JPH0558960B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to improvements in mooring methods and devices for retractable mooring type super buoys installed in waters with sandy bottoms and wavy lines and strong water currents.

(b) Conventional technology The mooring of a retractable mooring type spar buoy to the bottom of the water is as follows:
In order to overcome the resistance of waves and water currents and maintain a fixed position, the sinkers used for mooring are usually concrete blocks that have a weight in the water that is about twice the buoyancy of the buoy minus its own weight.

(c) Problems to be solved by the invention In areas where the underwater geology at the target point is sandy and there are strong waves and water currents, the area around the sinker may be scoured by the water current, causing the sinker to sink or tilt. Buoy marker lights may not be able to maintain the specified height. In this case, it will be necessary to reposition the ship using a crane ship, and even if the ship is repositioned, there is a risk that the ship will sink again. Subsidence due to scouring may occur, especially if the vessel is installed in a sea area with sand drift or in a wave-breaking zone.

The present invention provides a mooring method and device for a retractable mooring type spar buoy that is stable and does not cause sinking even when set up in such sea areas.

(d) Means for solving the problem The present invention consists of driving a pile into the water bottom, having a mooring ring on the top surface of the foundation pile with the pile head protruding from the water bottom. This is a mooring method and apparatus for a retractable mooring type spar buoy, in which a sinker with a slightly larger underwater weight is mounted and fixed, and the lower end of the marker column is moored to the mooring ring with a mooring tool.

(E) Effect Because of the structure described above, a small amount of its own weight and external forces from waves, water currents, etc. used on the buoy act on the pile, but the mooring of the buoy is a flexible mooring and no bending moment is applied. Therefore, the sinking weight is sufficiently supported by the gripping force of the piles driven into the ground, and since the sinking weight is placed and fixed on the piles that protrude from the water bottom, there is a gap between the sinking weight and the water bottom, and the sinking weight cannot be directly connected to the sinking sink. This avoids scouring caused by the water flow hitting the surface. Furthermore, even if there is some scouring caused by the water flow hitting the exposed part of the pile, the gripping force of the pile is hardly affected, the sinking weight can be stably held in a fixed position, and there is no fear of sinking.

(f) Examples Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is an overall view including a mooring device of a retractable mooring type spar buoy (in this example, an observation buoy) embodying the present invention, where 1 is a retractable mooring type spar buoy and 2 is a mooring device. 3 is a buoyancy body, 4 is a marker column body, 5 is a mooring ring for buoy mooring attached to the lower end of the marker column body, 6 is a mooring ring for buoy mooring attached to the upper surface of sinker 7,
The sinking weight 7 is a sinking weight placed and fixed on the head of a foundation pile 8 driven into the seabed 10. The head of the pile 8 protrudes from the water bottom, and the lower surface of the sinking weight 7 has a predetermined gap between it and the water bottom. However, the water flow that hits the sinker can pass through the gap,
This prevents scouring caused by the vortex generated when the water current hits the sinker.

The underwater weight of this sinker 7 is slightly larger than the buoyancy of the buoy after subtracting the buoy's own weight, and the sinker 7, which is connected to the buoy with a mooring device 9, is lowered onto the pile 8 while being suspended with the buoy by a crane boat. A weight 7 is placed thereon to facilitate underwater fixing work between a fixture 11 attached to the sinking weight and the pile head. If sinking weight 7 is omitted, it is possible to pull the buoy's mooring ring directly onto the pile 8 using a mooring device and moor it, but in this case, the large buoyant force of the buoy will act directly on the pile 8 as a pull-out force. Attachment and detachment of shaft pins or bolts for attaching and detaching from piles becomes an extremely difficult task. Also, by providing this sinker 7, only a small amount of gravity is applied to the pile 8,
The pile 8 only needs to have a holding force sufficient to hold back the external force applied to the buoy due to wind and waves, and may be much smaller than the foundation pile when the aforementioned sinking weight is omitted.

Figures 2 a and b are a side view and a plan view of the head of the pile 8 and sinker 7, Figure 3 a is a detailed side view of the vicinity of the fixture 11, Figure 3 b is a plan view thereof, Figure 3 c is Figure 3a
Figure 3d is a plan view of the top surface of the pile in A-A view.
It is a BB perspective view of FIG.

In this example, three foundation piles made of steel pipes are used and are driven into the water bottom with their heads left intact.

