Fabricated ecc-steel combined offshore wind floating foundation

Abstract

The utility model provides a kind of assembly type ECC-steel combined offshore wind power floating foundation, including first combination part and second combination part, first combination part includes first steel pipe, ECC shell, first annular rib plate, second steel pipe, multiple connecting plates;First steel pipe, second steel pipe, first annular rib plate and connecting plate form first pouring cavity of pouring ordinary concrete between them;Second pouring cavity of pouring UHPC concrete is formed between first steel pipe and connecting plate;Second combination part includes reinforcing cage, pipe fitting;Longitudinal reinforcement connecting portion;After formwork is carried out to reinforcing cage, third pouring cavity of pouring ECC material is formed between pipe fitting. The offshore wind power floating foundation has excellent stress performance and shock absorption and energy dissipation performance, significantly enhances the integrity of the connection, while the structure is simple, convenient to transport and construct, can reliably realize the connection of variable cross-section combined foundation and composite buoy, and is convenient for later maintenance and repair.

Description

Technical Field

[0001] This utility model relates to the technical field of offshore wind turbine floating foundations, and more specifically, to a prefabricated ECC-steel composite offshore wind turbine floating foundation. Background Technology

[0002] As offshore wind power expands into deeper waters, floating foundations have become a major technological direction. Floating foundations are the core supporting the entire wind turbine structure, and their performance directly affects the structure's safety and economic efficiency.

[0003] Traditional cast-in-place concrete floating foundations face challenges such as high construction difficulty at sea, difficulty in quality control, and long construction cycles. Precast floating foundations, on the other hand, present challenges in transportation and high requirements for wharf facilities. Furthermore, the connection nodes between the upper wind turbine foundation and the floating pontoons must withstand complex cyclic loads from wind, waves, and currents. Traditional rigid connection nodes are prone to plastic damage and excessive residual deformation under extreme loads, leading to difficult structural repairs, high maintenance costs, and even overall instability.

[0004] While there are some solutions in the existing technology to improve node performance, such as using partial prestressing or pure steel structures, there are still problems such as insufficient energy dissipation capacity, large residual deformation, and poor durability in marine corrosive environments. Utility Model Content

[0005] In view of this, the purpose of this utility model is to provide a prefabricated ECC-steel composite offshore wind turbine floating foundation to solve the above problems.

[0006] The present invention adopts the following solution: This application provides a prefabricated ECC-steel composite offshore wind turbine floating foundation, including a first assembly and a second assembly connected below the first assembly, wherein... The first assembly includes a first steel pipe, an ECC shell cast outside the first steel pipe, a first annular rib connected inside the first steel pipe, a second steel pipe disposed at the center of the first steel pipe, and a plurality of connecting plates surrounding and connected to the lower end face of the first annular rib; a first pouring cavity for casting ordinary concrete is formed between the first steel pipe, the second steel pipe, the first annular rib, and the connecting plates; a second pouring cavity for casting UHPC concrete is formed between the first steel pipe and the connecting plates. The second assembly includes a reinforcing cage, and a pipe fitting disposed within the reinforcing cage to form a cavity; the upper end of the reinforcing cage is provided with a longitudinal reinforcement connecting part, which is arranged to form a shape adapted to the inner cavity of the first steel pipe and is inserted into the second casting cavity; after the reinforcing cage is supported by formwork, a third casting cavity is formed between it and the pipe fitting, and the third casting cavity is filled with ECC material.

[0007] Furthermore, the connecting plate is a corrugated plate.

[0008] Furthermore, the first steel pipe is a square steel pipe formed by welding four steel plates; the second steel pipe is a round steel pipe.

[0009] Furthermore, it also includes vertical ribs connected to the inner wall of the first steel pipe and the upper surface of the first annular rib; a second annular rib is also provided on the inner wall of the second steel pipe.

[0010] Furthermore, a grouting hole is provided on the side wall of the first steel pipe below the first annular rib.

[0011] Furthermore, shear studs are provided on the inner wall of the first steel pipe.

[0012] Furthermore, before casting the ECC shell, the outer surface of the first steel pipe needs to be coated with epoxy resin and treated with sand.

[0013] Furthermore, before pouring concrete into the first pouring cavity, the outer peripheral wall of the second steel pipe placed inside the first steel pipe needs to be coated with epoxy resin and sand is applied.

