A pile foundation caisson modular assembly artificial island marine structure and a construction method thereof

Abstract

The application discloses a pile foundation caisson modular assembly artificial island marine structure and a construction method thereof. The marine structure comprises caisson units, foundation piles and rigid connecting rings. The caisson units are continuously spliced to form an enclosed structure. The cross section of the caisson unit is a regular hexagonal structure. A preset joint is arranged between adjacent caisson units, and a flexible water stop structure is arranged on the butt joint surface of the caisson units. The caisson unit is matched with the foundation pile through a pile hole. The rigid connecting ring is clamped on the inside and outside of the enclosed structure. The marine structure takes the caisson unit with a regular hexagonal cross section as a modular unit, cooperates with the flexible water stop structure, the foundation pile guide, the rigid connecting structure and the anchor tension system, has a short construction period, good sealing performance and structural adaptability between the caisson units, effectively improves the water stop effect and the settlement stability of the enclosed structure, and has the overall structural rigidity while allowing the joint to slightly deform. The construction method is matched with the marine structure, and the implementability of the overall construction is improved.

Description

Technical Field

[0001] This invention relates to the field of artificial island engineering technology, specifically to an artificial island marine structure with modular assembly of pile foundation caissons and its construction method. Background Technology

[0002] Artificial islands are widely used in land reclamation, oil drilling and other technical fields. Existing artificial island builders construct artificial islands by building cofferdams, constructing sloping dikes by dumping rocks, or inserting large-diameter steel cylinders to form flat-bottomed artificial islands.

[0003] In traditional schemes, in order to ensure the stability of the enclosed boundary of the cofferdam or sloping breakwater, it is often necessary to drive the structure to a deeper bearing layer, or to carry out a large amount of riprap filling, revetment block installation and temporary enclosure construction on the offshore side in advance, resulting in a large amount of offshore operations, long construction period, high construction risk and high cost. Furthermore, while prefabricating and assembling caissons or cofferdams in sections using large-diameter steel cylinders or concrete well bodies, and constructing strip-shaped structures using continuous caisson structures, can improve the degree of component factory production and construction efficiency, the following problems still exist in large-scale marine enclosure applications: First, the structural connection construction and methods between individual caissons have not yet been well developed, thus affecting the integrity and water-stopping performance of the structure; Second, there are settlement position errors among the individual caissons within the structure, causing the enclosure to fail to be assembled and closed, and even causing settlement failure due to compression and jamming during the sinking of some individual caissons; Third, it is difficult to balance assembly accuracy and structural force transmission between adjacent assembled individual caissons, resulting in insufficient overall structural rigidity and wind and wave resistance. Meanwhile, in traditional artificial island construction, the cofferdam structure, land reclamation, vacuum preloading, and outer protection construction are mostly separate construction systems, making it difficult to form a boundary structure with high water-stopping, high stability, and adaptability to synchronous settlement, and also making it difficult to provide reliable conditions for subsequent land-based outer protection construction. Therefore, it is necessary to propose a new modular assembly method for artificial island marine structures based on pile foundation caissons and its construction method, so as to achieve rapid assembly, reliable water stoppage, overall stability, and synchronous settlement of the enclosed structure, and provide stable boundary conditions for subsequent land reclamation, foundation treatment and external protection construction. Summary of the Invention

[0004] The purpose of this invention is to overcome the deficiencies of the prior art and provide a modular assembly of pile foundation caissons for artificial island marine structures and their construction method, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: In the first aspect, a modular assembly of pile-foundation caissons for artificial island marine engineering structures is disclosed, including caisson units, foundation piles, and rigid connecting rings; the caisson unit has a regular hexagonal cross-section, and several caisson units are continuously spliced ​​along the same assembly line to form an enclosed structure; there are pre-set joints between adjacent caisson units, and flexible water-stop structures are provided on the mating surfaces of the two units to form a squeeze water-stop to seal the joints when adjacent caisson units are spliced; multiple pile holes are evenly arranged on the caisson unit, and the pile holes are fitted with the foundation piles with gaps to position and guide the settlement of the caisson unit; the rigid connecting ring is fitted by the inner and outer sides of the enclosed structure to assemble all caisson units into a single load-bearing marine foundation structure.

[0006] In one possible embodiment, the rigid connecting ring is formed by sequentially connecting several rigid connecting structures to form a loop structure. The rigid connecting structure includes an outer connecting beam and an inner connecting beam. The outer connecting beam and the inner connecting beam respectively limit the edges and corners of the outer and inner sides of the caisson unit. Both include a connecting beam and a limiting part. The limiting part extends inward from the inner side of the connecting beam to form a sawtooth structure. The sawtooth structure is adapted to the edges and corners of the caisson unit.

[0007] In one possible embodiment, the flexible water-stopping structure is a rubber water-stop strip, which is pre-embedded on the mating surface of the caisson unit, with its sealing end extending from the mating surface of the caisson unit and being squeezed to adapt to the joint.

[0008] In one possible embodiment, the sealing end of the rubber waterstop strip is a deformable ring with an outer diameter of D and a preset sealing range of 0.38D to 0.6D.

[0009] In one possible embodiment, a wave-blocking assembly structure is also included. The wave-blocking assembly structure is set on top of the marine foundation structure and is formed by continuously splicing and enclosing several wave-blocking units. The wave-blocking units are arranged along the outer edge of the upper end of the caisson unit and have positioning holes. The positioning holes cooperate with the foundation piles directly below them to use the foundation piles of the marine foundation structure for positioning.

[0010] In one possible embodiment, the marine foundation structure is equipped with an anchoring system, one end of which is connected to the caisson unit and the other end is anchored to the landside foundation of the marine foundation structure to apply active preload.

[0011] In one possible embodiment, the upper end of the caisson unit is provided with a plug-in structure, and the lower end is provided with an embedding structure adapted to the plug-in structure for plug-in connection of caisson units in adjacent layers.

[0012] Secondly, a construction method for an artificial island marine structure is disclosed, including the following steps and contents: S1. Batch prefabrication of caisson units, assembling the bottom caisson units with the foundation piles, and pre-fixing the foundation piles into their pile holes; S2. Layered construction of the first caisson module; the caisson module includes foundation piles and multi-layer caisson units connected in series; after the bottom caisson unit is hoisted to the predetermined settlement coordinate and the initial settlement is completed, the remaining caisson units of the caisson module are hoisted in sequence, and the gravity settlement of the caisson units is guided by the pre-fixed foundation piles. Initiate assisted sinking construction until the caisson module at the predetermined settlement coordinate reaches the design depth; The foundation pile connection was disconnected and the piles were driven to complete the installation of the first caisson module and the settlement of the first caisson module was completed. S3. Using the first caisson module as a reference, advance the construction to both sides, and construct the remaining caisson modules in sequence according to the construction method of step S2 until the marine foundation structure is completed. S4. Install rigid connecting rings to achieve rigid splicing of caisson modules; S5. Anchoring systems are evenly distributed on the inner side of the marine foundation structure; S6. Assemble the wave-blocking assembly structure; S7. Construction inside each caisson unit.

[0013] In one possible embodiment, after the internal construction of the caisson unit is completed, micro-expansion concrete is poured into the gap between the foundation pile and the pile hole.

[0014] In one possible embodiment, the internal construction of the caisson unit in step S7 includes: laying an impermeable cloth at the bottom of the caisson unit, filling self-compacting soil bags to form a closed condition, pumping out water to form a dry construction condition, and then sequentially implementing the laying of crushed stone layer, laying of subbase layer, pouring of reinforced concrete for the bottom slab, and internal backfilling from bottom to top.

[0015] Compared with the prior art, the modular assembly of pile foundation caissons for artificial island marine structures and its construction method of the present invention have the following beneficial effects: 1. The marine structure of this artificial island uses hexagonal cross-section caisson units as modular units, combined with flexible sealing water-stopping structures, guiding structures for pile holes and foundation piles, rigid connection structures, and anchoring systems. On the one hand, it can realize multi-form modular enclosure assembly of caisson units, with a short construction period and good sealing between caisson units, which can improve the structural adaptability under different artificial island configurations. On the other hand, it can maintain the joint sealing when there are splicing errors in the caisson units and during the settlement process, improving the water-stopping effect and settlement stability of the enclosure structure. Furthermore, through the cooperation of rigid connecting rings and flexible water-stopping structures, it can maintain the overall structural rigidity while allowing slight deformation of the joints. 2. This construction method is suitable for the above-mentioned marine structures. By controlling and guiding the settlement of the caisson units through the pre-fixed foundation piles of the bottom caisson units, the caisson units settle in a controlled manner and are accurately stacked. After the elevation settlement of the caisson modules, the pile planting construction facilitates the correction of the caisson modules and the construction of a stable boundary structure with a certain resistance to wind and wave impact, thereby improving the feasibility of the overall construction and facilitating subsequent land reclamation, foundation treatment and external protection construction. Attached Figure Description

[0016] Figure 1 This is a structural diagram of the caisson unit disclosed in this invention; Figure 2 This is a diagram showing the splicing structure of the caisson unit disclosed in this invention; Figure 3 This is a cross-sectional structural diagram of the caisson module disclosed in this invention; Figure 4 This is an assembly structure diagram of the circular marine structure disclosed in this invention; Figure 5 This is an assembly structure diagram of the square marine engineering structure disclosed in this invention; Figure 6 This is a linear assembly structure diagram of the caisson unit disclosed in this invention; Figure 7 This is a diagram of the arc-shaped assembly structure of the caisson unit disclosed in this invention; Figure 8 This is a structural diagram of the wave-blocking unit disclosed in this invention.

[0017] Attached image labels: 100. External connecting beam; 200. Internal connecting beam; 300. Caisson module; 310. Caisson unit; 311. Pile hole; 312. Insertion structure; 313. Embedded structure; 320. Foundation pile; 330. Crushed stone layer; 340. Subbase layer; 350. Concrete base slab; 400. Anchoring system; 500. Rubber waterstop strip; 510. Embedded structure; 520. Deformation ring; 600. Wave-breaking unit. Detailed Implementation

[0018] 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 merely the best 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.

