Simultaneous positioning construction method for multiple piles in offshore photovoltaic systems

Abstract

This disclosure provides a method for synchronous positioning of multiple piles in offshore photovoltaic (PV) construction, relating to the field of offshore PV technology. The method includes: Step S1, the piling vessel travels to a preset area and undergoes three-level dynamic positioning, the piling vessel carrying a first number of piles; wherein, the three-level dynamic positioning includes GPS coarse positioning, four-anchor symmetrical anchoring coarse adjustment, and mobile trolley positioning pile fine adjustment; Step S2, using the piling vessel's dual-crane system, multiple piles are synchronously fed into the pile gripper of the cantilever fixture; Step S3, multiple piling hammers are simultaneously activated for suspended piling, employing a composite piling process combining self-sinking and hammer penetration, with the pile top elevation controlled by an elevation control system; Step S4, after piling is completed, the positioning piles are extracted, and the piling vessel is anchored and moved to the next work area. This method can achieve synchronous positioning of multiple piles, improving the positioning efficiency of the piles.

Description

Technical Field

[0001] This disclosure relates to the field of offshore photovoltaic technology, and more specifically, to a method for synchronous positioning and construction of multiple offshore photovoltaic piles. Background Technology

[0002] As an innovative form of energy development, offshore solar power is playing an increasingly crucial role in the global energy transition process due to its unique advantages such as cleanliness and renewability. However, among the many stages of offshore solar power construction, pile foundation construction is an extremely important foundational component. Offshore solar power construction utilizes a large number of pile foundation structures. Fixed pile foundation structures are fixed at one end in the sea and extend above sea level at the other end, thus serving as the foundation for subsequent fixed construction. The positioning and construction of the pile foundation not only determines the support performance of the pile foundation but also affects the overall construction efficiency of offshore solar power.

[0003] Traditional pile driving methods have limitations in terms of positioning accuracy and construction efficiency. Currently, the commonly used pile positioning method often involves positioning each pile individually, which is insufficient to meet the demands of large-scale offshore photovoltaic pile groups and high pile driving accuracy.

[0004] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] In view of this, a method for synchronous positioning of multiple offshore photovoltaic piles is provided. This method can realize synchronous positioning of multiple offshore photovoltaic piles, improve the positioning efficiency of the piles, and also improve the positioning accuracy and driving accuracy of the piles, thereby improving the positioning reliability of the piles.

[0006] Other features and advantages of this disclosure will become apparent from the following detailed description, or may be learned in part from practice of this disclosure.

[0007] According to one aspect of this disclosure, a method for synchronous positioning and construction of multiple piles for offshore photovoltaic systems is provided. The pile-driving vessel includes a dual-crane system, multiple cantilever fixtures mounted on both sides of the hull, and a mobile trolley. The method includes: Step S1: The piling vessel travels to the preset area and performs three-level dynamic positioning on the piling vessel, which carries a first number of piles; wherein, the three-level dynamic positioning includes GPS coarse positioning, four-anchor symmetrical anchoring coarse adjustment and positioning pile fine adjustment by the mobile trolley. Step S2: Using the dual crane system of the piling vessel, multiple pile foundations are simultaneously fed into the pile gripper of the cantilever tool; Step S3: Simultaneously start multiple pile hammers for suspended pile driving, adopting a composite pile driving process that combines self-sinking of piles with hammer penetration, and adjust the pile top elevation through an elevation control system. Step S4: After completing the piling, pull out the positioning pile, and the piling vessel is anchored and moved to the next work area.

[0008] In one exemplary embodiment of this disclosure, prior to step S1, the method further includes: Provide a transport vessel, the transport vessel comprising a second number of pile foundations, the first number being less than the second number; The transport vessel travels to the side of the piling vessel, and the transport vessel and the piling vessel are positioned in a T-shape. The pile foundation is transferred from the transport ship to the piling ship using a two-point lifting method.

[0009] In one exemplary embodiment of this disclosure, the pile foundations are loaded onto the transport ship in a layered and cross-stacking manner, with support members installed between the layers, and different types of pile foundations are loaded in different areas.

[0010] In an exemplary embodiment of this disclosure, in step S1, the coarse adjustment of the four anchors symmetrically anchoring includes: the anchoring angle of the four anchors is ±30° to 45° of the bow and stern line of the piling vessel, and the anchor rope length is ≥ 4 times the water depth; Fine-tuning of the mobile trolley includes: X / Y / Z three-way adjustment via the hydraulic cylinders of the mobile trolley, with an adjustment accuracy of ±1cm.

