Construction method of a tidal power plant structure

Abstract

This invention relates to a construction method for a tidal power station structure, comprising the following steps: S1, installing and positioning the jacket structure using a floating crane; S2, floating the steel casing into the positioning hoist, drilling holes through the steel casing to the design elevation, and pouring pile foundations to form a steel-concrete composite pile structure; S3, prefabricating the foundation on land, pre-installing steel sleeves at the bottom of the foundation, and setting up a double-arm steel cofferdam around the upper perimeter of the foundation; S4, floating the prefabricated components to the design position, and connecting the steel sleeves with the top of the steel casing; S5, inflating airbags to form a sealed water-blocking system, and pumping out water from the double-arm steel cofferdam to create a dry working area; S6, cutting the portion of the top of the steel casing exceeding the pile foundation within the dry working area, and pouring the hollow structure of the foundation; S7, dismantling the double-arm steel cofferdam and jacket structure, and constructing the work platform; S8, hoisting the turbine assembly platform and the work platform as a whole. This invention optimizes the construction process of a tidal power station and improves the stability and durability of the structure.

Description

Technical Field

[0001] This invention belongs to the field of tidal energy power generation, and specifically relates to a construction method for a tidal energy power station structure. Background Technology

[0002] Tidal energy generation technology, as a cutting-edge new energy technology, has received widespread attention and research globally in recent years. In China, tidal energy generation technology has become one of the world's leading new energy technologies. The first few phases of the LHD marine tidal energy generation project (including Phase I, II, and III) adopted steel jacket structures as the generator assembly platform. This platform design has certain advantages in ensuring equipment installation and operation, and provides the necessary structural support and rigid foundation for the entire system.

[0003] However, current tidal power plants primarily utilize steel jacket structures for their main structures. While this offers advantages in initial construction, it faces challenges related to corrosion and durability during long-term operation, especially in marine environments where steel structures have shorter lifespans and higher maintenance costs. Furthermore, the turbine platforms of tidal power plants are typically located at depths of 30-40 meters, posing significant construction difficulties, particularly in the safe and efficient installation and securing of the structure in the seabed environment. Currently, there are no successful commercially viable examples of concrete-structured tidal power plants globally. Therefore, finding a simple, reliable, and highly efficient construction method for concrete-structured tidal power plants remains a critical technical challenge that the industry urgently needs to address. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a construction method for tidal power station structures, aiming to optimize the construction process of tidal power stations, improve the stability and durability of structures, and promote the sustainable development of tidal power generation projects.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] A construction method for a tidal current power station structure includes the following steps:

[0007] S1. After prefabrication of the jacket on land, the jacket is transported to the designed sea area, and the jacket is installed and positioned by a floating crane. The jacket is fixed with anchors and a positioning hoop is installed on the top of the jacket.

[0008] S2, the steel casing is floated into the positioning hoist, and after re-measuring the coordinates and verticality, the steel casing is driven into the seabed rock layer below the seabed stratum plane. The steel casing is drilled to the design elevation and the pile foundation is poured to form a steel-concrete composite pile structure.

[0009] S3, a prefabricated pier is constructed on land, a steel sleeve is pre-set at the bottom of the pier, and a double-armed steel cofferdam is set on the upper periphery of the pier. The double-armed steel cofferdam is connected to the pier through temporary connectors to form an integral prefabricated component.

[0010] S4, the prefabricated component is floated to the design position, the top of the steel sleeve is connected to the top of the steel casing, the steel casing passes through the steel sleeve, the prefabricated component is hoisted down to the design height, an airbag is preset between the steel sleeve and the steel casing, and the prefabricated component is fixed to the guide frame by a temporary connection device;

[0011] S5, the airbag is inflated to form a closed water-blocking system between the steel sleeve and the steel casing, and the water in the double-arm steel cofferdam is pumped out to form a dry operation area.

