Process planning method

Abstract

To provide a process planning method capable of shortening the process of a construction project.SOLUTION: A process planning method for planning a process of a construction project of a monopile base, the process planning method comprising a structural analysis process SA3 in which a computer performs structural analysis of a model of the monopile base a plurality of times, and a first manufacturing process SA3 that is started after completion of seismic response analysis included in a first structural analysis process SA3 and before completion of seismic response analysis included in a second structural analysis process SB1, the first manufacturing process SB1 not manufacturing an interface flange of a transition piece, A portion of the transition piece other than the interface flange is manufactured, and in the first manufacturing step SB1, a connecting portion of the monopile main body to be connected to the transition piece in an overlapping manner when viewed horizontally is manufactured, and a portion of the monopile main body other than the connecting portion is not manufactured.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a process planning method. [Background technology]

[0002] Conventionally, structures are manufactured in a factory and then assembled and installed at a construction site. Patent document 1 discloses a method for constructing vertical structures in which a unit structure, prefabricated in a factory, consists of a single flat metal plate with horizontal reinforcing ribs welded to its outer surface. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 62-86273 Summary of the Invention [Problem to be solved by the invention]

[0004] The conventional construction method has a problem in shortening the construction project schedule.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and aims to provide a process planning method that can shorten the process of a construction project. [Means for solving the problem]

[0006] A process planning method according to one embodiment of the present disclosure is a process planning method for planning the process of a construction project for a monopile foundation having a monopile body and a transition piece and supporting the tower of an offshore wind turbine, the process comprising: a structural analysis process in which a computer performs a structural analysis of a model of the monopile foundation multiple times; and a first fabrication process in which at least some of the components constituting the monopile foundation are fabricated after completion of an earthquake response analysis included in a first structural analysis process and before completion of an earthquake response analysis included in a second structural analysis process, wherein the first fabrication process fabricates the transition piece, does not fabricate an interface flange of the transition piece, and fabricates a portion of the transition piece other than the interface flange; the first fabrication process fabricates the monopile body, and the first fabrication process fabricates a connection portion of the monopile body that is connected to the transition piece in a state that overlaps with the transition piece in a horizontal view, and does not fabricate a portion of the monopile body other than the connection portion. [Effects of the Invention]

[0007] According to the present disclosure, a process planning method that can shorten the process of a construction project can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing a first example of an offshore structure according to an embodiment. [Figure 2] FIG. 2 is a diagram showing a state in which a plurality of the marine structures shown in FIG. 1 are installed. [Figure 3] FIG. 2 is a cross-sectional view of the monopile body taken along the III-III direction shown in FIG. 1. [Figure 4] FIG. 2 is an enlarged view of part IV shown in FIG. [Figure 5] 1 is a flow chart of a process planning method according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an offshore structure and a process planning method for an offshore structure according to an embodiment of the present disclosure will be described with reference to the drawings. The marine structure according to this embodiment is a foundation structure that supports the tower of an offshore wind turbine. The marine structure may be, for example, a jacket foundation, a monopile foundation, or any other structure.

[0010] (Regarding offshore structures) FIG. 1 is a diagram showing a first example of a marine structure 1 according to an embodiment. FIG. 2 is a diagram showing a state in which a plurality of marine structures 1 shown in FIG. 1 are installed. As shown in Fig. 1, in this embodiment, the offshore structure 1 is a monopile foundation. As shown in Fig. 2, a plurality of offshore structures 1 may exist in the same wind farm or sea area (hereinafter referred to as installation location A), for example.

[0011] In this embodiment, the marine structure 1, which is a monopile foundation, has a monopile body 10, a transition piece 20, and ancillary equipment 30, as shown in FIG. The monopile body 10 is a cylindrical member that is driven into the seabed OF. In this embodiment, the monopile body 10 refers to, for example, a steel pipe at least a portion of which is embedded in the ground. In this embodiment, at least one of the inner and outer surfaces of the monopile body 10 may be coated with corrosion protection. In this embodiment, the monopile body 10 is formed by connecting a plurality of unit cylindrical bodies 11, which are cylindrical members of any length, in the longitudinal direction, as shown in Fig. 1. The monopile body 10 may be made of steel or any other material. Furthermore, in this embodiment, the multiple marine structures 1 installed at the same installation location A as described above may have some or all of the shape of the monopile body 10 in common, or the shape may be set individually as appropriate to suit the conditions such as the ground and water depth at each installation location of the multiple marine structures 1.

[0012] FIG. 3 is a cross-sectional view of the monopile body 10 taken along the line III-III in FIG. In this embodiment, the monopile body 10 may be formed so that its cross section has a circular shape, as shown in Fig. 3. A cylindrical unit 11 having such a cross section may be formed, for example, by connecting the ends of a plurality of curved plates 11A as shown in Fig. 3, by bending a steel plate, or by integrally molding a cylindrical member. Alternatively, the monopile body 10 may be formed to have an elliptical cross-sectional shape or any other cross-sectional shape.

[0013] As described above, the monopile body 10 is formed by connecting a plurality of unit tubular bodies 11 in the longitudinal direction. At this time, the portion of the monopile body 10 that is installed underground, and in particular the portion close to the surface (seabed surface) of the seabed OF, may be subjected to a relatively large bending moment compared to other portions. For this reason, the unit tubular bodies 11 located in these portions may have a greater plate thickness than the unit tubular bodies 11 located in other portions.

[0014] FIG. 4 is an enlarged view of part IV shown in FIG. As shown in Fig. 4, a cable C may be provided inside the monopile body 10. The cable C is, for example, a cable for connecting various devices (not shown) provided inside the offshore wind turbine WM with a submarine cable (not shown) laid on the seabed OF. To enable connection between the submarine cable (not shown) and the cable C shown in Fig. 4, a hole (not shown) may be provided in the side wall of the monopile body 10 near the seabed. Note that if the cable C and the submarine cable (not shown) are connected by a joint (not shown), the boundary between the cable C and the submarine cable (not shown) may be identified by the location of the joint (not shown). Alternatively, the boundary between the cable C and the submarine cable (not shown) may be identified by considering the part that has landed on the seabed as the submarine cable (not shown).

[0015] As shown in Figures 1 and 4, the transition piece 20 is disposed on the upper part of the monopile body 10. Specifically, the transition piece 20 is provided so as to overlap a portion of the monopile body 10 including its upper end when viewed in the horizontal direction. That is, the upper part of the monopile body 10 is inserted into the transition piece 20 from below. As shown in Figure 4, the portion of the monopile body 10 including its upper end and the transition piece 20 are preferably cone-shaped. That is, the portion of the monopile body 10 including its upper end and the transition piece 20 are preferably truncated cones whose diameter decreases from bottom to top. As shown in Fig. 4, a portion of the monopile body 10 including its upper end and the transition piece 20 may be arranged so as to overlap each other when viewed horizontally, and may be fixed by grout G. The grout G is injected into the gap (annular space) between the upper part of the monopile body 10 and the transition piece 20. The transition piece 20 may be made of, for example, steel, or any other material. The transition piece 20, which is placed on top of the monopile body 10 as described above, connects the monopile body 10 to the tower T of the offshore wind turbine WM. The tower T extends upward from the connection position with the transition piece 20. The offshore wind turbine WM is installed offshore. In this embodiment, the transition piece 20 has an interface flange IF, as shown in Fig. 4. The interface flange IF is provided at the upper end of the transition piece 20. In this embodiment, a similar interface flange IF is also provided at the lower end of the tower T of the offshore wind turbine WM. The connection between the transition piece 20 and the tower T of the offshore wind turbine WM is achieved by joining the interface flanges IF provided on the transition piece 20 and the tower T of the offshore wind turbine WM with bolts B, as shown in Fig. 4. The transition piece 20 may have a function to adjust the connection angle with the tower T. With this configuration, the tower T of the offshore wind turbine WM can be adjusted to extend vertically when connected to the lower end of the tower T of the offshore wind turbine WM. As shown in Fig. 4, a cable C may be provided inside the transition piece 20. A hole H having a circular, elliptical, or any other shape may be provided inside the transition piece 20 to pass the cable C through. As mentioned above, a plurality of marine structures 1 may be present at the same installation location A, as shown in Fig. 2. In this case, it is preferable that the shape of the hole H provided inside the transition piece 20 be the same for the plurality of marine structures 1. In this embodiment, the transition pieces 20 may have a common structure or may be different in the multiple marine structures 1 installed at the same installation site A as described above.