[0014] Furthermore, the longitudinal bars at the upper end of the steel cage, and the multiple SMA lap bars arranged between the longitudinal bars are bent to form the longitudinal bar connection part.

[0015] Furthermore, the pipe fitting is made of PVC pipe, and a sealed cavity is formed inside the PVC pipe after the ECC material is poured in the third casting cavity.

[0016] By adopting the above technical solution, the present invention can achieve the following technical effects: The prefabricated ECC-steel composite offshore wind turbine floating foundation of this application possesses excellent load-bearing and vibration damping performance, significantly enhancing the overall integrity of the connection. Simultaneously, the structure is simple to construct, convenient for transportation and construction, reliably connects the variable cross-section composite foundation to the composite pontoon, and facilitates subsequent maintenance and repair. Furthermore, it significantly improves the applicability of this type of connection in prefabricated buildings, particularly in harsh marine environments, and has broad application prospects in the field of prefabricated offshore wind turbine structures. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the first assembly structure of a prefabricated ECC-steel composite offshore wind power floating foundation according to an embodiment of this utility model; Figure 2 This is a bottom view of the first assembly section of a prefabricated ECC-steel composite offshore wind turbine floating foundation according to an embodiment of this utility model. Figure 3 This is a schematic diagram of the steel cage structure of the second assembly part of a prefabricated ECC-steel composite offshore wind power floating foundation according to an embodiment of this utility model; Figure 4 This is a structural schematic diagram of the second assembly part of a prefabricated ECC-steel composite offshore wind turbine floating foundation according to an embodiment of this utility model; Figure 5 This is a schematic diagram and enlarged view of a prefabricated ECC-steel composite offshore wind turbine floating foundation according to an embodiment of this utility model; Figure 6 This is a schematic diagram of the structure of a prefabricated ECC-steel composite offshore wind turbine floating foundation after the wind turbine tower is installed, according to an embodiment of this utility model. Icons: First assembly 1, Second assembly 2, UHPC concrete 3, ECC shell 101, Steel plate 102, Second steel pipe 103, First annular rib 104, Vertical rib 105, Second annular rib 106, Connecting plate 107, Stud 108, Epoxy resin adhesive 109, Ordinary concrete 110, Grouting hole 111, Second casting cavity 112, Longitudinal reinforcement 202, SMA lap splice 203, Stirrup 204, Pipe fitting 205, ECC material 201. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0020] Example Combination Figures 1 to 6As shown, this embodiment provides a prefabricated ECC-steel composite offshore wind turbine floating foundation, including a first assembly 1 and a second assembly 2 connected below the first assembly 1, wherein... Specifically, in this embodiment, such as Figure 1 and Figure 2 and Figure 5 As shown, the first assembly 1 includes a first steel pipe welded into a square shape by four steel plates 102, an ECC shell 101 cast outside the first steel pipe, a first annular rib plate 104 in the shape of a U-shape connected inside the first steel pipe, a second steel pipe 103 cylindrically disposed at the center of the first steel pipe, and four connecting plates 107 surrounding and connected to the lower end face of the first annular rib plate 104, wherein the connecting plates 107 are corrugated; a first pouring cavity for casting ordinary concrete 110 is formed between the first steel pipe, the second steel pipe 103, the first annular rib plate 104 and the connecting plates 107; a second pouring cavity 112 for casting UHPC concrete 3 is formed between the first steel pipe and the connecting plates 107. like Figure 3 and Figure 4 As shown, the second assembly 2 includes a cylindrical steel cage and a PVC pipe 205 disposed within the steel cage to form a cavity. The upper end of the steel cage is provided with a longitudinal reinforcement 202 connection. Specifically, multiple longitudinal reinforcements 202 at the upper end of the steel cage, and multiple SMA lap reinforcements 203 disposed between the longitudinal reinforcements 202, are bent to form the longitudinal reinforcement 202 connection. This connection is formed to fit the inner cavity of the first steel pipe and is inserted into the second pouring cavity 112. A grouting hole 111 is provided on the side wall of the first steel pipe below the first annular rib 104 for pouring concrete into the second pouring cavity 112. After the steel cage is supported by formwork, a third pouring cavity is formed between it and the pipe 205. ECC material 201 is poured into the third pouring cavity, and after the ECC material 201 is poured into the third pouring cavity, a sealed cavity is formed inside the PVC pipe. The second steel pipe 103 is used to install the upper structure such as the wind turbine tower.