[0012] S6, cut the part of the top of the steel casing that extends beyond the pile foundation in the dry work area, and pour the hollow structure of the pile cap, with a column installed on top of the pile cap;

[0013] S7, dismantle the double-arm steel cofferdam and the guide frame;

[0014] S8, the turbine unit assembly platform, the work platform at the top of the column and other auxiliary structures are hoisted as a whole, and the installation is finally completed.

[0015] Preferably, in step S1, the anchor is an anchor pile or an anchor cable.

[0016] Preferably, in step S6, the column is formed by casting concrete in place using a formwork within the dry work area.

[0017] Preferably, in step S6, the column is prefabricated on land together with the pier and hoisted together with the double-arm steel cofferdam.

[0018] Preferably, in step S6, the prefabricated parts of the column and the foundation are both concrete structures or steel structures.

[0019] Preferably, in step S6, columns are respectively provided on both sides above the pier, and multiple detachable horizontal connecting systems are provided between the columns on both sides from top to bottom to increase the wave resistance between the columns.

[0020] Preferably, the double-arm steel cofferdam is circular and consists of inner and outer double-layer steel plates, with reinforcing ribs provided between the double-layer steel plates.

[0021] Preferably, in step S2, the top of the steel casing is flush with the top of the pile foundation, the lower end of the steel casing is embedded in the seabed rock layer to a depth less than the lower end of the pile foundation is embedded in the seabed rock layer, and the embedment depth of the steel casing in the rock layer is the most unfavorable position determined based on stress calculation.

[0022] Preferably, the platform has a circular, streamlined, or other planar shape that can reduce tidal energy loss.

[0023] Preferably, the airbag is an annular airbag.

[0024] Preferably, the annular airbag is connected to an automatic inflation system and equipped with a pressure sensor to automatically adjust the inflation level of the airbag according to real-time changes in ocean pressure.

[0025] Preferably, in step S5, a water pump system is used to pump out the water inside the double-arm steel cofferdam, and a water level monitoring sensor is used to detect the water level in the dry operation area in real time to ensure the formation of a stable dry operation area.

[0026] Preferably, the turbine unit includes a nacelle, blades, and a turbine jacket, wherein the turbine jacket is vertically fixed between the foundation and the working platform.

[0027] Preferably, the steel casing is coated with an anti-corrosion coating to improve its durability in marine environments.

[0028] Preferably, the pile foundation has a reinforcing steel mesh embedded in the concrete.

[0029] Compared with existing technologies, the advantages of this invention are as follows: This invention provides an innovative construction method for tidal power station structures. The tidal power station structure constructed using this method, through the combination of steel-concrete composite pile foundations and integral precast foundations, not only significantly improves the bending and shear bearing capacity of the overall tidal power station structure but also effectively extends its service life in marine environments. By employing a series of processes including onshore prefabrication, floating crane installation, on-site positioning, anchoring, drilling, and pouring, precise construction of complex underwater concrete structures under deep-water conditions (e.g., 30-40 meters and above) is achieved, significantly reducing the construction risks and difficulties associated with traditional underwater construction methods. Furthermore, by pre-setting airbags to form a closed water-blocking system during construction and utilizing double-arm steel cofferdams to construct a dry work area, the quality of concrete pouring and the stability of the construction environment are effectively guaranteed, thereby improving construction efficiency and safety. Simultaneously, this invention also provides a flexible construction method combining cast-in-place and prefabrication, which can be optimized according to actual engineering conditions, reducing construction costs. It has good promotion and demonstration significance and is of important technical value for promoting the industrialization of marine new energy engineering. Attached Figure Description

[0030] Figure 1 This is a construction schematic diagram of step S1 of the construction method for the tidal power station structure of the present invention;

[0031] Figure 2This is a construction schematic diagram of step S2 of the construction method for the tidal power station structure of the present invention;

[0032] Figure 3 This is a construction schematic diagram of step S3 in the construction method of the tidal power station structure of the present invention;

[0033] Figure 4 This is a construction schematic diagram of step S4 in the construction method of the tidal power station structure of the present invention;

[0034] Figure 5 This is a construction schematic diagram of step S5 in the construction method of the tidal power station structure of the present invention;

[0035] Figure 6 This is a construction schematic diagram of step S6 in the construction method of the tidal power station structure of the present invention;

[0036] Figure 7 This is a construction diagram illustrating steps S7-S8 of the construction method for the tidal power station structure of the present invention;

[0037] Figure 8 This is a schematic diagram of the double-arm steel cofferdam structure of the tidal power station structure of the present invention.