[0016] The auxiliary facilities 30 are provided to enable workers to move around and perform various tasks on the marine structure 1. In this embodiment, the auxiliary facilities 30 include, for example, a mooring facility 31, a ladder 32, a landing 33, a work platform 34, and a walkway 35, as shown in Fig. 4. Each of the auxiliary facilities 30 may be made of, for example, steel, or any other material. In this embodiment, the auxiliary equipment 30 may have a common structure among the multiple marine structures 1 installed at the same installation site A as described above, or may have different structures.

[0017] The mooring equipment 31 is a member of the marine structure 1 for mooring a work boat. In this embodiment, the mooring equipment 31 shown in Fig. 4 has, for example, a pair of rod-shaped members extending in the vertical direction. Workers move from the work boat to the marine structure 1 with the work boat moored to this mooring equipment 31. The ladder 32 is used for workers to move up and down after moving to the marine structure 1. In this embodiment, the ladder 32 shown in Fig. 4 is provided, for example, between a pair of rod-shaped members of the mooring equipment 31. As shown in Fig. 4, the landing 33 is provided at the upper end of the ladder 32. In this embodiment, the landing 33 is a place where a worker who moves from the work boat to the marine structure 1 and moves upward using the ladder 32 gets off. The work platform 34 is a place where workers can perform various tasks. The work platform 34 may be provided with a davit crane DC for lifting materials, as shown in Fig. 4, for example. The passage 35 is a section where workers move. In this embodiment, the passage 35 includes the ladder 32 and the landing 33. In other words, in this embodiment, the ladder 32 and the landing 33 may be collectively referred to as the passage 35. The marine structure 1 according to this embodiment is configured by the above components.

[0018] (About process planning methods) Next, a process planning method according to this embodiment will be described. The process planning method according to this embodiment is a method for planning the process of a construction project for an offshore structure 1 that supports the tower T of an offshore wind turbine WM. The process planning method described below is applied to the manufacture of the offshore structure 1 according to this embodiment. The offshore structure 1 according to this embodiment is manufactured through a process based on the process planning method and installed offshore. In this embodiment, manufacturing the marine structure 1 includes procuring materials, processing the materials to form various components, and assembling the various components to form the marine structure 1.

[0019] FIG. 5 is a flow chart of a process planning method according to an embodiment. As shown in FIG. 5, the process planning method according to this embodiment includes a design review flow SA and a production flow SB. The design review flow SA is a flow for reviewing the shape of the marine structure 1. As shown in Fig. 5, the design review flow SA includes a preliminary investigation step SA1, a shape review step SA2, and a structural analysis step SA3.

[0020] The preliminary survey process SA1 is a process of investigating the specific conditions, such as ground conditions and wave conditions, at the installation site A where the marine structure 1 and offshore wind turbine WM will be installed. Specifically, in the preliminary survey process SA1, for example, wind observation, geological survey, bathymetric survey, indoor soil testing, etc. are carried out. The results of the various surveys in the preliminary survey process SA1 are reflected in the analysis conditions in, for example, the shape consideration process SA2 and the structural analysis process SA3. Before or after the preliminary inspection process SA1, a first pre-production process SB1a (described later) in the production flow SB may be started.

[0021] The shape examination process SA2 is a process of examining the shape of the offshore structure 1 and creating a model of the offshore structure 1. Specifically, for example, in the offshore structure 1 which is a monopile foundation, the diameter and thickness of the monopile body 10, the diameter and thickness of the transition piece 20, etc. are examined and a model to be used in the structural analysis process SA3 is created.

[0022] In this embodiment, in the first pre-fabrication process SB1a (described later), highly versatile materials from among those constituting the monopile body 10 and the transition piece 20 may be secured in advance as inventory. That is, for example, multiple types of steel pipes with different diameters, thicknesses, and materials may be procured in advance as materials constituting the monopile body 10 and the transition piece 20. In such cases, the diameters and thicknesses of the multiple types of steel pipes vary in predetermined numerical increments. The predetermined numerical values ​​may be, for example, any arbitrary values ​​as appropriate. The predetermined numerical values ​​may also be, for example, discrete values. In this embodiment, multiple shapes of the offshore structure 1 may be considered in the shape consideration step SA2. In the shape consideration step SA2, the diameters and thicknesses of the monopile body 10 and the transition pieces 20 are preferably set in predetermined numerical increments to match the steel pipes secured in stock. Furthermore, the predetermined numerical values ​​are preferably discrete values ​​to match the steel pipes secured in stock. This makes it easier to perform the structural analysis step SA3, which will be described next, for example. Furthermore, it makes it easier to prevent excess inventory when procuring materials for the monopile body 10 and the transition pieces 20 (details will be described later). After the shape of the marine structure 1 is considered in the shape consideration process SA2, the first intermediate manufacturing process SB1b (described later) in the manufacturing flow SB is started, and the process moves to the structural analysis process SA3. However, starting the first intermediate manufacturing process SB1b is not essential. In other words, whether or not to start the first intermediate manufacturing process SB1b is determined as appropriate.

[0023] The structural analysis step SA3 is a step of performing a structural analysis of the model of the marine structure 1. In this embodiment, the structural analysis step SA3 may be performed multiple times. In other words, in this embodiment, the structural analysis step SA3 may be a step in which a computer performs a structural analysis of the model of the marine structure 1 multiple times. The structural analysis process SA3 is performed based on the shape of the marine structure 1 considered in the shape consideration process SA2. As shown in Fig. 5, the structural analysis process SA3 includes an analysis implementation step SA3a, a first confirmation step SA3b, a second confirmation step SA3c, a third confirmation step SA3d, and a review step SA3e.

[0024] The analysis execution step SA3a is a step of performing a structural analysis of the model of the marine structure 1. In this embodiment, the analysis execution step SA3a performs, for example, eigenvalue analysis, wind-wave integrated analysis, earthquake response analysis, etc. The eigenvalue analysis, wind-wave integrated analysis, and earthquake response analysis may be performed by frame structure analysis or finite element analysis. It is also preferable that the wind-wave integrated analysis and earthquake response analysis be performed by time history response analysis. Furthermore, in the analysis execution step SA3a, a static analysis may be performed on the auxiliary equipment 30. In the static analysis, loads such as wave loads, ship docking loads, and towing loads may be considered. If a plurality of shapes of the marine structure 1 are considered in the shape consideration step SA2, for example, analysis is performed for each shape in the analysis execution step SA3a.

[0025] The first confirmation step SA3b is a step for confirming the results of the analysis performed in the analysis performing step SA3a. Specifically, the first confirmation step SA3b confirms whether or not all components of the marine structure 1 can be finalized based on the overall shape of the model of the marine structure 1 when the analysis performing step SA3a is performed. If it is determined that all components of the marine structure 1 can be finalized based on the overall shape of the model of the marine structure 1 (SA3b: possible), the structural analysis step SA3 is terminated and the shape of the marine structure 1 is finalized. If it is determined that all components of the marine structure 1 cannot be finalized (SA3b: not possible), the process proceeds to the second confirmation step SA3c.

[0026] The second confirmation step SA3c is a step of confirming whether or not the shape of a part of the model of the marine structure 1, for which it has been determined that not all components can be finalized, can be finalized. Note that the part of the model of the marine structure 1 refers to either the monopile main body 10 or the transition piece 20 of the marine structure 1. In this case, the part of the model of the marine structure 1 may be a part of the monopile main body 10 or a part of the transition piece 20. Of the parts of the model of the marine structure 1, those parts that are determined to be finalizable (SA3c: possible parts) start the first manufacturing process SB1c (described later) in the manufacturing flow SB. Of the parts of the model of the marine structure 1, those parts that are determined not to be finalizable (SA3c: not possible parts) proceed to the third confirmation step SA3d.

[0027] The third confirmation step SA3d is a step of confirming the degree of reinforcement required for the members that are determined not to be finalizable among the parts of the model of the marine structure 1. In other words, the third confirmation step SA3d is a step of confirming the degree to which the shape of the model of the marine structure 1 needs to be changed. If it is determined that a relatively large-scale modification of the shape is required for a component that is determined not to be finalizable (SA3d: another shape review process is required), the component moves to the shape review process SA2, where the shape is reconsidered.If it is determined that a large-scale modification of the shape is not required for a component that is determined not to be finalizable (SA3d: only a review of the component cross section and material is sufficient), the component moves to the review step SA3e.

