JPH0459412B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an underwater girder bottom-mounted rubble leveling device, and in particular, an underwater girder that can be accurately installed on the water bottom with relatively simple operation. This invention relates to an underwater girder bottom-mounted rubble leveling device.

[Prior art] For example, in order to construct a foundation structure on the seabed, first the seabed sediment is dredged, a layer of rubble such as gravel or crushed stone is sequentially formed to a predetermined thickness on the bottom of the dredged material, and then a structure is built on top of the dredged sediment. Build. In this manner, the top surface of the rubble layer must be leveled to make it substantially flat, and for this purpose, a process of introducing rubble and a screed process for leveling the layer are required.

There are two types of equipment for loading and leveling the rubble: one is a ladder suspended from a work boat to load and level the rubble, and the other is an underwater girder installed on the seabed for loading and leveling the rubble. There are known forms that perform this.

The present invention belongs to the latter type, and this type of device is preferable because it can stably load and level rubble without being affected by waves, but the conventional device uses underwater girders. There was a problem with installing it on the seabed. In other words, (i) In the case of conventional equipment, the underwater girders and sinkers are separate, and the four sinkers are first placed individually at a depth of 40 m.
Since it is installed on a rubble mound surface with uneven front and back, errors occur in installation distance, angle, and level.

(ii) Construction and surveying to absorb the above errors will require a great deal of time and expense. Also, a large amount of space and a large amount of space are required to absorb errors.

(iii) If there is a height difference (slope) on the rubble mound surface, the sinker will land on the bottom at a slope, making it difficult to adjust the level of the underwater girder.

(iv) If there is an error in distance or angle, an error will occur in the four legs of the underwater girder, and unreasonable force will be applied to the underwater girder, causing the screed machine to stop working.

(v) Since the sinker is large, it takes time and money to remove and move it.

[Object of the Invention] The present invention has been made to solve the above-mentioned drawbacks of conventional rubble leveling devices, and its purpose is to provide a rubble leveling device that can easily and accurately install underwater girders. In addition, even if there is a height difference (slope) on the rubble mound surface and the sinker lands on the bottom along the slope, no undue force is applied to the underwater girder, and the level of the underwater girder can be easily adjusted. To provide a rubble leveling device which can use a relatively small sinker as a sinker, and which allows the sinker to be easily removed and moved.

[Structure of the Invention] Therefore, according to the present invention, a hydraulic jack that extends and retracts in the vertical direction is provided at each corner of an underwater girder assembled in a rectangular shape that supports a screed machine and guides the movement of the machine. A sinker having a concave portion is suspended from the lower end of the jack up leg by a chain, and a horizontal reaction force device is attached via a spherical bearing to the lower end of the hydraulic jack of the jack up leg, and the horizontal reaction force is The device is equipped with a hydraulic jack that touches the bottom wall of the recess of the sinker and expands and contracts in the left and right directions, and by extending the hydraulic jack, the hydraulic jack applies pressure to the side wall of the recess of the sinker and causes a horizontal reaction. Provided is an underwater girder bottom-mounted rubble leveling device that prevents slippage between the power device and the power device.

When implementing the present invention, a structure is adopted in which a float is provided on the underwater girder and the underwater girder is pulled under the work boat (barge) to integrate the barge and the underwater girder.

[Operations and Effects of the Invention] As described above, in the rubble leveling device according to the present invention, the underwater girder and the sinker are integrated, so when the underwater girder is sunk, the sinker is also sunk at the same time, so that it can be used in large depths of water. The legs of the underwater girder and the sinker do not shift in position even when the girder is in the water, the effort required to install the underwater girder is reduced, and the installation can be carried out with high accuracy, and the sinker may be small.
Its removal and movement become easier. In addition, the horizontal reaction force device is connected to the jack up leg with a spherical bearing, so it can rotate freely, allowing the underwater girder to land on the bottom along the slope of the sinker, and preventing excessive force from being applied to the underwater girder. Therefore, inconveniences such as the screed machine not operating are eliminated. In addition, the legs of the underwater girder are jack-up legs equipped with hydraulic jacks, so the installation height of the underwater girder can be adjusted to the unevenness of the rubble mound surface, and the underwater girder can be installed with high precision. can.

[Examples] Examples of the present invention will be described below with reference to the drawings.

In FIGS. 1 to 3, the work boat is designated as a whole by 1, and this work boat 1 includes a steering winch 2, an underwater girder lifting winch 3, a crushed stone storage hopper 4, a conveyor 5, and a screed machine 11 to be described later. A crushed stone hopper 6 and the like for dropping crushed stone into the tremie pipe 12 are provided. The whole number 7 indicates an underwater girder assembled into a rectangular shape, and a sheave 8,
It is suspended and submerged via a wire 9. A float 10 is provided on the underwater girder 7 to increase buoyancy. Reference numeral 11 denotes a screed machine, to which the crushed stone conveyed from the crushed stone storage hopper 4 to the crushed stone hopper 6 by the conveyor 5 is supplied via a tremie pipe 12.
Drop crushed stones and level the crushed stones. Therefore, the screed machine 11 is supported by the underwater girder 7 and moves horizontally along the underwater girder 7.

