JP2010064649A - Taut mooring float and method for towing and installing taut mooring float - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a taut mooring float and a towing and installation method for a taut mooring float, securing stability by increasing static restoring force of the taut mooring float in towing and installing the taut mooring float to thereby decrease the required capability and use frequency of a large-sized ocean crane, besides performing the fitting work and length adjusting work for a taut mooring rope above the water surface in installation and after the installation. <P>SOLUTION: In this taut mooring float 1, a float 12 having a columnar body 12a penetrating through the water surface 3 and a submerged buoyancy body 12b and a lower mooring part 14c installed at the bottom of the sea are connected to one another by a plurality of taut mooring ropes 13, and tension is applied to the taut mooring ropes 13 to hold the position of the taut mooring float. A mooring member 15 having a water surface penetrating buoyancy part is connected to the submerged buoyancy body 12b, and the upper end of the taut mooring rope 13 is fixed to an upper mooring part 15c provided above the water surface of the mooring member 15. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention improves static restoration performance during towing and installation of a tension mooring floating body used as a pedestal for a wind power generator or the like, and after installation, the tension mooring cable is fixed and adjusted in length above the water surface. It is related with the towing and installation method of a tension mooring floating body and the tension mooring floating body which can improve workability | operativity by carrying out by.

  With regard to wind power generation, proposals have been made to install a tension mooring floating body (TLP: tension leg platform) on the continental shelf on the coast and to mount a device such as a wind power generator on the tension mooring floating body. For example, as shown in FIG. 6, the floating body 12 on which the pedestal 11 of this wind power generator is mounted has one or more (four in FIG. 6) tension mooring lines 13 called tendons attached to the floating body 12. And anchored at anchors 14 provided on the bottom 2 of the seabed, lake bottom, riverbed or the like.

  In general, the tension mooring floating body 1X as shown in FIG. 6 is not limited to the wind power generator, and the buoyancy of the floating body 12 is increased by injecting ballast water into the ballast tank of the floating body 12 or by loading the ballast. It moves on the anchor 14 previously installed in the set water area in a state of being submerged smaller than in the installation state. After the movement, the upper end of the tension mooring line 13 is coupled to the upper mooring part 12 c of the floating body 12, and the lower end of the tension mooring line 13 is coupled to the lower mooring part 14 c of the anchor 14.

  After the coupling, the buoyancy of the floating body 12 is set to a preset buoyancy by discharging the ballast water or removing the ballast while paying attention to the inclination of the floating body 12 on which the upper structure 11 is mounted. Further, the length of the tension mooring lines 13 is changed to adjust the inclination of the upper structure 11 and the magnitude of the tension of each tension mooring line 13. In this installation, the tension mooring line 13 is set in advance so that the tension mooring floating body 1X does not shake up and down, laterally tilt, and vertically tilt in the waves, and the movable range within the horizontal direction falls within the allowable range. The initial tension is applied and moored (for example, see Patent Documents 1 and 2).

  Further, in the case of mounting a wind power generator that does not require a large area for mounting the superstructure, a columnar body (center column) 12a penetrating the water surface as shown in FIG. The upper end side of a plurality of tension mooring lines 13 is fixed to a floating body 12 having a submerged buoyancy body (pontoon) 12b connected to the lower part of 12a, and the lower end side of the tension mooring lines 13 is installed on the bottom 2 14 is connected to the lower mooring portion 14c, and tension is applied to the tension mooring line 13 to hold the tension mooring floating body 1Y in position (see, for example, Patent Documents 3 and 4).

  In a tension mooring floating body 1Y called a “mini tension leg platform (mini TLP)” composed of a floating body 12 having a columnar body 12a penetrating the water surface and a submerged buoyant body 12b connected to the columnar body 12a, The tension mooring line 13 is moored to the upper mooring part 12c of the submerged buoyancy body 12b at the water depth D. Since the tension mooring floating body 1Y has only the columnar body 12a penetrating the water surface after installation, the influence on the tension of the tension mooring line 13 due to fluctuations in the tide level and up and down of the water surface due to waves is reduced.

