A device and method for improving uplift capacity by changing the failure mode of suction foundations
By altering the failure mode of suction foundations through interlaced mesh and drilling components, the problem of limited pull-out bearing capacity and the contradiction between penetration resistance are solved, thereby improving pull-out performance and facilitating construction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHANDONG UNIV OF SCI & TECH
- Filing Date
- 2026-04-30
- Publication Date
- 2026-06-12
AI Technical Summary
Existing suction foundations have limited pull-out bearing capacity during the uplift process, poor failure modes, unfavorable drainage conditions, and difficulty in balancing penetration resistance and pull-out bearing capacity.
By employing an interlaced mesh and drilling component structure, and through the staggered arrangement of drilling components and wing plate design, the failure mode is altered, transforming the suction foundation from a local shear failure mode to a bottom tension failure mode. This utilizes the pull-out potential of the internal soil and reduces resistance during the penetration stage.
It significantly improves tensile bearing capacity, improves drainage conditions, reduces penetration resistance, facilitates construction, makes full use of soil strength, and enhances tensile performance.
Smart Images
Figure CN122190293A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of marine engineering technology, specifically to a device and method for improving pull-out bearing capacity by altering the failure mode of suction foundations. Background Technology
[0002] Suction foundations are a widely used type of foundation in marine engineering, such as offshore wind power, offshore oil and gas platforms, and anchoring of floating structures. Their working principle primarily involves negative pressure penetrating the seabed, relying on the interfacial friction between the foundation sidewalls and the soil, as well as the resistance provided by the soil at the foundation's base, to provide pull-out bearing capacity.
[0003] Existing suction foundations have the following problems when bearing uplift loads:
[0004] First, the failure mode is undesirable. During the uplift process, the internal soil of traditional suction foundations is often pulled out as a whole in the form of a "plug," resulting in local shear failure. Its pull-out bearing mechanism mainly relies on the interfacial friction between the foundation sidewall and the soil. The pull-out potential of the internal soil is not effectively utilized, resulting in limited pull-out bearing capacity.
[0005] Secondly, the drainage condition is unfavorable. Under static or slow loading conditions, the soil around the foundation is usually in a drained or near-drained state, with low effective stress and insufficient shear strength, which further limits the pull-out performance.
[0006] Secondly, there is a contradiction between penetration resistance and pull-out bearing capacity. In existing technologies, structures added to improve pull-out bearing capacity (such as extended wings, anchor plates, etc.) often significantly increase penetration resistance during the penetration stage, increasing construction difficulty and cost.
[0007] Therefore, there is an urgent need for a device and method that can change the failure mode of suction foundations, effectively utilize the pull-out potential of the internal soil, and take into account the penetration performance. Summary of the Invention
[0008] The purpose of this invention is to provide a device and method for improving pull-out bearing capacity by changing the failure mode of suction foundations, so as to solve the problems of limited pull-out bearing capacity, poor drainage response, and difficulty in balancing penetration resistance and pull-out bearing capacity in the prior art.
[0009] To achieve the above objectives, the present invention provides the following technical solution:
[0010] A device for improving pull-out bearing capacity by altering the failure mode of a suction foundation includes a suction anchor and a penetration and pull-out device disposed inside the suction anchor.
[0011] The suction anchor includes an inner wall and an outer wall.
[0012] The penetration and pull-out device includes an interlaced mesh, segmented fixing components, and a soil drilling component.
[0013] The interlaced mesh is fixed to the inner wall of the suction anchor by the segmented fastener.
[0014] The staggered mesh includes a first staggered mesh and a second staggered mesh, which are spaced apart along the axial direction of the suction anchor. The second staggered mesh is located below the first staggered mesh. Each staggered mesh has multiple mounting positions. Multiple drilling components are distributed at intervals within the corresponding staggered mesh. The drilling components installed on the first staggered mesh and the second staggered mesh are staggered on the horizontal projection plane.
[0015] The drilling component includes a support plate, a limiting component, a rotating shaft, and a wing plate.