Further explanation will be given with reference to FIGS. 4 to 6 in addition to FIGS. 1 to 3. A jack up leg 13 is fixedly provided at each corner of the underwater girder 7. It is equipped with a hydraulic jack 14 that expands and contracts in the vertical direction. Further, a float 15 is provided at the tip of the jack up leg 13. A sinker 16 is suspended from the lower end of each jack up leg 13 by a chain 17, and this sinker 16 has a recess (groove) 18.
is formed. Further, a horizontal reaction force device generally designated 20 is attached to the lower end of the hydraulic jack 14 of the jack up leg 13 via a spherical bearing 19. The horizontal reaction device 20 applies pressure to the side wall 18b of the recess 18 of the sinker 16 to prevent the sinker 16 and the horizontal reaction device 20 from slipping.

Next, referring mainly to FIGS. 4 to 6, the manner in which the underwater girder is installed on the seabed surface will be explained.

As mentioned above, the jack up leg 13 is attached to the underwater girder 7.
The sinker 16 is suspended from the jack up leg 13 by a chain 17. The underwater girder 7 is lowered by the underwater girder lifting winch 3 on the work boat 1 via a sheave 8 and a wire 9.

The underwater girder lifting winches 3 (4 units) operate in equal succession, and by lowering the winches 3, the four suspension points of the underwater girder 7 descend at a constant and gentle speed (the 4th
figure).

As the underwater girder 7 descends, the sinker 16 also descends. The sinker 16 hits the highest point of the rubble mound surface A and lands on the bottom. At this time, rubble mound surface A
If there is a difference in height (gradient), the object will land on the bottom along this difference in height.

Furthermore, the underwater girder 7 descends, and the jack up leg 1
The horizontal reaction force device 20 installed at the base of 3 is the sinker 1
It bottoms out on the bottom wall 18a of the recess 18 of No.6.

The horizontal reaction force device 20 is connected to the recessed bottom wall 1 of the sinker 16.
When the underwater girder 8a reaches the bottom, the lowering of the underwater girder lifting winch 3 is stopped and the brake is applied to the winch 3 to support the underwater girder 7.

Next, the hydraulic jack 21 built into the horizontal reaction device 20 is extended to apply pressure to the side wall 18a of the recess 18 of the sinker 16 to prevent the sinker 16 and the horizontal reaction device 20 from slipping.

At this time, since the horizontal reaction force device 20 is connected to the jack up leg 13 by a spherical bearing 19, it can rotate freely and can land on the bottom along the slope of the sinker 16 (FIG. 5).

Next, in order to cause the horizontal reaction force device 20 to bottom out on the bottom wall 18a of the recess of the sinker 16 that has bottomed out at a low place on the rubble mound surface A, the hydraulic jack 14 built in the jack up leg 13 is extended. When the horizontal reaction device 20 touches the bottom wall 18a of the recess of the sinker 16, the hydraulic jack 21 of the horizontal reaction device 20 is extended to apply pressure to the side wall 18b of the recess of the sinker 16, causing the sinker 16 and the horizontal reaction device 20 to Avoid slipping.

In this way, 4 points are jacked up leg 1 in sequence.
3 and the horizontal reaction force device 20 are operated to install the underwater girder 7 and adjust the level.

Finally, the levels of the four underwater girders 7 are measured using a transponder or the like, and the level of the underwater girders 7 is finely adjusted using the hydraulic jacks 14 of the jack up legs 13.

In addition, the hydraulic jack 1 of the jack up leg 13
4 is provided with a locking device to prevent it from falling even when the load is applied.

[Conclusion] As explained above, according to the present invention, underwater girders can be installed easily and accurately, and a rubble layer for constructing foundation structures on the seabed or underwater can be efficiently constructed. It is something.

[Brief explanation of drawings]

Figures 1 to 3 show the overall appearance of an underwater girder type rubble leveling device according to an embodiment of the present invention, in which Figure 1 is a front view, Figure 2 is a plan view, Figure 3 is a side view, Fourth
Figures 5 and 6 are front views showing the installation process of the underwater girder. 1... Work boat, 2... Ship operation winch, 3... Underwater girder lifting winch, 4... Crushed stone storage hopper, 5
... Conveyor, 6 ... Crushed stone hopper, 7 ... Underwater girder, 8 ... Sheave, 9 ... Wire, 10 ... Float, 11 ... Screed machine, 12 ... Tremy pipe, 13 ... Jacket leg, 14 ……
Hydraulic jack, 15...Float, 16...Sinker, 17...Chain, 18...Recess, 19...
...Spherical bearing, 20...Horizontal reaction force device, 21...Hydraulic jack.

Claims (1)

[Claims] 1. A jack up leg equipped with a hydraulic jack that expands and contracts in the vertical direction is fixedly provided at each corner of an underwater girder assembled in a rectangular shape that supports a screed machine and guides the movement of the machine, and the lower end of the jack up leg is provided. A sinker with a concave portion is suspended from the sinker by a chain, and a horizontal reaction device is attached to the lower end of the hydraulic jack of the jack up leg via a spherical bearing, and the horizontal reaction device bottoms out on the bottom wall of the concave portion of the sinker. At the same time, it is equipped with a hydraulic jack that expands and contracts in the left-right direction, and by extending the hydraulic jack, the horizontal reaction force device prevents the sinker, which applies pressure to the side wall of the sinker recess, from slipping. An underwater girder bottom rubble leveling device characterized by: