Offshore wind turbine split type jacket foundation structure and oblique insertion type grouting connection method

Abstract

The invention discloses an offshore wind turbine split type jacket foundation structure and an oblique insertion type grouting connection method. The offshore wind turbine split type jacket foundation structure comprises a lower jacket, and a suction pile is fixed to the bottom of the lower jacket; a tower drum is mounted at the top of the upper jacket, and the upper jacket and the lower jacket are connected through oblique insertion type grouting; the inserting tip comprises a connecting steel pipe, the top end of the connecting steel pipe extends into the upper jacket, the bottom end of the connecting steel pipe is inserted into the lower jacket, a sealer is arranged at the bottom of the connecting steel pipe, a first grouting cavity is formed between the top of the lower jacket and the sealer, and a second grouting cavity is formed between the bottom of the upper jacket and the top of the connecting steel pipe; the positioning assembly is arranged between the upper jacket and the lower jacket; a fixing assembly is installed on the connecting steel pipe. The jacket is designed into a split type, so that the performance requirements of manufacturing, transportation, hoisting and the like on ship machine equipment are greatly reduced, and the jacket foundation can be conveniently applied to deep and far sea areas.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind power engineering, and in particular to a split-type jacket foundation structure for an offshore wind turbine and an oblique insertion grouting connection method. Background Art

[0002] Offshore wind power, a key pillar of my country's energy transition, has experienced rapid growth in recent years. With the saturation of offshore resource development, offshore wind power is moving further offshore. To reduce costs and increase efficiency, the capacity of individual units is gradually increasing. The jacket foundation structure for offshore wind turbines offers advantages such as high technical maturity and economic efficiency, and continues to have broad application potential in deep waters. However, due to the increasing capacity of individual units, deteriorating environmental conditions, and increasing water depths, the geometric dimensions of wind turbine foundations have increased significantly, and the loads and bending moments they bear have increased significantly. Analysis shows that when water depths exceed 40 meters, jacket transportation and on-site installation place higher demands on the supporting transportation and lifting equipment, significantly increasing costs and even making it difficult for existing marine equipment to meet these requirements. The use of a split jacket structure can reduce the performance requirements for marine equipment and lower project costs.

[0003] In response to the above problems, the utility model CN202321456517.2 proposes a split-type conductor frame structure for offshore wind turbines, including an upper conductor frame and a lower conductor frame. The upper end of the lower conductor frame is vertically provided with a grouting connection section that cooperates with the lower section of the upper conductor frame to achieve connection; the invention patent CN202411457737.6 proposes a split conductor frame foundation in which the main limb pipe of the lower conductor frame is vertically connected to facilitate grouting connection. However, in order to achieve the grouting connection between the upper and lower conductor frames, the above two methods both bend the main limb pipe of the conductor frame, and there is a significant stress concentration problem at the bend. In addition, the verticality of the lower conductor limb of the split structure proposed by the invention patent CN202411457737.6 also limits the size of the root opening, and the overall bending resistance of the structure is reduced, which significantly reduces the economic efficiency of the structure.

[0004] Therefore, deep-sea large-capacity wind turbine foundations urgently need a split-type jacket foundation structure and a corresponding connection method, which has less impact on the stress of the overall structure after installation. Summary of the Invention

[0005] The purpose of the present invention is to provide a split-type jacket foundation structure for an offshore wind turbine and an oblique insertion grouting connection method, so as to solve the problems existing in the prior art.

[0006] To achieve the above-mentioned object, the present invention provides the following solution: The present invention provides a split-type jacket foundation structure for an offshore wind turbine, comprising:

[0007] A lower conductor frame, wherein a suction pile is fixed at the bottom of the lower conductor frame;

[0008] An upper jacket, a tower is installed on the top of the upper jacket, and the upper jacket is installed on the top of the lower jacket;

[0009] The plug tip includes a connecting steel pipe, the top end of the connecting steel pipe extends into the upper jacket, the bottom end of the connecting steel pipe is inserted into the lower jacket, a sealer is provided at the bottom of the connecting steel pipe, a first grouting cavity is formed between the top of the lower jacket and the sealer, a second grouting cavity is formed between the bottom of the upper jacket and the top of the connecting steel pipe, and slurry is poured into the first grouting cavity and the second grouting cavity respectively;

[0010] A positioning assembly, the positioning assembly being disposed between the upper jacket and the lower jacket and used for positioning the connecting steel pipe;

[0011] The first grouting cavity and the second grouting cavity are respectively provided with grouting holes and overflow holes, and a fixing component is installed on the connecting steel pipe.