[0028] The review step SA3e is a step in which, when it is determined that no large-scale shape modification is necessary for a component that has been determined not to be finalizable, the shape of the model of the component in the marine structure 1 is reviewed. In the review step SA3e, for example, the cross-sectional shape of the model of the component and the material used are reviewed. For components for which the review step SA3e has been completed, the analysis execution step SA3a is performed again. In this embodiment, the shape examination step SA2 and the structure analysis step SA3 may be repeated until the shape of the marine structure 1 is finally determined.

[0029] In this embodiment, for example, if multiple types of steel pipes with diameters varying in predetermined numerical increments are kept in stock as materials for constructing the monopile body 10 and the transition piece 20, the structural analysis step SA3 may only perform structural analysis of the model of the offshore structure 1 at the predetermined diameter increments. In this case, it is preferable that in the shape consideration step SA2, models with the predetermined diameter increments are considered as multiple shapes to match the multiple types of steel pipes kept in stock. In other words, in the structural analysis step SA3, the diameters of the monopile body 10 and the transition piece 20 may be set at the predetermined numerical increments in the shape consideration step SA2 described above to match the multiple types of steel pipes kept in stock. Specifically, for example, the predetermined diameters are preferably in 500-mm increments within a range from 7,000 mm to 15,000 mm in diameter, but may be any other numerical value.

[0030] Furthermore, for example, if multiple types of plate materials or steel pipes with thicknesses varying in predetermined increments are stocked as materials for constructing the monopile body 10 or the transition piece 20, the structural analysis step SA3 may only perform structural analysis of the model of the offshore structure 1 at the predetermined plate thickness increments. In this case, it is preferable that in the shape consideration step SA2, models with the predetermined plate thickness increments are considered as multiple shapes in accordance with the multiple types of plate materials and steel pipes stocked. In other words, in the structural analysis step SA3, the plate thicknesses of the monopile body 10 or the transition piece 20 may be set at the predetermined numerical increments in the shape consideration step SA2 described above in accordance with the multiple types of plate materials and steel pipes stocked. Specifically, for example, the predetermined plate thickness is preferably in 5-mm increments in the range from 70 mm to 100 mm, but may be any other value.

[0031] As described above, by setting the diameter and thickness in the structural analysis step SA3 in predetermined numerical increments to match the multiple types of plate materials and steel pipes kept in stock, it is possible to prevent excess inventory and also to reduce the number of analyses to be performed at one time in the structural analysis step SA3, thereby making it easier to perform the structural analysis step SA3. In this manner, the design review flow SA is performed.

[0032] Here, in the structural analysis step SA3, the various analyses described above may take several months. Furthermore, the shape of the offshore structure 1 (e.g., component cross sections, materials, etc.) is often roughly determined at the time of the first structural analysis step SA3. In this case, if the structural analysis step SA3 is performed several times and the fabrication of the offshore structure 1 begins after the shape of the offshore structure 1 is finally determined, there is room to shorten the construction project process for the offshore structure 1. Therefore, in this embodiment, the manufacturing flow SB is carried out as follows, which contributes to shortening the construction project process.

[0033] The fabrication flow SB is a flow for fabricating the marine structure 1. Specifically, the fabrication flow SB is a flow for procuring materials that constitute the marine structure 1 and processing the procured materials. As shown in FIG. 5, the fabrication flow SB includes a first fabrication process SB1, a second fabrication process SB2, and an assembly process SB3.

[0034] The first fabrication process SB1 is, for example, the structural analysis process SA3 described above, a process that is started after the completion of the earthquake response analysis included in the first structural analysis process SA3 and before the completion of the earthquake response analysis included in the second structural analysis process SA3. The first fabrication process SB1 is a process of fabricating at least some of the members that make up the marine structure 1. Since the analysis results of each component influence each other, production (procurement) would normally begin after all of the above-mentioned structural analysis process SA3 has been completed. However, in this embodiment, the first production process SB1 contributes to accelerating the completion of the marine structure 1 by, for example, starting production of components that are deemed to be finalizable in the above-mentioned structural analysis process SA3 in advance. In this embodiment, the first fabrication process SB1 may fabricate, for example, some of the components that make up the marine structure 1. Examples of the parts fabricated in the first fabrication process SB1 will be described later. Alternatively, all of the components that make up the marine structure 1 may be fabricated in the first fabrication process SB1.

[0035] In this embodiment, the first manufacturing process SB1 includes a front first manufacturing process SB1a, a middle first manufacturing process SB1b, and a rear first manufacturing process SB1c. Note that in this embodiment, the first manufacturing process SB1 may include only one or two of these processes. Also, in this embodiment, performing the first manufacturing process SB1 means performing at least one of these processes.

[0036] The pre-first manufacturing process SB1a is a process in the first manufacturing process SB1 that is started before or after the preliminary survey process SA1. The pre-first manufacturing process SB1a is a process of securing highly versatile materials from among those that make up the monopile body 10 and the transition pieces 20 as inventory in advance. In the pre-first manufacturing process SB1a, for example, an order is placed for multiple types of steel pipes with different diameters, thicknesses, and materials as materials that make up the monopile body 10 and the transition pieces 20. In this case, the diameters and thicknesses of the multiple types of steel pipes may be varied in increments of a predetermined value. The predetermined value may be, for example, an arbitrary value that is appropriately determined. The predetermined value may also be, for example, a discrete value.

[0037] The first intermediate manufacturing process SB1b is a process of the first manufacturing process SB1 that is started before the start of the structural analysis process SA3. In this embodiment, the first intermediate manufacturing process SB1b is started after the shape of the marine structure 1 has been considered in the shape consideration process SA2. In the first intermediate manufacturing process SB1b, for example, materials that were not procured in the first preceding manufacturing process SB1a are procured. Specifically, in the first intermediate manufacturing process SB1b, for example, ordering is performed for materials that constitute the monopile body 10 or the transition piece 20, the shapes of which have been finalized in the shape review process SA2.

[0038] As described above, in the shape examination step SA2 and the structural analysis step SA3, the diameters and thicknesses of the monopile body 10 and the transition pieces 20 of the offshore structure 1 are set in predetermined numerical increments to match the plates and steel pipes procured in the first fabrication step SB1a. This makes it possible to start processing the components using appropriate materials as soon as the diameters and thicknesses of the monopile body 10 and the transition pieces 20 are determined as the structural analysis step SA3 progresses.

[0039] Furthermore, by setting the diameters and thicknesses of the monopile body 10 and the transition pieces 20 as described above, it is possible to reduce the number of types of materials that need to be prepared in the first front manufacturing process SB1a and the first middle manufacturing process SB1b, which makes it easier to prevent excess inventory from occurring. It is preferable that, among the materials having a plurality of diameters and thicknesses procured as described above, those not used for the monopile body 10 or the transition piece 20 are diverted to other members, structures, etc. This also makes it possible to more reliably prevent excess inventory from occurring. In the first intermediate fabrication process SB1b, materials to be used for the auxiliary equipment 30 of the marine structure 1 may be procured. However, the materials to be used for the auxiliary equipment 30 of the marine structure 1 may be procured in the first front fabrication process SB1a or the first rear fabrication process SB1c. The first intermediate manufacturing process SB1b can contribute to the early completion of the marine structure 1 by procuring materials in advance as described above.

[0040] The post-first fabrication process SB1c is a process in the first fabrication process SB1 that is started after the start of the structural analysis process SA3. In this embodiment, the post-first fabrication process SB1c fabricates, for example, a component (SA3c: possible component) that is determined to be finalizable from among a portion of the model of the offshore structure 1 in the second confirmation step SA3c of the structural analysis process SA3. As described above, the portion of the model of the offshore structure 1 in the second confirmation step SA3c refers to either the monopile main body 10 or the transition piece 20 of the offshore structure 1. In the post-first fabrication process SB1c, it is preferable to fabricate one of these that is determined to be finalizable and for which fabrication can be started.

[0041] In the post-first fabrication process SB1c, materials are mainly processed to form various components of the marine structure 1. In this embodiment, the start time of the post-first fabrication process SB1c is preferably set appropriately depending on, for example, the design difficulty of each component, the fabrication process, the offshore construction process, etc. Alternatively, the post-first fabrication process SB1c may be started as soon as the shapes of each component are determined as the structural analysis process SA3 progresses.

