Underwater pile foundation double-steel casing structure and installation process

Abstract

The application discloses a kind of underwater pile foundation double-steel casing structures and installation process, belong to marine engineering pile foundation construction technical field.The structure includes outer casing assembly and inner casing assembly, inner casing assembly is set to the inside of outer casing assembly, and annular operation space is formed between inner casing assembly and outer casing assembly.The application is locked and sealed assembly by being set, realize the quick detachable locking and sealing connection of inner casing assembly and outer casing assembly, ensure the integrity of annular operation space;By internal guiding system, accurately guide and centering during the lowering process of inner casing assembly are effectively carried out, and collision and deviation in the installation process are avoided.The structure can significantly improve the efficiency, safety and accuracy of underwater pile foundation construction, reduce construction cost, optimize the installation and sealing operation of double-steel casing.

Description

Technical Field

[0001] This invention relates to the field of marine engineering pile foundation construction technology, and in particular to an underwater pile foundation double steel casing structure and its installation process. Background Technology

[0002] In marine engineering construction, underwater pile foundation construction is a crucial foundational step. To ensure the construction quality and safety of the pile foundation, a double-layer steel casing structure is often used. This involves installing an outer casing before pile driving, and then lowering an inner casing inside the outer casing to form a ring-shaped working space. This ring-shaped working space can be used for concrete pouring, cleaning the pile hole, maintaining watertightness, and providing a relatively stable working environment. However, the existing double-steel casing structure presents many challenges and shortcomings in practical applications.

[0003] Firstly, during the lowering of the inner casing into the outer casing, the complex underwater environment, low visibility, and limited operating space present a significant challenge to the precise guidance and centering of the inner casing. Existing methods typically rely on manual experience and simple guiding devices, which can easily lead to collisions between the inner and outer casings. This can not only damage the casing structure and affect its service life but also cause jamming or deviation from the center during lowering, severely impacting the accuracy and progress of subsequent pile foundation construction. It may even require substantial time for correction or rework, significantly increasing construction costs and risks.

[0004] Secondly, the connection and sealing between the inner and outer casings are crucial to ensuring the watertightness of the annular working space. Traditional connection methods may involve bolting or welding, which are complex and time-consuming in underwater or humid environments, and it is difficult to guarantee the reliability of the connection and the tightness of the seal. This inefficiency is particularly pronounced in construction scenarios requiring frequent disassembly and reinstallation. If the seal is not tight, external water may seep into the annular working space, leading to serious quality problems such as concrete segregation and pile hole collapse, and may even affect the bearing capacity and structural stability of the entire pile foundation. Furthermore, to maintain the water level balance in the annular working space or to carry out drainage operations, dedicated drainage and water injection channels are usually required, but existing designs often fail to consider this, resulting in operational inconvenience and increased construction difficulty and time.

[0005] In view of the shortcomings of the existing technology, there is an urgent need for an innovative double steel casing structure that can improve the accuracy of lowering the inner casing, achieve rapid and reliable locking and sealing, and optimize the operation of the annular working space, so as to improve the overall efficiency and quality of underwater pile foundation construction. Summary of the Invention

[0006] To address the aforementioned problems, this invention proposes an underwater pile foundation double steel casing structure and installation process, which more accurately solves the problems raised in the background art.

[0007] This invention is achieved through the following technical solution: This invention proposes an underwater pile foundation double steel casing structure and installation process, including an outer casing assembly and an inner casing assembly. The inner casing assembly is disposed inside the outer casing assembly, and an annular working space is formed between the inner casing assembly and the outer casing assembly. The structure also includes: a locking and sealing assembly disposed at the upper end of the outer casing assembly for detachably locking and sealing the inner casing assembly to the outer casing assembly; and an internal guiding system fixedly connected to the inner wall of the outer casing assembly for guiding and centering the inner casing assembly during the process of lowering the inner casing assembly into the outer casing assembly. The outer casing assembly is equipped with auxiliary functional interfaces, including an annular space drainage and water injection valve port that penetrates the casing wall of the outer casing assembly and communicates with the annular working space.

[0008] Preferably, the top of the outer casing assembly is fixedly connected to an outer casing top connecting flange, and the top of the inner casing assembly is fixedly connected to an inner casing top connecting flange; the locking and sealing assembly includes radial locking hydraulic cylinders evenly distributed along the circumferential direction of the outer casing top connecting flange, and the piston rod of the radial locking hydraulic cylinder is connected to a locking pin; the inner casing top connecting flange is provided with a locking pin positioning hole that mates with the locking pin; the radial locking hydraulic cylinder drives the locking pin to extend radially to insert into the locking pin positioning hole, thereby achieving locking.