[0011] In one exemplary embodiment of this disclosure, the method further includes: The positioning deviation of the piling vessel is obtained, and it is determined whether the positioning deviation is within a preset range, wherein the sampling frequency for obtaining the positioning deviation is ≥10Hz; If the positioning deviation exceeds the preset range, the positioning position of the piling vessel is adjusted until the positioning deviation is within the preset range.

[0012] In one exemplary embodiment of this disclosure, in step S2, the clamping force of the pile gripper is ≥1.2 times the pile weight, and the clamping pressure is evenly distributed; Step S2 also includes: enabling wave compensation for the piling vessel, with a compensation range of ≥±1m.

[0013] In one exemplary embodiment of this disclosure, in step 3, during the pile driving self-sinking stage, the pile driving force is controlled to be 0.2-0.5 times the ultimate bearing capacity of the pile body; The sinking speed of the pile body satisfies v= Where K = 0.6-0.8, D is the pile diameter, and g is the acceleration due to gravity; During the hammering penetration stage, the hammering energy is dynamically adjusted by the penetration degree, and the penetration degree is positively correlated with the hammering energy. During the final hammer control phase, the average penetration of the last 10 blows is controlled to be ≤2mm / blow.

[0014] In an exemplary embodiment of this disclosure, after step S3, the elevation deviation between the plurality of pile foundations is ≤25mm, the levelness deviation of the end face of each pile foundation is ≤0.5%, the deviation of the center distance between the pile tops of the plurality of pile foundations is ≤100mm, and the inclination deviation of the longitudinal axis of the pile foundation is <5‰.

[0015] In one exemplary embodiment of this disclosure, step S4 includes: The positioning pile was pulled out using a hydraulic buffer-type pile extraction method; A navigation system is used to plan the ship's movement path; the ship's movement speed is ≤0.3 knots, and the positioning repeatability is ±5cm.

[0016] In one exemplary embodiment of this disclosure, the pile foundation includes at least one of steel piles or PHC piles; During the hammer penetration stage, the steel pile adopts the first hammer driving mode, the parameters of which include: single hammer energy ≥ 200kJ, number of blows ≤ 80 blows / m; the PHC pile adopts the second hammer driving mode, the parameters of which include: single hammer energy ≤ 150kJ, number of blows ≥ 120 blows / m.

[0017] The offshore photovoltaic multi-pile synchronous positioning construction method disclosed herein improves the pile driving accuracy through three-level dynamic positioning of the piling vessel. Furthermore, by simultaneously feeding multiple piles into the pile grippers of multiple cantilever fixtures installed on the piling vessel, and then simultaneously activating multiple pile hammers for suspended piling, synchronous positioning of multiple piles can be achieved, improving construction efficiency and shortening construction time. During the synchronous suspended piling process, controlling the top elevation of multiple piles improves the driving accuracy, reduces positioning errors between piles, and enhances the positioning reliability, providing a reliable structural foundation for subsequent photovoltaic module support. In addition, this construction process integrates pile transportation, positioning, and piling, achieving integrated pile positioning operation.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0020] Figure 1 This is a flowchart of a method for synchronous positioning and construction of multiple marine photovoltaic piles, as shown in an exemplary embodiment of this disclosure.

[0021] Figure 2 This is a flowchart of a synchronous positioning construction method for four offshore photovoltaic piles, as shown in an exemplary embodiment of this disclosure. Detailed Implementation

[0022] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0023] Although relative terms such as "up" and "down" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples shown in the accompanying drawings. It is understood that if the device of the icon is flipped upside down, the component described as "up" will become the component described as "down." When a structure is "up" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0024] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0025] In related technologies, pile foundations serve as the supporting structure for offshore photovoltaic (PV) modules, and their reliability in positioning at sea affects the overall lifespan of the PV system. Due to the unique environmental factors affecting offshore PV, large-scale pile groups are required to support the PV system. Traditional pile foundation positioning typically employs a method of driving individual piles one by one, which is time-consuming, inefficient, and unsuitable for the construction requirements of large-scale pile groups and high-precision positioning.

[0026] Based on this, the present disclosure provides a method for synchronous positioning and construction of multiple offshore photovoltaic piles, such as... Figure 1 As shown, the method includes steps S1 to S4.

