JPS5924020A - Installation of bottomed type marine structure using used tanker - Google Patents

Abstract

PURPOSE:To prevent the movement of a marine structure toward both vertical horizontal directions by a method in which a structure formed by providing concavity and convexity parts in the left and right directions of the bottom of a used tanker is settled on the mound having concavity and convexity of the seabed in such a way as to combine the concaved and convexed portions of both mutually. CONSTITUTION:The hull of a used tanker 1 is divided into plural sections in the vertical direction, and the bottom outer skin 5 and the frame 6 between left and right-handed vertical partition walls 4 in plural sections are cut off. The cut sections are lifted up and again welded to the vertical partition walls 4 to form a concavity 7 at the central part in the left and right directions of the bottom. Also, in other plural sections, the bottom outer skind 5 on the outside of the left and right-handed vertical partition walls 4, the lower part of the side outer skin 11, and the frame 6 are cut off, the lower part of the remaining side outer skin 11 is removed, and the cut sections are lifted up and again welded to the vertical partition walls and the side outer skin 11 to form a convexity 12. The tanker 1 is sunk into water, the concavity 7 and convxity 12 of the tanker bottom are fitted with the convexity 15 and concavity 16 of the mound, and sand 17, etc., is packed into the combined part through a pipe 10.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for installing a bottom-mounted marine structure using a used tanker.

When using a used tanker to construct a bottom-mounted marine structure such as a breakwater, a mound is created on the seabed using rubble, etc., the tanker is floated on the sea surface and towed above the mound, and water is poured into the interior of the mound. The tanker is submerged on a mound, and instead of water, solid heavy materials such as concrete and earth are filled inside and installed on the mound, preventing horizontal movement of the tanker due to waves etc. by the frictional force between the tanker and the mound. . In order to increase the frictional force between the tanker and the mound to reliably prevent horizontal movement of the tanker, it is necessary to increase the coefficient of friction between them, or to increase the friction between the tanker and the solid heavy objects packed inside it. It is necessary to increase the total weight of However, in the case of a tanker, since the hull is made of steel, the coefficient of friction between it and the mound is smaller than that of a concrete caisson, and the total weight, which is equivalent to a concrete caisson, is about 50% higher than that of a concrete caisson. It is necessary and uneconomical.

This invention was made in view of the above-mentioned circumstances, and it is possible to improve the horizontal movement of a used tanker by increasing its resistance to waves, etc., without particularly increasing the total weight of the used tanker and solid heavy objects. The purpose of the present invention is to provide a method for installing a bottom-mounted marine structure using a used tanker, which can reliably prevent the above.

In the method according to the present invention, when installing a used tanker as a submerged marine structure on a mound on the seabed, the hull of the used tanker is divided into a plurality of sections in the longitudinal direction, and the above-mentioned In the compartment, the bottom skin plate between the left and right vertical bulkheads and the aggregate attached to this skin plate are separated from the ship's hull, and then the parts that were separated from the hull are lifted and reattached to the vertical bulkheads, so that the center part of the ship's bottom in the left-right direction is At the same time, in several other sections, the bottom shell plating outside the left and right vertical bulkheads, the lower part of the side shell plating, and the bones attached to these shell plating were separated from the hull, and the lower part of the remaining side shell plating was separated from the hull. After cutting and removing, the parts that were previously separated from the hull are lifted and reattached to the vertical bulkhead and side shell plating to form a protrusion in the center of the ship's bottom in the lateral direction. The mound of this used tanker should be made so that it has an uneven surface when viewed from the bottom, and that the upper surface of the mound on the seabed has an unevenness that corresponds to the unevenness of the ship's bottom. It is characterized by filling the space between the bottom of the ship and the mound at these fitting parts with sand or the like.

According to this invention, the irregularities on the bottom of the ship and the corresponding irregularities on the mound are fitted together, and sand or the like is filled between the hull and the mound at these fitting parts, so that the tanker and the solids packed inside it are Even if the total weight of the tanker is not particularly large, the resistance against waves and the like is increased, and horizontal movement of the tanker can be reliably prevented.

Furthermore, since the bottom of the ship is uneven when viewed in either the longitudinal or lateral direction, it is possible to reliably prevent the tanker from moving in both the longitudinal direction (length direction) and the lateral direction (width direction).

The present invention will be described in detail below with reference to the drawings.