[0009] Preferably, the locking and sealing assembly also includes a main sealing ring disposed on the upper surface of the top connecting flange of the outer casing. When the top connecting flange of the outer casing and the top connecting flange of the inner casing are locked, the main sealing ring is pressed between the two to form a seal.

[0010] Preferably, the locking and sealing assembly also includes a self-tightening seal ring, which is disposed in an annular groove on the upper surface of the connecting flange at the top of the outer casing and located inside the main seal ring.

[0011] Preferably, the internal guidance system includes an upper tapered guide block fixed to the upper part of the inner wall of the outer casing assembly and a lower roller centering bracket fixed to the lower part of the inner wall of the outer casing assembly.

[0012] Preferably, the upper conical guide blocks are evenly distributed along the inner wall of the outer casing assembly, and the inner surface of the upper conical guide blocks facing the center of the outer casing assembly is a downwardly inclined guide slope.

[0013] Preferably, the lower roller centering brackets are evenly distributed along the inner wall of the outer casing assembly, and each lower roller centering bracket is rotatably connected to a roller via a pin, with the outer edge of the roller making rolling contact with the outer wall of the inner casing assembly.

[0014] Preferably, the locking and sealing assembly also includes an annular hydraulic manifold block fixed above the connecting flange at the top of the outer casing. The radial locking hydraulic cylinders are installed on the inner side of the annular hydraulic manifold block in the circumferential direction. The annular hydraulic manifold block is provided with oil passages that distribute hydraulic oil to each radial locking hydraulic cylinder.

[0015] Preferably, the outer casing assembly includes an outer casing body, the bottom of which is connected to an outer casing cutting edge, and an outer casing reinforcing ring for enhancing structural rigidity is fixedly welded to the outer wall of the outer casing body.

[0016] Preferably, an installation process for an underwater pile foundation double steel casing structure is also provided, comprising the following steps: S1. Use lifting equipment to hoist the outer casing assembly above the pile hole, slowly lower it to the design elevation, adjust the verticality of the outer casing through the guide frame or positioning device, fix the bottom cutting edge of the outer casing to the bottom rock or soil layer of the pile foundation to ensure stability, weld the outer casing reinforcing ring and check the weld quality, and install the auxiliary functional interface. S2. Weld upper tapered guide blocks evenly distributed around the upper part of the inner wall of the outer casing, with the guide slope facing the center of the casing. Install lower roller centering brackets evenly distributed around the lower part of the inner wall of the outer casing, connect the rollers through pins, adjust the gap between the rollers and the outer wall of the inner casing, simulate the lowering process of the inner casing, and check the cooperative working performance of the guide blocks and rollers. S3. Use a special lifting tool to lift the inner casing assembly horizontally, align it with the top connecting flange of the outer casing, and slowly lower it. The bottom of the inner casing contacts the upper conical guide block, and the initial centering is achieved through the guide slope. As the inner casing continues to be lowered, the rollers of the lower roller centering bracket roll into contact with the outer wall of the inner casing, automatically adjusting the coaxiality. S4. Fix the annular hydraulic oil circuit block above the top flange of the outer casing, connect the radial locking hydraulic cylinder and test the oil circuit sealing performance. Install the main sealing ring and the self-tightening sealing ring into the annular groove of the top flange of the outer casing in sequence. Start the hydraulic pump station, drive the locking pin to extend radially and insert it into the locking pin positioning hole of the top flange of the inner casing. The locking force is ≥ the design value. Inject water into the annular space and pressurize it through the drain and water injection valve ports. S5. Drain the water accumulated in the annular space or inject mud through the drainage and injection valves, close the valves, and re-pressurize to test the sealing performance. Confirm that there is no leakage. Use a laser scanner or ultrasonic thickness gauge to check the coaxiality, verticality and wall thickness of the double steel casing. The deviation must meet the design specifications. Submit the installation record, test report and acceptance documents to complete the construction and delivery.

[0017] Compared with the prior art, the present invention provides an underwater pile foundation double steel casing structure and installation process, which has the following beneficial effects: 1. This invention achieves a quick and detachable locking and sealing connection between the inner and outer casing assemblies by setting up a locking and sealing assembly. A radial locking hydraulic cylinder drives the locking pin to insert into the locking pin positioning hole, making operation simple and rapid. Furthermore, the main sealing ring and the self-tightening sealing ring work together to ensure the tightness and watertightness of the connection, significantly improving the installation and disassembly efficiency of the double steel casing, reducing the complexity and risk of underwater operations, and avoiding the time-consuming and uncertainties of traditional connection methods.