[0016] The limiting member is set at a predetermined position on the support plate to reduce the damage caused by the compression between the wing plate and the support plate during penetration, and to keep the wing plate in a preset tilted posture in the closed state, so as to facilitate the smooth unfolding during the pull-out stage.
[0017] The wing plates are symmetrically arranged on both sides of the lower part of the support plate. The two wing plates arranged in pairs are rotatably connected to the support plate through the same pivot, so that the wing plates can rotate relative to the support plate between the closed position and the unfolded position.
[0018] The rotating shaft is equipped with a limiting structure that restricts the rotation angle of the wing plate.
[0019] During the penetration stage, the soil resistance forces the flange to rotate around the axis and fit against the limiting member, thereby reducing the additional resistance generated by the drilling component during the penetration of the suction anchor. During the pull-out stage, the soil resistance forces the flange to rotate and unfold around the axis, so that the drilling components located on different interlaced grids form spatially staggered pull-out action surfaces, thereby improving the pull-out bearing capacity of the suction foundation.
[0020] The aforementioned structure transforms the failure mode of suction foundations from local shear failure to bottom tension failure, causing the soil to exhibit a partially drained or nearly undrained response during uplift, thereby improving its pull-out bearing capacity.
[0021] A method for improving the pull-out bearing capacity of a suction foundation by altering its failure mode using the aforementioned device includes the following steps:
[0022] S1. Determine the relevant parameters of the staggered mesh: Based on the structural dimensions of the suction anchor, the design pull-out bearing capacity requirements, the soil properties and the design burial depth, determine the number of layers of the staggered mesh, the axial spacing between adjacent staggered meshes, the number of drilling components in each layer and their installation positions on the staggered mesh, and make the drilling components of adjacent layers staggered on the horizontal projection plane.
[0023] S2. Assemble the drilling components, including setting a limiting component on the support plate, setting a rotating shaft at the lower part of the support plate, and rotatably connecting wing plates on both sides of the lower part of the support plate through the rotating shaft;
[0024] S3. Fix each layer of staggered mesh to the inner wall of the suction anchor using segmented fasteners, and install the corresponding number of drilling components at the installation positions of each layer of staggered mesh, so that the drilling components of adjacent layers are staggered.
[0025] S4. Pump water from the suction anchor to create a pressure difference between the inside and outside of the suction anchor, and then drive the suction anchor into the seabed to the design depth under negative pressure. During the penetration process, the flanges on each drilling component rotate around the axis of the support plate and fit against the limiting component under the action of soil resistance.
[0026] S5. When the suction anchor is subjected to uplift load, the flanges on each drilling component rotate and unfold around the axis under the action of soil resistance until they are restricted and stopped by the limiting structure. This causes the drilling components on the adjacent interlaced grid to form a spatially interlaced uplift resistance surface in the soil, thereby improving the uplift bearing capacity of the suction foundation.
[0027] Compared with the prior art, the present invention has the following beneficial effects:
[0028] By changing the failure mode and significantly improving the pull-out bearing capacity: through the staggered arrangement of the drilling parts on the adjacent interlocking mesh and the unfolding of the wing plate in the pull-out stage, the suction foundation is transformed from the traditional local shear failure mode to the bottom tension failure mode, which effectively expands the range of internal soil participating in the stress, fully mobilizes the pull-out potential of the internal soil, and solves the problem of limited pull-out bearing capacity of existing technology.
[0029] Improve drainage conditions and make full use of soil strength: By changing the failure mode, the soil exhibits a partially drained or nearly undrained response under non-rapid uplift conditions. This is different from traditional suction foundations, which require rapid uplift to achieve the undrained effect. Thus, the strength enhancement effect of the soil is utilized without increasing the uplift rate, further enhancing the uplift resistance of the foundation.
