A prestressed hollow sandwich steel tube concrete lattice hybrid jacket

Abstract

The present invention discloses a prestressed hollow sandwich steel tube concrete lattice hybrid conductor frame, which relates to the field of offshore wind power generation technology. The system consists of a wind turbine, a steel tower, a switching device, a lattice conductor frame and steel piles. The corner columns of the lattice conductor frame are connected to the steel piles by flanges; the switching device is arranged on the top of the conductor frame; the steel tower and the upper part of the switching device are connected by flanges; the wind turbine is arranged on the steel tower; the lattice conductor frame can be triangular or quadrilateral, and the corner columns are all made of prestressed hollow sandwich steel tube concrete; the diagonal rods in the lattice conductor frame are made of ordinary steel pipes, and the cross nodes are poured with concrete. The main components of the lattice conductor frame are made of hollow sandwich steel tube concrete and ordinary steel pipes, which reduces the amount of steel and concrete, and applies continuous prestressing to the main supporting rods, which can improve the tensile performance of the structure and prevent concrete cracking. It is a new form of offshore wind power conductor frame.

Description

Technical Field

[0001] The present invention relates to the technical field of offshore wind power generation. Background Art

[0002] Wind power, as a clean energy source, has garnered worldwide attention in recent years. Offshore wind power offers significant advantages over conventional wind power, including higher wind speeds, more stable operation, and longer availability. Furthermore, offshore wind farms are located near densely populated large and medium-sized cities with high electricity demand, making them a promising new market for the wind power industry with enormous potential.

[0003] Jacket-type wind turbine foundations are currently a common foundation type for offshore wind turbine structures, suitable for large wind turbines and deep-sea applications. During operation, offshore wind turbine foundations bear not only hydrodynamic loads, but also the long-term effects of aerodynamic loads on the wind turbines. Frequent alternating stresses within the structure can cause fatigue damage to the joints. Traditional jackets often utilize lattice-type steel pipe jackets, which require high positioning and horizontal precision and are difficult to level. On-site assembly, grouting, and hoisting cycles are lengthy, and underwater grouting quality requirements are high, making control of construction processes and design parameters challenging.

[0004] Therefore, in order to effectively utilize my country's abundant offshore wind power resources, streamline project implementation procedures and processes, improve construction quality, shorten installation and construction time, and reduce fatigue damage at nodes, it is necessary to improve the structural form of traditional jackets and develop a jacket form with the best performance, cost and quality. Summary of the Invention

[0005] The present invention comprehensively proposes a prestressed hollow sandwich steel tube concrete lattice hybrid conductor frame: the upper part is a steel tower, and the lower part is a lattice conductor frame, which reduces the size of the components while significantly reducing the wind load and wave load on the conductor frame. The rods in the lattice conductor frame mainly bear the axial force, giving full play to the strength of the material. The corner columns of the lattice conductor frame adopt prestressed hollow sandwich steel tube concrete, which increases the rigidity while reducing the amount of steel and concrete, reducing the weight of each component, and facilitating transportation and lifting. The sandwich concrete part is provided with pre-tensioned prestressed tendons, which are tensioned along the entire height to increase the stability and tensile resistance of the structure. The oblique support components adopt cross-node cast concrete steel pipes to improve the fatigue performance at the nodes. It has a simple structural structure and good vertical and overall stability. It is a new type of wind turbine conductor frame. The entire structural system adopts an assembled construction method, and each component is produced in a standardized manner in the project or on site, which significantly improves construction efficiency, ensures construction quality, and reduces the cost of construction measures.

[0006] The technical solutions of the present invention are as follows:

[0007] A prestressed hollow sandwich steel tube concrete lattice hybrid jacket structure comprises a wind turbine, a steel tower, a connecting device, a lattice jacket, and steel piles. The steel piles are pre-positioned and sunk, with stiffening flanges on top. The corner columns of the lattice jacket are bolted to the steel piles. The top of the lattice jacket is connected to the connecting device, the connecting device is connected to the steel tower, and the steel tower is connected to the wind turbine.

[0008] The corner columns of the lattice-type jacket are constructed with prestressed hollow sandwich steel tubular concrete, with prestressed tendons arranged in the sandwich concrete. The diagonal bars are constructed of ordinary steel tubes, with concrete poured at the intersections. Holes are drilled at the ends of the diagonal bars and connected to the steel tubes in the corner columns. Perforated ring diaphragms and longitudinal stiffening ribs are installed at the connection points, and the prestressed tendons pass through the holes.

[0009] The adapter is a conical composite shell. It is prefabricated in the factory and consists of an outer steel plate, an inner steel plate, and concrete. Studs are welded at regular intervals on the inner and outer sides of the outer and inner steel plates, and then concrete is poured. Either ordinary concrete or lightweight aggregate concrete can be used. Flanges connect the adapter to the tower and jacket, respectively, at the top and bottom.