[0018] 2. This invention effectively solves the guiding and centering problems during the lowering of the inner casing by setting up an internal guiding system. The upper conical guide block provides initial flexible guidance and avoids initial collisions; the rollers on the lower roller centering bracket roll in contact with the outer wall of the inner casing, achieving precise centering and smooth lowering with low friction. This effectively prevents jamming, collisions, or eccentricity between the inner and outer casings, significantly improving the accuracy and safety of lowering and reducing potential structural damage and rework.

[0019] 3. This invention achieves a systematic and integrated functional design by integrating a ring-shaped hydraulic manifold block and a radial locking hydraulic cylinder into the locking and sealing assembly, and by setting auxiliary functional interfaces such as annular space drainage and water injection valves on the outer casing assembly. The integration of the hydraulic manifold block simplifies the layout of the hydraulic system and improves the convenience and reliability of operation; the drainage and water injection valves facilitate the adjustment of working conditions in the annular working space, such as draining water before concrete pouring to ensure a dry working environment, or injecting water during specific processes to maintain internal and external water pressure balance, thereby improving the flexibility and efficiency of the construction process and further ensuring construction quality. Attached Figure Description

[0020] Figure 1 This is a first perspective view of a three-dimensional structure according to an embodiment of the present invention; Figure 2 This is a perspective sectional view of one embodiment of the present invention; Figure 3 This is a three-dimensional exploded view of an embodiment of the present invention; Figure 4 This is a cross-sectional view of a structure according to an embodiment of the present invention; Figure 5 This is a front view of the structure of one embodiment of the present invention; Figure 6 This is a top view of a structure according to an embodiment of the present invention; Figure 7 This is a second perspective view of a three-dimensional structure according to an embodiment of the present invention; Figure 8 This is a cross-sectional view of the connection structure between the outer casing and the top connecting flange of the inner casing in one embodiment of the present invention.

[0021] Component numbering list in the diagram: 1. Outer casing assembly; 11. Outer casing body; 12. Outer casing reinforcing ring; 13. Outer casing cutting edge; 14. Outer casing top connecting flange; 2. Inner casing assembly; 21. Inner casing body; 22. Inner casing top connecting flange; 23. Locking pin positioning hole; 3. Locking and sealing assembly; 31. Annular hydraulic manifold block; 32. Radial locking hydraulic cylinder; 33. Locking pin; 34. Main sealing ring; 35. Self-tightening sealing ring; 4. Internal guiding system; 41. Upper conical guide block; 42. Lower roller centering bracket; 5. Auxiliary functional interface; 51. Annular space drainage and water injection valve port. Detailed Implementation

[0022] The invention will now be further described with reference to the accompanying drawings.

[0023] To achieve a quick and reliable connection and seal between the inner casing assembly 2 and the outer casing assembly 1, this structure includes a locking and sealing assembly 3. This locking and sealing assembly 3 is located at the upper end of the outer casing assembly 1. An outer casing top connecting flange 14 is fixedly connected to the top of the outer casing assembly 1, and an inner casing top connecting flange 22 is fixedly connected to the top of the inner casing assembly 2. The locking and sealing assembly 3 includes multiple radially locking hydraulic cylinders 32 evenly distributed along the circumference of the outer casing top connecting flange 14. Each radially locking hydraulic cylinder 32 has a locking pin 33 connected to the piston rod end. Correspondingly, a locking pin positioning hole 23 is provided on the inner casing top connecting flange 22 to mate with the locking pin 33. After the inner casing assembly 2 is lowered into place, the radial locking hydraulic cylinder 32 drives the locking pin 33 to extend radially and insert into the locking pin positioning hole 23 on the connecting flange 22 at the top of the inner casing, thereby reliably locking the inner casing assembly 2 onto the outer casing assembly 1.

[0024] To ensure the watertightness of the annular working space, the locking and sealing assembly 3 also includes a main sealing ring 34 and a self-tightening sealing ring 35. The main sealing ring 34 is disposed on the upper surface of the outer casing top connecting flange 14. When the outer casing top connecting flange 14 and the inner casing top connecting flange 22 are locked together, the main sealing ring 34 is pressed between them, forming the first seal. The self-tightening sealing ring 35 is disposed in the annular groove on the upper surface of the outer casing top connecting flange 14 and is located inside the main sealing ring 34. The self-tightening sealing ring 35 utilizes the self-tightening characteristic of the internal medium pressure to further enhance the sealing effect and ensure the watertightness of the annular working space. In addition, the locking and sealing assembly 3 also includes an annular hydraulic manifold block 31 fixed above the outer casing top connecting flange 14, and a radial locking hydraulic cylinder 32 is installed circumferentially inside the annular hydraulic manifold block 31. The annular hydraulic manifold block 31 has an internal oil passage that distributes hydraulic oil to each radial locking hydraulic cylinder 32, realizing the integration of the hydraulic system and facilitating overall control.