  However, when the tension mooring floating body 1Y is not towed or installed when the tension mooring floating body 1Y is installed, since the portion penetrating the water surface is only the columnar body 12a, the static restoring force is remarkably small, and the tension mooring floating body There is a problem that the stability performance is very bad. Therefore, at the time of towing and installation, it is indispensable to use a crane in order to maintain the posture of the tension mooring floating body 1Y.

  In this case, even a “mini TLP” equipped with a wind turbine generator has a weight exceeding 1,000 tons, and the crane to be used must be a large offshore crane. This large offshore crane has a small number of ships in the market and is necessary from the time of towing until the completion of installation, so that the period of use of the large offshore crane becomes long. Therefore, it is difficult to adjust the schedule of towing and installation work, and there is a problem that costs increase.

  Further, in the “mini TLP” of the prior art, the upper mooring portion 12c of the tension mooring line 13 is in the water, so that the work for attaching the tension mooring line 13, the tension adjustment work, the maintenance check work, and the like are the work in the water. For this reason, the workability is poor and the work time is long, so the cost for these work increases. In addition, when the lower mooring part sinks unequally due to an earthquake or the like after installation, it is necessary to adjust the length of the tension mooring line 13 with respect to this unequal subsidence. Since it is submerged, there is a problem that it is necessary to work underwater.

Japanese Patent Laid-Open No. 1-145292 Japanese Patent Laid-Open No. 4-197887 Japanese Utility Model Publication No. 64-2692 JP 2005-69025 A

  The present invention has been made in view of the above situation, and the purpose of the present invention is to increase the static restoring force of the tension mooring floating body during towing and installation of the tension mooring floating body, thereby ensuring stability. Can reduce the capacity and frequency of use of large offshore cranes that are required, and can be made unnecessary depending on the weather and sea conditions of the water area. An object of the present invention is to provide a tension mooring floating body and a towing and installation method of the tension mooring floating body capable of performing the height adjustment work above the water surface.

  The tension mooring floating body for achieving the above-mentioned object is achieved by fixing the upper ends of a plurality of tension mooring lines to a floating body having a columnar body penetrating the water surface and a submerged buoyant body connected to the columnar body. For a mooring floating body that connects the lower end side of the mooring line to a lower mooring part installed on the bottom of the water and holds the position by applying tension to the tensioning mooring line, for mooring having a water surface penetrating buoyancy portion that penetrates the water surface A member is provided connected to the submerged buoyancy body, and the upper end side of the tension mooring line is fixed to an upper mooring portion provided above the water surface of the mooring member.

  According to this configuration, when the tension mooring floating body is not moored, that is, during towing or installation, the mooring floating body is inclined horizontally or vertically by the water surface penetrating buoyancy portion separately from the columnar body (center column). Because of this, it is possible to tow in a stable state with reduced risk of rollover. In addition, a stable state can be maintained even during installation work.

  In other words, by forming the mooring member of the tension mooring line of the submerged buoyancy body with the water surface buoyancy part penetrating the water surface, a restoring force due to the buoyancy of the water surface buoyancy part is newly added, and the tension mooring floating body Restoring power increases. Thereby, even in the state where the tension mooring cable before the completion of installation at the time of towing or installation is not attached, the stability of the tension mooring floating body with respect to the horizontal inclination and the vertical inclination is remarkably improved, and the installation work is facilitated.

  Therefore, the capacity and frequency of use of the large offshore crane required for towing and installation can be reduced, and the large offshore crane can be eliminated depending on the weather and sea conditions of the towed and installed water area. As a result, costs for towing and installation work can be reduced.

  Furthermore, since the upper mooring part for attaching the upper end part of a tension mooring line is provided in the site | part above the water surface of a mooring member, the attachment work and tension | tensile_strength adjustment work of a tension mooring line can be performed above the water surface. It becomes like this. Therefore, since workability is improved as compared with the underwater work in the prior art, the work efficiency of the installation work and the maintenance inspection work can be improved, and the cost can be reduced.

  The columnar buoyancy body is provided so as to penetrate the water surface away from the columnar body (center column), and the greater the separation distance, the larger the moment lever, so that a large restoring force can be obtained with the same water surface area. . However, since there is a limit to increasing the separation distance, it is preferable to connect the end portion of the submerged buoyant body and provide the columnar buoyancy body above the end portion.