[0027] In step S1: The piling vessel travels to the preset area and is subjected to three-level dynamic positioning. The piling vessel carries the first number of piles. The three-level dynamic positioning includes GPS coarse positioning, four-anchor symmetrical anchoring coarse adjustment, and positioning pile fine adjustment by the mobile trolley. Step S2: Use the double crane system of the piling vessel to simultaneously feed multiple piles into the pile gripper of the cantilever tool; Step S3: Simultaneously start multiple pile hammers for suspended pile driving, adopting a composite pile driving process that combines self-sinking pile driving with hammer penetration, and adjust the pile top elevation through an elevation control system. Step S4: After completing the piling, pull out the positioning pile, and move the piling vessel to the next work area by anchoring.

[0028] The offshore photovoltaic multi-pile synchronous positioning construction method disclosed herein improves the pile driving accuracy through three-level dynamic positioning of the piling vessel. Furthermore, by simultaneously feeding multiple piles into the pile grippers of multiple cantilever fixtures installed on the piling vessel, and then simultaneously activating multiple pile hammers for suspended piling, synchronous positioning of multiple piles can be achieved, improving construction efficiency and shortening construction time. During the synchronous suspended piling process, controlling the top elevation of multiple piles improves the driving accuracy, reduces positioning errors between piles, and enhances the positioning reliability, providing a reliable structural foundation for subsequent photovoltaic module support. In addition, this construction process integrates pile transportation, positioning, and piling, achieving integrated pile positioning operation.

[0029] The following will describe in detail each step of the offshore photovoltaic multi-pile synchronous positioning construction method provided in the embodiments of this disclosure with reference to the accompanying drawings: In the embodiments provided in this disclosure, in step S1, the piling vessel travels to a preset area, and the piling vessel is dynamically positioned at three levels, carrying a first number of piles.

[0030] The three-level dynamic positioning system includes GPS coarse positioning, four-anchor symmetrical anchoring coarse adjustment, and positioning pile fine adjustment of the mobile trolley.

[0031] The piling vessel includes a dual-crane system, which may include cranes located at the bow and stern of the piling vessel. Each crane can perform functions such as lifting and transferring pile foundations. The specific structure of the cranes can be obtained in the art, and any cranes that can be used for pile foundation lifting construction can be used in the piling vessel provided in this disclosure.

[0032] The piling vessel includes multiple cantilever fixtures mounted on both sides of the hull. Each cantilever fixture may include a hydraulic telescopic boom, a clamping device, and a pin mechanism. The hydraulic telescopic boom can swing horizontally with an amplitude of ±45°. The adaptive clamping device can be an adaptive clamp whose diameter can be adjusted according to the diameter of the pile being clamped. To prevent damage to the pile during clamping, the clamping device's lining can be a high-friction coefficient rubber layer. The pin mechanism is a quick-locking pin that secures the pile when it is placed inside the clamp. The tensile strength of the pin mechanism can be greater than or equal to 500kN to ensure sufficient strength. It should be noted that to ensure the structural symmetry of the piling vessel, multiple cantilever fixtures are typically arranged symmetrically to guarantee the vessel's stability.

[0033] The piling vessel includes a mobile trolley, which can be a positioning pile trolley. This trolley is hydraulically driven to move, lift, change piles, and position the vessel, adjusting its working posture and construction accuracy. Of course, the mobile trolley can also be a slipway trolley, an active trolley, or a combination of other types of trolleys to meet the specific needs of the piling vessel.

[0034] The piling vessel disclosed herein integrates a dual-crane system, multiple cantilever fixtures, and a mobile trolley, among other structures. It can integrate multiple functions such as hoisting, positioning, and fixing. The piling vessel can also load a first number of pile foundations on its deck. The pile foundations can be transported to a preset area via the piling vessel. After the piling vessel is positioned, construction processes such as pile driving can be carried out directly. This piling vessel achieves multi-functional integration and can improve piling efficiency.

[0035] The piling vessel travels to the pre-set area, which can refer to the sea area where a large number of piles need to be positioned. After the piles are positioned, photovoltaic modules can be positioned within the pre-set area to meet the power generation needs. The pre-set area can be determined according to the actual design requirements of offshore photovoltaic systems.