[0012] According to the offshore wind turbine split jacket foundation structure provided by the present invention, the upper jacket includes a plurality of first supporting main legs, adjacent first supporting main legs are fixed by first diagonal braces, pile platforms are fixed to the top ends of the first supporting main legs, and the tower is fixed to the top surface of the pile platforms.

[0013] According to the offshore wind turbine split jacket foundation structure provided by the present invention, the lower jacket includes a plurality of second support main legs, the first support main legs and the second support main legs are arranged in a one-to-one correspondence, the top end of the connecting steel pipe is inserted into the bottom end of the first support main leg, and the bottom end of the connecting steel pipe is inserted into the top end of the second support main leg. Adjacent second support main legs are fixed by second diagonal braces and horizontal braces, and the bottom end of the second support main leg is fixed to the suction pile.

[0014] Wherein, a grouting hole and an overflow hole are respectively provided on the first supporting main leg and the second supporting main leg.

[0015] According to the offshore wind turbine split jacket foundation structure provided by the present invention, the positioning assembly includes a first ring plate, a second ring plate and a limiting ring plate, the first ring plate is fixed to the bottom of the first supporting main leg, the second ring plate is fixed to the top of the second supporting main leg, the first ring plate and the second ring plate are coaxially abutted, the limiting ring plate is fixed on the outer wall of the connecting steel pipe, and the limiting ring plate abuts against the top surface of the first ring plate.

[0016] According to the offshore wind turbine split jacket foundation structure provided by the present invention, two groups of fixing components are provided, both of which are arranged on the connecting steel pipe and are respectively located in the first grouting cavity and the second grouting cavity, and the fixing components include guide limit blocks, and several groups of guide limit blocks are fixed at equal intervals in the circumferential direction on the outer wall of the connecting steel pipe.

[0017] According to the offshore wind turbine split-type jacket foundation structure provided by the present invention, the sealer includes a sealing ring, and the sealing ring is fixed to the outer wall of the bottom end of the connecting steel pipe.

[0018] According to the offshore wind turbine split-type jacket foundation structure provided by the present invention, a plurality of groups of circumferential shear keys are fixed to the outer wall of the connecting steel pipe and the inner walls of the first supporting main leg (101) and the second supporting main leg (201), and the circumferential shear keys are staggered and arranged at equal intervals along the axis of the connecting steel pipe.

[0019] According to the offshore wind turbine split jacket foundation structure provided by the present invention, a guide device is fixed to the bottom end of the connecting steel pipe, and the guide device is inserted into the second supporting main leg.

[0020] A method for connecting a split-type jacket of an offshore wind turbine by oblique insertion and grouting, comprising the following steps:

[0021] Step 1: Install the lower conductor frame in place;

[0022] Transport the lower jacket with suction piles fixed on the bottom to the designated sea area and securely install it at the preset position on the seabed using the suction piles. Ensure that the connection interface at the top of the lower jacket is level and accurately positioned, laying a foundation for the subsequent installation of the upper jacket and plug tip.

[0023] Step 2: hoist the upper jacket into place;

[0024] Hoist the upper jacket to the top of the lower jacket, and slowly adjust the horizontal position and verticality of the upper jacket so that the connection interface at the bottom of the upper jacket is aligned with the connection interface at the top of the lower jacket. Do not fix it yet, and keep the upper jacket in a suspended state waiting for connection.

[0025] Step 3: Pre-place the tip;

[0026] Place the connecting steel pipe as a whole in the upper jacket in advance, so that its top and bottom ends initially extend into the connection interface at the bottom of the upper jacket. Use the positioning assembly to initially limit the connecting steel pipe to prevent the connecting steel pipe from shifting during the lifting process. Use the guide device to ensure that the axis of the connecting steel pipe is consistent with the axis of the connection interface of the upper and lower jackets; Step 4: Move the connecting steel pipe down into place;