  In the above-described tension mooring body, the anchoring member is formed by a columnar buoyancy body having a hollow portion, the upper portion of the tension mooring line is passed through the hollow portion, and the upper end side of the tension mooring line is the columnar buoyancy body. It attaches to the upper mooring part provided in the site | part above the water surface.

  According to this configuration, the columnar buoyancy body (corner column) penetrating the water surface is provided as a mooring member by connecting to the submerged buoyancy body, thereby newly adding a restoring force due to the buoyancy of the water surface portion of the columnar buoyancy body. Restoring power increases. Further, since the upper mooring portion is provided above the water surface of the columnar buoyant body, the attachment work of the tension mooring line and the tension adjustment operation can be performed at a site above the water surface, and workability is improved. In addition, since the tension mooring line is inserted through the hollow portion of the columnar buoyancy body, collision and entanglement between the tension mooring line and the columnar buoyancy body can be avoided.

  In the above-described tension mooring floating body, after the tension mooring floating body is installed, a part or all of the water surface penetration buoyancy portion of the mooring member is provided so as to be removable.

  According to this configuration, it is possible to attach a removable surface-buoyant buoyancy part at the time of towing and installation where static restoring force is required and to make it stable, and this removable after installation that does not require static restoring force. By removing the water surface penetrating buoyancy portion, the water surface area of the mooring member penetrating the water surface after installation can be reduced. As a result, after installation, the water surface area decreases, so the amount of increase or decrease in buoyancy due to water level fluctuations decreases. Therefore, the amount of fluctuation in the tension of the tension mooring line due to tide level changes and waves can be reduced.

  Moreover, since the water surface penetration buoyancy part removed after installation can be used at the time of towing and installation of another tension mooring floating body, this water surface penetration buoyancy part can be used repeatedly. As a result, when a large number of tension moorings are manufactured, towed, and installed, the overall steel weight can be reduced and a significant cost reduction can be achieved.

  In the above-described tension mooring floating body, the mooring member is formed of a frame structure, and when the tension mooring floating body is towed and installed, the water surface penetrating buoyancy portion is attached to the frame structure, After installation, the water surface penetrating portion is removed.

  According to this configuration, since the mooring member is a frame structure, the weight of the steel material can be remarkably reduced, and the force due to the tide level and the waves acting on the mooring member after installation can be remarkably reduced.

  And the towing and installation method of the tension mooring floating body for achieving the above object is the upper end of a plurality of tension mooring lines in the floating body having a columnar body penetrating the water surface and a submerged buoyancy body connected to the columnar body. In the towing and installation method of the tension mooring floating body that fixes the side, connects the lower end side of the tension mooring line to the lower mooring part installed on the bottom of the water, and holds the position by applying tension to the tension mooring line. A mooring member provided in connection with the submerged buoyant body and penetrating the water surface is provided with a water surface penetrating buoyancy part to increase static restoring force during towing and installation work, and the tension mooring cable The upper mooring portion to be attached is provided above the water surface of the mooring member, and the mooring operation on the upper end side of the tension mooring line is performed above the water surface.

  According to this method, when the tension mooring floating body is towed or installed, the water penetration buoyancy part can generate a restoring force against the horizontal or vertical inclination of the tension mooring floating body, so that the risk of overturning is reduced and stable. Can be towed at. It can also be stabilized during installation. Therefore, the frequency of suspension of tension mooring floating bodies by large offshore cranes can be reduced, and depending on weather and sea conditions of towing and installation water areas, suspension by large offshore cranes can be made unnecessary. Installation work is facilitated and cost reduction can be achieved.

  Moreover, since the upper mooring part to the tension mooring floating body of the tension mooring line is provided above the water surface of the mooring member, the tension mooring line can be attached and the tension can be adjusted above the water surface. Therefore, workability is improved as compared with the conventional underwater work, and the cost of installation work and maintenance inspection work can be reduced.

  In the towing and installation method of the tension mooring floating body described above, the water surface penetrating buoyancy portion is removed after the tension mooring floating body is installed. According to this method, the water surface through buoyancy portion removed after installation can be used when towing and installing another tension mooring floating body, and the water surface through buoyancy portion can be used repeatedly. Therefore, when many tension mooring floating bodies are manufactured, towed, and installed, the steel material weight as a whole can be reduced, and a significant cost reduction can be achieved.