[0036] After the piling vessel reaches the preset area, it undergoes three levels of dynamic positioning: GPS coarse positioning, four-anchor symmetrical anchoring coarse adjustment, and positioning pile fine adjustment by the moving trolley.

[0037] In some embodiments, the piling vessel is first coarsely positioned using GPS within a preset area. The GPS can be installed on the piling vessel to enable autonomous coarse positioning of the piling vessel. This coarse positioning can, based on the coordinates of the pre-planned pre-piling area, at least ensure that the piling vessel travels to the vicinity of the pre-piling area or directly into the pre-piling area.

[0038] In some embodiments, after GPS coarse positioning, the anchor boat assists the piling vessel in anchoring. By raising and lowering the four anchors, which can be four symmetrical anchors, the position of the piling vessel is coarsely adjusted. The anchoring distance is determined based on the soil quality, water depth, current, wind direction, and anchor weight of the anchoring area.

[0039] After coarsely positioning the piling vessel, the method also includes extending the cantilever fixtures on both sides, and then fine-tuning and micro-adjusting to ensure that the center of the multiple cantilever fixtures is located on the pre-pile position.

[0040] In some embodiments, the four-anchor symmetrical anchoring coarse adjustment includes setting the four anchors at angles ±30° to 45° from the bow and stern lines of the piling vessel, with anchor rope lengths ≥ 4 times the water depth. For example, if the water depth is 3 to 15 meters, the anchor rope length can be 12 to 60 meters to ensure the coarse adjustment effect of the piling vessel. The four-anchor symmetrical anchoring coarse adjustment can achieve positioning of the piling vessel along its length, but only preliminary positioning along its width. That is, after the four-anchor symmetrical anchoring coarse adjustment, the piling vessel still has a certain error in its width direction from the preset position.

[0041] In some embodiments, after coarse adjustment by symmetrical anchoring of the four anchors, fine adjustment of the positioning stakes of the moving trolley is performed. This fine adjustment includes X / Y / Z three-way adjustment via the hydraulic cylinders of the moving trolley, with an adjustment accuracy of ±1cm. Specifically, the fine adjustment of the positioning stakes of the moving trolley is mainly achieved by inserting the positioning stakes and fine-tuning the hydraulic cylinders and anchor rope lengths of the moving trolley to precisely position the piling vessel in the beam direction, ensuring the center of the cantilever fixture is located at the pre-pile position. After inserting the positioning stakes and tightening the anchor ropes of the four anchors, the piling vessel completes precise positioning.

[0042] After locating the piling vessel, the process also includes: acquiring the positioning deviation of the piling vessel, determining whether the positioning deviation is within a preset range, wherein the sampling frequency for acquiring the positioning deviation is ≥10Hz; if the positioning deviation exceeds the preset range, adjusting the positioning position of the piling vessel until the positioning deviation is within the preset range. When adjusting the positioning position of the piling vessel, adjustments can be made using any one or more positioning methods from the three-level dynamic positioning system, depending on the magnitude of the positioning deviation, until the positioning deviation is within the preset range.

[0043] In the embodiments provided in this disclosure, before performing step S1, the method further includes: providing a transport vessel, the transport vessel including a second number of pile foundations, the first number being less than the second number; the transport vessel traveling to the side of the piling vessel, the transport vessel and the piling vessel being positioned in a T-shape; and transferring the pile foundations from the transport vessel to the piling vessel using a two-point lifting method. By using a transport vessel to assist the piling vessel in transferring the pile foundations, the limitation on the number of pile foundations that the piling vessel can carry can be solved, avoiding repeated back-and-forth transfers of pile foundations by the piling vessel, thereby improving the positioning efficiency of the pile foundation group.

[0044] In some embodiments, in order to ensure the stability of the pile foundation during the transfer from the transport ship to the piling ship and to avoid damage to the pile foundation during the transfer process, a two-point lifting method can be used to transfer the pile foundation.

[0045] In some specific embodiments, when the pile foundation is made of steel piles, main lifting lugs and auxiliary lifting lugs are provided around the circumference of the pile body. Both main and auxiliary lifting lugs can be used for lifting the pile foundation. The main and auxiliary lifting lugs can be asymmetrically structured, so that after the pile foundation is positioned on the sea surface, the distance between the main lifting lugs and the sea level is less than the distance between the auxiliary lifting lugs and the sea level. The coordinated action of the main and auxiliary lifting lugs facilitates adjustments to the lifting angle and attitude of the auxiliary pile foundation. Of course, the distance between the main and auxiliary lifting lugs on the pile body and the spacing between them can be determined according to actual design requirements. When lifting the steel pile, the pile foundation can be lifted by connecting the lifting lugs with slings.