[0042] In this embodiment, performing the first manufacturing process SB1 described above contributes to the early completion of the offshore wind turbine WM. Note that it is preferable that the members to be manufactured in the first manufacturing process SB1 are determined appropriately after careful consideration. In this embodiment, the first fabrication process SB1 fabricates, for example, components that are rate-limiting in the fabrication process of the marine structure 1. In this embodiment, being rate-limiting means that there is room to shorten the fabrication process of the marine structure 1, for example, because it takes a long time to procure materials or a long time to process and assemble materials. Below, we will explain several examples of members that are rate-limiting in the process of manufacturing the marine structure 1. In this embodiment, it is preferable to appropriately select any of the members described below and manufacture them in the first manufacturing process SB1.

[0043] In the first manufacturing process SB1, for example, a member with a shear key is manufactured. Since a shear key requires a relatively large amount of welding, it takes a long time to manufacture. For this reason, a member with a shear key may be manufactured in the first manufacturing process SB1.

[0044] In the first manufacturing process SB1, for example, auxiliary equipment 30 may be manufactured. The auxiliary equipment 30 is at least one of mooring equipment 31, ladder 32, landing 33, working platform 34, and walkway 35. These auxiliary equipment 30 require a relatively large amount of welding, and therefore require a long period of time to manufacture. For this reason, these auxiliary equipment 30 may be manufactured in the first manufacturing process SB1.

[0045] In the first manufacturing process SB1, for example, the interface flange IF may be manufactured. The interface flange IF requires time and effort for corrosion prevention processing, and therefore takes a long time to manufacture. For this reason, the interface flange IF may be manufactured in the first manufacturing process SB1.

[0046] In the first manufacturing process SB1, for example, the monopile body 10 may be manufactured. As described above, the monopile body 10 is formed by connecting a plurality of unit cylindrical bodies 11 in the longitudinal direction, and therefore a relatively large amount of welding is required. Also, in the first manufacturing process SB1, at least one of the inner and outer surfaces of the monopile body 10 may be coated with anti-corrosion coating. For this reason, manufacturing the monopile body 10 takes a long time. For this reason, the monopile body 10 may be manufactured in the first manufacturing process SB1.

[0047] Furthermore, in the first fabrication process SB1, for example, the portion of the monopile body 10 that will be installed underground may be fabricated. As described above, the portion of the monopile body 10 that will be installed underground, and in particular the portion close to the surface (seabed surface) of the seabed OF, may be subjected to a relatively large bending moment compared to other portions, and therefore a material with a relatively large plate thickness may be used. Such materials require a large amount of welding compared to materials with normal plate thicknesses, and therefore may require a long period of time to process. For this reason, in the first fabrication process SB1, the portion of the monopile body 10 that will be installed underground may be fabricated. More specifically, for example, materials to be used for the portion of the monopile body 10 that will be installed underground may be procured in advance. In addition, in the first manufacturing process SB1, a connection portion of the monopile body 10 is manufactured that is connected to the transition piece 20 in a state that overlaps it when viewed horizontally, and no portion of the monopile body 10 other than the connection portion is manufactured.

[0048] In this embodiment, in the first manufacturing process SB1, in addition to the rate-limiting components described above, components whose shapes are unlikely to change before and after the structural analysis process SA3 may also be manufactured. Specifically, for example, as follows. That is, in the first manufacturing process SB1, for example, the transition piece 20 may be manufactured. As described above, the transition piece 20 is arranged so as to overlap the upper part of the monopile main body 10. Therefore, the transition piece 20 has a relatively high strength, and is less likely to change in shape before and after the structural analysis process SA3. For this reason, the transition piece 20 may be manufactured in the first manufacturing process SB1. Furthermore, in the first manufacturing process SB1, the interface flange IF of the transition piece 20 may not be manufactured, and instead a portion of the transition piece 20 other than the interface flange IF may be manufactured. The portion of the transition piece 20 other than the interface flange IF may be, for example, a side wall portion of the transition piece 20.

[0049] In this embodiment, at least one of the above-mentioned components is manufactured in the first manufacturing process SB1. Also, a plurality of the above-mentioned components may be manufactured in the first manufacturing process SB1. Specifically, for example, at least one of the monopile body 10, the transition piece 20, and the auxiliary equipment 30 may be manufactured in the latter first manufacturing process SB1c. Alternatively, all of the above-mentioned various components may be manufactured in the first manufacturing process SB1.

[0050] Here, multiple marine structures 1 present at the same installation site A may be installed one by one in sequence. Therefore, in this embodiment, the first fabrication process SB1 is preferably performed on at least one of the multiple marine structures 1 present at the same installation site A. That is, the first fabrication process SB1 is preferably performed only on the first marine structure 1 to be installed, or on several of the marine structures 1 to be installed initially. For marine structures 1 whose fabrication turn comes after the structural analysis process SA3 is completed, it is preferable to start fabrication after the structural analysis process SA3 is completed, without performing the first fabrication process SB1. This can prevent the need to redo fabrication of the marine structure 1, for example, when the shape of the marine structure 1 needs to be changed based on the results of the structural analysis process SA3.

[0051] The second manufacturing process SB2 is a process for manufacturing components of the marine structure 1 that were not manufactured in the first manufacturing process SB1 after the structural analysis process SA3 is completed. In the second manufacturing process SB2, it is preferable to manufacture components that do not require a long time for material procurement or manufacturing. In addition, the second manufacturing process SB2 may manufacture components whose shapes are determined relatively late in the structural analysis process SA3. This is preferable to prevent the need to remanufacture components due to changes in shape and to reduce costs.

[0052] The assembly process SB3 is a process for assembling the various members manufactured in the first manufacturing process SB1 and the second manufacturing process SB2. The assembly process SB3 may be performed, for example, at the same location as the factory where the first fabrication process SB1 and the second fabrication process SB2 were performed. In this case, the marine structure 1 may be transported to the installation site A and installed there after the assembly process SB3 is completed. Alternatively, the assembly process SB3 may be performed at the installation site of the marine structure 1. In this case, the marine structure 1 may be installed at the installation site A at the same time as it is assembled in the assembly process SB3. The process planning method according to this embodiment is carried out through the above steps.

[0053] The process planning method according to this embodiment may be implemented, for example, by a computer executing a program. In this case, all or part of the functions of the computer may be realized using hardware such as an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array). The program may be recorded on a computer-readable recording medium. Examples of computer-readable recording media include portable media such as flexible disks, magneto-optical disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into a computer system. The program may be transmitted via a telecommunications line.

[0054] As described above, the process planning method according to this embodiment includes a first fabrication process SB1 that is started after the completion of the earthquake response analysis included in the first structural analysis process SA3 but before the completion of the earthquake response analysis included in the second structural analysis process SA3, and that fabricates at least some of the components that make up the offshore structure 1 (monopile foundation). This allows the fabrication of the components to begin in advance in the first fabrication process SB1. Therefore, for example, the process of the construction project for the offshore structure 1 can be shortened compared to when fabrication of the offshore structure 1 is started after the completion of the structural analysis process SA3. This allows the offshore wind turbine WM to begin operation earlier. Furthermore, the first manufacturing process SB1 manufactures the transition piece 20. In the first manufacturing process SB1, the interface flange IF of the transition piece 20 is not manufactured, but the portion of the transition piece 20 other than the interface flange IF is manufactured. This shortens the waiting period for completion of the portion of the transition piece 20 other than the interface flange IF, thereby shortening the process of the construction project for the offshore structure 1. Furthermore, the interface flange IF of the transition piece 20 can more flexibly respond to changes in shape that occur in the structural analysis process SA3. In addition, the first manufacturing process SB1 manufactures the monopile body 10. In the first manufacturing process SB1, the connection portion of the monopile body 10 that is connected to the transition piece 20 in a state that overlaps it in a horizontal view is manufactured, and no portion of the monopile body 10 other than the connection portion is manufactured. This shortens the waiting period for the completion of the connection portion of the monopile body 10, and shortens the construction project process for the offshore structure 1. In addition, the portion of the monopile body 10 other than the connection portion can be more flexibly adapted to shape changes that occur in the structural analysis process SA3.

[0055] Furthermore, in the structural analysis step SA3, a structural analysis is performed using a model of the offshore structure 1. Then, in the first fabrication step SB1, at least some of the components that make up the offshore structure 1 are fabricated before the structural analysis step SA3 is completed. This allows the construction project for the offshore structure 1 to be shortened compared to, for example, a case in which fabrication of the offshore structure 1 begins after the structural analysis step SA3 is completed. Therefore, the offshore wind turbine WM can be started up earlier.

[0056] Furthermore, the first fabrication process SB1 fabricates some of the components that make up the marine structure 1. In this way, by fabricating some of the components that make up the marine structure 1 in the first fabrication process SB1 before the structural analysis process SA3 is performed, the process of the construction project for the marine structure 1 can be shortened.