[0038] Explanation of reference numerals in the attached drawings: 1-jacket frame; 2-anchor; 3-positioning hoop; 4-steel casing; 5-pile foundation; 6-pillar; 7-steel sleeve; 8-double-arm steel cofferdam; 9-temporary connector; 10-airbag; 11-temporary connection device; 12-column; 13-working platform; 14-turbine unit; 15-lateral connection system. Detailed Implementation

[0039] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention belong to the present invention.

[0040] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0041] like Figure 1-7As shown in the figure, this embodiment discloses a construction method for a tidal power station structure, including the following steps:

[0042] S1, after the jacket 1 is prefabricated on land, it is transported to the designed sea area, the jacket 1 is installed and positioned by a floating crane, the jacket 1 is fixed by anchors 2, and positioning clamps 3 are installed on the top of the jacket 1;

[0043] In this step, high-quality component manufacturing is achieved in a controlled environment by prefabricating the jacket 1 on land. After being transported to the sea area, the jacket 1 is accurately positioned using a floating crane. Anchors 2 are used to firmly fix the jacket 1, while positioning clamps 3 provide a precise reference for subsequent operations. Anchors 2 can be anchor piles or anchor cables. Anchor piles provide high fixing force and are suitable for working conditions that require large tensile forces, while anchor cables are easy to install and adjust and can be flexibly selected according to the specific site conditions, thereby ensuring that the jacket 1 can be stably positioned in the sea area.

[0044] S2, the steel casing 4 is floated into the positioning hoist 3, and after re-measuring the coordinates and verticality, the steel casing 4 is driven into the seabed rock layer below the seabed stratum plane. The steel casing 4 is drilled to the design elevation and the pile foundation 5 is poured to form a steel-concrete composite pile structure.

[0045] In this step, the steel casing 4 is used as a construction guide and reinforcement component. Accurate positioning is ensured through re-measurement and adjustment. Concrete pouring of the pile foundation 5 is achieved by drilling holes inside the steel casing 4, thus forming a high-bearing-capacity steel-concrete composite pile structure. Furthermore, the top of the steel casing 4 is flush with the top of the pile foundation 5, and the embedment depth of the lower end of the steel casing 4 in the seabed rock stratum is less than the embedment depth of the lower end of the pile foundation 5 in the seabed rock stratum. This arrangement ensures continuous and stable force transfer between the steel casing 4 and the pile foundation 5, while allowing for deeper anchorage of the pile foundation 5, thereby improving the overall structural stability. The embedment depth of the steel casing 4 in the rock stratum is determined based on the most unfavorable position according to stress calculations. This depth parameter is obtained through detailed stress analysis, ensuring that the steel casing 4 can exert its optimal reinforcement effect under the most severe working conditions, thereby achieving the optimal stress performance of the entire steel-concrete composite pile structure.

[0046] S3, a precast pier 6 is constructed on land, a steel sleeve 7 is precast at the bottom of the pier 6, and a double-arm steel cofferdam 8 is set on the upper periphery of the pier 6. The double-arm steel cofferdam 8 is connected to the pier 6 through a temporary connector 9 to form an integral precast component.

[0047] In this step, the pier 6 is prefabricated on land as the key upper platform. The prefabricated components are formed by pre-setting steel sleeves 7 at its bottom and setting double-arm steel cofferdams 8 on the upper periphery, and then using temporary connectors 9, which facilitates rapid on-site installation.