[0027] After the upper and lower jackets are docked, the connecting steel pipe is slowly moved downward through the guide device until half of the connecting steel pipe is inserted into the lower jacket, and the first ring plate abuts against the limiting ring plate; at this time, the sealer at the bottom of the connecting steel pipe fits with the lower jacket to form a sealed state, and then a first grouting cavity is formed between the top of the lower jacket and the sealer; at the same time, a second grouting cavity is formed between the bottom of the upper jacket and the top of the connecting steel pipe, and the positioning assembly further fixes the position of the connecting steel pipe; step five, check the sealing of the grouting cavity and the channel;

[0028] Check the sealing of the first and second grouting chambers, and confirm that there is no leakage at the bottom of the first grouting chamber through the sealer; check whether the grouting holes and overflow holes on the two grouting chambers are unobstructed, and ensure that the grouting channels and exhaust channels are not blocked, so as to prepare for subsequent grouting operations;

[0029] Step six, grouting the first grouting cavity;

[0030] Inject slurry into the first grouting cavity through the grouting hole of the first grouting cavity, and observe the corresponding overflow hole during the grouting process. When the overflow hole has continuous and uniform slurry flowing out, it indicates that the first grouting cavity is full of slurry. Close the grouting hole and the overflow hole to complete the grouting operation of the first grouting cavity;

[0031] Step seven, grouting the second grouting cavity;

[0032] After the slurry in the first grouting cavity has initially solidified, inject slurry into the cavity through the grouting hole of the second grouting cavity. Similarly, observe its overflow hole. When qualified slurry flows out of the overflow hole, close the corresponding grouting hole and overflow hole to complete the grouting operation of the second grouting cavity.

[0033] Step 8: slurry curing;

[0034] The slurry in the first grouting cavity and the second grouting cavity is cured, and the curing environment is controlled according to the slurry characteristics to ensure that the slurry reaches the designed strength, so that the connecting steel pipe is firmly connected to the upper and lower jackets through the slurry.

[0035] The present invention discloses the following technical effects:

[0036] 1) The present invention adopts a split design, which allows large structures to be disassembled for transportation, reducing the size and weight restrictions for sea transportation, and reducing transportation difficulty and cost; at the same time, the split installation can simplify the offshore lifting process, adapt to complex offshore operating environments, and improve installation efficiency.

[0037] 2) The plug tip is connected through a connecting steel pipe with a double grouting cavity. The grouting holes and overflow holes ensure that the slurry fills the cavity without voids. After the slurry solidifies, it forms an integral force-bearing structure with the connecting steel pipe. The connection does not bend, and the force is transmitted directly, so that the upper and lower jackets are tightly connected and the force is evenly distributed. The fixing assembly further strengthens the stability of the connecting steel pipe, avoids loosening, and improves the overall structure's ability to resist wind and waves and overturning.

[0038] 3) The sealer connected to the bottom of the steel pipe is combined with the sealing function of the positioning component, and the slurry sealing of the double grouting chamber can effectively prevent seawater from invading the internal structure of the foundation and reduce the damage to the components caused by seawater corrosion. At the same time, the grouting material itself has a certain degree of corrosion resistance, further extending the service life of the foundation.

[0039] 4) The positioning assembly can accurately guide the guide tip into position, reducing alignment errors during offshore installation and improving installation accuracy; the suction piles at the bottom of the lower jacket can provide reliable vertical and horizontal constraints, enhancing the overall pull-out and anti-slip capabilities of the foundation, ensuring structural stability in complex marine environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0041] Figure 1 This is an overall schematic diagram of the fan support structure of the present invention;

[0042] Figure 2 Schematic diagram of the upper jacket and wind turbine tower of the present invention;

[0043] Figure 3 A schematic diagram of the lower conductor frame and suction piles of the present invention;

[0044] Figure 4 It is a schematic diagram of the oblique insertion grouting connection section of the present invention.