[0025] To ensure precise guidance and centering of the inner casing assembly 2 during its lowering process, an internal guiding system 4 is provided, which is fixedly connected to the inner wall of the outer casing assembly 1. The internal guiding system 4 includes an upper conical guide block 41 fixed to the upper part of the inner wall of the outer casing assembly 1 and a lower roller centering bracket 42 fixed to the lower part of the inner wall of the outer casing assembly 1. The upper conical guide blocks 41 are evenly distributed circumferentially along the inner wall of the outer casing assembly 1, and their inner surfaces facing the center of the outer casing assembly 1 are downwardly inclined guide slopes. When the inner casing assembly 2 begins to lower, its bottom edge will first contact these conical guide slopes. Through the force of the slopes, the inner casing assembly 2 is initially guided towards the center position, effectively avoiding initial collisions with the inner wall of the outer casing assembly 1. The lower roller centering brackets 42 are also evenly distributed circumferentially along the inner wall of the outer casing assembly 1, and each lower roller centering bracket 42 is rotatably connected to a roller via a pin. As the inner casing assembly 2 is lowered further, its outer wall rolls into contact with the outer edges of these rollers. The low friction characteristics of the rollers ensure that the inner casing assembly 2 can descend smoothly and accurately along the central axis until it finally reaches its final position, achieving precise centering and reducing frictional resistance.

[0026] The outer casing assembly 1 consists of an outer casing body 11, with an outer casing cutting edge 13 connected to its bottom to assist the outer casing assembly 1 in smoothly settling into the soil layer. Multiple outer casing reinforcing rings 12 are fixedly welded to the outer wall of the outer casing body 11. These reinforcing rings 12 significantly enhance the structural rigidity and deformation resistance of the outer casing assembly 1, especially in complex underwater stress environments, and can effectively resist external pressure and construction loads.

[0027] In addition, the outer casing assembly 1 is also equipped with an auxiliary functional interface 5, including an annular space drainage and water injection valve port 51 that penetrates the casing wall of the outer casing assembly 1 and communicates with the annular working space. This valve port 51 facilitates water level control inside the annular working space, such as draining accumulated water when a dry working environment is required, or injecting water when water pressure balance is required, thereby improving the flexibility and safety of construction.

[0028] Finally, it should be noted that the basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification, and therefore remain within the spirit and scope of the exemplary embodiments of this specification. Furthermore, this specification uses specific terms to describe embodiments of this specification. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined. Moreover, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods of this specification.

[0029] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An underwater pile foundation double steel casing structure and installation process, comprising an outer casing assembly (1) and an inner casing assembly (2), wherein the inner casing assembly (2) is disposed inside the outer casing assembly (1), and an annular working space is formed between the inner casing assembly (2) and the outer casing assembly (1), characterized in that, The structure also includes: A locking and sealing assembly (3) is disposed at the upper end of the outer casing assembly (1) for detachably locking and sealing the inner casing assembly (2) to the outer casing assembly (1); and An internal guiding system (4) is fixedly connected to the inner wall of the outer casing assembly (1) and is used to guide and center the inner casing assembly (2) during the process of the inner casing assembly (2) being lowered into the outer casing assembly (1); The outer casing assembly (1) is provided with an auxiliary functional interface (5), which includes an annular space drainage and water injection valve port (51) that penetrates the wall of the outer casing assembly (1) and communicates with the annular working space.

2. The underwater pile foundation double steel casing structure according to claim 1, characterized in that, The top of the outer casing assembly (1) is fixedly connected to the top of the outer casing top connecting flange (14), and the top of the inner casing assembly (2) is fixedly connected to the top of the inner casing top connecting flange (22). The locking and sealing assembly (3) includes radial locking hydraulic cylinders (32) evenly distributed along the circumferential direction of the connecting flange (14) at the top of the outer casing, and the piston rod of the radial locking hydraulic cylinder (32) is connected to a locking pin (33). The inner sleeve top connecting flange (22) is provided with a locking pin positioning hole (23) that cooperates with the locking pin (33). The radial locking hydraulic cylinder (32) drives the locking pin (33) to extend radially and insert into the locking pin positioning hole (23), thereby achieving locking.