[0048] S4, the floating crane lifts the prefabricated component to the design position, the top of the steel sleeve 7 and the steel casing 4 are connected, the steel casing 4 passes through the steel sleeve 7, the prefabricated component is lifted down to the design height, the air bladder 10 is between the steel sleeve 7 and the steel casing 4, and the prefabricated component and the guide frame 1 are fixed by the temporary connection device 11.

[0049] In this step, the prefabricated components are accurately hoisted to the design position by a floating crane to achieve precise docking of the steel sleeve 7 and the steel casing 4. The inner diameter of the steel sleeve 7 is slightly larger than the outer diameter of the steel casing 4 to reserve docking space. An airbag 10 is preset between the two as a buffer and water blocking device. At the same time, a temporary connection device 11 is used to ensure a stable connection between the overall components and the guide frame 1.

[0050] S5, the airbag 10 is inflated to form a closed water-blocking system between the steel sleeve 7 and the steel casing 4, and the water in the double-arm steel cofferdam 8 is pumped out to form a dry operation area.

[0051] In this step, the inflated airbag 10 forms a closed water-blocking system between the steel sleeve 7 and the steel casing 4, and establishes a dry working area by pumping out the water in the double-arm steel cofferdam 8, providing a good environment for subsequent construction; the airbag 10 is an annular airbag, and after the annular airbag 10 is inflated, it can form an annular continuous closed water-blocking system.

[0052] S6, cut the part of the top of the steel casing 4 that extends beyond the pile foundation 5 in the dry operation area, and pour the hollow structure of the pile cap 6. A column 12 is set on the top of the pile cap 6.

[0053] In this step, the portion of the steel casing 4 that extends beyond the pile foundation 5 is cut in the dry work area, and the hollow structure of the pile cap 6 is poured (the pouring part of the pile cap 6), so that the pile cap 6, the steel casing 4, and the pile foundation 5 are poured into an integrated structure. At the same time, a column 12 is set on top of the pile cap 6 to provide support.

[0054] In some embodiments, the column 12 is cast-in-place with concrete using formwork in a dry work area. This cast-in-place method, utilizing on-site formwork, ensures good bonding between the concrete and the surrounding environment, forming a continuous whole and improving structural resistance and sealing performance. In other embodiments, the column 12 is prefabricated on land along with the foundation 6 and hoisted together with the double-arm steel cofferdam 8. This prefabrication method ensures component quality under controlled conditions, and the overall hoisting not only shortens on-site construction time but also reduces the uncertainties and risks associated with on-site casting. Both the prefabricated parts of the column 12 and foundation 6 are either concrete or steel structures. Prefabricated concrete structures utilize the excellent compressive strength and durability of concrete, especially in marine environments where it exhibits good corrosion resistance and can operate stably for long periods. Quality can be well controlled during construction, costs are relatively low, and fire resistance is excellent. Prefabricated steel structures, on the other hand, have high tensile and bending strength, are lightweight, and are easy to precision machine and install quickly, achieving higher prefabrication accuracy. However, anti-corrosion treatment measures are required to ensure durability.

[0055] S7, dismantle the double-arm steel cofferdam 8, and dismantle the guide frame 1;

[0056] In this step, by dismantling the double-arm steel cofferdam 8 and the jacket scaffold 1, the auxiliary construction structure is cleared, providing sufficient space and safety conditions for the subsequent overall hoisting operation;

[0057] S8, hoist the turbine unit 14 assembly platform, the working platform 13 on top of the column 12 and other auxiliary structures as a whole, and finally complete the installation;

[0058] In this step, the turbine unit 14 assembly platform, the working platform 13 on top of the column 12, and other auxiliary structures are installed in one go by hoisting, ensuring precise connection between components and structural integrity, and finally realizing the assembly and installation of the entire tidal power station equipment.

[0059] Furthermore, columns 12 are respectively installed on both sides above the foundation 6, and multiple detachable transverse connecting systems 15 are installed between the columns 12 from top to bottom to increase the wave resistance between the columns 12. By setting multiple detachable transverse connecting systems 15, the load can be effectively distributed under the action of waves, enhancing the transverse stability of the entire structure, and facilitating maintenance or replacement when needed.