[0030] Low penetration resistance and convenient construction: By designing the wing plate to fit the limiting component during the penetration stage, the increase in penetration resistance is smaller compared to the existing scheme that adds a fixed external expansion structure; the segmented fixing component structure is simple and easy to disassemble and assemble, which solves the contradiction between penetration resistance and pull-out bearing capacity. Attached Figure Description
[0031] The accompanying drawings are used to further illustrate the technical solutions of the present invention and constitute a part of this specification. The illustrative embodiments of the present invention and their descriptions are only for explaining the present invention and do not constitute a limitation on the scope of protection of the present invention.
[0032] Figure 1 This is a schematic diagram of the failure modes of the suction base of the present invention, wherein (a) is the local shear failure mode and (b) is the bottom tension failure mode;
[0033] Figure 2 This is a schematic diagram of the appearance of the present invention;
[0034] Figure 3 This is a cross-sectional front view of the present invention;
[0035] Figure 4 This is a schematic diagram showing the staggered arrangement of the first and second staggered network disks of the present invention;
[0036] Figure 5 This is a front view of the drilling component of the present invention during the penetration stage;
[0037] Figure 6 This is a side view of the drilling component of the present invention during the penetration stage;
[0038] Figure 7 This is a front view of the working stage of the drilling component of the present invention.
[0039] in:
[0040] 1—Suction anchor; 11—Inner wall of suction anchor; 12—Outer wall of suction anchor;
[0041] 2—Penetration and pull-out device; 21—Interlaced mesh disc; 211—First interlaced mesh disc; 212—Second interlaced mesh disc; 22—Segmented fixing component; 23—Soil drilling component; 231—Support plate; 232—Limiting component; 233—Rotating shaft; 234—Wing plate. Detailed Implementation
[0042] To more clearly illustrate the technical solution of the present invention, a detailed description is provided below with reference to the accompanying drawings. The embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.
[0043] This invention provides a device and method for improving pull-out bearing capacity by altering the failure mode of a suction foundation. The following is in conjunction with... Figures 1 to 7 The specific embodiments of the present invention will be described in detail below.
[0044] like Figure 1 As shown, this invention improves the pull-out bearing capacity by changing the pull-out failure mode of the suction foundation from a local shear failure mode to a bottom tension failure mode, and by causing the internal soil to exhibit a partially drained or nearly undrained response under non-rapid pull-out conditions.
[0045] in, Figure 1(a) shows the traditional local shear failure mode. When the suction foundation is pulled out, the resistance mainly comes from the foundation's own weight and the interfacial friction between the inner and outer walls of the foundation and the soil. The pull-out force can be approximately expressed as: Vt≈G+Vfo+Vfi, where Vt is the pull-out force; G is the foundation's own weight; Vfi is the friction between the inner wall of the foundation and the soil; and Vfo is the friction between the outer wall of the foundation and the soil.
[0046] And in Figure 1 (b) shows the bottom tension failure mode, in which the soil inside the foundation participates in the stress as a whole and rises together with the foundation. In addition to the foundation's own weight and the friction of the outer wall, the resistance contribution also includes the self-weight of the internal soil plug and the tension at the bottom of the soil plug. Its pullout force can be approximately expressed as: Vt≈G+Vfo+W+Vb, where W is the self-weight of the soil plug and Vb is the ultimate tension at the bottom of the soil plug. Since W+Vb is significantly greater than Vfi, this mode increases the additional resistance formed by the overall participation of the internal soil in pullout resistance, thus significantly improving the pullout bearing capacity of the foundation.
[0047] like Figure 2 , Figure 3 As shown, a device for improving pull-out bearing capacity by changing the failure mode of a suction foundation includes a suction anchor 1 and a penetration and pull-out device 2 disposed inside the suction anchor 1.
[0048] The suction anchor 1 has a suction anchor inner wall 11 and a suction anchor outer wall 12.