In order to reduce resistance to water flow, the sinking weight 7 is made of a flat concrete block and has a hexagonal planar shape, with a fixture 11 protruding from the side.

The fixing device 11 includes a horizontal flat plate 11' that is connected to a flange 8' attached to the top surface of the pile 8 by bolts and nuts;
It consists of a vertical plate 11'' attached to the side of the sinking weight, and a bracket 11 that connects and reinforces both plates.
Furthermore, a guide 12 that fits into the pile head is provided on the lower surface of the flat plate 11' to facilitate positioning.

In addition to the main mooring device 9, the mooring device in this example includes a reinforcing mooring device 9' that prevents the mooring device from flowing out when the main mooring device breaks.

Although three stakes were used in this example, two stakes may be used as shown in Figure 4, or if the buoy is small, one stake may be used as shown in Figure 5. Good too.

(g) Effects of the invention With the above configuration, even if the site is located in an area where the geology of the water bottom is sandy and scouring is likely to occur,
Since the sinking weight is supported on foundation piles with a distance from the water bottom, the eddies of the water that hit the sinking weight do not reach the water bottom, and even if there is scouring caused by the vortex of the water that hits the pile, it will not reach the ground. There is almost no effect on the holding power of the driven piles, and there is no fear that the sinker will sink or tilt. In addition, since the underwater weight of the sinker is slightly larger than the buoyancy of the buoy after subtracting the buoy's own weight, the weight of the sinker that hangs on the pile is small, and the weight of each sinker is small for periodic inspection and maintenance. It can be easily installed and removed, and the weight of the sinking weight is half that of a sinking weight alone, so the crane ship needed for construction work or lifting for inspection can be small. Furthermore, the present invention provides a stable mooring method and device for a retractable mooring type spar buoy, which causes less pollution of the sea area during construction, has a shorter construction period, and is more economical than the dredging and rubble construction method.

[Brief explanation of the drawing]

Figure 1 is an overall view of the retractable mooring type spar buoy that implements the present invention, including the mooring device, Figure 2 a, b
are side and plan views of the pile head and sinker, Fig. 3a is a detailed side view of the vicinity of the fixing device, Fig. 3b is its plan view, and Fig. 3c is A-A in Fig. 3a. 3d is a plan view of the top surface of the pile, and FIG. 3d is a BB view of FIG. 3b. FIGS. 4a and 4b and 5a and 5b are drawings showing a side view and a plan view, respectively, of a mooring device in which there are two foundation piles and one foundation pile according to the present invention. 1...Retractable mooring type spar buoy, 2...Mooring device, 3...Floating body, 5, 6...Mooring ring, 7...
Sinking weight, 8...Pile, 9...Mooring device, 11...Fixing device.

Claims (1)

[Scope of Claims] 1. A buoyant body is provided in the middle of the marker body, and the lower end of the marker body is moored to a sinker so that the buoyant body is drawn into the water and the water line is located in the middle of the marker body above the buoyant body. west,
In the mooring method of a retractable mooring type super buoy that stands upright in the water due to buoyancy, it has a mooring ring on the top surface on a foundation pile that is driven into the water bottom and the pile head protrudes from the water bottom to a specified height, and the buoy's own weight is subtracted. A sinker whose underwater weight is slightly larger than the buoyancy of the buoy is fixed by placing a fixing device on the pile head that has a guide material that fits into the pile head provided on the bottom or side of the sinker, and A method for mooring a retractable mooring type super buoy, characterized in that the lower end of the marker is moored to the ring using a mooring tool, and a predetermined distance is maintained between the sinker and the water bottom. 2. A buoyant body is provided in the middle of the marker body, the lower end of the marker body is moored to a sinker, the buoyant body is drawn into the water, and the water line is placed halfway up the marker body above the buoyant body;
A mooring device for a retractable spar buoy that stands upright in the water due to buoyancy consists of a foundation pile that is driven into the water bottom and whose pile head protrudes from the water bottom to a predetermined height, and a mooring ring that is placed on top of the pile. A sinker with an underwater weight slightly larger than the buoyant force of the buoy minus its own weight, placed on the pile head at a predetermined distance from the water bottom, and a sinker installed on the bottom or side of the sinker and inside the pile head. A mooring device for a retractable mooring type spar buoy, characterized in that the mooring device comprises a fixing device for a sinker and a pile having a guide that fits into the mooring ring, and the lower end of the marker column is moored to the mooring ring by the mooring device.