Work barge

Abstract

To provide a technology capable of confirming the state of a riprap foundation under construction without relying on divers.SOLUTION: A work barge is used for the confirmation work of the construction state of a riprap foundation when the construction of the riprap foundation on the seabed is carried out. The work barge comprises a measuring device to measure the seabed and a display device to display the measured result of the seabed by the measuring device on a display. In the work barge, an opening part allowing the view outside the ship from inboard is formed on the outer hull of a ship bottom part and a transparent plate to close the whole opening part is attached to the outer hull with this opening part formed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to a technique for allowing workers to confirm the construction state of a rubble foundation on the seabed.

Background Art

[0002] Port structures (offshore wind turbines, breakwaters, etc.) are constructed on top of a rubble foundation built on the seabed. The rubble foundation is constructed by forming a rubble mound on the seabed and ramming this rubble mound.

[0003] The rubble mound is formed by depositing rubble thrown from the sea side onto the seabed, as shown in, for example, Patent Document 1. Also, the rubble foundation is constructed by ramming the rubble mound formed on the seabed with a heavy weight, as shown in, for example, Patent Document 2.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in order to construct the rubble foundation as designed, it is necessary to confirm the state of the rubble foundation being constructed at an appropriate timing. For example, in the work process for forming the rubble mound, the presence or absence of portions where the rubble deposited on the seabed is higher than the designed height or lower than the designed height is confirmed. That is, the locations where the rubble deposited on the rubble mound is to be removed (portions where the rubble deposited on the seabed is higher than the designed height) and the locations where additional rubble is to be added to the rubble mound (portions where the rubble deposited on the seabed is lower than the designed height) are confirmed.

[0006] In addition, for example, in the work process of tamping the top surface or slope surface of the riprap mound, confirmation of the presence or absence of insufficient tamping and confirmation of whether the riprap foundation is constructed as designed are carried out.

[0007] Conventionally, the state of the riprap foundation being constructed has been confirmed by a diver diving into the sea. That is, a diver diving into the sea visually confirmed the state of the riprap foundation being constructed.

[0008] Recently, the number of cases of constructing riprap foundations in deep water areas has been increasing, and the depth at which divers dive tends to be deeper. Also, the number of divers is decreasing, making it difficult to arrange divers to confirm the state of the riprap foundation being constructed, and the construction period for the riprap foundation may become longer.

[0009] For these reasons, a method that can confirm the state of the riprap foundation being constructed without relying on divers is required.

[0010] An object of the present invention is to provide a technique that can confirm the state of a riprap foundation being constructed without relying on divers.

Means for Solving the Problems

[0011] The workboat of the present invention is configured as follows in order to achieve the above object.

[0012] The workboat according to the present invention is used for the confirmation work of the construction state of a riprap foundation when the construction of the riprap foundation on the seabed is being carried out.

[0013] The surveying device surveys the seabed. The surveying device is, for example, a known sonar device. By the surveying device, the riprap foundation being constructed on the seabed can be surveyed.

[0014] The display device causes the display to show the seabed measurement results obtained by the surveying device. Therefore, on the display, the shape, size, etc. of the rubble mound foundation being constructed on the seabed are shown as the measurement results obtained by the surveying device. That is, the worker can confirm the construction state of the rubble mound foundation being constructed based on the measurement results of the surveying device shown on the display.

[0015] In addition, an opening through which the outside of the ship can be seen from inside the ship is formed in the outer plate at the bottom of the ship. This opening is formed in a portion located below the sea surface (i.e., underwater) when the work ship is floating on the sea.

[0016] Also, a transparent plate that closes the entire opening is attached to the outer plate in which the opening is formed. When the work ship is floating on the sea, sea water does not enter the ship through the opening. The transparent plate may be an acrylic plate, tempered glass, or other member as long as it has a certain transmittance (e.g., a transmittance of 50% or more). However, the transparent plate has a thickness that can ensure strength against water pressure and the like.

[0017] The worker can visually confirm the construction state (shape, size, etc.) of the rubble mound foundation being constructed through the opening.

[0018] Therefore, the worker can confirm the construction state of the rubble mound foundation based on the measurement results of the surveying device shown on the display and visual confirmation. By using this work ship, it is possible to confirm the state of the rubble mound foundation being constructed without relying on divers.

[0019] In addition, the work ship may be equipped with, for example, a positioning device that positions the ship's own position, and the display device may be configured to convert the seabed measurement results obtained by the surveying device based on the position of the ship's own position measured by the positioning device and display the converted measurement results on the display.

[0020] With this configuration, it is also possible to confirm the absolute position (e.g., latitude, longitude, altitude) of the rubble mound foundation being constructed from the measurement results shown on the display.

