Rock-socketed gravity type fan foundation and mounting method thereof

Abstract

The invention discloses a rock-socketed gravity type fan foundation and an installation method thereof.The fan foundation comprises an upper bearing platform, the upper bearing platform can be selectively arranged to be a triangular box or a quadrilateral box according to the number of high pile legs, a fan tower barrel is installed at the center of the upper bearing platform through a foundation pre-flange, and the high pile legs are arranged at the end corners of the upper bearing platform; a lifting system is arranged on the upper portion of a deck of the upper bearing platform and located near the high pile leg, a pile shoe is arranged at the bottom of the high pile leg, and a rock-socketed pile leg is arranged in the high pile leg. The platform can be used as a rock-socketed operation platform and can also be used as a fan foundation, so that the offshore operation time is greatly shortened; meanwhile, the upper bearing platform cabin is fully utilized for upper ballasting, the mud entering depth of the socketed pile is reduced, and the rock socketed workload is reduced; the pile shoes are arranged at the bottoms of the high pile legs, so that the compression bearing capacity of the platform can be effectively improved; the cone is arranged at the bottom of the rock-socketed pile leg, so that soil breaking and stone breaking can be carried out, drilling operation is facilitated, and rock-socketed efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of marine engineering construction, and in particular to a rock-embedded gravity fan foundation and an installation method thereof. Background Art

[0002] With the continuous development of domestic offshore wind power development, the offshore wind power development area is constantly expanding, and the geological conditions of my country's wind power development sea areas are diverse. The use of conventional offshore wind turbine foundations such as single pile foundations and jacket foundations can no longer fully adapt to the future development of offshore wind power, especially for areas with less surface cover, or even sea areas where the surface is rock foundation. Such sea areas generally use gravity foundations, large-diameter single pile rock-embedded foundations, or jacket rock-embedded foundations. Gravity foundations require large-scale seabed processing work and are generally heavy. Large-diameter single pile rock-embedded foundations generally require a special rock-embedded platform, and the large rock-embedded diameter is prone to collapse, etc., with low work efficiency and high cost. Jacket rock-embedded foundations, the wind power field generally adopts the pile-first method, which requires a special rock-embedded platform to complete the construction of the rock-embedded section, and then the jacket foundation is inserted into the rock-embedded section for grouting consolidation. From the current construction situation, it is difficult to insert the jacket into the rock-embedded section, and the precision control of the rock-embedded section is relatively strict. This process will consume a lot of offshore equipment resources and time, resulting in a significant increase in costs.

[0003] In order to solve the above problems, we proposed a rock-embedded gravity wind turbine foundation and its installation method. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a rock-embedded gravity fan foundation and an installation method thereof. The present invention provides the following technical solutions: A rock-embedded gravity wind turbine foundation comprises an upper pedestal, which can be set as a triangular box or a quadrilateral box according to the number of high pile legs. A wind turbine tower is installed at the center of the upper pedestal through a foundation pre-flange, high pile legs are arranged at the end corners of the upper pedestal, a lifting system for realizing the lifting, lowering and leveling functions of the upper pedestal is arranged on the upper part of the deck of the upper pedestal and near the high pile legs, pile shoes are arranged at the bottom of the high pile legs, and rock-embedded legs are arranged inside the high pile legs.

[0005] Preferably, a bulkhead is provided inside the box body of the upper support platform.

[0006] Preferably, the diameter of the rock-embedded pile leg is smaller than the diameter of the high pile leg, a gear is provided at the bottom of the rock-embedded pile leg, and the height of the rock-embedded pile leg can be set to be 6 to 7 meters above the mud surface or consistent with the top elevation of the high pile leg.

[0007] The present invention also relates to a method for installing a rock-embedded gravity wind turbine foundation, the method comprising the following steps: Step S1: The upper platform is transported as a whole to the offshore construction site, the wide barge transport ship is brought close to the crane ship, and the crane ship is used to lift the platform as a whole to the water surface, and the platform and the crane ship are temporarily cabled; Step S2: After the installation position is determined, the high pile legs are lowered by using the lifting system so that the pile shoes touch the mud; Step S3: using a crane to lift the upper cap to the designed height for rock-embedded operations, temporarily fixing the high pile legs and the upper cap, using the deadweight of the structure to drive the pile shoe into the mud, and ballasting the interior of the upper cap according to the bearing capacity requirements of the rock-embedded operations to make the pile shoe reach the designed depth; Step S4: releasing the temporary fixation of the high pile legs and the upper cap, starting the lifting system for leveling, and then temporarily fixing the high pile legs and the upper cap after leveling; Step S5: releasing the temporary fixation of the rock-embedded pile legs and the high pile legs, hoisting the rock-embedded equipment onto the upper cap by a crane to perform rock-embedded drilling operations on the rock-embedded pile legs, and after drilling the rock-embedded pile legs to the designed depth, performing grouting and consolidation operations on the rock-embedded pile legs and the high pile legs; Step S6: Use the lifting system to lift the upper pedestal to the design elevation of the wind turbine foundation, and perform ballasting according to the design ballasting requirements. After the ballasting is completed, the upper pedestal is leveled. After the leveling is completed, the upper pedestal and the high pile legs are permanently fixed.

