Foundation scouring prevention pile shoe node structure for offshore platform

Abstract

The invention discloses a pile shoe node structure for preventing foundation scouring for an offshore platform, which is characterized in that the pile shoe node structure comprises a steel pipe pile, a jacket main leg, a pile shoe, a connecting plate and a spoiler, the pile shoe is arranged at the bottom of the jacket main leg and is connected with the steel pipe pile and the jacket main leg; one end of the connecting plate is fixed on the pile shoe, and the other end of the connecting plate is connected with the spoiler; a reserved hole is formed in the joint of the spoiler and the connecting plate. Compared with the prior art, the spoiler adopted by the invention is a conventional steel plate, so that the cost is low; and the size and the arrangement angle of the spoiler are configured to be optimized and adjusted according to numerical simulation and water tank test results, so that local flow field distribution can be changed to the maximum extent, and formation and expansion of a scouring pit around the pile are effectively weakened. Meanwhile, a standard mechanical bolt structure is used for connection, the construction period is relatively short, the structure is simple, the spoiler is easy to disassemble and replace, the pile shoe node structure is greatly used for the offshore platform for preventing the foundation from being scoured, and the operability of later maintenance is improved.

Description

Technical Field

[0001] This application relates to the field of offshore wind power foundation engineering, and in particular to a pile shoe node structure for preventing foundation scour of offshore platforms. Background Technology

[0002] Jacket scour is a significant and common problem in marine engineering, typically occurring around the foundations of offshore platforms, bridge piers, and other marine structures. It is primarily caused by water currents (including tides and waves) scouring away seabed sediment, resulting in a localized drop in seabed elevation around the foundation and the formation of scour pits. This phenomenon significantly reduces structural stability and, in severe cases, can even lead to structural instability or overturning.

[0003] The primary cause of scouring is the effect of horseshoe vortices: when water flows against obstacles such as the legs of a jacket structure, it creates flow around the structure in front of and to the sides of the flow-facing side. Directly in front, the water flow is obstructed and the pressure increases, forcing some of the water downwards towards the seabed. Subsequently, it swirls upwards from the sides of the structure, forming a horseshoe-shaped vortex system.

[0004] As the scale of offshore wind power continues to expand, offshore substations and converter stations, as key hubs in the power transmission system, must possess long-term stability in their foundation structures. Currently, the foundations of these platforms widely adopt pile-shoe jacket structures. However, under the long-term hydrodynamic forces of tides and waves, the soil around the piles is prone to localized erosion, resulting in exposed piles and reduced bearing capacity, thus threatening the safety of the entire superstructure.

[0005] Currently, the following methods can be used to prevent seabed erosion:

[0006] Rockfill: Gravel or boulders of a certain grade are dumped around the foundation of a structure to reduce the energy of water flow and cover easily eroded soil layers using their weight and porosity. This method is simple to construct, but it has disadvantages such as easy loss of stone, frequent maintenance, significant impact on the seabed ecological environment, and difficulty in precision control.

[0007] Flexible protective mats: These are sand mats made of geotextile-wrapped stones or flexible mats made of interlocking concrete blocks. These mats are laid over a large area on the seabed and can effectively disperse the shear force of water flow and protect the underlying sediment. However, they have limitations such as complex construction technology, high overall cost and poor adaptability to irregular seabed topography.

[0008] Pile foundation shape optimization: Using non-circular cross-sections (such as wing-shaped or polygonal piles) to change the vortex shedding mode. Although this method can reduce scour from the design stage, it is often more expensive to manufacture.

[0009] Therefore, there is an urgent need for a pile shoe node structure that can improve the flow field in the wake region, reduce vortex shedding, and has the advantages of convenient construction, controllable construction quality, low cost, and good anti-scour effect. Summary of the Invention

[0010] The inventors of this application, through extensive research, have developed a pile shoe node structure that improves the flow field in the wake region, reduces vortex shedding, and has advantages such as convenient construction, controllable construction quality, low cost, and good scour prevention effect. The specific details disclosed are as follows:

[0011] This application discloses a pile shoe node structure for preventing foundation scour of offshore platforms. The pile shoe node structure includes: steel pipe piles, jacket supports, pile shoes, connecting plates, and spoilers, wherein:

[0012] The pile shoe is configured to connect the steel pipe pile and the guide frame;

[0013] One end of the connecting plate is fixed to the pile shoe, and the other end is connected to the spoiler.