[0021] In addition, for the workboat, for example, a confirmation workroom for workers to enter to check the construction status of the rubble foundation is provided at the bottom of the hull. This confirmation workroom may be a space where an opening formed in the outer plate is located. In this case, the confirmation workroom may be a space partitioned by a partition wall. The partition wall may have a first partition wall and a second partition wall, and the first partition wall and the second partition wall may be arranged to face each other with a gap therebetween. With such a configuration, even when the transparent plate is damaged due to some impact, the flooded area where seawater intrudes can be suppressed in the confirmation workroom.

[0022] In addition, the confirmation workroom may be provided, for example, on the bow side, on the starboard side, or on the port side.

[0023] In addition, the workboat may be a crane barge equipped with a crane. This crane may be used in the process of throwing rubble from the sea side to the seabed and depositing the rubble on the seabed, or may be used in the process of lifting a weight and dropping the lifted weight onto a rubble mound formed by the rubble deposited on the seabed to compact this rubble mound, or may be used in these two processes.

[0024] In addition, for example, a plurality of the openings may be formed in the outer plate, and the plurality of the openings may be closed by a single transparent plate. With such a configuration, the pressure applied to the transparent plate can be suppressed, and the risk of the transparent plate being damaged can be reduced.

Advantages of the Invention

[0025] According to this invention, the status of the rubble foundation under construction can be confirmed without relying on divers.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0027] Hereinafter, embodiments of the present invention will be described.

[0028] Figs. 1(A) and (B) are schematic views showing a crane barge for constructing a riprap foundation on the seabed. Fig. 1(A) is a schematic view when performing the step of forming a riprap mound on the seabed, and Fig. 1(B) is a schematic view when performing the step of ramming the riprap mound formed on the seabed.

[0029] In this example, the crane barge 1 corresponds to the workboat referred to in the present invention. The crane barge 1 is equipped with a crane 2. In this example, the crane 2 is attached to the bow side of the crane barge 1.

[0030] Note that the crane 2 may be attached to the stern side of the crane barge 1 or may be attached in the middle between the bow and the stern.

[0031] As shown in Fig. 1(A), when performing the step of forming a riprap mound on the seabed, the grab bucket 3 is attached to the wire of the crane 2. Also, as shown in Fig. 1(B), when performing the step of ramming the riprap mound formed on the seabed, the weight 4 is attached to the wire of the crane 2. In Fig. 1(B), the weight 4 for ramming the top end surface of the riprap mound is attached to the wire of the crane 2.

[0032] The steps for constructing a rubble mound foundation include a step of depositing rubble on the seabed to form a rubble mound, and a step of ramming the top surface and the side surface of the formed rubble mound. For the step of forming the rubble mound and the step of ramming the top surface and the side surface of the rubble mound, various methods (for example, the methods shown in Patent Document 1 and Patent Document 2 described above) are known. In this example, any known method may be used for the method of the step of forming the rubble mound and the method of the step of ramming the top surface and the side surface of the rubble mound. In other words, in this example, the rubble mound may be formed on the seabed by any method, and the top surface and the side surface of the rubble mound may be rammed by any method.

[0033] For example, the rubble used to form the rubble mound is loaded on the crane barge 1. The crane 2 grabs the rubble loaded on the crane barge 1 with the grab bucket 3 and forms the rubble mound on the seabed by throwing the grabbed rubble into the sea from the sea side. Further, the crane 2 rams the top surface and the side surface of the rubble mound formed on the seabed by dropping the weight 4.

[0034] The crane barge 1 is provided with an inspection workroom 10 on the bow side. This inspection workroom 10 is a space (room) where an operator can check the shape, size, etc. of the rubble mound formed on the seabed and the state of the rubble mound foundation being constructed by ramming the top surface and the side surface of the rubble mound formed on the seabed.

[0035] Figure 2 is a diagram showing the connection of the main equipment installed on the crane barge. The crane barge 1 in this example is equipped with a surveying device 11, a positioning device 12, an integration device 13, and a display 14.

[0036] The surveying device 11 surveys the seabed with the position of the own ship as the reference position. The surveying device 11 is, for example, a known sonar device. By surveying the seabed, the surveying device 11 obtains the shape, size, etc. of the rubble mound and the rubble foundation formed on the seabed. The surveying device 11 outputs the survey result of the seabed to the integration device 13.

[0037] The positioning device 12 measures the absolute position (latitude, longitude, altitude) of the own ship. The positioning device 12 is, for example, a known GPS (Global Positioning System) device. The positioning device 12 outputs the positioning result (the absolute position of the own ship) to the integration device 13.

[0038] Based on the survey result of the survey device 11 and the positioning result of the positioning device 12, the integration device 13 calculates the absolute position of the rubble mound or rubble foundation formed on the seabed. The integration device 13 generates screen data indicating the absolute position, shape, size, etc. of the rubble mound or rubble foundation formed on the seabed, and outputs it to the display 14. The integration device 13 corresponds to the display device referred to in this invention.