[0045] Among them, 1. Upper conductor frame; 101. First supporting main leg; 102. Pile base; 103. First diagonal brace; 2. Lower conductor frame; 201. Second supporting main leg; 202. Horizontal brace; 203. Second diagonal brace; 301. First grouting cavity; 302. Second grouting cavity; 303. First ring plate; 304. Second ring plate; 305. Limiting ring plate; 306. Guide limiting block; 307. Seal; 308. Grouting hole; 309. Overflow hole; 310. Guide device; 311. Connecting steel pipe; 312. Circumferential shear key; 4. Insert tip; 5. Tower; 6. Suction pile. DETAILED DESCRIPTION

[0046] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0047] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] Reference Figure 1-4 The present invention provides a split-type jacket foundation structure for an offshore wind turbine, comprising:

[0049] A lower jacket frame 2, with a suction pile 6 fixed to the bottom of the lower jacket frame 2;

[0050] An upper jacket 1, a tower 5 is installed on the top of the upper jacket 1, and the upper jacket 1 is installed on the top of the lower jacket 2;

[0051] The plug tip 4 includes a connecting steel pipe 311. The top end of the connecting steel pipe 311 extends into the upper jacket 1, and the bottom end of the connecting steel pipe 311 is inserted into the lower jacket 2. A sealer 307 is provided at the bottom of the connecting steel pipe 311. A first grouting cavity 301 is formed between the top of the lower jacket 2 and the sealer 307. A second grouting cavity 302 is formed between the bottom of the upper jacket 1 and the top of the connecting steel pipe 311. Slurry is poured into the first grouting cavity 301 and the second grouting cavity 302 respectively.

[0052] A positioning assembly is provided between the upper jacket 1 and the lower jacket 2 and is used to position the connecting steel pipe 311;

[0053] The first grouting cavity 301 and the second grouting cavity 302 are respectively provided with a grouting hole 308 and an overflow hole 309 , and a fixing component is installed on the connecting steel pipe 311 .

[0054] To further optimize the solution, the upper jacket 1 includes several first supporting main legs 101 , adjacent first supporting main legs 101 are fixed by first diagonal braces 103 , pile platforms 102 are fixed to the top of the first supporting main legs 101 , and the tower 5 is fixed on the top surface of the pile platforms 102 .

[0055] The upper jacket 1 utilizes a modular truss design, consisting of several first support legs 101, first diagonal braces 103, and a top pile pedestal 102. Adjacent first support legs 101 form a spatially stable structure through the cross-arranged first diagonal braces 103, effectively dispersing the horizontal and vertical loads transmitted by the tower 5. Pile pedestals 102 are welded to the tops of the first support legs 101, providing a flat and stable mounting surface for the tower 5. Their bottoms are pre-set with through-holes for connecting steel pipes 311, and the inner walls are provided with grouting holes 308 and overflow holes 309 (low-level grouting, high-level overflow layout). This design enhances overall rigidity through the truss-type support system, reducing stress concentration on a single leg. Standardized interfaces and grouting channels facilitate subsequent docking of the upper and lower jackets 2 and dual-chamber grouting construction, ensuring an efficient transmission path for the tower 5 load from the pile pedestal 102 to the first support leg 101 to the connecting steel pipe 311.

[0056] Further optimized, the lower jacket 2 includes a plurality of second supporting main legs 201, the first supporting main legs 101 and the second supporting main legs 201 are arranged in a one-to-one correspondence, the top of the connecting steel pipe 311 is inserted into the bottom of the first supporting main leg 101, and the bottom of the connecting steel pipe 311 is inserted into the top of the second supporting main leg 201, and adjacent second supporting main legs 201 are fixed by second diagonal braces 203 and horizontal braces 202, and the bottom of the second supporting main legs 201 is fixed on the suction pile 6;

[0057] The first supporting main leg 101 and the second supporting main leg 201 are respectively provided with a grouting hole 308 and an overflow hole 309 .

[0058] The lower jacket 2 is based on the second support leg 201 as its core load-bearing component, corresponding one-to-one with the first support leg 101 of the upper jacket 1. Suction piles 6 are fixed at the bottom to embed into the seabed soil. Adjacent second support legs 201 form a rigid frame with second diagonal braces 203 and horizontal braces 202, enhancing its ability to withstand horizontal loads. The top of each second support leg 201 features an insertable interface for connecting steel pipes 311. Grouting holes 308 and overflow holes 309 are reserved on the inner wall. The bottom is flange-connected to suction piles 6, enhancing the foundation's pullout and anti-slip performance through multi-directional constraints. This solution, through the combined design of "support legs + spatial braces + suction piles 6," ensures stable anchoring of the lower jacket 2 in complex seabed environments. The corresponding interface design with the upper jacket 1 ensures coaxial docking accuracy, laying the foundation for dual grouting chamber construction.

