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CN-117684532-B - Portal type platform for large-scale offshore wind turbine and construction method

CN117684532BCN 117684532 BCN117684532 BCN 117684532BCN-117684532-B

Abstract

A portal platform for a large offshore wind turbine and a construction method thereof, comprising at least three tubular legs and a horizontal deck, wherein no horizontal or diagonal support members are arranged between the tubular legs, and the horizontal deck comprises at least three circular sleeves. The portal platform is in an on-site power generation mode for supporting a draught fan, the tops of tubular legs are concentrically connected with a horizontal deck above a waterline and vertically extend downwards to a seabed, the portal platform is provided with a temporary floating installation mode, two barges are connected to two sides of the horizontal deck above the waterline for supporting the draught fan, the bottoms of the tubular legs are concentrically arranged in a circular sleeve and vertically extend upwards, the construction method is used for assembling the portal platform and a foundation pile on a wharf shore and integrating with the draught fan, towing and self-installing on the whole sea, and the tubular legs are lowered and extended to the seabed through the circular sleeve by using cables and winch systems arranged on two barges to finish the conversion of the portal platform from the floating installation mode to the on-site power generation mode.

Inventors

  • WANG JIN

Assignees

  • 上海交通大学

Dates

Publication Date
20260512
Application Date
20230906
Priority Date
20220909

Claims (12)