3. The underwater pile foundation double steel casing structure according to claim 2, characterized in that, The locking and sealing assembly (3) also includes a main sealing ring (34) disposed on the upper surface of the top connecting flange (14) of the outer casing. When the top connecting flange (14) of the outer casing and the top connecting flange (22) of the inner casing are locked, the main sealing ring (34) is pressed between the two to form a seal.

4. The underwater pile foundation double steel casing structure according to claim 3, characterized in that, The locking and sealing assembly (3) also includes a self-tightening sealing ring (35), which is disposed in the annular groove on the upper surface of the connecting flange (14) at the top of the outer casing and is located inside the main sealing ring (34).

5. The underwater pile foundation double steel casing structure according to claim 1, characterized in that, The internal guiding system (4) includes an upper conical guide block (41) fixed to the upper part of the inner wall of the outer casing assembly (1) and a lower roller centering bracket (42) fixed to the lower part of the inner wall of the outer casing assembly (1).

6. The underwater pile foundation double steel casing structure according to claim 5, characterized in that, The upper conical guide block (41) is evenly distributed along the inner wall of the outer casing assembly (1), and the inner surface of the upper conical guide block (41) facing the center of the outer casing assembly (1) is a downwardly inclined guide slope.

7. The underwater pile foundation double steel casing structure according to claim 5, characterized in that, The lower roller centering bracket (42) is evenly distributed along the inner wall of the outer casing assembly (1), and each lower roller centering bracket (42) is rotatably connected to a roller by a pin, and the outer edge of the roller is in rolling contact with the outer wall of the inner casing assembly (2).

8. The underwater pile foundation double steel casing structure according to claim 2, characterized in that, The locking and sealing assembly (3) also includes an annular hydraulic manifold block (31) fixed above the connecting flange (14) at the top of the outer casing. The radial locking hydraulic cylinder (32) is installed on the inner side of the annular hydraulic manifold block (31) along the circumferential direction. The annular hydraulic manifold block (31) is provided with an oil passage that distributes hydraulic oil to each of the radial locking hydraulic cylinders (32).

9. The underwater pile foundation double steel casing structure according to claim 1, characterized in that, The outer casing assembly (1) includes an outer casing body (11), the bottom of which is connected to an outer casing cutting edge (13), and the outer casing body (11) is fixedly welded with an outer casing reinforcing ring (12) for enhancing structural rigidity.

10. The installation process of an underwater pile foundation double steel casing structure according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Use lifting equipment to hoist the outer casing assembly (1) above the pile hole, slowly lower it to the design elevation, adjust the verticality of the outer casing through the guide frame or positioning device, fix the bottom cutting edge (13) of the outer casing to the bottom rock or soil layer of the pile foundation to ensure stability, weld the outer casing reinforcing ring (12) and check the weld quality, and install the auxiliary functional interface (5). S2. Weld upper tapered guide blocks (41) evenly around the upper part of the inner wall of the outer casing, with the guide slope facing the center of the casing. Install lower roller centering brackets (42) evenly around the lower part of the inner wall of the outer casing. Connect the rollers with pins and adjust the gap between the rollers and the outer wall of the inner casing to simulate the lowering process of the inner casing and check the cooperative working performance of the guide blocks and rollers. S3. Use a special lifting tool to lift the inner casing assembly (2) horizontally, align it with the top connecting flange (14) of the outer casing and slowly lower it. The bottom of the inner casing contacts the upper conical guide block (41), and the initial centering is achieved through the guide slope. When the inner casing continues to be lowered, the rollers of the lower roller centering bracket (42) roll in contact with the outer wall of the inner casing, and automatically adjust the coaxiality. S4. Fix the annular hydraulic oil circuit block (31) above the top flange of the outer casing, connect the radial locking hydraulic cylinder (32) and test the oil circuit sealing performance. Install the main sealing ring (34) and the self-tightening sealing ring (35) in sequence into the annular groove of the top flange of the outer casing. Start the hydraulic pump station, drive the locking pin (33) to extend radially and insert into the locking pin positioning hole (23) of the top flange of the inner casing. The locking force is ≥ the design value. Inject water into the annular space and pressurize it through the drain and water injection valve port (51). S5. Drain the water in the annular space or inject mud through the drainage and water injection valve (51), close the valve (51), pressurize again to test the sealing performance, confirm that there is no leakage, use a laser scanner or ultrasonic thickness gauge to check the coaxiality, verticality and wall thickness of the double steel casing, the deviation must meet the design specifications, submit the installation record, test report and acceptance documents, and complete the construction and delivery.

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