[0059] A further optimized solution is provided, in which the positioning assembly includes a first ring plate 303, a second ring plate 304 and a limiting ring plate 305. The first ring plate 303 is fixed to the bottom of the first supporting main leg 101, and the second ring plate 304 is fixed to the top of the second supporting main leg 201. The first ring plate 303 and the second ring plate 304 are coaxially abutted, and the limiting ring plate 305 is fixed on the outer wall of the connecting steel pipe 311, and the limiting ring plate 305 abuts against the top surface of the first ring plate 303.

[0060] The positioning assembly consists of a coaxially arranged first ring plate 303 (bottom of the upper conductor frame 1), a second ring plate 304 (top of the lower conductor frame 2) and a limiting ring plate 305 connected to the outer wall of the steel pipe 311. The edges of the first ring plate 303 and the second ring plate 304 are provided with 3-4 groups of radial tenons and grooves. When docking, the convex and concave tenons and grooves are used to achieve coaxial positioning and tangential constraints. The bottom surface of the limiting ring plate 305 abuts against the top surface of the first ring plate 303 to limit the vertical displacement of the connecting steel pipe 311. The contact surface of the ring plate is coated with anti-corrosion sealant, and the built-in pressure sensor of the limiting ring plate 305 monitors the contact pressure in real time to ensure that the upper and lower ring plates are fully fitted. This assembly combines mechanical positioning with sensor monitoring to control the docking accuracy within ±2mm, which not only provides stable support for temporary fixation before grouting, but also prevents seawater from penetrating the connection interface, thereby improving the durability of the node.

[0061] A further optimized solution is provided with two groups of fixing components, both of which are arranged on the connecting steel pipe 311 and are respectively located in the first grouting cavity 301 and the second grouting cavity 302. The fixing components include guide limit blocks 306, and several groups of guide limit blocks 306 are fixed on the outer wall of the connecting steel pipe 311 at equal intervals in the circumferential direction.

[0062] The fixing assembly consists of two sets of circumferentially evenly spaced guide stoppers 306, located within the first grouting cavity 301 and the second grouting cavity 302, respectively, and welded to the outer wall of the connecting steel pipe 311. The stoppers feature a trapezoidal cross-section, wider at the top and narrower at the bottom. This design, through multi-point mechanical stoppers, prevents the connecting steel pipe 311 from becoming excessively eccentric within the jacket leg. Combined with the guiding action of the guide device 310, this allows for rapid and precise docking of the upper and lower jackets 2.

[0063] According to a further optimized solution, the sealer 307 includes a sealing ring, which is fixed on the outer wall of the bottom end of the connecting steel pipe 311.

[0064] The core component of sealer 307 is a multi-layer composite sealing ring connected to the outer wall of the bottom end of steel pipe 311. Its inner layer is made of highly elastic nitrile rubber, and its outer layer is coated with a polytetrafluoroethylene corrosion-resistant layer. The lip is designed with a 45° bevel and contains a built-in annular compression spring. When connecting steel pipe 311 is inserted into the second support leg 201 of the lower conductor frame 2, the sealing ring is squeezed and elastically deformed, forming a dynamic seal against the inner wall of the support leg. The spring compensates for material aging and deformation caused by long-term service. This sealing structure, combined with the slurry seal of the dual grouting chambers, forms a double barrier, effectively preventing seawater from intruding into the first grouting chamber 301. Combined with the anti-corrosion coating at the annular plate interface, this creates a multi-dimensional corrosion protection system, significantly extending the service life of the foundation structure.

[0065] According to a further optimized solution, a plurality of groups of annular shear keys 312 are fixed to the outer wall of the connecting steel pipe 311 and the inner walls of the first supporting main leg (101) and the second supporting main leg (201), and the annular shear keys 312 are staggered and arranged at equal intervals along the axis of the connecting steel pipe 311.

[0066] The circumferential shear keys 312 are isosceles right-angled triangle protrusions (height 25-30mm, spacing 200-300mm) arranged at equal intervals along the axis of the connecting steel pipe 311, forming a spiral shear interface. During the grouting process, the shear keys are embedded in high-strength grouting material (24h compressive strength ≥50MPa). After solidification, they form a tooth-like interlocking structure with the grout, efficiently transmitting the shear load borne by the connecting steel pipe 311 to the upper and lower supporting main legs through the key teeth. This design breaks through the limitations of traditional planar bonding and greatly improves the interface shear bearing capacity through spatial geometric interlocking. Verified by finite element analysis, it can increase the shear strength of the node by more than 40%, effectively coping with the frequent alternating loads borne by offshore wind turbines.