  1. 1. A portal platform, comprising: A plurality of vertically disposed elongate tubular legs including an upper section, a middle section, and a lower section; A horizontal deck comprising a plurality of circular sleeves radially equidistant from a center thereof, a base structure at a center thereof, and a plurality of horizontal beams, each horizontal beam being connected at one end to a corresponding circular sleeve and at another end to the base structure, an inner diameter of the circular sleeve being greater than an outer diameter of the elongated tubular legs, each elongated tubular leg being concentrically located within the corresponding circular sleeve with an annular space therebetween; a wind turbine system comprising a wind tower vertically connected at the bottom to a base structure of a horizontal deck, a nacelle connected to the top of the wind tower, and a plurality of rotor blades connected to the nacelle; the top of each foundation pile is vertically connected with the bottom of the corresponding extension tubular leg, wherein the foundation pile is a suction caisson pile, and the diameter of the foundation pile is larger than that of the extension tubular leg; the two ends of the foundation pile connecting rods are horizontally connected with the tops of the two foundation piles; a plurality of lateral guides, one end of which is horizontally connected to the top of a corresponding elongated tubular leg; When the portal platform is positioned in the offshore wind farm water and is in an in-place power generation mode, more than half of the length of the elongated tubular legs vertically extend downwards to the seabed below the waterline, no horizontal or diagonal supporting members are arranged between the elongated tubular legs, the horizontal decks are positioned above the waterline, the upper sections of the elongated tubular legs are concentrically positioned inside the circular sleeves of the corresponding horizontal decks and are rigidly connected, the bottom of a wind tower of the fan system is vertically connected with a base structure of the horizontal decks, foundation piles are embedded in the seabed, and the upper ends of the foundation piles are positioned above the seabed and are vertically and rigidly connected with the lower sections of the elongated tubular legs; When the portal platform is positioned in shallow water on the quay side and in a quay assembling mode, more than half of the length of the extension tubular legs vertically extend upwards to the air above the waterline, no horizontal or diagonal supporting members are arranged between the extension tubular legs, the horizontal decks are positioned above the waterline, the lower sections of the extension tubular legs are concentrically positioned inside the circular sleeves of the corresponding horizontal decks, the bottoms of wind towers of the fan system are vertically connected with the base structures of the horizontal decks, foundation piles vertically stand on the seabed, and the upper ends of the foundation piles are positioned above the waterline and are vertically and rigidly connected with the lower sections of the extension tubular legs; When the portal platform is in a floating installation mode, towing and offshore installation are realized through a catamaran floating system consisting of two floating barges, wherein a horizontal deck is positioned above a water line, the two floating barges are rigidly connected on two opposite sides to form the catamaran floating system, more than half of the length of an elongated tubular leg vertically extends upwards to the air above the water line, no horizontal or diagonal supporting members are arranged between the elongated tubular legs, the lower sections of the elongated tubular legs are concentrically positioned inside circular sleeves of the corresponding horizontal decks, the bottoms of wind towers of the fan systems are vertically connected with the base structures of the horizontal decks, the upper ends of foundation piles are positioned above the water line and vertically rigidly connected with the lower sections of the elongated tubular legs, and the lower ends of the foundation piles are positioned above the sea floor.
  2. 2. The portal platform of claim 1, wherein there is a concentric annular space between the outside of the upper section of each elongate tubular leg and the inside of the corresponding circular sleeve of the horizontal deck, the rigid connection being made by cementing; each circular sleeve includes a circular housing, a plurality of inner guide units are vertically connected to the inside of the circular housing, and an inner annular plate is horizontally connected to the inside of the lower end of the circular housing, the inner diameter of the inner annular plate being matched with the diameter of the circle formed by the inner guide units.
  3. 3. The portal platform of claim 1 wherein the upper section of the elongate tubular leg comprises a circular shell having a diameter equal to the outer diameter of the upper section thereof, a plurality of external guide units attached to the outside of the circular shell, an outer annular plate attached horizontally to the bottom of the circular shell, and a watertight cover attached to the top of the circular shell, wherein the vertical distance from the bottom outer annular plate to the watertight cover matches the height of the circular sleeve of the horizontal deck; The inner diameter of the inner annular plate of the circular sleeve is larger than the outer diameter of the upper section of the extension tubular leg with the outer guide unit, wherein the extension tubular leg vertically penetrates through the opening of the inner annular plate of the circular sleeve to extend downwards until the outer annular plate of the upper section contacts with the inner annular plate of the circular sleeve, and the size of the outer annular plate of the upper section is matched with that of the inner annular plate of the circular sleeve; The diameter of the circular casing of the circular sleeve is larger than that of the circular casing of the upper section of the elongated tubular leg, an annular space is formed between the circular casing of the circular sleeve and the circular casing of the upper section of the elongated tubular leg, cement grouting is filled in the annular space, and a rigid connection is formed between the circular sleeve of the horizontal deck and the upper section of the elongated tubular leg.
  4. 4. The portal platform of claim 1 wherein the rigid connection between the upper sections of the elongated tubular legs and the horizontal deck is bolted, comprising a plurality of steel bolts connecting respective portions of the upper sections of each elongated tubular leg to the circular sleeves and horizontal beams of the corresponding horizontal deck, wherein the upper sections of the elongated tubular legs comprise an upper portion comprised of a top horizontally extending plate, vertical webs and vertical side plates, and a lower portion comprised of a circular outer shell having a diameter equal to the diameter of the upper sections of the elongated tubular legs, an outer annular plate, a watertight cover plate and a plurality of external guide units connected horizontally to the top of the circular outer shell, the plurality of external guide units connected to the outside of the circular outer shell.