[0046] In some specific embodiments, the pile foundation can be a prestressed high-strength concrete pipe pile (PHC pile). The pile foundation is arranged within a predetermined area, with the first end fixed to the seabed and the second end protruding above the sea level. The pile body has a smooth or near-smooth structure in the circumferential direction, and the pile foundation can be a pile body structure with equal diameter, meaning that the first and second ends of the pile foundation coincide in orthographic projection on the sea level. When hoisting the PHC piles, the pile foundation can be hoisted using a binding method.

[0047] When loading pile foundations onto the transport ship, different types of pile foundations can be placed in different areas. By rationally allocating the loading areas of the transport ship, the maximum number of pile foundations can be ensured, and the pile foundations will not deform due to their placement. Specifically, when loading pile foundations onto the transport ship, they can be stacked in layers with supports between layers. PHC piles can be placed on the outer perimeter of the steel piles to ensure the rational placement of different types of pile foundations. The supports can be triangular support frames, etc., and the type of supports is not limited, as long as they can serve to separate and support the pile foundations.

[0048] After the pile foundation is loaded onto the transport ship, and the transport ship approaches the piling ship, ensure that the side positioning fixtures of the piling ship are in the retracted state. The transport ship is then moored along the length of the piling ship on the side of the piling ship. The transport ship can drop figure-eight or cross anchors on both sides of the piling ship. The anchoring distance is determined according to the soil quality, water depth, current, wind direction, and anchor weight of the anchoring area. The piling ship and the transport ship are not moored to each other. The transport ship and the piling ship are positioned in a T-shape. After the transport ship is positioned, the pile foundation is lifted from two points.

[0049] In the embodiments provided in this disclosure, in step S2, pile feeding is performed, that is, multiple pile foundations are simultaneously fed into the pile gripper of the cantilever tool using the double crane system of the pile driving vessel.

[0050] In some embodiments, the clamping force of the pile gripper is ≥1.2 times the pile weight, and the clamping pressure is evenly distributed, so as to ensure the reliability of the pile gripper in clamping the pile foundation and avoid damage to the pile foundation.

[0051] In some embodiments, when the pile gripper clamps the pile foundation, wave compensation is also enabled for the pile driving vessel, with a compensation range of ≥±1m. Due to the influence of marine environmental factors, such as the impact of waves, the position of the pile driving vessel may shift during positioning or pile driving, affecting the positioning accuracy of the pile foundation. Therefore, enabling wave compensation for the pile driving vessel can further improve the positioning accuracy of the pile foundation and enhance the stability and reliability of pile driving.

[0052] In some specific embodiments, the piling vessel is equipped with four sets of cantilever fixtures on both sides of its hull. Two cranes on board are used to lift the piles, allowing four piles to be fed at once. Specifically, a single crane can be equipped with double hooks, enabling the translation and flipping of the piles. The crane vertically lifts the piles above the pile gripper and slowly lowers them, allowing the piles to gradually sink to the seabed along the gripper. After flipping, the gripper is in the open position. Once the pile enters the gripper, the gripper is closed, the gripper pin is locked, and the lower hook is removed, completing the pile feeding process.

[0053] During the aforementioned piling process, wave compensation is activated for the piling vessel to adjust it to a horizontal position without longitudinal or transverse tilt, ensuring that the buoyancy of the piling vessel will not adversely affect the piling accuracy.

[0054] It should be noted that the cantilever fixture of the piling vessel disclosed herein is not limited to four sets. The above embodiments are merely illustrative examples. The cantilever fixture can be adaptively adjusted according to the structural design of the piling vessel and the piling requirements. That is, the cantilever fixture can realize the piling process of multiple pile foundations.

[0055] In the embodiments provided in this disclosure, in step S3, multiple pile hammers are simultaneously started to perform suspended pile driving, and a composite pile driving process combining self-sinking of piles and hammer penetration is adopted, and the pile top elevation is controlled by an elevation control system.

[0056] In some embodiments, during the self-sinking stage of pile driving, the pile driving force is controlled to be 0.2-0.5 times the ultimate bearing capacity of the pile body to avoid excessive pile driving force that could cause deformation or damage to the pile foundation.