[0010] The present invention has the following beneficial effects compared to the prior art:

[0011] (1) The jacket and steel piles are connected by multi-gasket flanges, which can adjust the horizontal deviation caused by pile sinking and improve on-site construction efficiency.

[0012] (2) All components are prefabricated in the factory and assembled directly on site, which significantly improves construction efficiency, ensures construction quality, and reduces construction costs. All connections between components are dry-type, which simplifies the construction process, shortens the construction period, and reduces environmental pollution.

[0013] (3) Each member in the lattice-type jacket adopts standardized dimensions to improve production and processing efficiency. The structure is simple and easy to install. Prestressed hollow sandwich steel tube concrete is used. The prestressing forces the entire cross-section of the steel tube concrete to be compressed. The steel tube forms a constraint effect on the concrete, improving the strength and ductility of the concrete. Partial concrete is poured at the intersection, which can effectively improve the fatigue performance of the node and extend the fatigue life. At the same time, the increase in deadweight is small, saving materials.

[0014] (4) The prestressed tendons are tensioned using the pre-tensioning method, which does not require anchors and improves on-site construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is an overall schematic diagram of the present invention;

[0016] Figure 2 This is a schematic diagram of a multi-gasket flange connection;

[0017] Figure 3 This is a schematic diagram of a lattice-type jacket;

[0018] Figure 4 It is a schematic diagram of the cross node of the diagonal rod;

[0019] Figure 5 This is a schematic diagram of the corner column connection node;

[0020] Figure 6 Schematic diagram of the ring diaphragm;

[0021] Figure 7 Schematic diagram of the switching device;

[0022] In the figure: 1-wind turbine, 2-steel tower, 3-transfer device, 4-lattice jacket, 5-steel pile, 6-corner column, 7-diagonal rod, 10-gasket, 11-prestressed tendon, 13-annular diaphragm, 14-inner steel pipe, 15-outer steel pipe, 16-inner steel plate, 17-outer steel plate, 20-corbel. DETAILED DESCRIPTION

[0023] The present invention will be further described below with reference to the accompanying drawings.

[0024] like Figure 1 As shown, a prestressed hollow sandwich steel tube concrete lattice hybrid conductor frame relates to the field of offshore wind power generation technology. The system includes a wind turbine (1), a steel tower (2), a switching device (3), a lattice conductor frame (4), and steel piles (5). The steel piles (5) are pre-positioned and sunk; the corner columns (6) in the lattice conductor frame (4) are connected to the steel piles (5), and the lattice conductor frame can be designed as a quadrilateral lattice conductor frame or a triangular lattice conductor frame; the switching device (3) is connected to the lattice conductor frame (4); the lower end of the steel tower (2) is connected to the switching device (3); the wind turbine (1) is arranged at the upper end of the steel tower (2);

[0025] like Figure 2 As shown, after the steel pile (5) is positioned and sunk, flanges are respectively provided at the top of the steel pile (5) and the bottom of the corner column (6), and four stiffening ribs are provided. A plurality of gaskets (10) with a thickness of 0.1 to 2 mm are provided in the middle of the flanges, and screws pass through the gaskets to connect the corner column (6) of the lattice-type jacket (4) and the steel pile (5).

[0026] like Figure 3 As shown, the lattice-type jacket (4) is composed of corner columns (6) and diagonal rods (7). The steel pipes are all purchased as finished threaded steel pipes. The steel strength grades are Q390, Q420, and Q460, the concrete strength grades are C50 to C80, and the steel pipe thickness is 8 to 16 mm. The corner columns are all perpendicular to the ground. The diameter of the bottom corner column is 1 m to 1.5 m. The diameter and thickness of the steel pipe gradually decrease as the height increases.

[0027] like Figure 4 As shown, the diagonal rods (7) in the lattice-type jacket (4) are made of ordinary steel pipes, and the cross nodes are partially poured with concrete, the length of which is 3 to 5 times the diameter of the diagonal rod (7). Holes are opened at the ends of the diagonal rods, and prestressed tendons (11) pass through the holes.

[0028] like Figure 5 As shown, the corner columns (6) in the lattice-type jacket (4) are made of prestressed hollow sandwich steel tube concrete. The outer steel tube (15) has a hole, and the diagonal rod (7) passes through the hole and extends into the interior of the corner column (6) to connect with the inner steel tube (14). Two ring partitions (13) are arranged above and below the connection node.

[0029] like Figure 6 As shown, the annular partition (13) is evenly arranged with 6 to 10 holes and 6 to 10 stiffening ribs along the annular direction, the prestressed tendons pass through the annular partition (13) and the holes at the ends of the diagonal rod (7), and the prestressed tendons (11) are arranged along the entire length.