[0057] Furthermore, the structural analysis step SA3 performs structural analysis of the model of the marine structure 1 only at predetermined diameter increments. In this way, by managing the diameters of the pipes used in the production of the marine structure 1 at predetermined diameter increments in accordance with the diameters for which structural analysis is performed, it is possible to easily manage pipe inventory. Specifically, for example, it is possible to prevent the occurrence of pipes of a diameter that are procured in advance but are not used in the production of the marine structure 1 as a result of the structural analysis, thereby preventing excess inventory. Furthermore, for example, the number of times that structural analysis is performed can be reduced compared to when structural analysis of the model of the marine structure 1 is performed for all possible diameters, thereby shortening the structural analysis step SA3.

[0058] Furthermore, the structural analysis step SA3 performs structural analysis of the model of the marine structure 1 only in predetermined plate thickness increments. In this way, by managing the thickness of the plates used in the production of the marine structure 1 in predetermined plate thickness increments in accordance with the plate thickness for which structural analysis is performed, it is possible to easily manage plate inventory. Specifically, for example, it is possible to prevent the occurrence of plates of a plate thickness that have been procured in advance but are not used in the production of the marine structure 1 due to the results of structural analysis, thereby preventing excess inventory. Furthermore, for example, the number of times the structural analysis is performed can be reduced compared to when the structural analysis of the model of the marine structure 1 is performed using all possible plate thicknesses, thereby shortening the structural analysis step SA3.

[0059] Furthermore, the first fabrication process SB1 fabricates components that are rate-limiting in the fabrication process of the marine structure 1. In this way, by fabricating the rate-limiting components in advance in the first fabrication process SB1, the process of the construction project for the marine structure 1 can be shortened.

[0060] Here, the shear key requires a relatively large amount of welding and can be a rate-limiting factor in the production of the offshore structure 1. Therefore, in the first production process SB1, components with shear keys are produced. In this way, by producing components with shear keys in the first production process SB1, which is carried out before the structural analysis process SA3, the waiting period for the completion of components with shear keys can be shortened (or eliminated), and the process of the construction project for the offshore structure 1 can be shortened.

[0061] The marine structure 1 also has auxiliary equipment 30. If the amount of welding for the auxiliary equipment 30 is large, this may become a rate-limiting factor in the fabrication of the marine structure 1. Therefore, the first fabrication process SB1 fabricates the auxiliary equipment 30. This shortens (or eliminates) the waiting period for the completion of the auxiliary equipment 30, thereby shortening the process of the marine structure 1 construction project.

[0062] The auxiliary facilities 30 are at least one of the mooring facilities 31, ladders 32, landings 33, working platforms 34, and passageways 35. This shortens (or eliminates) the waiting period for the completion of any of the mooring facilities 31, ladders 32, landings 33, working platforms 34, and passageways 35, thereby shortening the construction project schedule for the marine structure 1.

[0063] The marine structure 1 also has a transition piece 20. The transition piece 20 is positioned so as to overlap the upper part of the marine structure 1, thereby making it relatively strong. For this reason, the transition piece 20 is relatively unlikely to undergo changes in shape due to the analysis results of the marine structure 1. Therefore, the first manufacturing process SB1 manufactures the transition piece 20. This makes it easier to shorten the manufacturing period for the marine structure 1. Alternatively, the waiting period for the completion of the transition piece 20 can be shortened (or eliminated), thereby shortening the process of the construction project for the marine structure 1.

[0064] The transition piece 20 also has an interface flange IF. Because the interface flange IF requires corrosion protection, it can be a time-limiting step in the production of the offshore structure 1. Therefore, the first production process SB1 produces the interface flange IF. This shortens (or eliminates) the waiting period for the interface flange IF to be completed, thereby shortening the production process of the offshore structure 1 construction project.

[0065] The offshore structure 1 is a monopile foundation. The monopile foundation has a monopile body 10, and the first manufacturing process SB1 manufactures the monopile body 10. This shortens (or eliminates) the waiting period for the completion of the monopile body 10, and shortens the process of the construction project for the offshore structure 1.

[0066] Here, a relatively large bending moment may act on the portion of the monopile body 10 that is installed underground, and on the portion of that portion that is particularly close to the surface (seabed surface) of the seabed OF. For this reason, the portion of the monopile body 10 that is installed underground may need to have a larger plate thickness. This may lengthen the time required to weld the materials used in that portion, which may become a rate-limiting step in the fabrication of the offshore structure 1. Therefore, the first fabrication process SB1 fabricates the portion of the monopile body 10 that is installed underground. This shortens (or eliminates) the waiting period for the completion of the portion of the monopile body 10 that is installed underground, thereby shortening the process of the construction project for the offshore structure 1.

[0067] Furthermore, among the components constituting the marine structure 1, those not produced in the first production process SB1 are produced in the second production process SB2 after the completion of the structural analysis process SA3. This makes it possible to, for example, prevent changes to the shape of a component during production, which would otherwise require redoing the production. Also, for example, it makes it possible to prevent excess inventory from occurring, since materials procured in advance before the structural analysis process SA3 are not used in the production of the marine structure 1. This therefore reduces the amount of material used, and reduces the production costs of the marine structure 1.

[0068] Furthermore, the first fabrication process SB1 fabricates all of the components that make up the marine structure 1. This more reliably shortens the construction project process for the marine structure 1. Furthermore, for example, compared to when only some of the components that make up the marine structure 1 are fabricated in the first fabrication process SB1, it is easier to adjust the order in which each component is fabricated. This makes it easier to carry out the first fabrication process SB1 efficiently.

[0069] Here, multiple marine structures 1 present at the same installation location A may be installed one by one in sequence. Therefore, the first fabrication process SB1 is performed for at least one of the multiple marine structures 1 present at the same installation location A. This allows, for example, early fabrication of the marine structure 1 that is to be installed first among the multiple marine structures 1 to be started by the first fabrication process SB1. This makes it easier to shorten the period from the start of a construction project for the marine structure 1 to the start of installation of the marine structure 1.

[0070] The first fabrication process SB1 also includes a first pre-fabrication process SB1a and a first intermediate fabrication process SB1b, which are initiated before the start of the structural analysis process SA3, and a first post-fabrication process SB1c, which is initiated after the start of the structural analysis process SA3. This allows, for example, for the offshore structure 1, fabrication of components whose shapes have been determined before the start of the structural analysis process SA3 to begin in the first pre-fabrication process SB1a and the first intermediate fabrication process SB1b, while fabrication of other components can begin in the first post-fabrication process SB1c. This prevents fabrication of components containing uncertain elements from beginning before the structural analysis process SA3. This helps prevent the need to rework component fabrication due to changes in the shape of the offshore structure 1. This allows for optimized process planning. It also helps prevent cost increases.

[0071] The marine structure 1 is a monopile foundation. The monopile foundation has a transition piece 20 and an auxiliary equipment 30, and the first post-fabrication process SB1c fabricates at least one of the transition piece 20 and the auxiliary equipment 30. In this way, fabricating at least one of the transition piece 20 and the auxiliary equipment 30 in the first post-fabrication process SB1c, which is started after the start of the structural analysis process SA3, can help prevent the need to redo the fabrication of either the transition piece 20 or the auxiliary equipment 30.

[0072] The offshore structure 1 is a monopile foundation. The monopile foundation has a monopile body 10, and in the first fabrication process SB1, at least one of the inner and outer surfaces of the monopile body 10 is coated and protected from corrosion. This shortens the waiting period for the completion of the work of coating and protecting the monopile body 10, and shortens the construction project process for the offshore structure 1.

[0073] Furthermore, a construction planning method according to the present disclosure is applied to the offshore structure 1. This makes it possible to shorten the construction project schedule for the offshore structure 1. This allows the offshore wind turbine WM to begin operation earlier.

[0074] (Second embodiment) Next, a process planning method according to a second embodiment of the present disclosure will be described. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted, with only the differences being described.

[0075] In the second embodiment, in the first fabrication process SB1, for example, no components are fabricated that are not rate-limiting in the fabrication process of the marine structure 1. In this embodiment, not being rate-limiting means, for example, that there is little room to shorten the fabrication process of the marine structure 1 because it does not take a long time to procure, process, and assemble materials, and that there is a relatively high possibility that changes to the shape will occur in the structural analysis process SA3, so it is more preferable to start fabrication after the shape has been determined. In this way, for components that are not rate-limiting, by not manufacturing them in the first manufacturing process SB1, which is carried out before the completion of the structural analysis process SA3, manufacturing can begin after the shape has been determined. This prevents changes to the shape during manufacturing, which contributes to reducing the need to redo manufacturing. Below, we will explain several examples of members that are not rate-limiting in the process of manufacturing the marine structure 1. In this embodiment, it is preferable to appropriately select any of the members described below and not manufacture them in the first manufacturing process SB1.