[0021] The offshore wind power floating foundation of this application has a connection structure that can effectively ensure the load transfer between the structure of the variable cross-section outer ECC shell 101-first square tube-concrete-second steel pipe 103 and the composite steel bar-ECC material 201 combined pontoon, exhibiting excellent stress performance and vibration reduction and energy dissipation performance, and significantly enhancing the integrity of the connection.

[0022] Among them, ECC material 201 can dissipate a large amount of energy through its multi-crack characteristic; while UHPC ensures high strength and integrity of the connection area, effectively limiting damage to a controllable and small range. Meanwhile, ECC material 201 not only has a low density, effectively reducing structural weight, but also provides excellent corrosion protection for the internal steel plate 102, improving durability. PVC pipes form cavities as permanent formwork, further reducing the structural weight while lowering the overall average density. SMA lap joints 203 are used in the core area of ​​the connection as energy dissipation and reset elements. Utilizing their stable hyperelastic properties, they can efficiently dissipate externally input energy and provide strong restoring force, thereby significantly reducing permanent deformation after extreme loads.

[0023] Furthermore, it also includes a vertical rib 105, which is connected to the inner wall of the first steel pipe and the upper end face of the first annular rib 104; a second annular rib 106 is also provided on the inner wall of the second steel pipe 103 to strengthen the first steel pipe and the second steel pipe 103. Shear studs 108 are provided on the inner wall of the first steel pipe.

[0024] Furthermore, in this embodiment, before pouring the ECC shell 101, epoxy resin adhesive 109 needs to be applied to the outer surface of the first steel pipe and sand-planted. Before pouring concrete into the first pouring cavity, epoxy resin adhesive 109 needs to be applied to the outer peripheral wall of the second steel pipe 103 placed inside the first steel pipe and sand-planted. The sand-planting refers to spraying quartz sand onto the uncured epoxy resin adhesive layer, which forms a solid rough surface layer after curing. This provides significant friction and mechanical interlocking force to the interface between the ECC material 201 and the steel pipe, ensuring effective load transfer between complex interfaces. At the same time, the encapsulation of the ECC shell can effectively block moisture and corrosive ions, preventing corrosion of the internal steel.

[0025] The following is a detailed description of the construction of this prefabricated ECC-steel composite offshore wind turbine floating foundation: First, the first assembly 1 and the second assembly are prefabricated at the prefabrication plant; The prefabrication of the first assembly 1 includes the following steps: First, the second annular rib 106 is welded to the inner wall of the second steel pipe 103 at appropriate intervals; simultaneously, rectangular steel plates 102 of matching dimensions are cut and the grouting holes 111 are pre-drilled. Shear studs 108 are welded to the inner side of the steel plates 102, and then the four steel plates 102 are welded together to form the first steel pipe. Next, the first annular rib 104, vertical rib 105, and corrugated plate are sequentially welded to the inner wall of the first steel pipe. The lower end of the vertical rib 105 is welded to the upper end face of the first annular rib 104, and the upper end of the corrugated plate is welded to the lower end face of the first annular rib 104.

[0026] After internal welding is completed, epoxy resin adhesive 109 is applied to the outer surface of the first steel pipe and sand is applied to form a robust, rough surface layer. A precast template is then placed and positioned, and ECC material 201 is poured to form an ECC shell 101. After compaction by vibration, it is cured according to regulations. Subsequently, epoxy resin adhesive 109 is applied and sand is applied at a certain distance from the outer end of the second steel pipe 103. It is then hoisted and placed inside the first steel pipe. After precise positioning, ordinary concrete 110 is poured into the first pouring cavity. At this point, a second pouring cavity 112 is formed between the first steel pipe and the corrugated plate to facilitate subsequent assembly and connection.

[0027] The prefabrication of the second assembly 2 includes the following steps: First, the reinforcing cage is tied according to the design specifications. It consists of longitudinal bars 202, SMA lap bars 203, and stirrups 204. The four peripheral longitudinal bars 202 use ordinary reinforcing bars, while the other bars are replaced with SMA lap bars 203 at the joints, forming the longitudinal bar connection section. The longitudinal bars in the connection section are all customized according to the actual dimensions of the variable cross-section, with their upper ends bent into the specific shape required by the design and extending to a predetermined height to fit the inner cavity of the first steel pipe. During the reinforcing bar tying process, a PVC pipe of a predetermined diameter is placed at the center of the reinforcing cage; this pipe will serve as a permanent weight-reducing cavity template. After the reinforcing cage is tied, a template is erected on its exterior, followed by the pouring of ECC material 201. After compaction by vibration, it is cured according to the prescribed procedure. A specific thickness of ECC material 201 is poured at the top and bottom of the PVC pipe to ensure the formation of a complete sealed cavity and lower the center of gravity.