[0049] The penetration and pull-out device 2 includes an interlaced mesh disc 21, a segmented fixing member 22, and a drilling component 23. The interlaced mesh disc 21 is fixed to the inner wall 11 of the suction anchor by the segmented fixing member 22. The interlaced mesh disc 21 includes a first interlaced mesh disc 211 and a second interlaced mesh disc 212 spaced apart along the axial direction of the suction anchor 1, with the second interlaced mesh disc 212 located below the first interlaced mesh disc 211. Both the first interlaced mesh disc 211 and the second interlaced mesh disc 212 are provided with multiple mounting positions for installing the drilling component 23. Multiple drilling components 23 are installed in the disc surface of the corresponding interlaced mesh disc 21, and the drilling components 23 installed on the first interlaced mesh disc 211 and the second interlaced mesh disc 212 are staggered in the horizontal projection plane.
[0050] like Figure 4As shown, the staggered mesh disk 21 is a disc-shaped installation structure, with its periphery fixed to the inner wall 11 of the suction anchor 1 by segmented fixing members 22. An internal support frame is provided, forming multiple installation positions for the drilling components 23. The support frame can be a grid-like, spoke-like, fan-shaped spliced structure, or a combination thereof. Multiple drilling components 23 are spaced apart within the surface of the staggered mesh disk 21. The segmented fixing members 22 are multiple fixing segments spaced apart along the circumference of the staggered mesh disk 21, used to fix the staggered mesh disk 21 to the inner wall 11 of the suction anchor. In this embodiment, the drilling components 23 on the upper and lower layers of the staggered mesh disk 21 are staggered on the horizontal projection plane to avoid overlapping of corresponding positions and to expand the stress range of the soil inside during the pull-out stage.
[0051] like Figure 5 , Figure 6 , Figure 7 As shown, the drilling component 23 includes a support plate 231, a limiting member 232, a rotating shaft 233, and wing plates 234. The limiting member 232 is positioned at a predetermined location on the support plate 231 to reduce damage caused by compression between the wing plates 234 and the support plate 231 during penetration, and to maintain a preset tilted posture of the wing plates 234 in the closed state, facilitating smooth deployment during the pull-out stage. The wing plates 234 are symmetrically arranged on both sides of the lower part of the support plate 231. The two paired wing plates 234 are rotatably connected to the support plate 231 via the same rotating shaft 233, allowing the wing plates 234 to rotate relative to the support plate 231 between the closed and deployed positions. The rotating shaft 233 is provided with a limiting structure to restrict the rotation angle of the wing plates 234, ensuring that the wing plates 234 stop after deploying to a predetermined angle during the pull-out stage.
[0052] During the penetration stage, the soil resistance forces the wing plate 234 to rotate around the pivot 233 and fit against the limiting member 232, thereby reducing the additional resistance generated by the drilling component 23 on the suction anchor 1 during penetration. During the pull-out stage, the soil resistance forces the wing plate 234 to rotate and unfold around the pivot 233. The wing plate 234 interacts with the surrounding soil, causing the drilling components 23 on the different layers of the interlaced mesh 21 to form spatially interlaced pull-out action surfaces, thereby effectively improving the pull-out bearing capacity of the suction foundation.
[0053] Since the drilling components 23 installed on the first staggered mesh disk 211 and the second staggered mesh disk 212 are staggered on the horizontal projection plane, during the pull-out stage, after the wing plates 234 of each drilling component 23 rotate from the closed position to the unfolded position, the adjacent layers of drilling components 23 form a staggered and unfolded spatial force structure, forming a pull-out action surface in the soil that is layered along the axial direction and staggered along the horizontal projection direction, thereby increasing the range of the soil inside the suction anchor 1 participating in the pull-out.
[0054] The unfolded wing plate 234 and the staggered soil drilling components 23 work together to expand the upward load from acting only on the local soil adjacent to the foundation to being transmitted to the entire soil inside the foundation, forcing the failure area to expand from near the foundation sidewall to the tension area of the wing plate 234, thereby changing the failure mode from local shear failure mode to bottom tension failure mode.
