Construction method of offshore wind power scouring flow state solidified soil-riprap composite scouring repair structure

Abstract

The invention relates to a construction method of an offshore wind power pile foundation flow state solidified soil-riprap composite scouring repairing structure. The structure comprises a bottom layer side wall solidified soil layer, a riprap filling layer and an overlying solidified soil protection layer from bottom to top. The pile foundation is naturally attached to the bottom layer side wall solidified soil layer, the riprap filling layer and the overlying solidified soil protection layer from bottom to top through construction. The bottom-layer side wall solidified soil layer is poured in the scouring pit by a certain thickness, the riprap filling layer is filled on the basis of the bottom-layer side wall solidified soil layer to be flush with the seabed surface, and the overlying solidified soil protective layer is poured on the bottom surface, the side wall solidified soil layer and the riprap filling layer. The bottom layer side wall surface solidified soil layer, the riprap filling layer and the overlying solidified soil protection layer are utilized to form a combined repair structure, the defects that traditional riprap protection is prone to generating pore scouring and riprap particles are prone to being washed away, so that the protection effect is poor are overcome, and the high cost caused by full pouring of solidified soil is also reduced.

Description

Technical Field

[0001] This invention relates to the field of marine engineering and renewable energy technology, specifically to a construction method for a composite scour repair structure of offshore wind power scour fluidized solidified soil-rock composite scour. Background Technology

[0002] Offshore wind turbine foundations are constantly subjected to dynamic factors such as waves and tides, and the seabed around the piles is prone to erosion, forming erosion pits. This can lead to local loss of support and decreased stability of the pile foundation, and in severe cases, it may endanger the safety of the entire platform structure.

[0003] Currently, common remediation measures include riprap backfilling, precast component sealing, and full-coverage solidified soil pouring. Chinese patent application CN120331307A discloses a construction method for solidified soil anti-scour of offshore wind turbine pile foundations, including the following steps: conducting topographic surveys of the scour pit before construction, determining the volume of dredging and filling and the filling points based on the data obtained from the surveys; transporting solidified soil to an area 3-5m away from the filling point using a work vessel, and using anchor boats to position the work vessel with four anchors; using a pump to fill the scour pit with the solidified soil from the work vessel, determining the filling construction steps based on the data obtained from the surveys, and filling the solidified soil by contacting the pipe opening with the natural seabed surface during filling, utilizing the self-flowing property of the solidified soil to form a solidified soil cover around the wind turbine pile foundation.

[0004] However, existing technologies have the following problems:

[0005] Traditional riprap repair methods can easily create voids in the riprap layer, leading to continuous scouring and structural damage.

[0006] While the method of fully covering and stabilizing soil is effective, it requires a large amount of materials and has high construction costs.

[0007] Therefore, the market needs a repair solution that is structurally robust, has strong erosion resistance, and is economical. Summary of the Invention

[0008] The purpose of this invention is to provide a construction method for a composite scour repair structure of offshore wind power scour fluidized solidified soil-rock slab, which avoids the problem of poor repair effect of traditional rock slab and reduces the high construction cost caused by full-cast solidified soil.

[0009] The objective of this invention is achieved as follows: a construction method for a composite scour repair structure of offshore wind power scour fluidized solidified soil-rockfill, the structure of which includes: a bottom sidewall solidified soil layer covering the bottom and sides of the scour pit; a rockfill filling layer, wherein the bottom sidewall solidified soil layer is combined with the rockfill filling layer from the bottom and sides and fills the cavity of the scour pit; and an upper solidified soil protective layer, wherein the upper solidified soil protective layer covers and seals the opening of the scour pit and completely covers the upper part of the rockfill filling layer.

[0010] The method includes the following steps: S1, filling the bottom sidewall solidified soil layer into the scour pit; S2, filling the riprap filling layer; S3, completely covering the top of the riprap filling layer with a certain thickness of overlying solidified soil protective layer and sealing the opening of the scour pit, wherein the outer part of the overlying solidified soil protective layer is in contact with the seabed surface.