[0019] The term "embodiment" as used herein means that a particular method, step, or content described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0020] This application provides an embodiment of an artificial island marine structure with modular assembly of pile foundation caissons, such as... Figures 1-8 As shown, the structure includes foundation piles 320, rigid connecting rings, and caisson units 310. Multiple caisson units 310 are continuously spliced ​​to form an enclosed structure. The caisson unit 310 is a cylindrical structure with a regular hexagonal cross-section. Compared to traditional cylindrical and square caisson units 310, the caisson unit 310 in this embodiment can achieve modular splicing of various structures, such as... Figures 6-7 As shown, by using two parallel opposing surfaces to assemble along a linear assembly line or an arc-shaped assembly line, the linear assembly can form a closed structure like... Figure 5 The square artificial island marine structure shown is formed by arc-shaped splicing and enclosing, as... Figure 4 The circular artificial island marine structure shown; in addition, the caisson unit 310 of this embodiment has a large area of ​​docking and splicing surface, which makes it easy to achieve gap sealing. At the same time, after the caisson unit 310 of this structure is assembled, it can form a sawtooth surface on the outer side of the marine structure, which not only has a certain wave dissipation capability, but also can limit the structure of the caisson unit 310 on the horizontal plane in cooperation with the rigid connection structure, thereby improving the water-stopping sealing effect between the caisson units 310. Adjacent caisson units 310 are pre-installed with joints to prevent mutual compression. These joints are flexibly sealed using a flexible water-stop structure, specifically rubber water-stop strips 500. These rubber water-stop strips 500 are staggered and pre-embedded on the two parallel mating surfaces of the caisson unit 310. Figure 1 and Figure 2 As shown, the rubber waterstop strip 500 includes a pre-embedded structure 510 and a deformable ring 520. The deformable ring 520 is located at the end of the pre-embedded structure 510 and extends from the mating surface. Its outer diameter is D, which can seal joints with a width of 0.38D to 0.6D. For design joints with a smaller width, a deformation groove can be opened on the mating surface. The deformation groove can guide the deformation of the root of the deformable ring 520 and increase the contact area between the end of the deformable ring 520 and the other mating surface. The flexible waterstop structure can not only compress and seal the water, but also deform to adapt to the variable joints between adjacent caisson units 310, so as to meet the sealing requirements when the adjacent caisson units 310 settle relative to each other during the self-weight settlement process. In addition, to ensure the vertical settlement of the caisson unit 310, multiple pile holes 311 are evenly arranged on the caisson unit 310, through which foundation piles 320 can be selectively installed to position and guide the settlement of the caisson unit 310. The foundation piles 320 and the pile holes 311 are fitted with a gap to accommodate positioning errors, resistance-free settlement, and fine-tuning of the squeeze-stopping mechanism. The limiting effect of the foundation piles 320 can also effectively prevent uneven stress during settlement from causing local water-stopping failure. The foundation piles 320 are temporarily connected by a pre-strengthened structure (not shown in the figure). In some possible embodiments, the pre-strengthened structure can be a threaded assembly (shown in the figure). (Not shown) A detachable connection is made, with a threaded ring sleeved at the end of the foundation pile 320 and a threaded sleeve pre-embedded in the bottom caisson unit 310; in some possible embodiments, the pre-fixed structure can also be connected by casting, with a concrete connection structure of a certain thickness poured and filled between the pile hole 311 and the foundation pile 320; after the settlement and calibration of the caisson module 300 are completed, the threaded connection is disassembled by rotating the foundation pile 320 or the concrete connection structure is destroyed by knocking, so that the foundation pile 320 is disconnected from the pile hole 311, and the foundation pile 320 is driven to complete the pile planting. At this time, the foundation pile 320 serves as the foundation pile of the marine engineering foundation structure; After all the caisson modules 300 have completed their depth settlement and closure, all the caisson modules 300 of the marine foundation structure are connected and enclosed by a rigid connection structure. The rigid connection structure is a steel component, which includes an outer connecting beam 100 and an inner connecting beam 200. The rigid connection structure can limit and assemble the caisson units 310 of N different caisson modules 300, adjust and connect adjacent rigid connection structures to form a rigid connection ring. Multiple rigid connection rings are evenly arranged on the marine foundation structure. It should be ensured that at least one rigid connection ring is set on each layer of caisson unit 310 exposed outside the seabed foundation. The marine foundation structure is constructed as a force-bearing community under the inner and outer hoop connections of the rigid connection rings.

[0021] As a further technical solution, in order to achieve mutual restraint between the caisson units 310, both the outer connecting beam 100 and the inner connecting beam 200 include connecting beams and restraining parts. The connecting beams are linear beams or arc beams adapted to the marine structure of the artificial island. The restraining parts are formed by the protrusions on the inner side of the connecting beams to form a sawtooth structure. The sawtooth structure is adapted to the corners on both sides of the caisson unit 310 and is used to restrain the width of the seaside joint and the landside joint between the caisson units 310, so as to ensure the water-stopping effect of the flexible water-stopping structure.

[0022] In some possible embodiments, such as Figure 3 As shown, the upper end of the caisson unit 310 is provided with a plug-in structure 312, which has a guide slope. The lower end of the caisson unit 310 is provided with an embedding structure 313 that is compatible with the plug-in structure 312. Under the guidance of the foundation pile 320 and gravity settlement, the adjacent caisson units 310 automatically achieve accurate alignment and precise overlap through the plug-in structure 312 and the embedding structure 313.

[0023] Traditional marine structures prevent erosion by installing facing blocks or raising wave walls on the outer side of the breakwater. In this embodiment, the marine structure includes a lower marine foundation structure and an upper wave-blocking assembly structure. The wave-blocking assembly structure is formed by assembling wave-blocking units 600 with the marine foundation structure directly below. To install the barrier structure along the outer edge of the caisson unit 310, the wave-blocking unit 600 in this embodiment adopts the following... Figure 8 As shown, the wave-blocking unit 600 has a triangular structure, and its wave-blocking surface structure is basically the same as the seaside structure of the caisson unit 310. In addition, in order to construct a closable barrier structure above the marine foundation structure, the wave-blocking unit 600 is also provided with a docking surface and a flexible water-stop structure pre-embedded in the docking surface. After the adjacent wave-blocking units 600 are fixed, they form a sealed water-stop by squeezing the flexible water-stop structure, which facilitates the reclamation construction. The wave-blocking unit 600 can be connected, limited and guided by the foundation piles 320 of the marine foundation structure to stabilize and position the wave-blocking unit 600. The positioning hole of the wave-blocking unit 600 is aligned with the pile hole 311 directly below it and is inserted and positioned with the foundation pile 320 exposed on the upper surface of the marine foundation structure.