[0055] like Figure 1 – Figure 7 As shown, this embodiment provides a method for improving the pull-out bearing capacity of a suction foundation using the above-mentioned device, specifically including the following steps:
[0056] S1 determines the parameters of the interleaved cloud drive (see...) Figures 2-4 )
[0057] Based on the structural dimensions of the suction anchor 1, the design pull-out bearing capacity requirements, soil properties, and design burial depth, the number of layers of the staggered mesh 21 (e.g., two, three, or more layers) is determined, and accordingly, the axial spacing between adjacent staggered meshes 21, the number of drilling components 23 in each layer, and the predetermined installation position of each drilling component 23 on the staggered mesh 21 are determined. Simultaneously, the drilling components 23 in adjacent layers are staggered on the horizontal projection plane to form a spatially staggered stress structure during the pull-out stage.
[0058] S2 assembled drilling component 23 (see Figures 5-7 )
[0059] S2-1: Component preparation. Based on the number of drilling components 23 determined in S1, prepare support plate 231, limiting component 232, rotating shaft 233 and wing plate 234.
[0060] S2-2: Install the limiting component. Install the limiting component 232 symmetrically at predetermined positions on the support plate 231. The limiting component 232 serves as a buffer and protector when the wing plate 234 rotates towards the support plate 231 and fits against the limiting component 232 during the subsequent penetration stage, reducing damage caused by compression between the wing plate 234 and the support plate 231. Simultaneously, it maintains a preset tilted posture for the wing plate 234 in the closed state, facilitating its smooth deployment during the pull-out stage.
[0061] S2-3: Install the pivot. Install the pivot 233 on the lower part of the support plate 231, and set a limiting structure on the pivot 233. The limiting structure is used to limit the deployment angle of the wing plate 234 during the pull-out stage.
[0062] S2-4: Install wing plates. Install wing plates 234 symmetrically on both sides of the lower part of the support plate 231, and rotatably connect the two pairs of wing plates 234 to the support plate 231 via the same pivot 233. After installation, the wing plates 234 can rotate relative to the support plate 231 between the closed position and the deployed position, and cooperate with the limiting member 232 to keep the wing plates 234 in a preset tilted posture in the closed state, thereby reserving rotation conditions for deployment during the pull-out stage.
[0063] S3 Assembly Suction Anchor 1 (see) Figures 2-4 )
[0064] S3-1: Install the first interlaced mesh disc. Fix the first interlaced mesh disc 211 to a predetermined height position on the inner wall 11 of the suction anchor using segmented fasteners 22, and then install the corresponding number of drilling components 23 at the predetermined installation positions of the first interlaced mesh disc 211.
[0065] S3-2: Install the second interlaced mesh disc. The second interlaced mesh disc 212 is fixed to the inner wall 11 of the suction anchor using segmented fasteners 22. The second interlaced mesh disc 212 is located below the first interlaced mesh disc 211, and the two are spaced apart along the axial direction of the inner wall 11 of the suction anchor. Install the corresponding number of drilling components 23 at their designated installation positions on the second interlaced mesh disc 212.
[0066] S3-3: Install other staggered mesh panels as needed. If three or more staggered mesh panels 21 need to be set up, repeat step S3-2 and ensure that the drilling components 23 of adjacent layers are staggered on the horizontal projection plane.
[0067] S4 Penetration Suction Anchor 1 (see...) Figures 2-7 )
[0068] The assembled suction anchor 1 is lowered to the seabed surface, and water is pumped out of the suction anchor 1 to create a pressure difference between the inside and outside of the suction anchor 1. Under negative pressure, the suction anchor 1 is driven into the seabed to the designed depth. During the penetration process, the flanges 234 on each drilling component 23 rotate around the pivot 233 towards the support plate 231 under the action of soil resistance, and fit against the surface of the limiting component 232, thereby effectively reducing the additional resistance generated by the drilling components 23 on the penetration process of the suction anchor 1.