[0039] The display 14 displays a screen according to the screen data output by the integration device 13.

[0040] The display 14 is installed in the confirmation workroom 10. The survey device 11, the positioning device 12, and the integration device 13 may be installed in the confirmation workroom 10, or may be installed in other locations. However, the survey sensor (for example, an ultrasonic sensor) used by the survey device 11 to survey the seabed is attached to a place where the seabed can be surveyed, and the positioning sensor (for example, a GPS sensor) used by the positioning device 12 to measure the position of the own ship is attached to a place where it is easy to receive GPS signals from satellites.

[0041] Next, the confirmation workroom 10 will be described. As shown in FIG. 1, the crane barge 1 in this example is provided with a confirmation workroom 10 at the bottom of the ship's bow. FIG. 3 is a schematic cross-sectional view of the confirmation workroom in the longitudinal direction of the entire length of the crane barge. The confirmation workroom 10 is a space where the bow side faces the outer plate 21 of the crane barge 1. The confirmation workroom 10 is a space where the surface that does not face the outer plate 21 is partitioned by a partition wall.

[0042] The side surface (excluding the surface facing the outer plate 21) and the ceiling partition wall of the inspection workroom 10 shown in FIG. 3 have a double-wall structure. Specifically, the side surface (excluding the surface facing the outer plate 21) and the ceiling of the inspection workroom 10 are partitioned by a partition wall in which an outer partition wall 25 and an inner partition wall 26 are arranged opposite to each other with a gap therebetween. The outer partition wall 25 and the inner partition wall 26 are arranged opposite to each other with a gap of about 1 m, for example. The space between the opposed outer partition wall 25 and inner partition wall 26 is herein referred to as an air chamber.

[0043] Note that the inspection workroom 10 may also have a double-wall structure for the floor surface.

[0044] FIG. 4 is a schematic plan view of the outer plate of the portion where the inspection workroom is located as viewed in the longitudinal direction of the crane barge from the bow side of the crane barge. An opening 21a is formed in the outer plate 21 located inside the inspection workroom 10. Further, a transparent plate 22 that closes the entire opening 21a is attached. The transparent plate 22 may be an acrylic plate, tempered glass, or other member as long as it has a certain light transmittance (for example, a light transmittance of 50% or more). However, the transparent plate 22 has a thickness that can ensure a certain strength against water pressure (strength that is not damaged by the water pressure applied during normal navigation). For example, the transparent plate 22 has a thickness of several cm (for example, about 3 to 7 cm). Also, the size of the transparent plate 22 is such that the longitudinal length is several m (1 to 3 m) and the transverse length is several m (1 to 3 m). The longitudinal length and the transverse length of the transparent plate 22 may be the same or different. Here, an example is shown in which the outer shape of the transparent plate 22 is rectangular, but other shapes such as circular may also be possible.

[0045] In addition, the door 25a shown in FIG. 3 opens and closes the passage for workers entering and leaving between the outside of the inspection workroom 10 and the air chamber. Also, the door 26a shown in FIG. 3 opens and closes the passage for workers entering and leaving between the inside of the inspection workroom 10 and the air chamber. For example, a worker entering and leaving the inspection workroom 10 from the outside opens and closes the door 25a to enter the air chamber, and then opens and closes the door 26a to enter the inspection workroom 10. The doors 25a and 26a preferably are equipped with a so-called door closer to prevent the worker from forgetting to close them. As is well known, a door closer moves the doors 25a and 26a, which are in the open state, to the closed state.

[0046] A worker who has entered the inspection workroom 10 can visually observe the riprap mound formed on the seabed and the riprap foundation constructed on the seabed through the transparent plate 22 and the opening 21a. That is, the worker can visually confirm the state of the riprap mound formed on the seabed and the riprap foundation constructed on the seabed in the inspection workroom 10.

[0047] FIG. 5 is a diagram for explaining a state in which a visual inspection of the riprap mound formed on the seabed is performed. In the crane barge 1 of this example, since the inspection workroom 10 is provided on the bow side, the bow is opposed to the riprap mound for visual inspection. A worker who has entered the inspection workroom 10 visually observes the riprap mound through the transparent plate 22 that closes the opening 21a. The worker confirms the portions where the riprap deposited on the surface of the riprap mound is sunken or protruding.

[0048] The surveying device 11 surveys the seabed with the position of the crane barge 1 (surveying sensor) as a reference position. The positioning device 12 measures the absolute position (latitude, longitude, altitude) of the crane barge 1 (positioning sensor). Since the attachment position of the surveying sensor on the crane barge 1 and the attachment position of the positioning sensor on the crane barge 1 are known, the absolute position of the surveying sensor of the crane barge 1 can be obtained from the positioning result of the positioning device 12.