[0057] In some embodiments, the pile sinking velocity satisfies v= Where K = 0.6-0.8, D is the pile diameter, and g is the acceleration due to gravity, this is to avoid excessively rapid pile settlement that could damage the pile foundation, and also to avoid excessively slow settlement that could reduce the pile foundation's positioning efficiency. For example, when the pile foundation is 1.5m long, the settlement velocity of the pile can be v = = =0.0437m / s.

[0058] In some embodiments, during the hammer penetration stage, the hammering energy is dynamically adjusted based on the penetration depth. The penetration depth and hammering energy can be positively correlated; that is, as the penetration depth increases, the hammering energy also increases. For example, the penetration depth δ and the hammering energy E can satisfy... Where α = 50-80 and β = 0.3-0.5, of course, depending on the different requirements of the hammer penetration process, the penetration depth δ and the hammer energy E can also be calculated using other positive correlations. The above formula is only an example. During the hammer penetration process, the longer the pile foundation penetration length, the greater the resistance it encounters. In order to ensure that the hammer energy is sufficient to overcome the pile foundation penetration resistance during the hammer penetration stage, the hammer energy is positively correlated with the pile foundation penetration depth, ensuring that the hammer energy is sufficient to drive the pile foundation into the seabed to the predetermined depth.

[0059] Due to the different types of pile foundations and the different materials used, the hammering parameters during the penetration stage vary. The pile foundation can use at least one of steel piles or PHC piles. For example, a piling vessel can simultaneously locate multiple steel piles, multiple PHC piles, or a mixture of steel and PHC piles. When a piling vessel can simultaneously locate multiple pile foundations containing a mixture of steel and PHC piles, it can locate the pile foundations according to the stacking order of the steel and PHC piles on the deck, or it can locate the pile foundations according to the stacking area of ​​the steel and PHC piles on the deck.

[0060] In some embodiments, during the driving penetration stage, the steel pile may employ a first driving mode, the parameters of which include: single hammer energy ≥ 200 kJ, and blow count ≤ 80 blows / m. During the driving penetration stage, the PHC pile may employ a second driving mode, the parameters of which include: single hammer energy ≤ 150 kJ, and blow count ≥ 120 blows / m.

[0061] In some embodiments, during the final hammer control phase, the average penetration of the last 10 blows is controlled to be ≤2mm / blow to meet the piling requirements of the final hammer phase.

[0062] In some specific embodiments, after the pile feeding is completed, two cranes on the pile driving vessel are used simultaneously to carry out suspended pile driving. Specifically, the cranes are used to lift the pile hammer, which is then slowly placed on top of the pile. The cranes gradually release the pressure, allowing the pile foundation and the pile hammer to complete the self-sinking of the pile together. When the frictional force at the pile end is balanced with the weight of the pile hammer and the pile itself, the pile foundation stops sinking, and the self-sinking of the pile is completed.

[0063] In some embodiments, during the piling process, a spirit level and measuring instruments can be used in conjunction with the hydraulic cylinder system of the mobile trolley to control the verticality of the pile body, ensuring that the pile body does not tilt significantly during the piling process.

[0064] In some embodiments, the elevation control system of the piling vessel can be used to adjust the top elevation of the pile during the piling process.

[0065] In some specific embodiments, the elevation deviation between multiple pile foundations is ≤25mm, the levelness deviation of the end face of each pile foundation is ≤0.5%, the deviation of the center distance between the pile tops of multiple pile foundations is ≤100mm, and the inclination deviation of the longitudinal axis of the pile foundation is <5‰, which meets the fixing and support requirements of the pile foundation, improves the piling stability and reliability of the pile foundation, and thus provides a structural foundation for the pile foundation to support photovoltaic modules.

[0066] In the embodiments provided in this disclosure, in step S4, after the piling is completed, the positioning pile is pulled out, and the piling vessel is anchored and moved to the next work area.

[0067] In some embodiments, the method includes: removing the positioning pile using a hydraulic buffer method; and planning the relocation path using a navigation system; wherein the relocation speed is ≤0.3 knots, and the positioning repeatability is ±5cm. The removal speed should not be too fast to avoid the piling vessel capsizing or colliding with other devices or vessels within the preset area, thereby improving the safety of the piling vessel relocation.