[0024] As a further technical solution, the marine engineering foundation structure is equipped with an anchoring system 400. Each caisson unit 310 exposed on the seabed foundation is equipped with at least one anchoring system 400. One end of the anchoring system 400 is connected to the lower caisson unit 310, and the other end is anchored to the landside foundation of the artificial island marine engineering structure. The anchoring system 400 can provide horizontal tension towards the landside and vertical tension downward for the anchoring rope. The bottom of the caisson module 300 extends into the seabed foundation to form a cantilever beam structure. The active pre-tension is implemented by the anchoring system 400, which improves the structural strength of the caisson module 300 during the reclamation process and the structural stability under wave and tidal impact. The active pre-tension and the structural limit of the rigid connection structure work together to ensure that the joints of the marine engineering structure are kept in a favorable compression state when subjected to reciprocating wave loads.

[0025] This application also provides a method for constructing an artificial island marine structure, including the following steps and contents: S1. First, prefabricate the caisson units 310 in batches and embed flexible water-stop structures according to the design joint width. The joint width between the joint surfaces is located at or less than the preset sealing range of the flexible water-stop structure. In the event of certain installation errors during on-site hoisting, the joint width deviation can be compensated by the compression deformation of the flexible water-stop structure to ensure that the joint still has reliable water-stopping capability. Assemble the bottom caisson unit 310 and foundation piles 320. There are at least 4 foundation piles 320, which are symmetrically distributed in pairs. The foundation piles 320 are temporarily pre-fixed in the pile holes 311. The main body of the foundation pile 320 is coaxial with the pile hole 311 and a gap is provided. In some possible specific embodiments, a gap of 30mm to 50mm is reserved between the main body of the foundation pile 320 and the pile hole 311. This gap is used to compensate for the installation error between the foundation pile 320 and the caisson unit 310, and to reserve space for subsequent pouring. The foundation piles 320 are used to control and adjust the gravity settlement of the bottom caisson unit 310 to ensure that it settles accurately at the predetermined settlement coordinate. In addition, the bottom caisson unit 310 is used as a basic positioning frame to guide the settlement of the subsequent caisson unit 310 by the estimated foundation piles 320, so that they are accurately aligned and overlapped. S2, Layered construction method for the first caisson module 300: First, the caisson module 300 includes foundation piles 320 and multi-layer caisson units 310 connected in series; the bottom caisson unit 310 is hoisted to the predetermined settlement coordinate, and the horizontal deviation and verticality of the bottom caisson unit 310 during the descent process are controlled by the pre-fixed foundation piles 320, so that the caisson unit 310 initially settles on the mud surface of the predetermined settlement coordinate. The stability of the bottom caisson unit 310 is checked and adjusted by the foundation piles 320. In some possible embodiments, the tilt rate of the foundation piles 320 is controlled to be ≤1 / 200, and the initial settlement, initial elevation depth and tilt data are recorded. Next, the remaining caisson units 310 are hoisted and assembled onto the foundation piles 320 in sequence, with a permissible planar deviation of ≤50mm. The sinking path, horizontal offset, and verticality of the caisson units 310 are constrained by the pre-fixed foundation piles 320, so that the upper-layer sinking unit can accurately sink to the top of the lower-layer sinking unit under the action of gravity. The bottom perimeter plug-in structure 312 automatically slides into the embedding structure 313 by gravity, realizing the initial alignment and embedding of the upper and lower layers. When the gravity sinking approaches the lower-layer caisson unit 310, the sinking speed of the sinking unit is controlled to ≤80mm / h to prevent impact damage to the plug-in structure 312 or the embedding structure 313. When the caisson unit 310 cannot sink under its own weight, or when the settlement rate is ≤10mm / h, the auxiliary