  Further, in the above-described towing and installation method of the tension mooring floating body and the tension mooring floating body, when the tension mooring floating body is equipped with a wind power generator, the wind power generation apparatus has an action point of wind power at the time of towing and installation. Since it becomes extremely high from the surface of the water, it is easy to tip over, and there is a high risk of tipping over due to the inclination, so the effect of the present invention is further increased.

  According to the towing and installation method of the tension mooring floating body and the tension mooring floating body according to the present invention, when the tension mooring floating body is towed or installed, a restoring force against the horizontal inclination and the vertical inclination of the tension mooring floating body is generated by the water surface penetrating buoyancy part. As a result, the risk of rollover is reduced, and the tow can be carried out in a stable state, and is also stable during installation. Therefore, the frequency of suspension of tension mooring floating bodies by large offshore cranes can be reduced, and depending on weather and sea conditions in the water area, suspension by large offshore cranes can be made unnecessary, so towing and installation work is easy. Thus, cost reduction can be achieved.

  Moreover, since the upper mooring part which attaches the upper end part of a tension mooring line is provided above the water surface of a mooring member, the attachment work of a tension mooring line and the tension | tensile_strength adjustment work can be performed in the site | part above a water surface. Therefore, workability is improved as compared with the conventional underwater work, and the cost of installation work and maintenance inspection work can be reduced.

  Hereinafter, the towing and installation method of the tension mooring floating body and the tension mooring floating body according to the present invention will be described with reference to the drawings. Here, in particular, a tension mooring floating body in which a wind power generator is mounted on an upper structure supported by the floating body will be described as an example. However, the present invention is not limited to the wind power generator, and the upper structure includes an oil well drilling device, and the like. The present invention can also be applied to a tension mooring floating body equipped with a plant or a measuring device.

  As shown in FIG. 1, a tension mooring floating body (mini tension leg platform) 1 according to a first embodiment of the present invention includes an upper structure 11 on which a wind power generator 10 is mounted, and the upper structure. 11, a floating body 12 for supporting the floating body 12, a plurality of tension mooring lines 13 called tendons for mooring the floating body 12 (two in FIG. 1, three in total at six locations) 13, and the tension mooring lines 13 It comprises an anchor 14 for fixing to the water bottom 2 such as the sea bottom, lake bottom or river bottom.

  The floating body 12 supports the weight of the upper structure 11 with buoyancy and maintains the upper structure 11 at a preset height above the water. The floating body 12 includes a cylindrical body 12a formed of a column or a polygonal column for supporting the upper structure 11, and three or more (3 in FIG. 1) extending radially from the bottom of the cylindrical body 12a. And a submerged buoyancy body (lower buoyancy body) 12b formed of a columnar body. The cylindrical body 12a is called a center column, and the submerged buoyancy body is called a pontoon. The cylindrical body 12a and the submerged buoyancy body 12b have a hollow structure and are configured to generate buoyancy using steel, prestressed concrete (PC), or the like.

  In the present invention, the anchoring member 15 having a water surface penetrating buoyancy portion is connected to the end of the submerged buoyancy body 12b opposite to the cylindrical body 12a. The water surface penetrating buoyancy portion is provided such that a part of the upper portion protrudes above the water surface 3. As shown in FIGS. 1 and 2, the mooring member 15 is formed of a columnar buoyant body having a hollow portion 15h, and the upper portion of the tension mooring cord 13 is passed through the hollow portion 15h so that the upper end portion of the tension mooring cord 13 is passed through. The columnar buoyancy body 15 is fixedly supported by being attached to an upper mooring portion 15c provided at a site above the water surface.

  The mooring member 15 may be formed in a columnar shape or a conical shape without a hollow portion, and may be formed in a columnar shape or a conical shape, and the tension mooring line 13 may be guided outside the mooring member 15 and above the water surface. In this case, however, there is a risk that the tension mooring lines 13 collide with the mooring member 15 and damage each other, a risk that the suspended matter collides with the tension mooring lines 13, and the tension mooring lines 13 may be damaged. There is a risk that the mooring line 13 is entangled with the mooring member 15. Therefore, a configuration in which the hollow portion 15h as shown in FIGS. 1 and 2 is inserted is preferable.