[0011] Furthermore, the solidified soil layer on the bottom sidewall permeates from the bottom and side directions and fills the pores of the riprap filling layer.

[0012] Furthermore, the overlying solidified soil protective layer penetrates downwards under its own weight and fills the pores of the riprap filling layer.

[0013] Furthermore, the filling thickness of the bottom sidewall solidified soil layer is 0.3D, where D is the diameter of the pile foundation.

[0014] Furthermore, the overlying solidified soil protective layer is in the shape of a dome, the diameter of the overlying solidified soil protective layer is 2-3 times the diameter of the pile foundation, and the thickness of the overlying solidified soil protective layer is 0.1D.

[0015] Furthermore, the riprap filling layer is uniformly riprap placed around the pile foundation on the bottom sidewall solidified soil layer until it is flush with the seabed surface.

[0016] Furthermore, before filling, a bottom layer of solidified soil and an overlying solidified soil protective layer are prepared, which are composed of the following components: soil, 22 parts; composite curing agent, 8 parts; water, 20 parts.

[0017] Furthermore, the scour pit involved in this method is roughly in the shape of an inverted frustum, and the structural part formed by the combination of the bottom sidewall solidified soil layer and the riprap filling layer presents an inverted frustum structure that matches the scour pit.

[0018] Furthermore, the method involves a cylindrical pile foundation that is centrally and fixedly inserted into the scour pit and coaxial with the scour pit. The bottom sidewall solidified soil layer, the riprap filling layer, and the overlying solidified soil protective layer surround and closely adhere to the pile foundation.

[0019] Furthermore, the overlying solidified soil protective layer is generally shaped as an upright frustum-shaped cone.

[0020] The beneficial effects of this invention are as follows:

[0021] 1. By using a combination of bottom sidewall solidified soil layer, riprap filling layer and top solidified soil protective layer to form a repair structure, it can better deal with the situation of scour pits around offshore wind power pile foundations. It avoids the shortcomings of traditional riprap protection, such as the easy erosion of pores and the easy washing away of riprap particles, which leads to weak protection effect. It also reduces the high cost caused by full-cast solidified soil.

[0022] 2. The combined repair structure of the present invention has high structural strength and good load-bearing capacity. During construction, the bottom sidewall solidified soil layer penetrates and fills the pores of the riprap filling layer from the bottom and side directions. The bottom sidewall solidified soil layer can also stably support the riprap filling layer. The top solidified soil protective layer penetrates downward under its own weight and fills the pores of the riprap filling layer, thereby forming a sealing layer for the riprap filling layer. This makes the bottom sidewall solidified soil layer, the riprap filling layer and the top solidified soil protective layer a solid whole. The riprap filling layer is covered and sealed by the bottom sidewall solidified soil layer and the top solidified soil protective layer, avoiding the erosion of pores and the easy washing away of riprap particles, which would lead to a weak protective effect. Furthermore, because the outer part of the top solidified soil protective layer is in contact with the seabed surface, the top solidified soil protective layer can better seal the opening of the scour pit, further enhancing the scour resistance. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the completed construction state of the present invention.

[0024] Explanation of reference numerals in the attached drawings: 1-Pile foundation; 2-Underlying sidewall solidified soil layer; 3-Rock filling layer; 4-Overlying solidified soil protective layer. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figure 1 As shown, a composite scour repair structure of fluidized solidified soil-rock slab is proposed for offshore wind power scour. The structure includes:

[0027] The bottom edge wall solidified soil layer 2 completely covers the bottom and sides of the scour pit. The upper end of the bottom edge wall solidified soil layer 2 is flush with the opening of the scour pit. The bottom edge wall solidified soil layer 2 plays a role in preventing edge scouring.

[0028] The riprap filling layer 3, which is composed of several piled stones, is combined with the bottom side wall solidified soil layer 2 from the bottom and side directions to fill the scour pit cavity. The riprap filling layer 3 plays the role of filling and stabilizing the position of the pile foundation 1.