[0060] like Figure 8As shown, the double-arm steel cofferdam 8 is circular, composed of inner and outer double-layer steel plates, with reinforcing ribs between the double-layer steel plates. This design allows the double-arm steel cofferdam 8 to evenly distribute external loads. The structure of the inner and outer double-layer steel plates provides excellent rigidity, while the reinforcing ribs further enhance its overall stability and wave resistance. Furthermore, the pier 6 has a circular, streamlined, or other planar shape (top view) to reduce tidal energy loss. This design helps achieve uniform load distribution under ocean currents, reduces flow resistance, thereby improving energy capture efficiency. It also optimizes the stress state of the structure in dynamic water flow environments, reduces local stress concentration caused by wave impacts, and extends the overall service life.

[0061] Furthermore, the annular airbag is connected to an automatic inflation system and equipped with a pressure sensor, which automatically adjusts the inflation level of the airbag according to real-time changes in ocean pressure. This design ensures that the airbag can automatically adjust the inflation amount under various sea conditions, maintain the stability of the sealed water-blocking system, effectively prevent seawater infiltration, and ensure the stability of the construction area environment.

[0062] In addition, in step S5, the water in the double-arm steel cofferdam 8 is pumped out using a water pump system, and the water level in the dry work area is monitored in real time by a water level monitoring sensor to ensure the formation of a stable dry work area. This measure ensures that the construction area is dry by continuously monitoring water level changes, providing a reliable environment for subsequent concrete pouring and structural installation.

[0063] The turbine unit 14 includes a nacelle, blades, and a turbine jacket. The turbine jacket is vertically fixed between the foundation 6 and the working platform 13. This arrangement ensures a stable mechanical connection between the various parts of the turbine unit, effectively capturing ocean current energy while guaranteeing installation accuracy and operational stability. The steel casing 4 is coated with an anti-corrosion coating to improve durability in the marine environment. The anti-corrosion coating effectively prevents seawater and salt from corroding the steel, extending the service life of the components and reducing later maintenance costs. The pile foundation 5 incorporates reinforcing steel mesh within the concrete. The reinforcing steel mesh improves the compressive and crack resistance of the concrete, enhancing the overall structural stability and load-bearing capacity of the pile foundation.

[0064] In summary, this invention discloses a construction method for a tidal power station structure. This method achieves efficient and precise installation of the tidal power station structure in the sea by prefabricating key components such as the jacket frame 1, steel casing 4, foundation 6, columns 11, and working platform 13 on land, and employing a series of steps including floating crane operation, anchoring, positioning, drilling and casting, and hoisting of the prefabricated components. This construction method not only simplifies the complex underwater operation process and ensures a good connection between the concrete and steel structures, but also significantly improves the structure's bending and shear bearing capacity and wave resistance. Furthermore, it can construct a closed water-blocking system even in deep water environments, ensuring the safety and reliability of the project construction. Therefore, this technical solution greatly shortens the construction period, reduces construction risks and costs, and has important demonstrative and promotional significance for improving the construction quality of tidal power stations and promoting the industrialization of marine new energy projects.

