JP2589628B2 - Installation method of caisson by work boat - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a caisson installation method using a work boat.

[0002]

2. Description of the Related Art Caisson installation on the sea
Conventionally, there is the following method.

[0003] 1) A method of installing a caisson by mounting an installation facility such as a winch directly on the caisson.

2) A method of installing a caisson using a barge equipped with installation equipment.

3) A method of installing a caisson by a hoist ship.

In both of the above methods 1) and 2), the right and left sway may become large just before the caisson's landing, but there is a large possibility that sufficient measures cannot be taken. If the construction method is selected from the above, the method of 3) using a hoist ship is relatively suitable.

In the method using the hoist ship, the caisson is held at a predetermined position by the steering winch of the hoist ship, and a ballast necessary for stability after landing on the caisson is injected into the caisson with a predetermined bottom clearance secured. The crane lowers the caisson so that the bottom of the caisson can be minimized. Can be prevented from moving.

[0008]

However, the conventional hoist ship system has the following problems.

1) The hoist ship is also a floating body, and it is difficult to control the floating body with the floating body.

[0010] 2) It takes time to anchor and hoist the hoist ship.

3) There is a lot of manual labor at sea, which is dangerous.

4) Since it is governed by the weather resistance of the anchor ship, the weather resistance is reduced.

The present invention has been made to eliminate the above disadvantages.

[0014]

SUMMARY OF THE INVENTION A method of installing a caisson by a work boat according to the present invention is a step of positioning a caisson-installed hoist ship comprising a catamaran, and at least a part of a newly installed caisson is a catamaran of the hoist ship. A process of drawing water into the space, a process of pouring water into the newly-constructed caisson, and a process of allowing a surplus water depth of about 1 m. And a step of operating the hoist ship to lower the new caisson and land it.

In the method for installing a caisson by a working boat according to the present invention, the step of positioning the hoist ship includes the step of drawing an existing caisson between the catamaran and the step of pouring water into the hoist ship and placing it on the existing caisson. And a step of seating.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

In the present invention, as shown in FIG. 1, a caisson-installed hoist ship 1 comprising a catamaran is towed to the existing caisson 2 side, and as shown in FIGS.
Is drawn into between the catamaran and water is injected into the hoist ship 1 as shown in FIG. 4 and is seated on the existing caisson 2.

Next, as shown in FIG. 5, the new caisson 3 is towed to the hoist ship 1 side, and at least a part of the new caisson is pulled into the catamaran on the bow side of the hoist ship 1 as shown in FIG. 8, a lifting wire 4 is attached to the new caisson 3, and as shown in FIG. 8, water is poured into the new caisson 3 until the surplus water depth becomes about 1 m. 4 is tensioned, and a water ballast necessary for landing is poured into the newly-installed caisson 3 with a sufficient depth of 1 m secured.

At this time, preferably, the bow ballast in the hoist ship 1 is drained to reduce the weight applied to the hoist ship 1,
The burden on the existing caisson 2 is reduced.

Next, the hoist ship 1 is operated to lower the new caisson 3 as shown in FIG.

Reference numeral 6 denotes a tugboat, and 7 is formed on the inner side of the bow and stern of the catamaran forming the hoist ship 1 in order to equalize the reaction force applied to the hoist ship 1 by the inclination of the new caisson 3. A constant-reaction-type fender 8 is a pneumatic fender provided on the bow side of a connecting portion 9 for connecting the upper part of the catamaran to absorb a surge generated between the newly constructed caisson 3 and the hoist ship 1. By evacuating the air just before the new caisson 3 arrives at the bottom, the interval between the existing caisson 2 and the new caisson 3 can be set to a desired value as shown in FIG.

In the above-mentioned embodiment, the existing caisson 2 is used to fix the hoist ship 1. When there is no such existing caisson 2, the caisson installation hoist ship 1 is fixed to a predetermined position by an anchor. After that, the steps shown in FIGS. 5 to 9 are performed.

[0023]

As described above, the method of installing a caisson using a work boat according to the present invention makes it possible to install the caisson very easily and reliably in a short time even in the case of high waves. The caisson's left and right sway and back and forth sway, which increases when the bottom clearance decreases, are prevented by the catamaran that holds the caisson, and there is a great advantage that the position of the caisson does not greatly shift just before landing.

[Brief description of the drawings]

FIG. 1 is a plan view for explaining a method of the present invention.

FIG. 2 is a plan view for explaining the method of the present invention.

FIG. 3 is a front view for explaining the method of the present invention.

FIG. 4 is a front view for explaining the method of the present invention.

FIG. 5 is a plan view for explaining the method of the present invention.

FIG. 6 is a plan view for explaining the method of the present invention.

FIG. 7 is a side view for explaining the method of the present invention.

FIG. 8 is a side view for explaining the method of the present invention.

FIG. 9 is a side view for explaining the method of the present invention.

FIG. 10 is a plan view of a catamaran portion of a hoist ship used to carry out the method of the present invention.

FIG. 11 is a plan view of a hoist ship used to carry out the method of the present invention.

FIG. 12 is a rear view of a hoist ship used to carry out the method of the present invention.

FIG. 13 is a front view of a hoist ship used to carry out the method of the present invention.

FIG. 14 is a side view of a hoist ship used to carry out the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hoist ship 2 Existing caisson 3 New caisson 4 Lifting wire 5 Crane 6 Tugboat 7 Constant reaction type fender 8 Pneumatic fender 9 Connecting part

Claims (2)

(57) [Claims] 1. A step of positioning a caisson-installed hoist ship comprising a catamaran, a step of drawing at least a part of a newly-installed caisson between the catamaran of the hoist ship, and pouring water into the newly-installed caisson. A step of lowering the water depth to about 1 m, a step of suspending the newly constructed caisson by the above-mentioned hoisting vessel while injecting a necessary water ballast into the newly constructed caisson, and a step of operating the above-mentioned hoisting vessel to operate the above-mentioned hoisting vessel. A caisson installation method using a work boat, comprising a step of lowering and landing a caisson. 2. The method according to claim 1, wherein the step of positioning the hoist ship includes the step of drawing an existing caisson between the catamaran and the step of pouring water into the hoist ship and seating it on the existing caisson. A caisson installation method using a work boat according to claim 1.