[0029] The upper solidified soil protective layer 4 covers and seals the opening of the scour pit, completely covering the upper part of the riprap filling layer 3. The upper solidified soil protective layer 4 plays the role of preventing scour and fixing the riprap particles of the riprap filling layer 3.

[0030] Among them, the slurry retention rate of the above-mentioned solidified soil layer meets more than 80% under the condition of water flow velocity of 2.5m / s, and the strength of the solidified soil after solidification can withstand long-term wave loads, which can meet the needs of most sea areas in my country.

[0031] The construction process includes the following steps:

[0032] S1. Fill the scour pit with the bottom layer of solidified soil on the sidewalls 2;

[0033] S2, Filling 3, the riprap filling layer 3 is a layer of riprap uniformly placed around the pile foundation 1 on the bottom side wall solidified soil layer 2 until it is flush with the seabed surface. The median particle size of the riprap is 240mm-560mm and the particle size distribution is smooth.

[0034] S3. A certain thickness of overlying solidified soil protective layer 4 is completely covered over the top of the riprap filling layer 3, and the opening of the scour pit is sealed. The outer part of the overlying solidified soil protective layer 4 is attached to the seabed surface.

[0035] The bottom sidewall solidified soil layer 2 permeates and fills the pores of the riprap filling layer 3 from the bottom and side surfaces. This layer also provides stable support for the riprap filling layer 3. Together, they fill the scour pit. The overlying solidified soil protective layer 4, under its own weight, permeates downwards and fills the pores of the riprap filling layer 3, thus forming a sealing layer for the riprap filling layer 3. Simultaneously, because the outer portion of the overlying solidified soil protective layer 4 adheres to the seabed surface, it seals the opening of the scour pit. The overlying solidified soil protective layer 4, the bottom sidewall solidified soil layer 2, and the riprap filling layer 3 combine to form a robust structure that effectively resists the repeated scouring action of seawater.

[0036] As an optimized solution for mechanical performance, the scour pit is roughly shaped like an inverted frustum. The structure formed by the solidified soil layer 2 on the bottom sidewall and the riprap filling layer 3 also presents an inverted frustum shape that matches the scour pit, significantly enhancing the horizontal load-bearing capacity of the central pile foundation 1 (because the wind turbine is mainly subjected to complex and variable horizontal wind loads). Utilizing the excellent impact resistance and tolerance to complex alternating loads of the frustum configuration, the structural strength of the composite scour repair structure is further improved.

[0037] The method involves a cylindrical pile foundation 1, which is centrally and fixedly inserted into the scour pit and coaxial with the scour pit. The bottom sidewall solidified soil layer 2, the riprap filling layer 3, and the overlying solidified soil protective layer 4 surround and closely adhere to the pile foundation 1.

[0038] Furthermore, upon completion of construction, the aforementioned overlying solidified soil protective layer 4 presents an overall structure resembling an upright frustum of a cone. Utilizing the excellent impact resistance of the frustum of a cone configuration, the structural strength of the overlying solidified soil protective layer 4 is further enhanced, thereby consolidating its erosion resistance.

[0039] As a preferred parameter, the filling thickness of the bottom sidewall solidified soil layer 2 is 0.3D, where D is the diameter of the pile foundation 1. The upper solidified soil protective layer 4 is in the shape of a dome, the diameter of the upper solidified soil protective layer 4 is 2-3 times the diameter of the pile foundation 1, and the thickness of the upper solidified soil protective layer 4 is 0.1D.

[0040] Before filling, a bottom sidewall solidified soil layer 2 and an overlying solidified soil protective layer 4 are prepared, which are composed of the following components: soil, 22 parts; composite curing agent, 8 parts; water, 20 parts.

[0041] The composite curing agent is composed of multiple substances, specifically: 14 parts cement; 5 parts water glass; and 1 part calcium chloride.

[0042] The soil used is waste soil from underground engineering projects, with a moisture content of 30.9%, a liquid limit of 41.3%, and a plastic limit of 20.31%.