[0008] Compared with the prior art, the present invention can achieve the following beneficial effects: 1. The present invention can be used as a rock-embedded operation platform, and after completing the rock-embedded operation, it can also be used as a wind turbine foundation, eliminating an installation process and greatly reducing offshore operation time; 2. The present invention makes full use of the cabin of the upper cap box for upper ballast, uses the upper ballast to resist the pull-out force, reduces the depth of the rock-embedded piles required to be inserted into the mud, and reduces the workload of rock-embedded piles; 3. The present invention can effectively improve the compressive bearing capacity of the platform by arranging pile shoes at the bottom of the high pile legs; 4. The present invention provides a cone at the bottom of the rock-embedded pile leg to break soil and rocks, thereby facilitating drilling operations and improving rock-embedded efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] By reading the detailed description of the preferred embodiment below, various other advantages and benefits will become clear to those of ordinary skill in the art. The accompanying drawings are only used to illustrate the purpose of the preferred embodiment and are not considered to be limitations of the present invention. In the entire drawings, the same reference numerals are used to represent the same components.

[0010] In the attached picture: Figure 1It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the upper platform cabin of the present invention; Figure 3 is a plan view of the rock embedding of the present invention; Figure 4 It is a partial view of the bottom end of the rock-embedded pile leg of the present invention; Figure 5 It is a schematic diagram of wide barge transportation of the present invention; Figure 6 It is a schematic diagram of lowering the wide barge transport pile legs of the present invention; Figure 7 It is a schematic diagram of lifting the upper bearing platform of the barge transportation of the present invention; Figure 8 It is a schematic diagram of rock embedding operation of the present invention; Fig. 9 It is a schematic diagram of narrow barge transportation of the present invention; Fig.10 It is a schematic diagram of lowering pile legs for narrow barge transportation according to the present invention; Fig.11 It is a schematic diagram of lifting the upper support platform of the narrow barge transport of the present invention; Fig.12 It is a schematic diagram of wet towing transportation of the present invention.

[0011] in, Figures 1 to 12 The corresponding relationship between the reference numerals and the components is as follows: 1. Wind turbine tower; 2. Lifting system; 3-Upper pedestal; 4-Foundation pre-flange; 5. High pile legs; 6. Pile shoes; 7. Rock-embedded pile legs; 8. Bulkhead; 9. Water surface; 10. Mud surface; 11. Gear; 12. Rock-embedded equipment; 13. Wide barge transport ship; 14. Narrow barge transport ship; 15. Crane ship. Implementation

[0012] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0013] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0014] Combine the following Figure 1-12 A rock-embedded gravity wind turbine foundation and an installation method thereof according to an embodiment of the present invention are specifically described.

[0015] like Figures 1 to 4 As shown, the upper pedestal 3 of the rock-embedded gravity wind turbine foundation can be configured into a triangular or quadrilateral box according to the number of high pile legs 5. A bulkhead 8 and reinforcing ribs are arranged inside the box of the upper pedestal 3. A foundation pre-flange 4 is arranged at the center of the box of the upper pedestal 3, and is connected to the wind turbine tower 1. At the same time, a reinforcing structure is arranged in the connection area. The size of the cabin is determined according to the ballast capacity, and its main function is to resist the pulling force generated by the wind turbine and ocean hydrology on the structure; high pile legs 5 are arranged at the end corners of the upper pedestal 3, and 3 or 4 high pile legs 5 can be arranged according to the shape of the upper pedestal 3. Pile shoes 6 are arranged at the bottom of the high pile legs 5. The form of the pile shoes 6 can be circular or polygonal, which is used to provide the compressive bearing capacity of the entire platform during the rock-embedded operation; high pile legs 5 The pile length of the leg 5 is determined according to the water depth, the depth of penetration into the mud and the marine hydrological parameters. There is a rock-embedded pile leg 7 inside the high pile leg 5. The diameter of the rock-embedded pile leg 7 is smaller than that of the high pile leg 5. A gear 11 is arranged at the bottom of the rock-embedded pile leg 7 to facilitate drilling operations. The pile length of the rock-embedded pile leg 7 can be set in two forms. One is about 6 to 7 meters higher than the mud surface 10. Shear tendons are arranged in this section to be grouted and connected with the high pile leg 5. The top elevation of the other rock-embedded pile leg 7 can be set to be consistent with the top elevation of the high pile leg 5. Shear tendons are arranged in the part above the bottom mud surface 10 to be grouted and connected with the high pile leg 5. Grouting or welding can be selected between the two piles in the top area. The lifting system 2 is arranged on the deck box near the pile leg to realize the lifting, lowering and leveling functions of the upper cap 3.