sinking process is initiated. Depending on the condition of the seabed foundation, dredging (suitable for fine sand and silty soil layers, etc.) or excavation (suitable for hard clay and gravel layers, etc.) is used to assist settlement. Verticality measuring instruments, elevation scales, and displacement monitoring points are arranged at control points in all directions of the caisson unit 310 exposed above the water surface or on each pile 320 to calculate the seabed foundation elevation and tilt direction. For the side with a higher mud surface, excavation or dredging is prioritized; for the side with a lower mud surface, lowering is carried out. Low excavation or suction intensity should be used to prevent further tilting of the caisson module 300. The auxiliary sinking process should adopt a zoned, symmetrical, and intermittent construction method. In some specific embodiments, the auxiliary sinking rate should be controlled at 300 mm / h, and the time for a single auxiliary construction should be ≤2h. During this period, stability, center coordinates, verticality, attitude, and joint status testing should be suspended, and the next round of auxiliary sinking construction should be adjusted in a timely manner. When the caisson module 300 sinks to the design depth of 1m, the construction intensity should be reduced and the monitoring frequency should be increased until the caisson module 300 at the predetermined settlement coordinate has settled to the design depth evenly. After the caisson module 300 has settled and stabilized at the design depth, the foundation piles 320 are disassembled from the pile holes 311 or the temporary connections are broken by force to allow the foundation piles 320 to enter the pile planting process. For minor tilts or positional deviations that cannot be corrected during the auxiliary sinking process, slight corrections can be made during the pile planting process by adjusting the planting angle or planting sequence based on the center coordinates and verticality of the top caisson unit 310 after it is actually in place. The piles can be planted in sections using a vibratory hammer or a punch hammer, with the verticality and top elevation of the foundation piles 320 monitored simultaneously. At this point, the settlement of the first caisson module 300 was completed; S3. Using the first caisson module 300 as a reference, simultaneously advance the construction of adjacent caisson modules 300 on both sides along the designed assembly line. Construct the remaining caisson modules 300 in sequence according to the construction method in step S2. Based on the actual positioning center coordinates of the completed caisson module 300 and the overall verticality deviation, dynamically correct the settlement coordinates of the caisson module 300 under construction according to the joint width design requirements, so that the actual joint width is within the effective sealing range of the flexible water-stop structure and the overall assembly line meets the design requirements. The adjacent bottom-level caisson units 310 on both sides are preferably lowered simultaneously. Utilizing the squeezing action during the simultaneous lowering of the adjacent bottom-level caisson units 310, the mating surfaces of the adjacent caisson units 310 gradually approach and squeeze the flexible water-stop structure, causing the flexible water-stop structure to compress and deform, thus sealing the joints. Simultaneously, the adjacent caisson modules 300 on both sides form a relatively balanced lateral constraint on the first caisson module 300, which can push the caisson units 310 of each layer of the first caisson module 300 to make minor adjustments to their centering, reducing the risk of lateral compression and displacement caused by unilateral lowering. In the subsequent construction of the caisson module 300, the docking surface of the completed caisson module 300 can be used as a planar guide surface to assist in guiding the gravity sinking of the caisson unit 310 to be installed; preferably, the caisson modules 300 on both sides of the assembly line adopt a symmetrical advancement method to avoid the secondary displacement, cracking or water-stopping failure of the completed caisson module 300 caused by long-term single-sided construction. Construction will continue in this manner until the marine engineering foundation structure is completed and the closure is finished; S4. Install rigid connecting rings to achieve rigid splicing of caisson modules 300; Based on the settlement rate, horizontal