[0043] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In this invention, it should also be noted that the terms "installation" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, an integrally formed connection, a mechanical connection, or an indirect connection through intermediate connecting parts. The specific meaning of the terms in this utility model can be understood according to the specific circumstances.

[0044] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0045] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A construction method for a composite scour repair structure of offshore wind power-driven fluidized solidified soil-rubble composite scour, characterized in that, The structure involved in this method includes: a bottom sidewall solidified soil layer (2) covering the bottom and sides of the scour pit; a riprap filling layer (3), wherein the bottom sidewall solidified soil layer (2) is combined with the riprap filling layer (3) from the bottom and side directions and fills the cavity of the scour pit; and an upper solidified soil protective layer (4), wherein the upper solidified soil protective layer (4) covers and seals the opening of the scour pit and completely covers the upper part of the riprap filling layer (3); The method includes the following steps: S1, filling the bottom sidewall solidified soil layer (2) into the scour pit; S2, filling the riprap filling layer (3); S3, completely covering the upper part of the riprap filling layer (3) with a certain thickness of overlying solidified soil protective layer (4) and sealing the opening of the scour pit, wherein the outer part of the overlying solidified soil protective layer (4) is in contact with the seabed surface.

2. The construction method of the offshore wind power scour fluidized solidified soil-rock composite scour repair structure according to claim 1, characterized in that, The bottom sidewall solidified soil layer (2) permeates from the bottom and side directions and fills the pores of the riprap filling layer (3).

3. The construction method of the offshore wind power scour fluidized solidified soil-rock composite scour repair structure according to claim 2, characterized in that, The overlying solidified soil protective layer (4) penetrates downwards under its own weight and fills the pores of the riprap filling layer (3).

4. The construction method of the offshore wind power scour fluidized solidified soil-rock composite scour repair structure according to claim 2, characterized in that, The filling thickness of the bottom sidewall solidified soil layer (2) is 0.3D, where D is the diameter of the pile foundation (1).

5. The construction method of the offshore wind power scour fluidized solidified soil-rock composite scour repair structure according to claim 4, characterized in that, The overlying solidified soil protective layer (4) is in the shape of a dome, and the diameter of the overlying solidified soil protective layer (4) is 2-3 times the diameter of the pile foundation (1). The thickness of the overlying solidified soil protective layer (4) is 0.1D.

6. The construction method of the offshore wind power scour fluidized solidified soil-rock composite scour repair structure according to claim 4, characterized in that, The riprap filling layer (3) is formed by uniformly riprapping around the pile foundation (1) on the bottom sidewall solidified soil layer (2) until it is flush with the seabed surface.

7. The construction method of the offshore wind power scour fluidized solidified soil-rock composite scour repair structure according to claim 1, characterized in that, Before filling, a bottom sidewall solidified soil layer (2) and an overlying solidified soil protective layer (4) are prepared, which are composed of the following components: soil, 22 parts; composite solidifying agent, 8 parts; water, 20 parts.

8. The construction method of a composite scour repair structure for offshore wind power scour fluidized solidified soil-rock composite as described in claim 6, characterized in that, The scour pit involved in this method is roughly in the shape of an inverted frustum. The structure formed by the solidified soil layer (2) on the bottom side wall and the riprap filling layer (3) is an inverted frustum that matches the scour pit.

9. The construction method of a composite scour repair structure for offshore wind power scour by solidified soil-rubble composite scour according to claim 8, characterized in that, The pile foundation (1) involved in this method is cylindrical, centrally fixed and inserted into the scour pit, and coaxial with the scour pit. The bottom side wall solidified soil layer (2), the riprap filling layer (3) and the overlying solidified soil protective layer (4) surround and closely adhere to the pile foundation (1).

10. The construction method of a composite scour repair structure for offshore wind power scour fluidized solidified soil-rock composite as described in claim 9, characterized in that, The overlying solidified soil protective layer (4) is generally in the shape of an upright truncated cone.

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