[0069] S5 tensile bearing stage (see...) Figures 1-7 )
[0070] When the suction anchor 1 is subjected to an uplift load, the flanges 234 on each drilling component 23 rotate and unfold in the opposite direction around the axis 233 under the action of soil resistance, until they are stopped by the limiting structure on the axis 233 and remain at the predetermined unfolding angle. At this time, the flanges 234 of the drilling components 23 staggered on the adjacent layered grid 21 form an uplift-resistant surface in the soil that is layered along the axial direction and staggered along the horizontal projection direction.
[0071] Under the action of the pull-out surface, the soil inside the suction anchor 1 is subjected to layered embedment and synergistic restraint during the pull-out process. The potential failure area expands from near the foundation sidewall to the tensioning area of the wing plate 234, inhibiting the internal soil from being pulled out as a whole in a plug-like form along a single continuous slip surface. This causes the pull-out failure mode to change from local shear-dominated to a synergistic failure mode involving a larger range of soil, namely the bottom tension failure mode. The internal soil changes from passively following the pull-out force to actively participating in the pull-out force and resists the pull-out load together with the foundation sidewall.
[0072] Simultaneously, under this failure mode, the stress path and pore pressure response of the internal soil change, creating conditions unfavorable for timely dissipation of pore pressure. This causes the soil to exhibit a partially drained or nearly undrained response under non-rapid uplift conditions. Unlike traditional suction foundations, which typically require rapid uplift to achieve the undrained effect, this method, by altering the failure mode, can achieve a soil strength enhancement effect without increasing the uplift rate, thereby improving the uplift bearing capacity. The activation effect of internal soil resistance brought about by the change in failure mode, combined with the soil strength enhancement effect brought about by the change in drainage state, mutually enhances the uplift bearing capacity of the suction foundation.
[0073] It is understood that the specific embodiments of the present invention are not limited to the above-described embodiments. The interlaced mesh disk 21 is a disc-shaped installation structure, and its internal support frame is not limited to a mesh shape, but can also adopt a spoke-type frame, a fan-shaped splicing structure, or a combination of the above structures, as long as it can form multiple installation positions for installing the drilling component 23. In addition to using circumferentially spaced fixing segments, the segmented fixing component 22 can also use welding, bolt connection, snap-fit, or plug-in methods to fix the interlaced mesh disk 21 to the inner wall 11 of the suction anchor. The shape of the wing plate 234 is not limited to the rectangular plate shown in the figure, but can also be a triangular plate, trapezoidal plate, or arc plate, as long as it can rotate and unfold relative to the support plate 231 and form a pull-out resistance. These alternative solutions are all within the protection scope of the present invention.
[0074] Through the above structure and method, the failure mode of the suction foundation is changed from local shear failure mode to bottom tension failure mode, so that the soil exhibits a partially drained or nearly undrained response under non-rapid uplift conditions. The strength enhancement effect can be obtained without increasing the uplift rate, thereby improving the uplift bearing capacity.
[0075] The above description is merely an embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art can make various modifications, equivalent substitutions, or improvements to the present invention without departing from its spirit and principles, and all such modifications, substitutions, or improvements should fall within the protection scope of the present invention.
Claims
1. A device for altering the failure mode of a suction foundation to improve its pull-out bearing capacity, characterized in that, Includes a suction anchor, and a penetration and pull-out device disposed inside the suction anchor; The penetration and pull-out device includes an interlaced mesh, segmented fixing components, and a soil drilling component; The interlaced mesh is fixed to the inner wall of the suction anchor by the segmented fastener; The staggered mesh includes a first staggered mesh and a second staggered mesh, which are spaced apart along the axial direction of the suction anchor. Each staggered mesh has multiple mounting positions for installing the drilling components. Multiple drilling components are installed in the corresponding surface of the staggered mesh, and the drilling components installed on the first staggered mesh and the second staggered mesh are staggered on the horizontal projection plane. The drilling component includes a support plate, a limiting component, a rotating shaft, and wing plates. The limiting component is disposed on the support plate, and the wing plates are symmetrically disposed on both sides of the lower part of the support plate. The two wing plates disposed in pairs are rotatably connected to the support plate through the same rotating shaft, so that the wing plates can rotate relative to the support plate between a closed position and an open position. The rotating shaft is provided with a limiting structure to restrict the rotation angle of the wing plate; during the penetration stage, the wing plate can rotate around the rotating shaft and fit against the limiting structure under the action of soil resistance, so as to reduce the additional resistance generated by the drilling component to the suction anchor during the penetration process; during the pull-out stage, the wing plate can rotate and unfold around the rotating shaft under the action of soil resistance, so that the drilling components located on different interlaced grids form a spatially interlaced pull-out action surface, thereby improving the pull-out bearing capacity of the suction foundation.