[0016] There are three installation methods involved in this embodiment: 1. The first method: wide barge transportation, hoisting installation, see the attached Figures 5 to 8 .

[0017] Step S1: The upper platform 3 is transported as a whole to the offshore construction site, the wide barge transport ship 13 is brought close to the crane ship 15, and the platform is hoisted as a whole to the water surface 9 by the crane ship 15, and the platform and the crane ship 15 are temporarily cabled; Step S2: After the installation position is determined, the high pile leg 5 is lowered by the lifting system 2 so that the pile shoe 6 touches the mud; Step S3: using a crane to lift the upper cap 3 to the designed height for rock-embedded operations, temporarily fixing the high pile legs 5 and the upper cap 3, using the deadweight of the structure to drive the pile shoe 6 into the mud, and ballasting the interior of the upper cap 3 according to the bearing capacity requirements of the rock-embedded operations, so that the pile shoe 6 reaches the designed depth; Step S4: releasing the temporary fixation of the high pile legs 5 and the upper platform 3, starting the lifting system 2 for leveling, and temporarily fixing the high pile legs 5 and the upper platform 3 after leveling; Step S5: release the temporary fixation of the rock-embedded pile leg 7 and the high pile leg 5, use a crane to hoist the rock-embedded equipment 12 onto the upper pedestal 3 to perform rock-embedded drilling operations on the rock-embedded pile leg 7, and after drilling the rock-embedded pile leg 7 to the designed depth, perform grouting and consolidation operations on the rock-embedded pile leg 7 and the high pile leg 5.

[0018] Step S6: Use the lifting system 2 to lift the upper pedestal 3 to the design elevation of the wind turbine foundation, and perform ballasting according to the design ballasting requirements. After the ballasting is completed, the upper pedestal 3 is leveled. After the leveling is completed, the upper pedestal 3 and the high pile legs 5 are permanently fixed.

[0019] 2. The second method: narrow barge transportation and self-installation, see the attached Figures 9-11 .

[0020] Step S1: The upper platform 3 is transported as a whole to the offshore construction site, and the narrow barge transport ship 14 is anchored at a fixed position; Step S2: After the installation position is determined, a narrow ship transport vessel 14 is used as a carrier, and the high pile legs 5 are lowered by the lifting system 2 so that the pile shoes 6 touch the mud; Step S3: using the lifting system 2 to lift the upper cap 3 to the designed height for rock embedding operation, temporarily fix the high pile legs 5 and the upper cap 3, use the deadweight of the structure to make the pile shoe 6 sink into the mud, and ballast the interior of the upper cap 3 according to the bearing capacity requirements of the rock embedding operation, so that the pile shoe 6 reaches the designed depth; Step S4: releasing the temporary fixation of the high pile legs 5 and the upper platform 3, starting the lifting system 2 for leveling, and temporarily fixing the high pile legs 5 and the upper platform 3 after leveling; Step S5: release the temporary fixation of the rock-embedded pile leg 7 and the high pile leg 5, use a crane to hoist the rock-embedded equipment 12 onto the upper pedestal 3 to perform rock-embedded drilling operations on the rock-embedded pile leg 7, and after drilling the rock-embedded pile leg 7 to the designed depth, perform grouting and consolidation operations on the rock-embedded pile leg 7 and the high pile leg 5.

[0021] Step S6: Use the lifting system 2 to lift the upper pedestal 3 to the design elevation of the wind turbine foundation, and perform ballasting according to the design ballasting requirements. After the ballasting is completed, the upper pedestal 3 is leveled. After the leveling is completed, the upper pedestal 3 and the high pile legs 5 are permanently fixed.

[0022] The third method: wet towing transportation and self-installation, see attached Fig.12 .