[0028] II. On-site assembly; First, the prefabricated first assembly 1 and second assembly 2 are transported to the designated offshore construction location.

[0029] Subsequently, the longitudinal rib 202 connecting part of the second assembly 2 is accurately placed into the second casting cavity 112 reserved in the first assembly 1. Then, UHPC is poured into the second casting cavity 112 through the preset grouting hole 111, so that the two are combined into a whole.

[0030] Special attention should be paid to strictly implementing vibration compaction during the pouring process to ensure that the UHPC completely fills all voids and reaches a dense state, followed by curing according to regulations. Once the UHPC reaches its design strength, the floating foundation will have its design bearing capacity.

[0031] Finally, a wind turbine tower or other upper structure can be installed on the upper part of the second steel pipe 103.

[0032] The proposed solution decomposes the massive structure into two independent, standardized prefabricated modules, significantly reducing the difficulty and cost of manufacturing, transportation, and hoisting. It is suitable for rapid deployment in site-constrained and deep-sea environments. Furthermore, the second casting cavity 112 reserved in this structure is easier to align precisely with the two sides of the structure compared to the traditional grouting corrugated pipe connection method, resulting in high assembly efficiency.

[0033] The above are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions that fall within the scope of this utility model's concept are protected by this utility model.

[0034] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0036] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0037] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

Claims

1. A prefabricated ECC-steel composite offshore wind turbine floating foundation, characterized in that, It includes a first assembly part (1) and a second assembly part (2) connected below the first assembly part (1); The first assembly (1) includes a first steel pipe, an ECC shell (101) cast outside the first steel pipe, a first annular rib (104) connected inside the first steel pipe, a second steel pipe (103) disposed at the center of the first steel pipe, and a plurality of connecting plates (107) surrounding and connected to the lower end face of the first annular rib (104); a first pouring cavity for casting ordinary concrete (110) is formed between the first steel pipe, the second steel pipe (103), the first annular rib (104) and the connecting plates (107); a second pouring cavity (112) for casting UHPC concrete (3) is formed between the first steel pipe and the connecting plates (107). The second assembly (2) includes a reinforcing cage and a pipe (205) disposed within the reinforcing cage to form a cavity; the upper end of the reinforcing cage is provided with a longitudinal reinforcement connecting part, which surrounds and forms a shape adapted to the inner cavity of the first steel pipe, and is inserted into the second casting cavity (112); after the reinforcing cage is supported by formwork, a third casting cavity is formed between it and the pipe (205), and the third casting cavity is filled with ECC material (201).

2. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, The connecting plate (107) is a corrugated plate.

3. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, The first steel pipe is a square steel pipe formed by welding four steel plates (102); the second steel pipe (103) is a circular steel pipe.

4. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, It also includes a vertical rib (105) which is connected to the inner wall of the first steel pipe and the upper end face of the first annular rib (104); a second annular rib (106) is also provided on the inner wall of the second steel pipe (103).

5. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, A grouting hole (111) is provided on the side wall of the first steel pipe below the first annular rib (104).

6. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, Shear studs (108) are provided on the inner wall of the first steel pipe.

7. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, Before casting the ECC shell (101), epoxy resin adhesive (109) needs to be applied to the outer surface of the first steel pipe and sand should be planted.

8. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, Before pouring concrete into the first pouring cavity, the outer peripheral wall of the second steel pipe (103) placed inside the first steel pipe is coated with epoxy resin adhesive (109) and sand is planted.

9. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, The longitudinal bars (202) at the upper end of the steel cage and the SMA lap bars (203) disposed between the longitudinal bars (202) are bent to form the longitudinal bar connection.

10. The prefabricated ECC-steel composite offshore wind turbine floating foundation according to claim 1, characterized in that, The fitting (205) is made of PVC pipe. After the ECC material (201) is poured into the third casting cavity, a closed cavity is formed inside the PVC pipe.

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