[0076] In the second embodiment, for example, the transition piece 20 is not manufactured in the first manufacturing process SB1. The transition piece 20 is a component that accounts for a large proportion of the processing cost and the weight of the materials (e.g., steel) used in the marine structure 1. For this reason, the transition piece 20 may not be manufactured in the first manufacturing process SB1, but may be manufactured after the shape has been determined, thereby further reducing costs incurred by remanufacturing.

[0077] In the second embodiment, for example, the monopile body 10 may not be manufactured in the first manufacturing process SB1. The monopile body 10 is a component that accounts for a large proportion of the weight of the material (e.g., steel) used in the marine structure 1. For this reason, the monopile body 10 may not be manufactured in the first manufacturing process SB1, but may be manufactured after the shape has been determined, thereby further reducing costs incurred by re-manufacturing.

[0078] In the second embodiment, for example, at least one of the two end portions of the monopile body 10 may not be fabricated in the first fabrication process SB1. As described above, the monopile body 10 is formed by connecting a plurality of unit cylindrical bodies 11 in the longitudinal direction. In this case, the unit cylindrical bodies 11 located at positions other than the two end portions of the monopile body 10 are welded at both ends, whereas the unit cylindrical bodies 11 located at both ends of the monopile body 10 are welded at only one end. Therefore, the amount of welding at both end portions of the monopile body 10 is small, and this is unlikely to be a rate-limiting factor in the fabrication process. For this reason, by not fabricating at least one of the two end portions of the monopile body 10 in the first fabrication process SB1, it may be possible to more flexibly accommodate changes in the shape in the structural analysis process SA3.

[0079] In the second embodiment, for example, the auxiliary facilities 30 may not be fabricated in the first fabrication process SB1. The auxiliary facilities 30 are at least one of the mooring facilities 31, ladders 32, landings 33, working platforms 34, and walkways 35. These auxiliary facilities 30 are easily affected by the design results of major components of the marine structure 1 (for example, the transition piece 20), and therefore their shapes are likely to be changed in the structural analysis process SA3. For this reason, the auxiliary facilities 30 may not be fabricated in the first fabrication process SB1, but may be fabricated after the shape has been determined, thereby further reducing costs incurred by re-fabrication.

[0080] In the second embodiment, at least one of the above-mentioned components is not produced in the first manufacturing process SB1. Also, a plurality of the above-mentioned components may not be produced in the first manufacturing process SB1. Alternatively, all of the above-mentioned components may not be produced in the first manufacturing process SB1.

[0081] As described above, according to the process planning method of the second embodiment, the first manufacturing process SB1 does not manufacture components that are not rate-limiting in the manufacturing process of the marine structure 1. This makes it easier to flexibly respond to changes in the shape of the components that are not manufactured.

[0082] The marine structure 1 also has a transition piece 20. The transition piece 20 requires a relatively large amount of material and requires a relatively large amount of processing effort. Therefore, the first manufacturing process SB1 does not manufacture the transition piece 20. This allows manufacturing of the transition piece 20 to begin after the shape of the transition piece 20 has been optimized. This prevents changes to the shape of the transition piece 20 during manufacturing, making it easier to reduce the manufacturing costs of the marine structure 1.

[0083] Furthermore, the marine structure 1 is a monopile foundation, and the monopile foundation has a monopile body 10. The monopile body 10 uses a relatively large amount of material. Therefore, the first manufacturing process SB1 does not manufacture the monopile body 10. This allows the manufacturing of the monopile body 10 to begin after the shape of the monopile body 10 has been optimized. Therefore, it is possible to prevent changes to the shape of the monopile body 10 during manufacturing, and to easily reduce the manufacturing costs of the marine structure 1.

[0084] Here, the monopile body 10 is constructed by welding a plurality of unit tubular bodies 11 in the longitudinal direction. In this case, the unit tubular bodies 11 located at positions other than both ends of the monopile body 10 are welded at both ends, whereas the unit tubular bodies 11 located at both ends of the monopile body 10 are welded at only one end. Therefore, the amount of welding at both ends of the monopile body 10 is small, and this is relatively unlikely to be a rate-limiting step in the fabrication of the marine structure 1. Therefore, in the first fabrication process SB1, at least one of the both ends of the monopile body 10 is not fabricated. This makes it easier to flexibly respond to shape changes that occur in the member.

[0085] The marine structure 1 also has auxiliary equipment 30. The auxiliary equipment 30 is easily affected by the design results of major components of the marine structure 1 (for example, the transition piece 20), and therefore is prone to changes in shape. Therefore, the first manufacturing process SB1 does not manufacture the auxiliary equipment 30. This allows manufacturing of the auxiliary equipment 30 to begin after the shape of the auxiliary equipment 30 has been optimized. This prevents the auxiliary equipment 30 from being subject to shape changes during manufacturing, making it easier to keep manufacturing costs for the marine structure 1 down.

[0086] The auxiliary equipment 30 is at least one of the mooring equipment 31, ladder 32, landing 33, work floor 34, and passageway 35. This prevents changes to the shape of any of the mooring equipment 31, ladder 32, landing 33, work floor 34, and passageway 35 during fabrication, making it easier to keep the fabrication costs of the marine structure 1 down.

[0087] The technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure. For example, the process planning method according to this embodiment may be applied to structures other than the marine structure 1. Furthermore, in the structural analysis step SA3, the structural analysis of the model of the marine structure 1 may be performed not at predetermined diameter intervals or predetermined plate thickness intervals but at any diameter or plate thickness. Also, the first manufacturing process SB1 may not manufacture a member with a shear key. Furthermore, the marine structure 1 does not necessarily have to include the transition piece 20 . Furthermore, the marine structure 1 does not have to be a monopile foundation. In addition, in the first manufacturing process SB1, the portion of the monopile body 10 that is to be placed underground may not be manufactured. In addition, in the first manufacturing process SB1, one or both of the two end portions of the monopile body 10 may be manufactured. Furthermore, in the first fabrication process SB1, not all of the members that make up the marine structure 1 may be fabricated. Furthermore, the first fabrication process SB1 may be performed for two or more of the multiple marine structures 1 present at the same installation site A, or may be performed for all of them. Furthermore, the first manufacturing process SB1 does not necessarily have to include the intermediate first manufacturing process SB1b and the final first manufacturing process SB1c. Furthermore, in the first manufacturing process SB1, at least one of the inner and outer surfaces of the monopile body 10 does not need to be coated with anticorrosion coating.

[0088] In addition, within the scope of the present disclosure, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modified examples may be combined as appropriate.

[0089] (Addendum) The process planning method and marine structure according to the embodiment can be understood, for example, as follows.

[0090] <1> A process planning method according to one embodiment of the present disclosure is a process planning method for planning the process of a construction project for a monopile foundation having a monopile body and a transition piece and supporting the tower of an offshore wind turbine, the process comprising: a structural analysis process in which a computer performs a structural analysis of a model of the monopile foundation multiple times; and a first fabrication process that is started after completion of an earthquake response analysis included in a first structural analysis process but before completion of an earthquake response analysis included in a second structural analysis process, the first fabrication process fabricating at least some of the components that constitute the monopile foundation, wherein the first fabrication process fabricates the transition piece, does not fabricate an interface flange of the transition piece, and fabricates a portion of the transition piece other than the interface flange, and the first fabrication process fabricates the monopile body, and the first fabrication process fabricates a connection portion of the monopile body that is connected to the transition piece in a state that overlaps with the transition piece in a horizontal view, and does not fabricate a portion of the monopile body other than the connection portion.