[0068] In some specific embodiments, after a set of four piles is driven, the positioning piles can be pulled out using a hydraulic buffer method. The positioning piles may include positioning piles of a mobile trolley and fixed positioning piles installed inside the pile driving vessel. The pulled-out positioning piles can be placed in the slots installed on the pile driving vessel for easy use next time. The pile driving vessel is then anchored and moved to the next work area. The above construction process is repeated until the pile positioning is completed.

[0069] It should be noted that before positioning multiple piles, the pile foundation positioning location and positioning parameters can be obtained through simulation. By comparing the actual positioning parameters of the pile foundation with the simulation parameters, the pile foundation positioning process can be corrected, thereby improving the positioning accuracy of the pile foundation and ensuring its reliability.

[0070] The following is combined Figure 2 The flowchart shown illustrates the construction method provided in this disclosure by taking the simultaneous positioning of four pile foundations by a single piling vessel as an example: Step S101, Construction Preparation: Use simulation to obtain the preset area for pile foundation positioning, as well as the position coordinates of each pile foundation.

[0071] Step S102, Pile loading: Load the second number of piles onto the transport ship, which can provide pile supply to the piling vessel; use the two-point method to hoist the piles onto the transport ship, and stack multiple piles in layers on the transport ship, with wooden wedges placed between layers to support the piles.

[0072] Step S103, Maritime Transportation: Transport ships may conduct maritime transportation when the wind speed at sea is no greater than level 6.

[0073] Step S104, Vessel Positioning: The transport vessel travels to the side of the piling vessel, and the transport vessel and the piling vessel are positioned in a T-shape. The side positioning fixtures of the piling vessel are in the retracted state. The transport vessel can drop V-shaped anchors on both sides of the piling vessel. The piling vessel and the transport vessel are not moored to each other.

[0074] Step S105, Pile Foundation Transfer: The pile foundation is transferred from the transport ship to the piling ship using a two-point hoisting method.

[0075] Step S106, Piling Vessel Positioning: After the piling vessel arrives at the designated location at sea, the vessel is coarsely positioned using the GPS installed on board. Anchoring is assisted by a mooring boat, and the vessel's positioning is coarsely adjusted by raising and lowering four symmetrical anchors. Cantilever fixtures are extended on both sides of the vessel. A mobile trolley pile is inserted, and by finely adjusting the trolley cylinders and anchor rope lengths, precise positioning in the beam direction is achieved, ensuring the cantilever fixture's center is positioned at the simulated design pile location. Two positioning piles are inserted, and the four anchor ropes are tightened. During the piling vessel positioning process, the simulated positioning coordinates are compared with the actual position coordinates of the piling vessel to obtain the positioning deviation. If the positioning deviation exceeds a preset range, step S106 is repeated; if the positioning deviation is within the preset range, step S107 is executed.

[0076] Step S107, Pile feeding: Use a crane to vertically lift the pile foundation to the top of the pile gripper and slowly lower it, so that the pile foundation slowly sinks to the seabed along the pile gripper; after the pile is turned over, the clamp is in the open state. After the pile foundation enters the clamp, close the clamp, lock the clamp pin, and remove the lower hook.

[0077] Step S108, Suspended Pile Driving: Use a crane to lift the pile hammer and slowly place it on top of the pile. Gradually release the pressure from the crane so that the pile foundation and the pile hammer can complete the self-sinking of the pile together. When the frictional force at the pile end is balanced with the weight of the pile hammer and the pile foundation itself, the pile foundation will stop sinking and the self-sinking of the pile will be completed. After the sinking is completed and the pile hammer and the pile body are in a stable state, the pile driving operation will be carried out. During the pile driving process, the elevation of the pile top will be controlled by the elevation control system.

[0078] Step S109, Anchoring and Moving the Ship: After driving a set of pile foundations, pull out the mobile trolley positioning piles and the fixed positioning piles, and anchor and move the ship to the next work area.

[0079] The piling vessel positioning method disclosed herein can simultaneously position four pile foundations. Compared with the traditional construction method of positioning each pile foundation one by one, the piling vessel positioning method saves more than 60% of the time and reduces the positioning time by more than 70% for the same number of pile foundations, effectively improving the efficiency of pile foundation positioning construction.