  Since the upper mooring portion 15c is separated from the columnar body 12a in plan view, the moment lever related to the inclination of the upper structure 11 is increased, so that the tension mooring line generated by the overturning moment acting on the floating body 12 and the upper structure 11 is increased. 13 changes in tension.

  According to this configuration, the columnar buoyancy body (corner column) that connects to the submerged buoyancy body 12b and reaches the upper part of the water surface through the water surface is provided as the mooring member 15, so that this columnar buoyancy body ( The restoring force due to the buoyancy of the water surface portion of the mooring member 15 is added, and the static restoring force increases. This improves the stability of the tension mooring floating body 13 with respect to the horizontal inclination and the vertical inclination even during towing or when the tension mooring line 13 before installation is not attached, and makes installation work easier.

  The columnar buoyancy body 15 is provided so as to penetrate the water surface away from the columnar body 12b, and the greater the separation distance, the larger the moment lever, so that a large restoring force can be obtained with the same water surface area. Conversely, a small water surface area is sufficient to obtain the same restoring force. However, since there is a limit in increasing the separation distance, it is preferable to connect the end portion of the submerged buoyancy body 12b and provide the columnar buoyancy body 15 above the end portion.

  When the wind power generator 10 is mounted, the wind power application point is significantly higher from the water surface during towing and installation, so that it is easy to tip over and there is a high risk of tipping over due to the inclination. The effect of increasing is important.

  Further, since the upper mooring portion 15c of the tension mooring line 13 to the tension mooring floating body 12 is provided at a position above the water surface of the columnar buoyancy body 15, the work for attaching the tension mooring line 13 and the tension adjustment work are performed above the water surface. The workability is improved. Accordingly, installation work and inspection / maintenance work are facilitated, and these costs can be reduced.

  The tension mooring line 13 is formed of a steel chain, a cable, a rope, or the like, and has an upper end portion attached to the upper via portion 15c and a lower end portion attached to the lower mooring portion 14c of the template 14. At the time of mooring, the length of the tension mooring line 13 is adjusted so that tension is always applied to the tension mooring line 13 so that the floating body 12 is pulled into the water against the buoyancy of the floating body 12. Configure.

  The template 14 is a weight formed of steel, concrete, or the like, and is used as a gravity anchor that is submerged in the water bottom 2 and fixed by its own weight. In addition, you may use the pile (pile) fixed to the ground of the bottom 2 as an anchor. This template 14 is for mooring the floating body 12 at a preset position via the lower mooring part 14c, the tension mooring line 13 and the upper mooring part 15c, and the lower end of the tension mooring line 13 is on the lower side. It is fixed to the mooring part 14c.

  The size of the tension mooring floating body 1 is, for example, when the power generation amount is assumed to be 2 MW, and the windmill 10a has a rotating diameter of about 80 m when installed at a water depth of about 100 m to 200 m on the continental shelf. The rotational axis 10b of the windmill 10a is about 75m above the water surface 3, the diameter of the cylindrical body 12a of the floating body 12 is about 6m, and the height is about 35m. The diameter of the circle passing through the centers of the three anchors 14 Is about 60 m.

  The towing of the tension mooring floating body 1 is carried out by injecting ballast water or placing the ballast into a state of buoyancy suitable for towing, towing with a tugboat or the like, and on a template 14 previously set in a set water area. Move to. In this towing, the tension mooring floating body 1 has improved stability with respect to lateral inclination and vertical inclination due to the water surface penetrating buoyancy portion. Therefore, the required capacity of the large offshore crane is reduced, or the tension mooring by the large offshore crane is performed. The frequency of suspension of floating bodies can be reduced, and depending on the weather and sea conditions of towing and installation water areas, suspension by large offshore cranes can be eliminated.