displacement, joint width change and tilt change of the multi-point monitoring caisson module 300, after the marine foundation structure enters a stable state, several rigid connecting rings are evenly installed in the height direction of the marine foundation structure. Among them, each caisson unit 310 exposed outside the seabed foundation should be equipped with at least one rigid connecting ring to improve the overall anti-lateral displacement and anti-fracture capacity of the marine foundation structure. A rigid connection structure is installed in groups of N caisson units 310. The outer connecting beam 100 and the inner connecting beam 200 clamp the caisson unit group 310 from both sides (i.e., the sea side and the land side) to achieve splicing. The serrated limiting parts of the two beams cooperate with the protruding edges of the caisson unit 310. After the rigid connection structure is connected in series, it forms a rigid connecting ring, which provides all-round relative limiting for each caisson unit 310. Thus, while retaining the micro-deformation adaptability of the joint of the flexible water-stop structure, it improves the overall wave resistance, lateral earth pressure resistance, and uneven settlement disturbance resistance of the marine foundation structure. The outer connecting beam 100 and the inner connecting beam 200 can be connected by connectors set at the ends of the connecting beams or at the pre-embedded connection nodes. S5. Anchoring systems 400 are uniformly arranged on the inner side of the marine foundation structure. The anchoring system 400 includes anchor ropes and anchor rods. The anchor rods are anchored in the landside area enclosed by the marine foundation structure. The anchor ropes are connected to the caisson units 310 through embedded parts or rigid connection structures. After tensioning, an active pre-tension force is applied towards the landside. The active pre-tension force is used to counteract the lateral action of the reclamation construction on the marine foundation structure and to control the joint width and overall alignment between the caisson modules 300. Multiple anchoring systems 400 are distributed along the height direction and assembly line direction of the marine foundation structure. Preferably, the anchoring points of each anchoring system 400 on the marine foundation structure are distributed in a staggered pattern to avoid local stress concentration. S6. Assemble the wave-blocking assembly structure; splice the wave-blocking unit 600 along the edge of the marine foundation structure, aligning the sea side of the wave-blocking unit 600 with the outer side of the caisson unit 310 directly below it, so that the wave-blocking assembly structure and the marine foundation structure together form a continuous outer sea protection surface; when installing the wave-blocking unit 600, use two or three foundation piles 320 on the sea side of the caisson unit 310 directly below for positioning; the wave-blocking units 600 are sealed by compression through a flexible water-stopping structure, forming a continuous airtight enclosure on the top of the marine foundation structure, providing boundary sealing conditions for pumping water inside the caisson unit 310, dry construction, and subsequent land reclamation; S7. Construction inside each caisson unit 310: A waterproof cloth is laid at the bottom of the bottom caisson unit 310. Then, self-compacting soil bags are thrown in. After being stacked at the bottom, the self-compacting soil bags can adhere to the uneven foundation surface by their own weight and form a bottom sealing layer together with the waterproof cloth. Next, water is pumped out to create dry construction conditions. Finally, from bottom to top, the crushed stone layer 330 is laid, the cushion layer 340 is laid, the steel reinforcement structure is tied, and the concrete base slab 350 is poured. After the concrete base slab 350 is poured and reaches the design strength, the inside of the caisson unit 310 is backfilled. The backfill material can be sand, crushed stone, solidified soil, lightweight backfill material, or other fill material that meets the design requirements. After the internal construction is completed, micro-expansion concrete is poured into the gap between the foundation pile 320 and the pile hole 311. The micro-expansion concrete fills the annular gap between the outer wall of the foundation pile 320 and the wall of the pile hole 311, and after hardening, the foundation pile 320 and the caisson unit 310 are connected as a whole.