[0023] Step S1: wet-drag the upper platform 3 as a whole to the offshore construction site, and use the construction ship with a cable to control the position of the entire platform; Step S2: After the installation position is determined, the upper platform 3 uses its own buoyancy as a carrier and uses the lifting system 2 to lower the high pile legs 5 so that the pile shoes 6 touch the mud; Step S3: using the lifting system 2 to lift the upper cap 3 to the designed height for rock-embedded operation, temporarily fix the high pile legs 5 and the upper cap 3, use the deadweight of the structure to make the pile shoe 6 sink into the mud, and ballast the interior of the upper cap 3 according to the bearing capacity requirements of the rock-embedded operation, so that the pile shoe 6 reaches the designed depth; Step S4: releasing the temporary fixation of the high pile legs 5 and the upper platform 3, starting the lifting system 2 for leveling, and temporarily fixing the high pile legs 5 and the upper platform 3 after leveling; Step S5: release the temporary fixation of the rock-embedded pile leg 7 and the high pile leg 5, use a crane to hoist the rock-embedded equipment 12 onto the upper pedestal 3 to perform rock-embedded drilling operations on the rock-embedded pile leg 7, and after drilling the rock-embedded pile leg 7 to the designed depth, perform grouting and consolidation operations on the rock-embedded pile leg 7 and the high pile leg 5.

[0024] Step S6: Use the lifting system 2 to lift the upper pedestal 3 to the design elevation of the wind turbine foundation, and perform ballasting according to the design ballasting requirements. After the ballasting is completed, the upper pedestal 3 is leveled. After the leveling is completed, the upper pedestal 3 and the high pile legs 5 are permanently fixed.

[0025] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

Claims

1. A rock-embedded gravity wind turbine foundation, comprising an upper pedestal (3), characterized in that: The upper pedestal (3) can be configured as a triangular box or a quadrilateral box according to the number of high pile legs (5); a wind turbine tower (1) is mounted at the center of the upper pedestal (3) via a foundation pre-flange (4); high pile legs (5) are provided at the end corners of the upper pedestal (3); a lifting system (2) for realizing the lifting, lowering and leveling functions of the upper pedestal (3) is provided at the upper part of the deck of the upper pedestal (3) and near the high pile legs (5); a pile shoe (6) is provided at the bottom of the high pile legs (5); and a rock-embedded pile leg (7) is provided inside the high pile legs (5).

2. The rock-embedded gravity wind turbine foundation according to claim 1, characterized in that: A bulkhead (8) is provided inside the box body of the upper support platform (3).

3. The rock-embedded gravity wind turbine foundation according to claim 1, characterized in that: The diameter of the rock-embedded pile leg (7) is smaller than the diameter of the high pile leg (5), a cone (11) is provided at the bottom of the rock-embedded pile leg (7), and the height of the rock-embedded pile leg (7) can be set to be 6 to 7 meters higher than the mud surface (10) or to be consistent with the top elevation of the high pile leg (5).

4. A method for installing a rock-embedded gravity wind turbine foundation, using a rock-embedded gravity wind turbine foundation as claimed in claims 1 to 3, characterized in that: The method for installing a rock-embedded gravity wind turbine foundation comprises the following steps: Step S1: The upper support platform (3) is transported as a whole to the offshore construction site, the wide barge transport ship (13) is brought close to the crane ship (15), and the platform is hoisted as a whole to the water surface (9) by the crane ship (15), and the platform and the crane ship (15) are temporarily cabled; Step S2: After the installation position is determined, the high pile leg (5) is lowered by using the lifting system (2) so that the pile shoe (6) touches the mud; Step S3: using a crane to lift the upper cap (3) to the designed height for rock embedding operations, temporarily fixing the high pile legs (5) and the upper cap (3), using the deadweight of the structure to drive the pile shoe (6) into the mud, and applying ballasting to the interior of the upper cap (3) according to the bearing capacity requirements for rock embedding operations, so that the pile shoe (6) reaches the designed depth; Step S4: releasing the temporary fixation of the high pile legs (5) and the upper pedestal (3), starting the lifting system (2) for leveling, and then temporarily fixing the high pile legs (5) and the upper pedestal (3) after leveling; Step S5: releasing the temporary fixation of the rock-embedded pile leg (7) and the high pile leg (5), using a crane to hoist the rock-embedded equipment (12) onto the upper pedestal (3) to perform rock-embedded drilling operations on the rock-embedded pile leg (7); after the rock-embedded pile leg (7) is drilled to a designed depth, grouting and consolidation operations are performed on the rock-embedded pile leg (7) and the high pile leg (5); Step S6: using the lifting system (2) to lift the upper pedestal (3) to the design elevation of the wind turbine foundation, and applying ballasting in accordance with the design ballasting requirements. After the ballasting is completed, the upper pedestal (3) is leveled. After the leveling is completed, the upper pedestal (3) and the high pile legs (5) are permanently fixed.

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