  After the tension mooring floating body 1 is moved, the upper end of the tension mooring line 13 is attached to the upper mooring portion 15c of the mooring member 15 by using a small offshore crane, a temporary crane provided on the mooring member 15, and the lower end by underwater work. Is attached to the lower mooring portion 14 c of the template 14. Alternatively, the lower end is previously attached to the lower mooring portion 14c of the template 14, and then the template 14 is sunk. When attaching the upper end of the tension mooring line 13, the upper mooring portion 15c is arranged above the water surface and is not an underwater operation, so the attachment operation can be performed with good work efficiency.

  After attaching the tension mooring line 13, paying attention to the inclination of the superstructure 11 and the floating body 12 on which the upper structure 11 is mounted, the ballast water is poured or drained as necessary, and the buoyancy of the floating body 12 is reduced. The inclination of the upper structure 11 and the tension of each tension mooring line 13 are adjusted by adjusting the length of the tension mooring line 13 in a state of buoyancy set in advance.

  In this installation, the tension mooring floating body 1 is moored by applying a preset initial tension to the tension mooring line 13 so that the tension mooring floating body 1 does not move up and down, laterally tilted, or vertically tilted in the waves. This initial tension is a difference between buoyancy and weight, but the tension of the tension mooring line 13 is set by adjusting the length of the buoyancy and the tension mooring line 13 so that the tension is set in advance. Further, the initial tension is set so that the movable range in the horizontal direction also falls within the allowable range.

  And in this 1st Embodiment, the mooring member 15 is made into the state as it is after mooring. In this state, the restoring force by the water surface penetration buoyancy part of the mooring member 15 is maintained as it is. Therefore, both the restoring force and the tension by the tension mooring line 13 act on the inclination of the floating body 12 on which the upper structure 11 is mounted.

  Next, a second embodiment will be described. As shown in FIGS. 3 to 5, in the tension mooring floating body 1 </ b> A according to the second embodiment, the mooring member 15 is a skeleton structure instead of forming the mooring member 15 with a columnar buoyancy body having a hollow portion 15 h. It forms with the body 15a, and it comprises so that the water surface penetration buoyancy part 15b can be attached and detached to this framework structure 15a.

  As shown in FIG. 3 at the time of towing the tension mooring floating body 1A, and at the time of installation as shown in FIG. 4, a state where the water surface penetrating buoyancy portion 15b is attached to the framework structure 15a, and the tension mooring floating body 1A After installation, as shown in FIG. 5, the water surface penetrating portion 15b is removed. The part that can be removed after the tension mooring floating body 1A is installed may be a part of the water surface penetrating buoyancy part or the whole part.

  According to this configuration, the removable water surface buoyancy portion 15b is attached at the time of towing and installation where static restoring force is required, and is removed after installation where static restoring force is not required. The water surface area of the mooring member 15 penetrating the water surface can be reduced. Thereby, the increase / decrease amount of the buoyancy by the surface area which was generating the restoring force reduces. Therefore, the fluctuation amount of the tension of the tension mooring line 13 due to a change in tide level or a wave can be reduced.

  Further, by using the removed water surface penetrating buoyancy portion 15b when towing and installing another tension mooring float 1A, the water surface penetrating buoyancy portion 15b can be used repeatedly, and a large number of tension mooring floats 1A are manufactured, towed and installed. In this case, the weight of the steel material as a whole can be reduced, and a significant cost reduction can be achieved.

  Furthermore, the steel member weight can be reduced by forming the mooring member 15 with the frame structure 15a. In addition, since it is a framework, the water surface area can be remarkably reduced, and the force due to the tide level and waves acting on the mooring member 15 after installation can be significantly reduced.

  According to the towing and installation method of the tension mooring floating bodies 1 and 1A and the tension mooring floating bodies according to the first and second embodiments described above, the tension mooring floating body 12 is supported by the tension moored floating body 12 and supports facilities such as a wind power generator. In the tension mooring floats 1 and 1A provided with the upper structure 11 serving as a pedestal, when the tension mooring floats 1 and 1A are not moored, that is, during towing and installation, they are provided other than the columnar body (center column) 12a. Further, since the restoring force with respect to the horizontal inclination and the vertical inclination of the mooring floating body 12 can be generated by the water surface penetrating buoyancy portions 15 and 15b, the risk of rollover is reduced and stable towing can be achieved. It is also stable during installation.