[0067] To further optimize the solution, a guide device 310 is fixed to the bottom end of the connecting steel pipe 311 , and the guide device 310 is inserted into the second supporting main leg 201 .

[0068] The guide device 310 connected to the bottom end of the steel pipe 311 adopts a frustum-shaped design (cone angle 20°) with a spiral guide groove (pitch 100mm) on the surface. When inserted into the second supporting main leg 201 of the lower conductor frame 2, the radial deviation within ±5mm can be automatically corrected through the sliding fit of the conical guide and the spiral groove, reducing the difficulty of offshore lifting and alignment. The length of the guide device 310 is 1 / 3 of the diameter of the supporting main leg pipe, and the end is hardened (hardness HRC50-55) to ensure that it penetrates the possible marine biological attachment layer or slight sediment during insertion, achieving fast and accurate positioning. This structure works in conjunction with the positioning ring plate and the guide limit block 306 to form a three-level docking system of "tip guide → ring plate positioning → limit block fixation", which significantly improves offshore construction efficiency and installation accuracy.

[0069] A method for connecting a split-type jacket of an offshore wind turbine by oblique insertion and grouting, comprising the following steps:

[0070] Step 1: Install the lower conductor frame 2 in place;

[0071] Transport the lower jacket 2 with suction piles 6 fixed at the bottom to the designated sea area, and firmly install the lower jacket 2 at a preset position on the seabed using the suction piles 6, ensuring that the connection interface at the top of the lower jacket 2 is horizontal and accurately positioned, thus providing a foundation for the subsequent installation of the upper jacket 1 and the plug tip 4;

[0072] Step 2: hoist the upper jacket 1 into place;

[0073] Hoist the upper jacket 1 to the top of the lower jacket 2, and slowly adjust the horizontal position and verticality of the upper jacket 1 so that the connection interface at the bottom of the upper jacket 1 is aligned with the connection interface at the top of the lower jacket 2. Do not fix it yet, and keep the upper jacket 1 in a suspended state waiting for connection;

[0074] Step 3: Pre-place the tip 4;

[0075] Place the connecting steel pipe 311 in the upper jacket 1 in advance, so that its bottom end initially extends into the connection interface at the bottom of the upper jacket 1. Use the guide device 310 to ensure that the axis of the connecting steel pipe 311 is consistent with the axis of the connection interface of the upper and lower jackets 2.

[0076] Step 4: Move the connecting steel pipe 311 downward into place;

[0077] After the upper jacket 1 and the lower jacket 2 are docked, the connecting steel pipe 311 is slowly moved downward through the guide device 310 until half of the connecting steel pipe 311 extends into the interior of the lower jacket 2, and the first ring plate 303 abuts against the limiting ring plate 305; at this time, the sealer 307 at the bottom of the connecting steel pipe 311 fits with the lower jacket 2 to form a sealed state, and then a first grouting cavity 301 is formed between the top of the lower jacket 2 and the sealer 307; at the same time, a second grouting cavity 302 is formed between the bottom of the upper jacket 1 and the top of the connecting steel pipe 311, and the positioning assembly further fixes the position of the connecting steel pipe 311;

[0078] Step 5: Check the sealing of the grouting cavity and the hole;

[0079] Check the sealing of the first grouting chamber 301 and the second grouting chamber 302. Use the sealer 307 to confirm that there is no leakage at the bottom of the first grouting chamber 301. Check whether the grouting holes 308 and overflow holes 309 on the two grouting chambers are unobstructed. Ensure that the grouting channel and the exhaust channel are not blocked, and prepare for the subsequent grouting operation.

[0080] Step six, grouting the first grouting cavity 301;

[0081] Inject slurry into the first grouting cavity 301 through the grouting hole 308. During the grouting process, observe the corresponding overflow hole 309. When the overflow hole 309 has continuous and uniform slurry flowing out, it indicates that the first grouting cavity 301 is full of slurry. Close the grouting hole 308 and the overflow hole 309 to complete the grouting operation of the first grouting cavity 301.