[0014] The spoiler and the connecting plate are provided with reserved holes, and the reserved holes of the spoiler and the connecting plate correspond one-to-one.

[0015] In a preferred embodiment, the connection between the spoiler and the connecting plate includes a bolted connection.

[0016] In a preferred embodiment, the bolt is configured as a high-strength bolt.

[0017] In a preferred embodiment, the reserved holes are distributed circumferentially.

[0018] In a preferred embodiment, the connecting plate is a steel plate in the shape of a cuboid.

[0019] In a preferred embodiment, the number of spoilers and connecting plates is 2-6.

[0020] In a preferred embodiment, the connection between the connecting plate and the pile shoe includes a welding connection.

[0021] In a preferred embodiment, the size and arrangement angle of the spoiler are configured to be optimized based on numerical simulation and tank test results to achieve the best effect.

[0022] In a preferred embodiment, the connecting plate is disposed on the outer edge of the pile shoe.

[0023] In a preferred embodiment, the spoiler has the following dimensions: 3-10m in length, 2-9m in width, and 0.02m-0.08m in thickness, and is made of steel plate.

[0024] The main advantages of this invention are:

[0025] (1) The spoiler used in this invention is a conventional steel plate, which is inexpensive.

[0026] (2) The size and arrangement angle of the baffle plate configured in this invention are optimized and adjusted according to the results of numerical simulation and water tank test, so as to maximize the change of local flow field distribution and effectively reduce the formation and expansion of pile perimeter scour pit.

[0027] (3) The present invention uses a standard mechanical bolt structure connection, which not only has a relatively short construction period, but also has a simple structure that makes it easy to disassemble and replace the spoiler, greatly improving the operability of later maintenance.

[0028] (4) The present invention adopts a steel structure as a whole, with high overall rigidity, excellent load-bearing and fatigue resistance, and meets the requirements of long-term service.

[0029] The specification of this application contains numerous technical features distributed across various technical solutions. Listing all possible combinations of these technical features (i.e., technical solutions) would make the specification excessively lengthy. To avoid this problem, the various technical features disclosed in the above-described invention, the various technical features disclosed in the following embodiments and examples, and the various technical features disclosed in the accompanying drawings can be freely combined to form various new technical solutions (all of which should be considered as described in this specification), unless such a combination of technical features is technically infeasible. For example, one example discloses feature A+B+C, and another example discloses feature A+B+D+E. Features C and D are equivalent technical means that serve the same function, and technically only one needs to be used; they cannot be used simultaneously. Feature E can technically be combined with feature C. Therefore, the solution A+B+C+D should not be considered as described because it is technically infeasible, while the solution A+B+C+E should be considered as described. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the pile shoe node structure described in this invention;

[0031] Figure 2 This is a schematic diagram of the structure of the spoiler described in this invention;

[0032] Figure 3 This is a schematic diagram of the pile shoe node structure after installation according to the present invention.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1—Main leg of jacket; 2—Connecting plate; 3—Pile shoe; 4—Break plate; 5—Bolt. Detailed Implementation

[0035] Through in-depth and extensive research, the inventors of this invention have developed a pile shoe node structure for preventing foundation scour on offshore platforms. Compared with existing technologies, this invention uses conventional steel plates for the spoiler, resulting in lower costs. Furthermore, the size and arrangement angle of the spoiler are optimized based on numerical simulations and flume tests, thereby maximizing the alteration of the local flow field distribution and effectively reducing the formation and expansion of scour pits around the piles. Simultaneously, this application uses a standard mechanical bolt connection structure, which not only shortens the construction period but also simplifies the structure, facilitating the disassembly and replacement of the spoiler, significantly improving the operability of later maintenance for pile shoe node structures used to prevent foundation scour on offshore platforms. The entire invention employs a steel structure, exhibiting high overall rigidity, superior load-bearing and fatigue resistance, and meeting the requirements for long-term service.

[0036] the term

[0037] catheter stent

[0038] The jacket structure described in this invention is a support structure for offshore converter stations and offshore booster stations, consisting of hollow legs and longitudinal and transverse bars connecting the legs.