  5. 5. The portal platform of claim 1, wherein each circular sleeve of the horizontal deck comprises a circular outer shell having a diameter and height matching the height of the upper portion of the upper section of the elongated tubular leg, a T-shaped member and a plurality of internal guide units vertically attached to the inside of the circular outer shell, an inner annular plate horizontally attached to the lower end of the circular outer shell, wherein the inner annular plate has an inner diameter equal to the diameter of the circle formed by the T-shaped member and the internal guide units, the circular outer shell being attached to the top flange plate, the vertical web and the bottom flange plate of the horizontal beam of the horizontal deck; The top flange plate of the horizontal beam of the horizontal deck is connected with the horizontal extension plate at the top of the upper section of the extension tubular leg through bolts, and the T-shaped member and the inner annular plate of the circular sleeve of the horizontal deck are respectively connected with the vertical side plate and the outer annular plate of the upper section of the extension tubular leg through bolts.
  6. 6. Portal platform according to claim 1, characterized in that the dock assembly modality comprises at least three lateral guides, wherein one end of each lateral guide is connected to the top of a corresponding elongated tubular leg and the other end is in contact with the wind tower; The transverse guiding device comprises a shell structure, a hydraulic cylinder connected with the shell structure and capable of adjusting the length, and a spring unit, one end of the spring unit is connected to the hydraulic cylinder, the other end of the spring unit is contacted with the wind tower under the action of pressure, and the length of the spring unit changes along with the change of the pressure.
  7. 7. Portal platform according to claim 1, characterized in that each of the two floats floating barge is provided with at least one deck support structure and a set of cables and winch systems, wherein the deck support structure is connected at one end to the top of the floating barge and at the other end to the horizontal deck, wherein the deck support structure is provided with a quick release device with a mechanism for separating the floating barge from the horizontal deck within a few seconds; the cable and winch system consists of a winch and a cable, wherein one end of the cable is connected to the winch at the top of the floating barge, extending down through a pulley connected to a horizontal deck to the other end to an ear plate at the top of the foundation pile.
  8. 8. The construction method of the portal platform is characterized in that the portal platform comprises the following steps: a plurality of vertically extending elongate tubular legs, the elongate tubular legs comprising an upper section, a middle section and a lower section; a horizontal deck comprises a plurality of circular sleeves arranged radially equidistant from the center, A centrally located base structure and a plurality of horizontal beams, each horizontal beam connected at one end to the base structure and at the other end to a corresponding circular sleeve, wherein the diameter of the circular sleeve is greater than the diameter of the elongate tubular leg; a fan system including a wind tower, a nacelle, and a plurality of rotor blades; a plurality of suction caisson foundation piles; a plurality of foundation pile connecting rods; A plurality of lateral guides; the construction method comprises the following steps: Step 1, horizontally connecting the tops of a plurality of suction caisson foundation piles erected on land through a plurality of foundation pile connecting rods to form a symmetrical foundation pile sub-assembly, hoisting the foundation pile sub-assembly into water on the quay side to enable the foundation pile sub-assembly to stand on the sea floor, wherein the tops of the foundation pile sub-assemblies are higher than a waterline; Step 2, hoisting horizontal decks to the top of foundation pile subassemblies erected on the seabed, wherein a circular sleeve of each horizontal deck is directly positioned on a corresponding suction caisson foundation pile, a base structure of each horizontal deck is positioned in the center of symmetrical arrangement, and the horizontal decks are temporarily connected with the foundation pile subassemblies through a plurality of marine fasteners above water lines; Step 3, vertically hoisting at least one elongated tubular leg onto the top of the foundation pile subassembly through at least one circular sleeve on the horizontal deck distal to the quay, rigidly connecting the bottom of the elongated tubular leg to the top of the suction caisson foundation pile distal to the quay, wherein the means of rigid connection comprises welding or cementing connection; step4, vertically hoisting the wind tower, and rigidly connecting the bottom of the wind tower to the top of the base structure of the horizontal deck, wherein the rigid connection mode comprises welding or bolting; Step 5, vertically hoisting at least one elongated tubular leg onto the top of the foundation pile subassembly through at least one circular sleeve on the horizontal deck off the dockside, rigidly connecting the bottom of the elongated tubular leg to the top of the suction caisson foundation pile on the off-dockside, where the means of rigid connection include welding or cementing connections; And 6, installing a transverse guiding device on the top of each corresponding extension tubular leg, hoisting and connecting the nacelle to the top of the wind tower, hoisting and connecting the rotor blades to the nacelle, completing the wharf assembly mode of the portal platform, and integrating the portal platform, the fan system and the suction caisson foundation pile into a platform integral system, wherein the platform integral system is in a fixed standing state.
  9. 9. The method of constructing according to claim 8 wherein the portal platform further comprises a plurality of pulleys coupled to the horizontal deck, a plurality of ear plates coupled to the tops of the corresponding suction caisson foundation piles and the two floating barges, wherein a plurality of deck support structures are coupled to the tops of each floating barge, a plurality of quick disconnect devices are coupled to each corresponding deck support structure, and a plurality of sets of cable and winch systems; the construction method further comprises the following steps after the step 6: Step 7, rigidly connecting two floating barges to corresponding two sides of a horizontal deck to form a catamaran system, and changing the platform overall system from a fixed standing state to a floating state, namely a floating installation mode, by reducing ballast water of the floating barges, wherein the catamaran system provides buoyancy and stability for the floating installation mode formed by a portal platform on the quay shore, and wherein the two floating barges are provided with deck support structures and cables and winch systems, by connecting one end of each of the deck support structures to the horizontal deck by a quick disconnect device, and simultaneously, each cable extends downwards from one end of a winch through a pulley connected to the horizontal deck to the other end of an ear plate positioned at the top of each foundation pile, thereby completing the floating installation mode of the platform overall system integrated with the fan system and the suction caisson foundation pile; step 8, towing a platform integral system of a portal platform with a fan system and suction caisson foundation piles in a floating installation mode from an assembly dock to an offshore wind farm by using a tugboat, wherein two floating barges are connected to opposite sides of a horizontal deck to provide buoyancy and stability during offshore towing; Step 9, converting the platform integral system of the portal platform with the fan system and the suction caisson foundation pile from a floating installation mode to an in-place power generation mode by adopting a self-installation