[0082] Step seven, grouting the second grouting cavity 302;

[0083] After the slurry in the first grouting cavity 301 has initially solidified, slurry is injected into the cavity through the grouting hole 308 of the second grouting cavity 302. Similarly, its overflow hole 309 is observed. When qualified slurry flows out of the overflow hole 309, the corresponding grouting hole 308 and overflow hole 309 are closed to complete the grouting operation of the second grouting cavity 302.

[0084] Step 8: slurry curing;

[0085] The slurry in the first grouting cavity 301 and the second grouting cavity 302 is cured, and the curing environment is controlled according to the slurry characteristics to ensure that the slurry reaches the designed strength, so that the connecting steel pipe 311 is firmly connected to the upper and lower jackets 1 and 2 through the slurry.

[0086] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0087] The embodiments described above are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by persons skilled in the art should fall within the scope of protection defined by the claims of the present invention.

Claims

1. A split-type jacket foundation structure for an offshore wind turbine, characterized in that: include: A lower conductor frame (2), wherein a suction pile (6) is fixed at the bottom of the lower conductor frame (2); an upper conductor frame (1), wherein a tower (5) is installed at the top of the upper conductor frame (1), and the upper conductor frame (1) and the lower conductor frame (2) are connected by oblique insertion grouting; An insert tip (4), the insert tip (4) comprising a connecting steel pipe (311), the top end of the connecting steel pipe (311) extending into the upper conductor frame (1), the bottom end of the connecting steel pipe (311) inserted into the lower conductor frame (2), a sealer (307) provided at the bottom of the connecting steel pipe (311), a first grouting cavity (301) formed between the top of the lower conductor frame (2) and the sealer (307), a second grouting cavity (302) formed between the bottom of the upper conductor frame (1) and the top of the connecting steel pipe (311), slurry being poured into the first grouting cavity (301) and the second grouting cavity (302), respectively; A positioning assembly, the positioning assembly being arranged between the upper conductor frame (1) and the lower conductor frame (2) and being used for positioning the connecting steel pipe (311); The first grouting cavity (301) and the second grouting cavity (302) are respectively provided with a grouting hole (308) and an overflow hole (309), and a fixing component is installed on the connecting steel pipe (311).

2. The offshore wind turbine split-type jacket foundation structure according to claim 1, characterized in that: The upper jacket (1) comprises a plurality of first supporting main legs (101), adjacent first supporting main legs (101) are fixed by first diagonal braces (103), a pile base (102) is fixed at the top end of each first supporting main leg (101), and the tower (5) is fixed on the top surface of the pile base (102).

3. The offshore wind turbine split-type jacket foundation structure according to claim 2, characterized in that: The lower conductor frame (2) includes a plurality of second supporting main legs (201), the first supporting main legs (101) and the second supporting main legs (201) are arranged in a one-to-one correspondence, the top end of the connecting steel pipe (311) is inserted into the bottom end of the first supporting main leg (101), the bottom end of the connecting steel pipe (311) is inserted into the top end of the second supporting main leg (201), adjacent second supporting main legs (201) are fixed by second diagonal braces (203) and horizontal braces (202), and the bottom end of the second supporting main legs (201) is fixed on the suction pile (6); The first supporting main leg (101) and the second supporting main leg (201) are respectively provided with a grouting hole (308) and an overflow hole (309).

4. The offshore wind turbine split-type jacket foundation structure according to claim 3, characterized in that: The positioning assembly comprises a first ring plate (303), a second ring plate (304) and a limiting ring plate (305); the first ring plate (303) is fixed to the bottom of the first supporting main leg (101); the second ring plate (304) is fixed to the top of the second supporting main leg (201); the first ring plate (303) and the second ring plate (304) are coaxially abutted; the limiting ring plate (305) is fixed to the outer wall of the connecting steel pipe (311); and the limiting ring plate (305) abuts against the top surface of the first ring plate (303).

5. The offshore wind turbine split-type jacket foundation structure according to claim 3, characterized in that: Two groups of the fixing components are provided, both of which are provided on the connecting steel pipe (311) and are located in the first grouting cavity (301) and the second grouting cavity (302), respectively. The fixing components include guide limit blocks (306), and a plurality of guide limit blocks (306) are fixed on the outer wall of the connecting steel pipe (311) at equal intervals in the circumferential direction.

6. The offshore wind turbine split-type jacket foundation structure according to claim 1, characterized in that: The sealer (307) includes a sealing ring, which is fixed on the outer wall of the bottom end of the connecting steel pipe (311).