[0039] Pile boots

[0040] The pile shoe mentioned in this invention refers to the bottom support structure of the main leg of the jacket, which is used to connect with the steel pipe pile and transfer the upper load to the steel pipe pile;

[0041] flushing

[0042] The scouring described in this invention mainly refers to the phenomenon of soil displacement at the seabed contact point of marine engineering structures due to the impact of waves and ocean currents.

[0043] Example

[0044] This application is implemented for example Figures 1-3 As shown, a pile shoe node structure for preventing foundation scour on offshore platforms is disclosed, specifically including: steel pipe piles, jacket main legs 1, pile shoes 3, connecting plates 2, and spoilers 4, wherein:

[0045] The pile shoe 3 is disposed at the bottom of the main leg 1 of the jacket and connects the steel pipe pile (not shown in the figure) and the jacket;

[0046] One end of the connecting plate 2 is fixed to the pile shoe 3, and the other end is connected to the spoiler 4; the connecting plate 2 and the pile shoe 3 are connected by welding; the connecting plate 2 is disposed on the outer edge of the pile shoe 3.

[0047] The spoiler 4 and the connecting plate 2 are provided with reserved holes at their joint, and the reserved holes of the spoiler 4 and the connecting plate 2 correspond one-to-one. Optionally, in one embodiment, the spoiler 4 and the connecting plate 2 are bolted together through the reserved holes, and the bolts 5 are configured as high-strength bolts 5. Optionally, in another embodiment, the reserved holes are circumferentially distributed.

[0048] Optionally, in one embodiment, the connecting plate 2 is a rectangular steel plate, and the dimensions of the spoiler 4 are as follows: length 3-10m, width 2-9m, thickness 0.02m-0.08m, and the material is steel plate.

[0049] Optionally, in one embodiment, the number of spoilers 4 and connecting plates 2 is 2-6.

[0050] Alternatively, in another embodiment, the size and arrangement angle of the spoiler 4 are configured to be optimized and adjusted based on numerical simulation and tank test results to achieve the best effect.

[0051] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0052] It should be noted that in the invention documents of this patent, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. In the invention documents of this patent, if it refers to performing an action according to an element, it means performing the action at least according to that element, including two cases: performing the action only according to that element, and performing the action according to that element and other elements. Expressions such as "multiple," "repeatedly," and "various" include two, two times, two kinds, and more than two, more than two times, and more than two kinds.

[0053] All documents mentioned in this invention are considered to be incorporated integrally into the disclosure of this invention so that they can serve as the basis for modifications if necessary. Furthermore, it should be understood that the above are merely preferred embodiments of this specification and are not intended to limit the scope of protection of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments of this specification should be included within the scope of protection of one or more embodiments of this specification.

Claims

1. A pile shoe joint structure for preventing foundation scour in offshore platforms, characterized in that, The pile shoe node structure includes: steel pipe pile, main leg of jacket support, pile shoe, connecting plate and baffle plate, wherein: The pile shoe is disposed at the bottom of the main leg of the jacket and connects the steel pipe pile and the main leg of the jacket; One end of the connecting plate is fixed to the pile shoe, and the other end is connected to the spoiler. The spoiler and the connecting plate are provided with reserved holes, and the reserved holes of the spoiler and the connecting plate correspond one-to-one.

2. The pile shoe node structure according to claim 1, characterized in that, The connection method between the spoiler and the connecting plate includes: bolt connection.

3. The pile shoe node structure according to claim 2, characterized in that, The bolts are configured as high-strength bolts.

4. The pile shoe node structure according to claim 1, characterized in that, The reserved holes are distributed in a circular pattern.

5. The pile shoe node structure according to claim 1, characterized in that, The connecting plate is a steel plate in the shape of a cuboid.

6. The pile shoe node structure according to claim 1, characterized in that, The number of spoilers and connecting plates is 2-6.

7. The pile shoe node structure according to claim 1, characterized in that, The connection method between the connecting plate and the pile shoe includes: welding connection.

8. The pile shoe node structure according to claim 1, characterized in that, The size and arrangement angle of the spoiler are configured to be optimized and adjusted based on numerical simulation and water tank test results to achieve the best effect.

9. The pile shoe node structure according to claim 1, characterized in that, The connecting plate is disposed on the outer edge of the pile shoe.

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