[0091] According to the above process planning method, a first fabrication process is provided that is started after the completion of the earthquake response analysis included in the first structural analysis process and before the completion of the earthquake response analysis included in the second structural analysis process, and that fabricates at least some of the components that constitute the monopile foundation. This allows the fabrication of the components to begin in advance in the first fabrication process. Therefore, for example, compared to starting fabrication of the offshore structure after the structural analysis process is completed, the process of the offshore structure construction project can be shortened. This allows the offshore wind turbine to start operating earlier. In addition, the first fabrication process fabricates the transition piece. In the first fabrication process, the interface flange of the transition piece is not fabricated, but the portion of the transition piece other than the interface flange is fabricated. This shortens the waiting period for completion of the portion of the transition piece other than the interface flange, thereby shortening the process of the offshore structure construction project. In addition, the interface flange of the transition piece can more flexibly respond to shape changes that occur in the structural analysis process. In addition, the first manufacturing process manufactures the monopile body. In the first manufacturing process, the connection portion of the monopile body that is connected to the transition piece in a state where it overlaps horizontally is manufactured, and no other portion of the monopile body is manufactured. This shortens the waiting period for the completion of the connection portion of the monopile body, thereby shortening the process of the offshore structure construction project. In addition, the portion of the monopile body other than the connection portion can be more flexibly adapted to shape changes that occur during the structural analysis process.

[0092] <2> A process planning method according to one embodiment of the present disclosure is a process planning method for planning the process of a construction project for an offshore structure that supports the tower of an offshore wind turbine, and is characterized by comprising a structural analysis process for performing a structural analysis of a model of the offshore structure, and a first manufacturing process for manufacturing at least some of the components that make up the offshore structure before completion of the structural analysis process.

[0093] According to the above process planning method, in the structural analysis step, a structural analysis is performed using a model of the offshore structure. Then, in the first manufacturing step, at least some of the components constituting the offshore structure are manufactured before the structural analysis step is completed. This allows the construction project for the offshore structure to be shortened compared to, for example, a case in which manufacturing of the offshore structure begins after the structural analysis step is completed. Therefore, the offshore wind turbine can be started up sooner.

[0094] <3> the above <2> In the process planning method according to the above, the first manufacturing process may be configured to manufacture a part of a member that constitutes the marine structure.

[0095] In addition, the first fabrication process fabricates some of the components that make up the offshore structure. In this way, by fabricating some of the components that make up the offshore structure in the first fabrication process before the structural analysis process is performed, the process of the offshore structure construction project can be shortened.

[0096] <4> the above <2> or <3> In the process planning method according to the above, the structural analysis step may employ a configuration characterized in that structural analysis of the model of the marine structure is performed only at predetermined diameter intervals.

[0097] Furthermore, the structural analysis process performs structural analysis of the marine structure model only at predetermined diameter increments. In this way, by managing the diameters of the pipes used in the fabrication of the marine structure at predetermined diameter increments in accordance with the diameters for which structural analysis is performed, it is possible to easily manage pipe inventory. Specifically, for example, it is possible to prevent pipes of a diameter that are procured in advance but are not used in the fabrication of the marine structure due to the results of structural analysis, thereby preventing excess inventory. Furthermore, for example, the number of times structural analysis is performed can be reduced compared to when structural analysis of a marine structure model is performed for all possible diameters, thereby shortening the structural analysis process.

[0098] <5> the above <2> from <4> In the process planning method according to any one of the above aspects, the structural analysis step may employ a configuration characterized in that structural analysis of the model of the marine structure is performed only at predetermined plate thickness increments.

[0099] Furthermore, the structural analysis process performs structural analysis of the marine structure model only in predetermined thickness increments. In this way, by managing the thickness of plates used in the construction of the marine structure in predetermined thickness increments in accordance with the plate thickness for which structural analysis is performed, it is possible to easily manage plate inventory. Specifically, for example, it is possible to prevent the occurrence of plates of a thickness that are procured in advance but are not used in the construction of the marine structure due to the results of structural analysis, thereby preventing excess inventory. Furthermore, for example, the number of times structural analysis is performed can be reduced compared to when structural analysis of a marine structure model is performed using all possible plate thicknesses, thereby shortening the structural analysis process.

[0100] <6> the above <2> from <5> In the process planning method according to any one of the above aspects, the first manufacturing process may be configured to manufacture a member that is rate-limiting in the manufacturing process of the marine structure.

[0101] In addition, the first fabrication process is used to fabricate components that are rate-limiting in the fabrication of the offshore structure. By fabricating rate-limiting components in advance in the first fabrication process, the construction project for the offshore structure can be shortened.

[0102] <7> the above <2> from <6> In the process planning method according to any one of the above aspects, the first manufacturing process may be configured to manufacture a member having a shear key attached thereto.

[0103] Here, shear keys require a relatively large amount of welding, which can be a time-limiting factor in the fabrication of offshore structures. Therefore, the first fabrication process fabricates components with shear keys. In this way, by fabricating components with shear keys in the first fabrication process, which is carried out before the structural analysis process, the waiting time for the completion of components with shear keys can be shortened, thereby shortening the process of offshore structure construction projects.

[0104] <8> the above <2> from <7> In the process planning method according to any one of the above aspects, the marine structure may have auxiliary equipment, and the first manufacturing process may be configured to manufacture the auxiliary equipment.

[0105] Furthermore, marine structures have auxiliary equipment. If the auxiliary equipment requires a large amount of welding, this can become a time-limiting step in the fabrication of the marine structure. Therefore, the first fabrication process is to fabricate the auxiliary equipment. This shortens the waiting period for the auxiliary equipment to be completed, thereby shortening the construction project schedule for the marine structure.

[0106] <9> the above <8> In the process planning method according to the above, the auxiliary facilities may be at least one of mooring facilities, ladders, landings and work platforms, and walkways.

[0107] The auxiliary facilities are at least one of mooring facilities, ladders, landings and work platforms, and gangways, thereby shortening the waiting period for the completion of any of the mooring facilities, ladders, landings and work platforms, and gangways, and shortening the construction schedule of the offshore structure project.

[0108] <10> the above <2> from <9> In the process planning method according to any one of the above aspects, the marine structure may have a transition piece, and the first manufacturing process may be configured to manufacture the transition piece.

[0109] The offshore structure also has a transition piece. The transition piece is placed so as to overlap the upper part of the offshore structure, which makes it relatively strong. For this reason, the transition piece is relatively unlikely to undergo shape changes due to the analysis results of the offshore structure. Therefore, the first manufacturing process is to manufacture the transition piece. This makes it easier to shorten the manufacturing period of the offshore structure. Alternatively, it can shorten the waiting period for the completion of the transition piece and shorten the process of the offshore structure construction project.

[0110] <11> the above <10> In the process planning method according to the above, the transition piece may have an interface flange, and the first manufacturing process may be configured to manufacture the interface flange.

[0111] The transition piece also has an interface flange. Because the interface flange requires corrosion protection, it can be a time-limiting step in the fabrication of offshore structures. Therefore, the first fabrication step is to fabricate the interface flange. This shortens the waiting time for the interface flange to be completed, thereby shortening the construction project schedule for the offshore structure.

[0112] <12> the above <2> from <11> In any one of the above process planning methods, the marine structure may be a monopile foundation, the monopile foundation may have a monopile body, and the first manufacturing process may be configured to manufacture the monopile body.

[0113] The offshore structure is a monopile foundation. The monopile foundation has a monopile body, and the first manufacturing process is to manufacture the monopile body. This shortens the waiting period for the completion of the monopile body and shortens the construction process of the offshore structure.

[0114] <13> the above <12> In the process planning method according to the above, the first manufacturing process may be configured to manufacture a portion of the monopile body that is to be installed underground.

[0115] Here, a relatively large bending moment may act on the portion of the monopile body that is installed underground, especially on the portion of that portion close to the seabed. For this reason, the portion of the monopile body that is installed underground may need to have a larger plate thickness. This increases the time required to weld the materials used in that portion, which may become a rate-limiting factor in the fabrication of the offshore structure. Therefore, the first fabrication process fabricates the portion of the monopile body that is installed underground. This shortens the waiting time for the completion of the portion of the monopile body that is installed underground, thereby shortening the construction project schedule for the offshore structure.

[0116] <14> the above <2> from <13> In any one of the above process planning methods, a configuration may be adopted in which a second manufacturing process is provided in which components constituting the marine structure that are not manufactured in the first manufacturing process are manufactured after the structural analysis process is completed.

[0117] Furthermore, among the components constituting the marine structure, those not produced in the first production process are produced in the second production process after the structural analysis process is completed. This makes it easier to prevent, for example, changes in the shape of a component occurring during production, which requires redoing the production. Also, for example, it makes it easier to prevent excess inventory from occurring, as materials procured in advance before the structural analysis process are not used in the production of the marine structure. This therefore reduces the amount of material used and the production costs of the marine structure.

[0118] <15> the above <2> from <14> In the process planning method according to any one of the above aspects, the first manufacturing process may be configured not to manufacture components that are not rate-limiting in the manufacturing process of the marine structure.