7. The offshore wind turbine split jacket foundation structure according to claim 1, characterized in that: A plurality of groups of circumferential shear keys (312) are fixed to the outer wall of the connecting steel pipe (311) and the inner walls of the first supporting main leg (101) and the second supporting main leg (201). The circumferential shear keys (312) are staggered and arranged at equal intervals along the axis of the connecting steel pipe (311).

8. The offshore wind turbine split-type jacket foundation structure according to claim 3, characterized in that: A guide device (310) is fixed to the bottom end of the connecting steel pipe (311), and the guide device (310) is inserted into the second supporting main leg (201).

9. A method for connecting an offshore wind turbine split jacket by oblique insertion grouting, based on the offshore wind turbine split jacket foundation structure according to any one of claims 1 to 8, characterized in that: The steps include: Step 1: Install the lower conductor frame (2) in place; The lower jacket (2) with suction piles (6) fixed at the bottom is transported to a designated sea area, and the lower jacket (2) is firmly installed at a preset position on the seabed through the suction piles (6), ensuring that the connection interface at the top of the lower jacket (2) is horizontal and accurately positioned, thereby providing a foundation for the subsequent installation of the upper jacket (1) and the plug tip (4); Step 2: hoisting the upper jacket (1) into place; Hoist the upper jacket (1) to the top of the lower jacket (2), slowly adjust the horizontal position and verticality of the upper jacket (1) so that the connection interface at the bottom of the upper jacket (1) is aligned with the connection interface at the top of the lower jacket (2), and do not fix it temporarily, keeping the upper jacket (1) in a suspended state waiting for connection; Step 3: Pre-place the tip (4); The connecting steel pipe (311) is pre-placed in the upper jacket (1) so that its bottom end initially extends into the connecting interface at the bottom of the upper jacket (1), and the guide device (310) is used to ensure that the axis of the connecting steel pipe (311) is consistent with the axis of the connecting interface of the upper and lower jackets (2); Step 4: The connecting steel pipe (311) is moved downward into place; After the upper conductor frame (1) and the lower conductor frame (2) are docked, the connecting steel pipe (311) is slowly moved downward through the guide device (310) until half of the connecting steel pipe (311) is inserted into the interior of the lower conductor frame (2), and the first ring plate (303) is in contact with the limiting ring plate (305); at this time, the sealer (307) at the bottom of the connecting steel pipe (311) is fitted with the lower conductor frame (2) to form a sealed state, thereby forming a first grouting cavity (301) between the top of the lower conductor frame (2) and the sealer (307); at the same time, a second grouting cavity (302) is formed between the bottom of the upper conductor frame (1) and the top of the connecting steel pipe (311), and the positioning assembly further fixes the position of the connecting steel pipe (311); Step 5: Check the sealing of the grouting cavity and the hole; Check the sealing of the first grouting chamber (301) and the second grouting chamber (302), and confirm that there is no leakage at the bottom of the first grouting chamber (301) through the sealer (307); check whether the grouting holes (308) and the overflow holes (309) on the two grouting chambers are unobstructed, and ensure that the grouting channel and the exhaust channel are not blocked, so as to prepare for the subsequent grouting operation; Step six, grouting the first grouting cavity (301); Inject slurry into the first grouting cavity (301) through the grouting hole (308), observe the corresponding overflow hole (309) during the grouting process, and when the overflow hole (309) has continuous and uniform slurry flowing out, it indicates that the first grouting cavity (301) is full of slurry, close the grouting hole (308) and the overflow hole (309), and complete the grouting operation of the first grouting cavity (301); Step seven, grouting the second grouting cavity (302); After the slurry in the first grouting cavity (301) is initially solidified, slurry is injected into the cavity through the grouting hole (308) of the second grouting cavity (302), and the overflow hole (309) is also observed. When qualified slurry flows out of the overflow hole (309), the corresponding grouting hole (308) and the overflow hole (309) are closed to complete the grouting operation of the second grouting cavity (302); Step 8: slurry curing; The slurry in the first grouting cavity (301) and the second grouting cavity (302) is cured, and the curing environment is controlled according to the slurry characteristics to ensure that the slurry reaches the designed strength, so that the connecting steel pipe (311) and the upper and lower jackets (1 and 2) are firmly connected through the slurry.

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