  Therefore, during towing and installation, the capacity of the large offshore crane that suspends the tension mooring floating bodies 1 and 1A is reduced, the frequency of suspension of the tension mooring floating bodies by the large offshore crane is reduced, and Depending on the weather and sea conditions in the water area, it is possible to eliminate the need for suspension by a large offshore crane. As a result, towing and installation work are relatively easy, and costs can be reduced.

  In addition, since the upper mooring portion 15c to which the upper end portion of the tension mooring line 13 is attached is provided at a position above the water surface of the mooring member 15, the submarine ground is unevenly subtracted due to an earthquake or the like after installation. The attachment work of the tension mooring line 13 and the tension adjustment work can be performed above the water surface. Therefore, workability is deducted compared to the conventional underwater work, and the cost of installation work and maintenance inspection work can be reduced.

It is a figure showing composition of a tension mooring floating body in a 1st embodiment concerning the present invention. It is a figure which shows the mooring member which has a water surface penetration buoyancy part in 1st Embodiment based on this invention. It is a figure which shows the towing state of the tension mooring floating body in 2nd Embodiment which concerns on this invention. It is a figure which shows the state at the time of installation of the tension mooring floating body in 2nd Embodiment which concerns on this invention. It is a figure which shows the state after installation of the tension mooring floating body in 2nd Embodiment which concerns on this invention. It is a figure which shows the structure of the tension mooring floating body of a prior art. It is a figure which shows the state of the tension mooring floating body called mini TLP of a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 1A, 1X, 1Y Tension mooring floating body 2 Water bottom 3 Water surface 10 Wind power generator 10a Windmill 10b Rotating shaft of windmill 11 Upper structure 12 Floating body 12a Cylindrical body 12b Lower floating body 12c Upper mooring part 13 Tension mooring cable 14 Anchor 14c Below Side mooring part 15 Mooring member (columnar buoyancy body: buoyancy part through water surface)
15a Frame member 15b Water surface penetrating buoyancy part 15c Upper mooring part 15d Water surface shape 15h Hollow part T1-T4 Tension of tension mooring line

Claims (6)

  The upper end side of a plurality of tension mooring lines is fixed to a floating body having a columnar body penetrating the water surface and a submerged buoyant body connected to the columnar body, and the lower end side of the tension mooring lines installed on the bottom of the water In the tension mooring floating body that is connected to the mooring portion and holds the position by applying tension to the tension mooring line, a mooring member having a water surface penetrating buoyancy portion that penetrates the water surface is connected to the submerged buoyancy body, and provided. A tension mooring floating body, wherein an upper end side of the tension mooring line is attached to an upper mooring portion provided above the water surface of the mooring member.   The anchoring member is formed of a columnar buoyancy body having a hollow portion, the upper portion of the tension mooring line is passed through the hollow portion, and the upper end side of the tension mooring line is located above the water surface of the columnar buoyancy body. The tension mooring floating body according to claim 1, wherein the tension mooring floating body is attached to the upper mooring portion provided.   The tension mooring floating body according to claim 1 or 2, wherein a part or all of the water surface penetrating buoyancy portion of the mooring member can be removed after the tension mooring floating body is installed.   The mooring member is formed of a frame structure, and when the tension mooring floating body is towed and installed, the water surface penetrating buoyancy part is attached to the frame structure, and after the tension mooring floating body is installed, the water surface penetrates. 4. The tension mooring float according to claim 3, wherein the portion is removed.   The upper end side of a plurality of tension mooring lines is fixed to a floating body having a columnar body penetrating the water surface and a submerged buoyant body connected to the columnar body, and the lower end side of the tension mooring lines installed on the bottom of the water A mooring member connected to the submerged buoyant body and connected to the submerged buoyant body in a towing and installation method of a tension mooring floating body that is connected to a mooring portion and holds the position by applying tension to the tension mooring line. A buoyancy portion penetrating the water surface to increase static restoring force during towing and installation work, and an upper mooring portion for attaching the tension mooring line is provided above the water surface of the mooring member, A towing and installation method for a tension mooring floating body, wherein the mooring work on the upper end side of the rope is performed above the water surface.   6. The towing and installation method of a tension mooring floating body according to claim 5, wherein the water penetration buoyancy portion is removed after the tension mooring floating body is installed.

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