[0119] Furthermore, the first manufacturing process does not manufacture components that are not rate-limiting in the manufacturing process of the marine structure, which makes it easier to flexibly respond to changes in the shape of the components that are not manufactured.

[0120] <16> the above <2> from <15> In the process planning method according to any one of the above aspects, the marine structure may have a transition piece, and the first manufacturing process may be configured not to manufacture the transition piece.

[0121] The offshore structure also has a transition piece. The transition piece requires a relatively large amount of material and a relatively large amount of processing effort. Therefore, the first manufacturing process does not involve manufacturing the transition piece. This allows manufacturing of the transition piece to begin after the shape of the transition piece has been optimized. This prevents changes to the shape of the transition piece during manufacturing, making it easier to reduce the manufacturing costs of the offshore structure.

[0122] <17> the above <2> from <16> In any one of the above process planning methods, the marine structure may be a monopile foundation, the monopile foundation may have a monopile body, and the first manufacturing process may be configured not to manufacture the monopile body.

[0123] Furthermore, the offshore structure is a monopile foundation, and the monopile foundation has a monopile body. The monopile body uses a relatively large amount of material. Therefore, the first manufacturing process does not manufacture the monopile body. This allows manufacturing of the monopile body to begin after the shape of the monopile body has been optimized. Therefore, it is possible to prevent changes to the shape of the monopile body during manufacturing, and to easily reduce the manufacturing costs of the offshore structure.

[0124] <18> the above <17> In the process planning method according to the above, the first manufacturing process may employ a configuration characterized in that at least one of both end portions of the monopile body is not manufactured.

[0125] Here, the monopile body is constructed by welding multiple raw pipes (blank pipes) longitudinally. In this process, the blank pipes located at the ends of the monopile body are welded at both ends, whereas the blank pipes located at both ends of the monopile body are welded at only one end. Therefore, the amount of welding at both ends of the monopile body is small, and this is relatively unlikely to be a rate-limiting step in the fabrication of marine structures. Therefore, in the first fabrication process, at least one of the ends of the monopile body is not fabricated. This makes it easier to flexibly respond to shape changes that occur in the component.

[0126] <19> the above <2> from <18> In the process planning method according to any one of the above aspects, the marine structure may have auxiliary equipment, and the first manufacturing process may be configured to not manufacture the auxiliary equipment.

[0127] Furthermore, the marine structure has auxiliary equipment. The auxiliary equipment is easily affected by the design results of the main components of the marine structure (e.g., transition pieces), and therefore changes in shape are likely to occur. Therefore, the first manufacturing process does not manufacture the auxiliary equipment. This allows the manufacturing of the auxiliary equipment to begin after the shape of the auxiliary equipment has been optimized. This prevents the occurrence of shape changes in the auxiliary equipment during manufacturing, making it easier to reduce the manufacturing costs of the marine structure.

[0128] <20> the above <19> In the process planning method according to the above, the auxiliary facilities may be at least one of mooring facilities, ladders, landings and work platforms, and walkways.

[0129] The auxiliary facilities are at least one of mooring facilities, ladders, landings and work platforms, and walkways. This prevents changes to the shape of any of the mooring facilities, ladders, landings and work platforms, or walkways during fabrication, making it easier to reduce the fabrication costs of marine structures.

[0130] <21> the above <2> from <20> In the process planning method according to any one of the above aspects, the first manufacturing process may be configured to manufacture all of the members that constitute the marine structure.

[0131] Furthermore, the first manufacturing process manufactures all of the components that make up the marine structure. This makes it possible to more reliably shorten the process of the marine structure construction project. Furthermore, for example, compared to when only some of the components that make up the marine structure are manufactured in the first manufacturing process, it is easier to adjust the order in which each component is manufactured. This makes it easier to carry out the first manufacturing process efficiently.

[0132] <22> the above <2> from <21> In any one of the above process planning methods, the first manufacturing process may be performed on at least one of a plurality of the marine structures located in the same wind farm or sea area.

[0133] Here, multiple offshore structures located in the same wind farm or sea area may be installed one by one in sequence. Therefore, the first fabrication process is performed for at least one of the multiple offshore structures located in the same wind farm or sea area. This allows, for example, early start of fabrication for an offshore structure that will be installed first among the multiple offshore structures through the first fabrication process. This makes it easier to shorten the period from the start of an offshore structure construction project to the start of installation of the offshore structure.

[0134] <23> the above <2> from <22> In the process planning method according to any one of the above aspects, the first manufacturing process may be configured to include a first pre-manufacturing process and a first middle-manufacturing process that are started before the structural analysis process begins, and a first post-manufacturing process that is started after the structural analysis process begins.

[0135] The first manufacturing process includes a first pre-manufacturing process and a first intermediate manufacturing process that are started before the start of the structural analysis process, and a first post-manufacturing process that is started after the start of the structural analysis process. This allows, for example, for an offshore structure, manufacturing of components whose shapes have been determined before the start of the structural analysis process to begin in the first pre-manufacturing process and the first intermediate manufacturing process, while manufacturing of other components can begin in the first post-manufacturing process. This prevents components containing uncertain elements from starting manufacturing before the structural analysis process. This helps prevent the need to redo the manufacturing of components due to changes in the shape of the offshore structure. This allows for an optimized process plan. It also helps prevent increases in costs.

[0136] <24> the above <23> In the process planning method according to the above, the marine structure may be a monopile foundation, the monopile foundation having a transition piece and auxiliary equipment, and the first subsequent manufacturing process may be configured to manufacture at least one of the transition piece and the auxiliary equipment.

[0137] The marine structure is a monopile foundation. The monopile foundation has a transition piece and an attachment, and at least one of the transition piece and the attachment is fabricated in the post-first fabrication process. In this way, fabricating at least one of the transition piece and the attachment in the post-first fabrication process, which is started after the start of the structural analysis process, can help prevent the need to redo the fabrication of either the transition piece or the attachment.

[0138] <25> the above <2> from <24> In any one of the process planning methods, the marine structure may be a monopile foundation, the monopile foundation having a monopile body, and in the first manufacturing process, at least one of the inner and outer surfaces of the monopile body may be coated and corrosion-protected.

[0139] The offshore structure is a monopile foundation. The monopile foundation has a monopile body, and in the first manufacturing process, at least one of the inner and outer surfaces of the monopile body is coated and protected against corrosion. This shortens the waiting period for the completion of the work of coating and protecting the monopile body, and shortens the process of the offshore structure construction project.

[0140] <26> The marine structure according to one aspect of the present disclosure is <1> from <25> The process planning method according to any one of the above aspects is applied.

[0141] Furthermore, the process planning method according to the present disclosure is applied to the offshore structure according to the present disclosure, which allows the process of the offshore structure construction project to be shortened, thereby enabling the offshore wind turbine to start operation earlier. [Explanation of symbols]

[0142] 1 Marine structures 10 Monopile body 11 Unit cylindrical body 11A board 20 Transition Piece 30 Ancillary Equipment 31 Mooring equipment 32 Ladder 33 Landing 34 Work Platform 35 Passage A. Installation location B Bolt C Cable DC Davit Crane G Grout H hole IF Interface Flange OF ocean floor SA design review flow SA1 Preliminary survey process SA2 Shape review process SA3 Structural analysis process SA3a Analysis Implementation Steps SA3b First confirmation step SA3c 2nd confirmation step SA3d 3rd confirmation step SA3e Review Steps SB production flow SB1 1st production process SB1a first production process SB1b Middle 1st production process SB1c 1st production process SB2 2nd production process SB3 assembly process T Tower WM Offshore Wind Turbine

Claims

[Claim 1] A process planning method for planning a process for a construction project of a monopile foundation that supports a tower of an offshore wind turbine, the monopile foundation having a monopile body and a transition piece, comprising: a structural analysis step in which a computer performs a structural analysis of the monopile foundation model multiple times; a first fabrication process that is started after completion of an earthquake response analysis included in a first structural analysis process and before completion of an earthquake response analysis included in a second structural analysis process, and that fabricates at least some of the members that constitute the monopile foundation; Equipped with the first manufacturing step is to manufacture the transition piece; The first manufacturing step does not manufacture an interface flange of the transition piece, and manufactures a portion of the transition piece other than the interface flange, The first manufacturing step includes manufacturing the monopile body, The first manufacturing process is a process planning method in which a connection portion of the monopile body is manufactured that is connected to the transition piece in a state that overlaps it horizontally, and no portion of the monopile body other than the connection portion is manufactured.

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