[0030] like Figure 7 As shown, the adapter (3) is composed of an outer steel plate (17), an inner steel plate (16) and concrete. Studs are welded at a certain interval on the inner side of the outer steel plate (17) and the outer side of the inner steel plate (16), and then concrete is poured. Two stiffening ribs are set on the upper part of the corner column (6) of the lattice-type jacket (4), and are connected to the lower part of the adapter (3) by screws. The upper part of the adapter (3) is flange-connected to the lower part of the steel tower (2), and the screws extend into the lower part of the bracket (20) in the adapter (3).

[0031] The specific production and installation methods are as follows:

[0032] Prefabricate steel piles (5) in the factory, purchase spiral steel pipe products and complete the welding work of the adapter (3), diagonal rods (7), flanges, stiffening ribs, annular partitions (13) and bolts; complete the tensioning and fixing of the prestressed tendons (11) in the factory, then pour the hollow sandwich steel tube concrete and diagonal rod (7) components, and complete the production of the corner columns (6) and diagonal rods (7) in the lattice-type jacket (4); after the steel piles (5) are positioned and sunk, and leveled through multi-gasket flange connection, the lattice-type jacket (4) is hoisted and bolted, and the corner columns (6) are all installed with plumb bobs; after the lattice-type jacket is pressed, the adapter (3) is hoisted, and the adapter (3) is bolted to the corner columns (7); then the steel tower (2) is hoisted, and the lower part of the steel tower (2) is bolted to the adapter (3); finally, the fan (1) of the steel tower (2) is installed.

Claims

1. A prestressed hollow sandwich steel tube concrete lattice hybrid jacket, characterized by: The invention comprises a wind turbine (1), a steel tower (2), a switching device (3), a lattice-type jacket (4), steel piles (5) and prestressed tendons (11); the steel piles (5) are pre-positioned and sunk; the corner columns (6) in the lattice-type jacket (4) are connected to the steel piles (5), and the corner columns (6) are all installed with plumb bobs; the switching device (3) is connected to the lattice-type jacket (4); the lower end of the steel tower (2) is connected to the switching device (3); the corner columns (6) are prestressed hollow sandwich steel tube concrete, and 6 to 10 prestressed tendons are arranged in the sandwich concrete part, and the pre-tensioning method is adopted, and the pre-tensioned prestressed tendons (11) are arranged in the circumferential direction in the sandwich concrete of the corner columns (6) and arranged vertically along the length of the corner columns (6); the wind turbine (1) is arranged at the upper end of the steel tower (2); the centers of all the corner columns (6) are connected in sequence to form a square or a triangle; The diagonal rods (7) and corner columns (6) in the lattice-type jacket (4) are connected by welds. Holes are opened in the outer steel pipes (15) of the corner columns. The diagonal rods (7) extend into the interior of the corner columns and are connected to the inner steel pipes (14). Holes are opened at the ends of the diagonal rods (7). Prestressed tendons (11) pass through the holes. Concrete 3 to 5 times the diameter of the diagonal rods (7) is poured at the intersection nodes of the diagonal rods (7).

2. The prestressed hollow sandwich steel tube concrete lattice hybrid jacket according to claim 1, characterized in that: The steel pile (5) and the corner column (6) are connected by flange screws, and four stiffening ribs are evenly arranged along the circumference of the steel pile and the corner column. The screws are covered with multiple gaskets (10), and the gasket thickness is 0.1-2 mm. The length of the corner column (6) in the lattice-type jacket (4) is between 15 meters and 25 meters. The cross-sectional diameter of the corner column and the thickness of the steel pipe gradually decrease along the height, and the diameter change rate does not exceed 10%. The prestressed tendons (11) use prestressed steel strands and are tensioned before pouring concrete in the factory. The diagonal rods (7) in the lattice-type jacket (4) all use ordinary steel pipes. The transition device (3) uses a steel tube concrete composite shell, and bolts (18) are welded inside the steel plate, and then concrete is poured. A bracket (20) is set at the end of the steel tube concrete composite shell and is connected to the lower flange of the steel tower (2) through a screw.

3. The prestressed hollow sandwich steel tube concrete lattice hybrid jacket according to claim 2, characterized in that: The corner columns (6) in the lattice-type jacket (4) are provided with flanges at their ends, and four stiffening ribs are evenly arranged along the circumference, and are connected to the lower portion of the adapter (3) via screws. The adapter (3) is provided with four stiffening ribs at the screw connection.

4. The prestressed hollow sandwich steel tube concrete lattice hybrid jacket according to claim 3, characterized in that: The corner columns (6) in the lattice-type jacket (4) are uniformly arranged with hole ring partitions (13) at the upper and lower ends of the connection nodes, with the number of holes being 6 to 10, the prestressed tendons (11) passing through the holes, and 6 to 10 stiffening ribs are uniformly arranged along the circumference of the hole ring partition.

5. The prestressed hollow sandwich steel tube concrete lattice hybrid jacket according to claim 3, characterized in that: The lattice-type jacket frame (4), the adapter (3), the hole ring partition (13) and the gasket (10) are all completed in the factory; and the screw connection is all completed on site.

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