[0026] The directional terms "outer," "inner," "upper," "lower," "side," "end," "high," "seaside," and "landside" mentioned in this article are based on... Figures 1-8 The orientation or positional relationship shown in the corresponding figures, or the orientation relationship under construction conditions; these terms are mainly for the purpose of better describing the invention and its embodiments, and are not intended to limit the indicated device, element or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0027] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A modularly assembled artificial island marine structure based on pile foundation caissons, characterized in that, The structure includes caisson units, foundation piles, and rigid connecting rings. Each caisson unit has a hexagonal cross-section, and several caisson units are continuously assembled along the same assembly line to form an enclosed structure. Joints are pre-set between adjacent caisson units, and flexible water-stop structures are provided on their mating surfaces to form a pressure-sealing water stop when adjacent caisson units are assembled, thus sealing the joints. Multiple pile holes are evenly arranged on each caisson unit, and these pile holes are spaced with the foundation piles to position and guide the settlement of the caisson unit. The rigid connecting rings are fitted around the inner and outer sides of the enclosed structure to assemble all the caisson units into a single, load-bearing marine foundation structure.

2. The artificial island marine structure according to claim 1, characterized in that: The rigid connecting ring is formed by connecting several rigid connecting structures in sequence to form a loop structure. The rigid connecting structure includes an outer connecting beam and an inner connecting beam. The outer connecting beam and the inner connecting beam respectively limit the edges and corners of the outer and inner sides of the caisson unit. Both include a connecting beam and a limiting part. The limiting part extends inward from the inner side of the connecting beam to form a sawtooth structure. The sawtooth structure is adapted to the edges and corners of the caisson unit.

3. The artificial island marine structure according to claim 2, characterized in that: The flexible water-stop structure is a rubber water-stop strip, which is pre-embedded on the mating surface of the caisson unit. Its sealing end extends out from the mating surface of the caisson unit and is squeezed to adapt to the joint.

4. The artificial island marine structure according to claim 3, characterized in that: The sealing end of the rubber waterstop strip is a deformable ring with an outer diameter of D and a preset sealing range of 0.38D to 0.6D.

5. The artificial island marine structure according to claim 1, characterized in that: It also includes a wave-blocking assembly structure, which is set on the top of the marine foundation structure. It is formed by continuously splicing and enclosing several wave-blocking units. The wave-blocking units are arranged along the outer edge of the upper end of the caisson unit and have positioning holes. The positioning holes cooperate with the foundation piles directly below them to use the foundation piles of the marine foundation structure for positioning.

6. The artificial island marine structure according to claim 1, characterized in that: The marine foundation structure is equipped with an anchoring system, one end of which is connected to the caisson unit, and the other end is anchored to the landside foundation of the marine foundation structure to apply active pre-tension.

7. The artificial island marine structure according to claim 1, characterized in that: The upper end of the caisson unit is provided with a plug-in structure, and the lower end is provided with an embedding structure adapted to the plug-in structure for plug-in connection of the caisson units of adjacent layers.

8. A construction method for an artificial island marine structure, comprising constructing an artificial island marine structure using modular assembly of pile foundation caissons as described in any one of claims 1 to 7, characterized in that, Includes the following steps and content: S1. Prefabricate the caisson units in batches, assemble the bottom caisson units with the foundation piles, and pre-fix the foundation piles in their pile holes; S2. Layered construction of the first caisson module; the caisson module includes the foundation pile and the multiple layers of the caisson units connected in series; after the bottom layer of the caisson unit is hoisted to the predetermined settlement coordinate and the initial settlement is completed, the remaining layers of the caisson units of the caisson module are hoisted in sequence, and the gravity settlement of the caisson units is guided by the pre-fixed foundation pile; In conjunction with the auxiliary sinking construction, until the caisson module at the predetermined settlement coordinate reaches the design depth; The foundation pile connection is disconnected and the pile is driven to complete the settlement of the first caisson module; S3. Using the first caisson module as a reference, advance the construction to both sides, and construct the remaining caisson modules in sequence according to the construction method in step S2, until the marine foundation structure is completed. S4. Install the rigid connecting ring to achieve rigid splicing of the caisson module; S5. An anchoring system is evenly distributed on the inner side of the marine foundation structure. S6. Assemble the wave-blocking assembly structure; S7. Construct the interior of each of the aforementioned caisson units.

9. The construction method for artificial island marine structures according to claim 8, characterized in that: Step S7 also includes pouring micro-expansion concrete into the gap between the foundation pile and the pile hole after the internal construction of the caisson unit is completed.

10. The construction method for artificial island marine structures according to claim 8, characterized in that: The internal construction of the caisson unit in step S7 includes: laying an impermeable cloth at the bottom of the caisson unit, filling self-compacting soil bags to form a closed condition, pumping out water to form a dry construction condition, and then carrying out the following steps from bottom to top: laying a crushed stone layer, laying a subbase layer, pouring a reinforced concrete base slab, and backfilling the interior.

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