulation in the grooves. The accumulation covers the scales to enhance the anti-scouring effect of the device.

[0051] In order to meet the third function mentioned above, the steel plate scales of the structure are connected to each other by linking buckles instead of fixed connections, and the scales as a whole are also connected to the fixed chain by linking buckles, so that the structure has a certain deformation and coordination ability like animal scales, and can fit the uneven surface around the covering foundation and existing small scour pits to prevent the scour pits from continuing to expand.

[0052] To meet the fourth requirement, the device is assembled from small scales, allowing for large-scale prefabrication in land-based factories. The buckles and chains utilize established processes, and methods like drilling holes in the scales reduce steel consumption, resulting in a low-cost manufacturing process. Compared to traditional methods like riprap and sandbags, the device is lightweight, compact, easy to deploy, and offers low transportation costs. It is also reusable.

Claims

1. A bionic anti-scour device for offshore wind power monopile foundation, characterized in that: The invention comprises a fixed chain net (1) for being sleeved on the periphery of a monopile foundation, wherein the fixed chain net 1 comprises an inner chain ring (101) and an outer chain ring (103) which are nested with each other, wherein the inner chain ring (101) and the outer chain ring (103) are connected by chains (102), and a plurality of chains (102) are arranged at intervals along the circumference of the inner chain ring (101) and the outer chain ring (103); the area between two adjacent chains (102) constitutes a scale armor unit (6); the scale armor unit (6) comprises several The anti-scour scale (2) and the tail embedded scale (3) are connected by staggering left and right, and connected from the inner chain ring (101) to the outer chain ring (103) to form an anti-scour scale as a whole; the anti-scour scale (2) adjacent to the outer chain ring (103) is connected to the outer chain ring (103) through the tail embedded scale (3); the anti-scour scale (2) and the tail embedded scale (3) together form a scale armor unit (6) shaped like an animal scale armor; the anti-scour scale ( 2) is in a three-fold shape, comprising a first front folding plate, a first middle folding plate and a first rear folding plate; the first front folding plate is provided with a first hole (201) for connecting the anti-scouring scales with the inner chain ring (101) and between the front and rear of the plurality of anti-scouring scales; the first rear folding plate is provided with a second hole (203) for connecting the front and rear of the plurality of anti-scouring scales and between the anti-scouring scales and the tail embedded scale (3); the first middle folding plate is provided with a first groove (204) for connecting the left and right of the plurality of anti-scouring scales 2); the tail embedded scale (3) is an inverted U-shaped three-fold shape, including a second front folding plate, a second middle folding plate and a second rear folding plate; the second front folding plate is provided with a third hole (301) for connecting the anti-scouring scale (2) and the tail embedded scale (3), the second rear folding plate is provided with a fourth hole (303) for connecting the tail embedded scale (3) and the outer chain ring (103), and the second middle folding plate is provided with a second groove (302) for connecting a plurality of tail embedded scales (3) to the left and right.

2. The offshore wind power monopile foundation scale bionic anti-scour device according to claim 1 is characterized in that: The inner chain ring (101) and the anti-scouring scale (2), the adjacent anti-scouring scales (2), the anti-scouring scale (2) and the tail embedded scale (3), the tail embedded scale (3) and the outer chain ring (103), and the chain (102) and the anti-scouring scale (2) located at the edge of the armor unit (6) are respectively connected by connecting buckles (4), so as to connect each armor unit (6) to form a fixed chain net (1).

3. The offshore wind power monopile foundation scale bionic anti-scour device according to claim 1 is characterized in that: The inner chain ring (101) and the outer chain ring (103) are both polygonal; the top edge of the armor unit (6) is similar in length to the side of the inner chain ring (101), and the bottom edge is similar in length to the side of the outer chain ring (103).

4. The offshore wind power monopile foundation scale bionic anti-scour device according to claim 1, characterized in that: The scale armor unit (6) is a trapezoidal structure.

5. The offshore wind power monopile foundation scale bionic anti-scour device according to claim 1 is characterized in that: The inscribed circle diameter of the inner chain ring (101) is the cross-sectional diameter of a single pile, and the inscribed circle diameter of the outer chain ring (103) is 3 to 6 times the cross-sectional diameter of a single pile.

6. The offshore wind power monopile foundation scale bionic anti-scour device according to claim 1, characterized in that: The anti-scouring scales (2) and the tail embedded scales (3) are both made of steel, with a thickness of 6 to 8 mm and a folding angle of 10° to 30°.

7. The offshore wind power monopile foundation scale bionic anti-scour device according to claim 1 is characterized in that: The chain (102) and the outer chain ring (103) are connected via a lifting ring (5).

8. A construction method for the offshore wind power monopile foundation scale bionic anti-scour device according to claim 1, characterized in that: The following steps are involved: (A) Several chains (102) are respectively connected to the outer chain ring (103), and one of the chains (102) should be disconnected from the inner chain ring (101) and the outer chain ring (103) at one end of the adjacent chain to form a reserved opening so as to be installed on the periphery of the single pile foundation; Several anti-scouring scales (2) and tail embedded scales (3) are respectively spliced ​​into scale armor units; and transported to the installation point; (B) linking the armor units (6) to the chains (102) to form a fixed chain net (1), so that the reserved openings of the fixed chain net (1) surround the single pile foundation on both sides; (C) Close the reserved openings to form a complete device, lift the device, and slowly release it to the seabed to complete the installation.

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