[0080] It should be noted that although the steps of the offshore photovoltaic multi-pile synchronous positioning construction method of this disclosure are described in a specific order in the accompanying drawings, this does not require or imply that these steps must be performed in that specific order, or that all the steps shown must be performed to achieve the desired result. Additional or alternative steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0081] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A method for synchronous positioning and construction of multiple offshore photovoltaic piles, characterized in that, The piling vessel includes a dual-crane system, multiple cantilever fixtures mounted on both sides of the hull, and a mobile trolley, including: Step S1: The piling vessel travels to the preset area and performs three-level dynamic positioning on the piling vessel, which carries a first number of piles; wherein, the three-level dynamic positioning includes GPS coarse positioning, four-anchor symmetrical anchoring coarse adjustment and positioning pile fine adjustment by the mobile trolley. Step S2: Using the dual crane system of the piling vessel, multiple pile foundations are simultaneously fed into the pile gripper of the cantilever tool; Step S3: Simultaneously start multiple pile hammers for suspended pile driving, adopting a composite pile driving process that combines self-sinking of piles with hammer penetration, and adjust the pile top elevation through an elevation control system. Step S4: After completing the piling, pull out the positioning pile, and the piling vessel is anchored and moved to the next work area.

2. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 1, characterized in that, Before step S1, the following is also included: Provide a transport vessel, the transport vessel comprising a second number of pile foundations, the first number being less than the second number; The transport vessel travels to the side of the piling vessel, and the transport vessel and the piling vessel are positioned in a T-shape. The pile foundation is transferred from the transport ship to the piling ship using a two-point lifting method.

3. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 2, characterized in that, When the pile foundations are loaded onto the transport ship, they are stacked in layers with cross stacking and support components between the layers. Different types of pile foundations are loaded in different areas.

4. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 1, characterized in that, In step S1, The coarse adjustment of the four-anchor symmetrical anchoring includes: the anchoring angle of the four anchors is ±30° to 45° of the bow and stern line of the piling vessel, and the anchor rope length is ≥ 4 times the water depth; Fine-tuning of the mobile trolley includes: X / Y / Z three-way adjustment via the hydraulic cylinders of the mobile trolley, with an adjustment accuracy of ±1cm.

5. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 4, characterized in that, The method further includes: The positioning deviation of the piling vessel is obtained, and it is determined whether the positioning deviation is within a preset range, wherein the sampling frequency for obtaining the positioning deviation is ≥10Hz; If the positioning deviation exceeds the preset range, the positioning position of the piling vessel is adjusted until the positioning deviation is within the preset range.

6. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 1, characterized in that, In step S2, The clamping force of the pile gripper is ≥1.2 times the pile weight, and the clamping pressure is evenly distributed; Step S2 also includes: enabling wave compensation for the piling vessel, with a compensation range of ≥±1m.

7. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 1, characterized in that, In step 3, During the self-sinking stage of pile driving, the pile driving force is controlled at 0.2-0.5 times the ultimate bearing capacity of the pile. The sinking speed of the pile body satisfies v= Where K = 0.6-0.8, D is the pile diameter, and g is the acceleration due to gravity; During the hammering penetration stage, the hammering energy is dynamically adjusted by the penetration degree, and the penetration degree is positively correlated with the hammering energy. During the final hammer control phase, the average penetration of the last 10 blows is controlled to be ≤2mm / blow.

8. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 7, characterized in that, After step S3, The elevation deviation between multiple pile foundations is ≤25mm, the levelness deviation of the end face of each pile foundation is ≤0.5%, the deviation of the center distance between the pile tops of multiple pile foundations is ≤100mm, and the inclination deviation of the longitudinal axis of the pile foundation is <5‰.

9. The method for synchronous positioning and construction of multiple offshore photovoltaic piles according to claim 1, characterized in that, Step S4 includes: The positioning pile was pulled out using a hydraulic buffer-type pile extraction method; A navigation system is used to plan the ship's movement path; the ship's movement speed is ≤0.3 knots, and the positioning repeatability is ±5cm.

10. The method for synchronous positioning and construction of multi-pile marine photovoltaic systems according to any one of claims 1-9, characterized in that, The pile foundation includes at least one of steel piles or PHC piles; During the hammer penetration stage, the steel pile adopts the first hammer driving mode, the parameters of which include: single hammer energy ≥ 200kJ, number of blows ≤ 80 blows / m; the PHC pile adopts the second hammer driving mode, the parameters of which include: single hammer energy ≤ 150kJ, number of blows ≥ 120 blows / m.

Images