2. The device for changing the failure mode of a suction foundation and improving its pull-out bearing capacity according to claim 1, characterized in that: The second interleaved disk is located below the first interleaved disk.
3. The device for changing the failure mode of a suction foundation and improving its pull-out bearing capacity according to claim 1, characterized in that: The limiting structure is a baffle, limiting boss, or elastic limiting member set on the rotating shaft.
4. The device for changing the failure mode of a suction foundation and improving its pull-out bearing capacity according to claim 1, characterized in that: The interlaced mesh is a disc-shaped installation structure. Its periphery is fixed to the inner wall of the suction anchor by segmented fasteners. The interior is provided with a support frame for forming multiple installation positions for installing the drilling component.
5. The device for changing the failure mode of a suction foundation and improving its pull-out bearing capacity according to claim 1, characterized in that: The segmented fastener consists of multiple fixed segments spaced apart along the circumference of the interlaced mesh disk, used to fix the interlaced mesh disk to the inner wall of the suction anchor.
6. The device for changing the failure mode of a suction foundation and improving its pull-out bearing capacity according to claim 1, characterized in that: The wing plate is a rectangular plate, a triangular plate, a trapezoidal plate, or an arc plate.
7. The device for changing the failure mode of a suction foundation and improving its pull-out bearing capacity according to claim 1, characterized in that: The staggered mesh is configured with two, three or more layers, and the drilling components on adjacent staggered meshes are arranged in a staggered manner on the horizontal projection plane.
8. A method for improving the pull-out bearing capacity of a suction foundation using the device according to any one of claims 1-7, characterized in that, Includes the following steps: S1. Based on the structural dimensions of the suction anchor, the design pull-out bearing capacity requirements, the soil properties and the design burial depth, determine the number of layers of the staggered mesh, the axial spacing between adjacent staggered meshes, the number of drilling components in each layer and their installation positions on the staggered mesh, and arrange the drilling components of adjacent layers in a staggered manner on the horizontal projection plane. S2. Assemble the drilling components, including setting a limiting component on the support plate, setting a rotating shaft at the lower part of the support plate, and rotatably connecting wing plates on both sides of the lower part of the support plate through the rotating shaft; S3. Fix each layer of staggered mesh to the inner wall of the suction anchor using segmented fasteners, and install the corresponding number of drilling components at the installation positions of each layer of staggered mesh, so that the drilling components of adjacent layers are staggered. S4. Pump water from the suction anchor to create a pressure difference between the inside and outside of the suction anchor, and then drive the suction anchor into the seabed to the design depth under negative pressure. During the penetration process, the flanges on each drilling component rotate around the axis of the support plate and fit against the limiting component under the action of soil resistance. S5. When the suction anchor is subjected to uplift load, the flanges on each drilling component rotate and unfold around the axis under the action of soil resistance until they are restricted and stopped by the limiting structure. This causes the drilling components on the adjacent interlaced grid to form a spatially interlaced uplift resistance surface in the soil, thereby improving the uplift bearing capacity of the suction foundation.
9. The method according to claim 8, characterized in that: In step S5, the pull-out failure mode of the suction base changes from the local shear failure mode to the bottom tension failure mode.
10. The method according to claim 8, characterized in that: In step S5, the internal soil exhibits a partially drained or nearly undrained response under non-rapid uplift conditions.