process, wherein the self-installation process comprises the steps of disconnecting a marine fastener between a horizontal deck above a waterline and the suction caisson foundation pile, enabling an elongated tubular leg to move downwards through a circular sleeve of the horizontal deck under the action of self gravity, controlling the lowering movement speed by using a cable and winch system, and simultaneously, keeping a transverse guide device which moves downwards together with the elongated tubular leg in pressure contact with a wind tower all the time to provide horizontal transverse support for the elongated tubular leg in the self-installation process, and providing buoyancy and stability for the platform integral system by two floating barges connected to two opposite sides of the horizontal deck; Step 10, further lowering the elongated tubular legs through a cable and winch system until the suction caisson foundation pile is lowered onto the seabed; step 11, embedding suction caisson foundation piles into the seabed through suction, wherein the upper section of each elongated tubular leg is concentrically positioned in a corresponding circular sleeve of the horizontal deck, and an annular space is formed between the upper section and the circular sleeve; In step 12, a rigid connection is made between the upper section of the elongate tubular leg and the circular sleeve of the horizontal deck by filling the annular space with grout and disconnecting the two floating barges from the horizontal deck and pulling the two floating barges apart by activating the quick disconnect.
  10. 10. A portal platform, comprising: A plurality of vertically disposed elongate tubular legs including an upper section, a middle section, and a lower section; A horizontal deck comprising a plurality of circular sleeves radially equidistant from the center, a centrally located base structure and a plurality of horizontal beams, wherein each horizontal beam is connected at one end to a corresponding circular sleeve and at the other end to the base structure, the circular sleeves having an inner diameter greater than an outer diameter of the elongated tubular legs, each elongated tubular leg being concentrically located within a corresponding circular sleeve with an annular space therebetween; A wind turbine system comprising a wind tower vertically connected at the bottom to a base structure of a horizontal deck, a nacelle connected to the top of the wind tower, and a plurality of rotor blades connected to the nacelle; the plurality of driven piles are specifically round pipe bodies; The connecting transition sections are in particular circular pipe bodies which are concentrically or eccentrically connected to the lower sections of the corresponding elongated tubular legs; the anti-sinking plates are horizontally connected to the bottoms of the corresponding connecting transition sections; A plurality of lateral guides, one end of which is horizontally connected to the top of a corresponding elongate tubular leg; When the portal platform is positioned in shallow water on the quay side and is in a quay assembling mode, more than half of the length of the extension tubular legs vertically extend upwards to the air above the water line, no horizontal or diagonal supporting members are arranged between the extension tubular legs, the horizontal decks are positioned above the water line, the lower sections of the extension tubular legs are concentrically positioned inside the circular sleeves of the corresponding horizontal decks, the bottom of a wind tower of the fan system is vertically connected with the base structure of the horizontal decks, the connecting transition section and the anti-sinking plate positioned below the connecting transition section are vertically standing on the seabed, and the upper ends of the connecting transition section and the anti-sinking plate are vertically and rigidly connected with the lower sections of the extension tubular legs and are simultaneously connected with the horizontal decks through temporary fasteners; When the portal platform is positioned in the water of the offshore wind farm and is in an in-place power generation mode, more than half of the length of the elongated tubular legs vertically extend downwards to the seabed below the waterline, no horizontal or diagonal supporting members are arranged between the elongated tubular legs, the horizontal decks are positioned above the waterline, the upper sections of the elongated tubular legs are concentrically positioned inside the circular sleeves of the corresponding horizontal decks and are rigidly connected, the bottom of a wind tower of the fan system is vertically connected with a base structure of the horizontal decks, the lower parts of the driving piles are embedded into the seabed, and the upper parts of the driving piles positioned above the seabed are concentrically and vertically rigidly connected with the connecting transition sections.
  11. 11. Portal platform according to claim 10, characterized in that when the portal platform is in a floating installation mode, towing and marine installation is achieved by a catamaran floating system consisting of two floating barges, wherein the horizontal deck is located above the water line and rigidly connected to the two floating barges on opposite sides to form a catamaran floating system, the elongate tubular legs extending vertically upwards to the air above the water line for more than half the length thereof, there being no horizontal or diagonal support members between the elongate tubular legs, the lower sections of the elongate tubular legs being concentrically located inside the circular sleeves of the corresponding horizontal deck, the bottom of the wind towers of the fan system being vertically connected to the base structures of the horizontal deck, the upper ends of the connection transition sections being located above the water line and being vertically rigidly connected to the lower sections of the elongate tubular legs, the lower ends of which are located above the sea floor and being horizontally connected to the anti-sinking plate, wherein each of the two floating floating barge boats is provided with at least one deck support structure and a quick-release device and at least one set of cable and winch system, the sea piles being pre-installed on the sea bottom of the offshore wind farm, the wind farm having an inner diameter smaller than the inner diameter of the connection section being vertically connected to the base structure of the horizontal deck, the plurality of shear keys being connected to the inner sides of the circular key connection sections.
  12. 12. Portal platform according to claim 10, characterized in that when the portal platform is in a self-installation procedure, the lower sections of the elongated tubular legs each with a connection transition section and a horizontal anti-sinking plate are lowered and concentrically docked with the upper part of the corresponding driven pile pre-installed on the sea floor using a cable and winch system, the connection transition section is rigidly connected with the driven pile upper part by cementing, and then the upper section of each elongated tubular leg is rigidly connected with the corresponding circular sleeve of the horizontal deck by cementing or bolting, in the self-installation procedure, the two floating barges are rigidly connected with both sides of the horizontal deck by deck support structures and quick release means, providing buoyancy and stability to the portal platform, and finally, the quick release means are activated to disconnect the two floating barges from the horizontal deck, completing the transition of the portal platform from the floating installation mode to the in-place power generation mode.