[0049] The integrated device 13 displays on the screen of the display 14 the absolute position, shape, size, etc. of the riprap mound formed on the seabed based on the survey results of the survey device 11 and the positioning results of the positioning device 12. For example, an image in which the absolute position is superimposed on the seabed topography measured by the survey device 11 is displayed on the screen of the display 14.

[0050] Therefore, the operator can check on the screen of the display 14 the locations where the riprap deposited on the riprap mound visually observed through the transparent plate 22 closing the opening 21a is felt to be sunken or protruding. Also, the operator can check from the seabed topography displayed on the screen of the display the locations where the formed riprap mound has unevenness, and can carefully visually confirm the locations where the confirmed unevenness occurs through the transparent plate 22 closing the opening 21a. Therefore, the operator can easily and accurately visually check the state of the riprap mound in the inspection workroom 10 of the crane barge 1.

[0051] In the above description, the visual inspection of the riprap mound by the operator was described as an example, but similarly, even for the top surface of the riprap mound and the riprap foundation where the side surfaces are butted, the operator can easily and accurately visually check the state of the riprap foundation in the inspection workroom 10 of the crane barge 1.

[0052] Also, since the inspection workroom 10 is a space partitioned by a double-wall structure partition, when the transparent plate 22 closing the opening 21a is damaged, the flooded area where seawater enters can be suppressed within the inspection workroom 10.

[0053] As described above, the crane barge 1 in this example can allow the operator who enters the inspection workroom 10 to visually check the state of the riprap mound and the riprap foundation. Therefore, the confirmation of the state of the riprap foundation under construction can be performed without relying on divers.

[0054] Further, as shown in FIG. 6, a plurality of openings 21b may be formed in the outer plate 21 located within the inspection workroom 10. In this case, a transparent plate 22 for closing each opening 21b may be provided, but as shown in FIG. 6, all the openings 21b may be closed with a single transparent plate 22.

[0055] Note that the arrangement of the plurality of openings 21b shown in FIG. 6 is merely an example, and any other arrangement may be used.

[0056] Also, in the above description, the inspection workroom 10 is provided on the bow side of the crane barge 1, but it may be provided on the starboard or port side.

[0057] Moreover, the workboat according to the present invention is not limited to the crane barge 1 described in the above example, and may be any type of ship (for example, a stone-throwing barge).

[0058] Also, the partition wall that partitions the inspection workroom 10 does not have to be a double-wall structure. Further, the space where the opening 21a formed in the outer plate 21 is located may be a space not partitioned by the partition wall.

[0059] Note that the present invention is not limited to the above-described embodiment as it is, and at the implementation stage, the components can be modified and embodied without departing from the gist thereof. Also, various inventions can be formed by appropriately combining the plurality of components disclosed in the above embodiment. For example, some of the components shown in the embodiment may be deleted.

Explanation of Reference Numerals

[0060] 1... Crane barge 2... Crane 3... Grab bucket 4... Plumb bob 10... Inspection workroom 11... Measuring device 12... Positioning device 13... Integration device 14... Display 21... Outer plate 21a, 21b... Openings 22… transparent plate 25… outer partition wall 26… inner partition wall 25a, 26a… door

Claims

1. A workboat used for checking the construction state of a rubble foundation when the construction of the rubble foundation on the seabed is being carried out, a surveying device for surveying the seabed, and a display device for displaying the seabed survey result obtained by the surveying device on a display, and an opening through which the outside of the ship can be seen from inside the ship is formed in the outer plate at the bottom of the ship, A transparent plate covering the entire opening is attached to the outer plate where the opening is formed. Workboat.

2. Equipped with a positioning device for positioning the position of its own ship, The display device converts the seabed survey result obtained by the surveying device based on the position of its own ship measured by the positioning device, and displays the converted survey result on the display. The workboat according to claim 1.

3. A confirmation workroom for workers to enter to check the construction state of the rubble foundation is provided at the bottom of the ship, The confirmation workroom is a space where the opening formed in the outer plate is located. The workboat according to claim 1.

4. The confirmation workroom is a space partitioned by a partition wall, The partition wall has a first partition wall and a second partition wall, and the first partition wall and the second partition wall are arranged opposite to each other with a gap therebetween. The workboat according to claim 3.

5. The confirmation workroom is provided on the bow side. The workboat according to claim 3 or 4.

6. Equipped with a crane for throwing rubble from the sea side to the seabed and depositing the rubble on the seabed. The workboat according to any one of claims 1 to 4.

7. Equipped with a crane for lifting a weight and dropping the lifted weight onto a rubble mound formed by the rubble deposited on the seabed to compact the rubble mound. The workboat according to any one of claims 1 to 4.

8. A plurality of the openings are formed in the outer plate, The workboat according to any one of claims 1 to 4, wherein the plurality of the openings are closed by one transparent plate.

Images