First, as shown in Figure 1, a used tanker (1) to be used as a bottom-mounted offshore structure is pulled into the dock (2), and as shown in Figures 2 to 5. The bottom of the ship will be modified so that it has unevenness when viewed from both the vertical and horizontal directions. That is, first, the hull of the tanker (1) is divided into a plurality of sections in the longitudinal direction with the transverse bulkhead (3) as a boundary. In some every other compartment, the bottom skin (5) between the left and right longitudinal bulkheads (4) and this skin (
5) Cut both left and right ends of the aggregate (6) containing the large bones and small bones attached to it and separate it from the hull. Next, the part separated from the hull is lifted up with jacks (as shown) and welded to the longitudinal bulkhead (4) again, as shown in Figure 4, so that four parts are attached to the center of the bottom of the ship in the left and right direction. (7) is formed. In addition, a plurality of vertical pipes (10) extending from the upper deck (9) immediately inside the longitudinal bulkhead (4) to the fourth section (71) are appropriately arranged in the central tank (8) of the tanker (1). In addition, in several other compartments sandwiched between the four parts (7), the bottom skin (5) outside the left and right longitudinal bulkheads (4), the lower part of the side skin (11), and the outside of these Board (5
i (Aggregate including large bones and small bones attached to Ill (6)
Cut both ends and separate it from the hull. After cutting and removing the lower part of the remaining side shell plating (11), the part that was previously separated from the hull was lifted up with jacks, and the vertical bulkhead (4) and the ship side plating were removed again as shown in Figure 5. Outer panel (
11), thereby forming a convex portion (12) in the center of the ship's bottom in the left-right direction. Also, inside the side tank 03) of the tanker (1), the upper deck (9
) to the bottom shell plate (5) are arranged as appropriate.

On the other hand, a mound (141) is created using rubble on the seabed where the used tanker will be installed, and its top surface is made to correspond to the unevenness of the ship's bottom.Then, the tanker (1) modified as described above is taken out to sea. After towing the tanker (1) to above mound 04), water is poured into the tanker (1) so that the unevenness on the bottom of the ship and the corresponding unevenness on the mound fit together.
sink on mound Q41. Next, solid heavy objects such as earth and sand are poured into the hull, and the tanker (1) is installed at a predetermined position on Mound 0. And finally,
As shown in Figures 6 and 7, mound 0
4) convex part (]5) and the four parts of the bottom of the ship where it fits (
Sand 0η etc. is filled through the pipe (10) between the convex part t12) on the bottom of the ship and the peripheral wall of the four parts (]ω of the mound [+4+] into which this is fitted, and the tanker (1 ) installation is completed.

The arrangement of the irregularities on the bottom of the ship is arbitrary; for example, as shown in Figure 8, the longitudinal section of the ship is divided into two groups, front and back, and in one group, the same four parts (7) as described above are formed on the bottom of the ship. At the same time, a convex portion (12) similar to that described above may be formed on the bottom of the boat in the other group. In this way, the corresponding shape of the upper surface of the mound becomes simple.

[Brief explanation of the drawing]

FIGS. 1 to 7 show an embodiment of the present invention in the order of steps,
Figure 1 is a cross-sectional view showing a used tanker before modification at a dock, Figure 2 is a longitudinal cross-sectional view showing a used tanker after modification at a dock, and Figure 3 is a view taken along the line ■-TfI in Figure 2. , Figures 4 and 5 are line IV-IV and V in Figure 2.
6 and 7 are cross-sectional views showing different cross sections of a used tanker installed on a mound, and FIG. 8 is a 3rd view showing another embodiment of the present invention. This is quite a drawing. (1)...Used tanker, (2)...Dock, (4
)...Longitudinal bulkhead, (5)...Bottom shell plate, (6)...
Aggregate, (7)...Four parts of the ship's bottom, fl]l...Ship side shell, (12)...Bottom protrusion, 04)e...Mound,
(15) @...Mound convex part, 061...Mound concave part, (17)...Sand. Other 4 people Figure 1 Figure 4 Figure 5 Figure 6 Figure 7 and Figure 8

Claims (1)

[Claims] When installing a used tanker as a submerged bottom-mounted marine structure on a mound on the seabed, the hull of the used tanker is divided into multiple sections in the longitudinal direction, and the left and right vertical sections are divided into several sections in advance in the dock. After separating the bottom shell plate between the bulkheads and the aggregate of this shell plate (q) from the hull, lift the part separated from the hull and attach it to the longitudinal bulkhead again to form four parts at the center of the bottom in the left-right direction. With,
In several other sections, the bottom skin on the outside of the left and right vertical bulkheads, the lower part of the side skin, and the aggregate of these skin materials were separated from the hull, and the lower part of the remaining side skin was cut and removed. By lifting the part that was previously separated from the hull and reattaching it to the vertical bulkhead and the ship's side skin, a convex part is formed in the center of the ship's bottom in the left-right direction, so that the bottom of the ship has unevenness when viewed from both the vertical and horizontal directions. Then, the used tanker is sunk onto the mound so that the unevenness of the bottom of the ship and the corresponding unevenness of the mound fit together. A method for installing a bottom-mounted offshore structure using a used tanker, which is characterized by filling the space between the hull and the mound at the mating part with sand or the like.