Description

Portal type platform for large-scale offshore wind turbine and construction method The application requests priority of application No. US17/941,775 of Portal platform and construction method for Large offshore wind turbines (PORTAL FRAME PLATFORM AND CONSTRUCTION METHOD FOR LARGE OFFSHORE WIND TURBINES) under the name of 2022, 9 and 9. Technical Field The invention relates to a technology in the field of ocean engineering structures, in particular to a portal type platform for a large-scale offshore wind turbine and a construction method. Background Currently, most offshore wind turbines that have been installed are located in sea areas with water depths of less than 30 meters, with power generation capacities typically less than 10 megawatts, supported by a stationary foundation structure. As demand for offshore wind power increases, there is an increasing trend to deploy large fans with power generation capacity greater than 10 megawatts in sea areas with water depths exceeding 30 meters. The existing single pile and jacket foundation technology has the defects that the current offshore wind power industry faces serious bottleneck problems such as high cost, complex offshore installation, long project period and the like when the water depth exceeds 30 meters to deploy a large-scale fan. In order to reduce costs and improve project progress, there is an urgent need for a new infrastructure that is efficient and cost effective and installation method that does not require the use of large crane installation vessels. Disclosure of Invention Aiming at the defects in the prior art, the invention provides a portal type platform for a large-scale offshore wind turbine and a construction method thereof, which can be assembled at a wharf and integrated with a wind turbine system, integrally towed and automatically installed without using a large-scale hoisting installation ship, thereby overcoming the problems of the existing single pile and jacket foundation. The portal platform includes at least three elongated tubular legs extending vertically downward from the top above the waterline to the seabed without horizontal or diagonal members in the middle and a horizontal deck including at least three circular sleeves concentrically connected to the top of the elongated tubular legs for supporting the fan system in an in-situ power generation mode. Wherein the wind turbine system comprises a wind turbine tower having a bottom vertically connected to the center of the horizontal deck above the water line and a top connected to the nacelle and rotor blades. The bottom of each elongate tubular leg is connected to a foundation pile embedded in the seabed. The invention is realized by the following technical scheme: The invention relates to a portal platform for a large offshore wind turbine, comprising four vertical elongated tubular legs, each leg being located at one corner of a square pattern, four foundation piles, the upper end of each pile being connected to the bottom of each elongated tubular leg. A horizontal deck includes four circular sleeves equidistant from the geometric center, wherein each circular sleeve is concentrically connected to the top of each elongated tubular leg, a base structure at the geometric center of the horizontal deck is vertically connected to the bottom of the wind turbine tower, and four horizontal beams radially connect the base structure and the circular sleeves. The circular sleeve includes a circular housing having a height matched with that of the horizontal beam, a plurality of inner guide units vertically connected inside the circular housing and uniformly and symmetrically arranged, and an inner annular plate horizontally connected to a lower end of the circular housing, wherein an inner diameter of the inner annular plate is approximately equal to a diameter of a circle formed by the inner guide units. Each of the elongated tubular legs comprises an upper section (upper part), a lower section (lower part) and a middle section (middle part), wherein the upper section comprises a top watertight cover plate, a circular pipe body, a plurality of external guide units vertically connected to the outer side of the circular shell and uniformly and symmetrically arranged, and an outer annular plate horizontally connected to the circular pipe body, the outer annular plate is positioned below the top watertight cover plate, and the vertical distance of the outer annular plate is matched with the diameter of the circular sleeve. The outer annular plate of the upper section of each elongate tubular leg has a size that matches the size of the inner annular plate of the circular sleeve. The inner annular plate shape of the circular sleeve of the horizontal deck has an inner diameter at least 1 inch larger than the outer diameter of the elongated tubular legs with the outer guide units, wherein the elongated tubular legs are movable vertically up and down within the circular sleeve concen