[0065] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Under the concept of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of the present invention as described above. For the sake of brevity, they are not provided in detail. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A construction method for a tidal current power station structure, characterized in that, Includes the following steps: S1, after the prefabrication of the jacket (1) on land, it is transported to the design sea area, and the jacket (1) is installed and positioned by a floating crane. The jacket (1) is fixed by anchors (2), and a positioning hoop (3) is installed on the top of the jacket (1). S2, the steel casing (4) is floated into the positioning hoop (3), and after re-measuring the coordinates and verticality, the steel casing (4) is driven into the seabed rock layer below the seabed stratum plane. The steel casing (4) is drilled to the design elevation and the pile foundation (5) is poured to form a steel-concrete composite pile structure. S3, a prefabricated pier (6) is constructed on land, a steel sleeve (7) is prefabricated at the bottom of the pier (6), and a double-arm steel cofferdam (8) is set on the upper periphery of the pier (6). The double-arm steel cofferdam (8) is connected to the pier (6) through a temporary connector (9) to form an integral prefabricated component. S4, the prefabricated component is floated to the design position, the top of the steel sleeve (7) is connected to the top of the steel casing (4), the steel casing (4) passes through the steel sleeve (7), the prefabricated component is hoisted down to the design height, an airbag (10) is preset between the steel sleeve (7) and the steel casing (4), and the prefabricated component is fixed to the guide frame (1) by a temporary connection device (11); S5, the airbag (10) is inflated to form a closed water-blocking system between the steel sleeve (7) and the steel casing (4), and the water in the double-arm steel cofferdam (8) is pumped out to form a dry operation area; S6, cut the part of the top of the steel casing (4) that extends beyond the pile foundation (5) in the dry operation area, and pour the hollow structure of the pile cap (6), and set up a column (12) on the top of the pile cap (6). S7, dismantle the double-arm steel cofferdam (8) and dismantle the jacket (1). S8, hoist the turbine unit (14) assembly platform, the construction work platform (13) on top of the column (12) and other auxiliary structures, and finally complete the installation.

2. The construction method for the tidal power station structure according to claim 1, characterized in that, In step S1, the anchor (2) is an anchor pile or an anchor cable.

3. The construction method for the tidal power station structure according to claim 1, characterized in that, In step S6, the column (12) is formed by casting concrete in the dry work area using a template.

4. The construction method for the tidal power station structure according to claim 1, characterized in that, In step S6, the column (12) is prefabricated on land together with the pier (6) and hoisted together with the double-arm steel cofferdam (8).

5. The construction method for the tidal power station structure according to claim 4, characterized in that, In step S6, the prefabricated parts of the column (12) and the pier (6) are both concrete structures or steel structures.

6. The construction method for the tidal power station structure according to claim 1, characterized in that, In step S6, columns (12) are respectively provided on both sides above the platform (6), and multiple detachable horizontal connecting systems (15) are provided between the columns (12) on both sides from top to bottom to increase the wave resistance between the columns (12).

7. The construction method for the tidal power station structure according to claim 1, characterized in that, The double-arm steel cofferdam (8) is circular and is composed of inner and outer double-layer steel plates with reinforcing ribs between the double-layer steel plates.

8. The construction method for the tidal power station structure according to claim 1, characterized in that, In step S2, the top of the steel casing (4) is flush with the top of the pile foundation (5), the lower end of the steel casing (4) is embedded in the seabed rock layer at a depth less than the lower end of the pile foundation (5) is embedded in the seabed rock layer, and the depth of the steel casing (4) embedded in the rock layer is the most unfavorable position determined according to the stress calculation.

9. The construction method for the tidal power station structure according to claim 1, characterized in that, The platform (6) is circular or streamlined to reduce tidal energy loss.

10. The construction method for the tidal power station structure according to claim 1, characterized in that, The airbag is a ring-shaped airbag.

11. The construction method for the tidal power station structure according to claim 10, characterized in that, The annular airbag is connected to an automatic inflation system and is equipped with a pressure sensor that automatically adjusts the inflation level of the airbag according to real-time changes in ocean pressure.

12. The construction method for the tidal power station structure according to claim 1, characterized in that, In step S5, the water body inside the double-arm steel cofferdam (8) is pumped out using a water pump system, and the water level in the dry operation area is detected in real time by a water level monitoring sensor to ensure the formation of a stable dry operation area.

13. The construction method for the tidal power station structure according to claim 1, characterized in that, The turbine unit (14) includes a nacelle, blades and a turbine jacket, which is vertically fixed between the pier (6) and the working platform (13).

14. The construction method for the tidal power station structure according to claim 1, characterized in that, The steel casing (4) is coated with an anti-corrosion coating to improve its durability in marine environments.

15. The construction method for the tidal power station structure according to claim 1, characterized in that, The pile foundation (5) has a reinforcing steel mesh set in the concrete.

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