JP2013174055A - Underwater obstacle crushing device and underwater obstacle crushing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an underwater obstacle crushing device that can cope with a large-depth construction that it is difficult even for a rock crushing rod fall type crushing device and an underwater back hoe with a breaker to cope with.SOLUTION: An underwater obstacle crushing device is a device based upon a ground improvement ship having multiple casing pipes connected. The crushing device includes a work ship 12, a stood leader mast 14, a casing pipe 16 elevated and lowered along the leader mast 14, a vibrohammer 18 fixed to a head portion of the casing pipe, a crushing member 3 fixed to the tip of the casing pipe, a winch 21 elevating and lowering the casing pipe, and a pipe keeper portion 23 supporting the case pipe from sideway. With this invention, an underwater obstacle can be crushed in a pinpoint manner even during large-depth construction that it is difficult even for a rock crushing rod fall type crushing device and an underwater back hoe with a breaker to cope with. Depth control cannot be performed by a crushing rod fall method etc., but can be performed with this invention.

Description

  The present invention relates to an apparatus and method for crushing underwater obstacles such as caissons and breakwaters submerged in water, and more specifically, crushing at the tip of a casing pipe equipped in a ground improvement ship such as an SCP ship or an SD ship. It is invention regarding the apparatus and method for attaching a member and crushing an underwater obstacle.

  Due to the tsunami generated by the 2011 off the Pacific coast of Tohoku Earthquake, the breakwater was destroyed at the port and many large structures such as caissons were overturned. Is still dead. In particular, falling caissons and breakwaters swept away under the surface of the water due to the tsunami will obstruct the vessel's navigation if left as they are. It is an urgent issue.

  In addition, in preparation for the tsunami attack, it is necessary to quickly remove underwater obstacles such as a fallen caisson and a fallen caisson from the mound in order to install a new caisson and construct a breakwater in the harbor in the affected area. is there.

  Furthermore, in preparation for large-scale tsunamis that are expected to occur in Japan in the future, even if underwater obstacles such as fallen caissons occur, new disaster recovery means that can quickly remove them at low cost will be established. It is also necessary to keep it.

  As a crushing means for removing the underwater obstacle, a method of crushing the underwater obstacle with a crushing rod dropping type crushing device or an underwater backhoe equipped with a breaker has been proposed. However, in the crushed rock dropping type crushing device, it is difficult to crush the crushing object at a pinpoint because it is affected by the tidal current during the fall. In addition, there is a problem that the falling energy of the crushed rock is attenuated in the process of falling in water, so that it cannot cope with construction at a deep depth. Furthermore, even when an underwater backhoe equipped with a breaker is used, there is a problem that it cannot cope with construction at a large depth.

  In view of the above-described problems, an object of the present invention is to provide an underwater obstacle crushing apparatus and an underwater obstacle crushing method that can cope with construction at a depth that is difficult to handle with a crushing rod dropping type crushing apparatus or an underwater backhoe with a breaker. There is.

  The above-described object is achieved by a leader mast erected on a work ship, a casing pipe provided so as to be movable up and down along the leader mast, This is achieved by an underwater obstacle crushing device having a crushing member and a vibro hammer fixed to the head side of the casing pipe and applying a striking force to the crushing member. The vibro hammer may be electric or hydraulic.

  The above object is also a method for crushing underwater obstacles using a ground improvement ship having a casing pipe equipped with a vibro hammer and a leader mast for raising and lowering the pipe. Achieved by attaching a crushing member to crush the obstacle, lowering the casing pipe, hitting the crushing member at the tip of the crushing member against the underwater obstacle, and hitting and crushing the underwater obstacle with a striking force by a vibro hammer Is done.

  Moreover, the said objective is achieved by the crushing member attached to the front-end | tip of the casing pipe of a ground improvement ship.

The leader mast, casing pipe, and vibro hammer required for carrying out the present invention are basic equipment that is usually provided for ground improvement ships such as SCP ships and SD ships. Therefore, simply by attaching a crushing member to the casing pipe of an existing ground improvement ship, the ground improvement ship can be remodeled into an underwater obstacle crushing device. Can also be implemented.
Therefore, according to the present invention, it is possible to manufacture the underwater obstacle crushing apparatus at a much lower cost and more easily than when a new crushing ship is newly designed and built.
In addition, work vessels that could only be used for ground improvement until now can be used to crush underwater obstacles by simply attaching a crushing member to the tip of the casing pipe. It can spread and greatly enhance its utility value.
In addition, the extremely simple structure of simply attaching a crushing member to the tip of the casing pipe of an existing ground improvement ship makes it possible to respond promptly at a low cost even when a caisson falls due to a large-scale tsunami. Can contribute to the improvement and disaster recovery.

  In addition, it was also considered to use the ground improvement ship for crushing the rock breaking rod drop method, but in order to use the winch of the ground improvement ship with this method, it is necessary to stop the feeding of the wire according to the landing of the rock breaking rod. There is. That is, a dedicated winch is required, and it cannot be handled by the winch of an existing ground improvement ship. On the other hand, in the present invention, since such a rock breaking rod dropping method is not adopted, the winch of the existing ground improvement ship can be used as it is, and the ground improvement ship can be modified to an underwater obstacle crushing apparatus at low cost. There is.

  According to the present invention, the crushing member is fixed to the tip of the casing pipe, and the casing pipe is connected to the leader mast on the work ship. Therefore, even if the crushing operation is affected by the tidal current, the crushing member can be reliably hit and crushed without the crushing member being washed away.

  Moreover, the ground improvement ship used as the base of the crushing apparatus of this invention is normally equipped with the pipe keeper part which supports a casing pipe from the side. That is, the casing pipe is laterally supported at least at two points (two points in the vertical direction) of the connecting portion to the leader mast and the pipe keeper portion, so that the casing pipe can be maintained vertically or close to it. Therefore, the crushing member can be abutted against the object at a pinpoint only by adjusting the ship position so that the tip of the casing pipe is directly above the crushing object point. In addition, there is no need for diving assistance work such as alignment by divers.

  Moreover, as a result of supporting the casing pipe laterally at two points as described above, even if the casing pipe is affected by the tidal current, the casing pipe can be prevented from swinging and can be pinned against a predetermined portion to be crushed.

  In addition, ground improvement ships such as SCP ships and SD ships are equipped with multiple casing pipes, so even when crushing large underwater obstacles, such as fallen caissons, crush multiple points of the object at the same time. And can be removed by rapid construction.

  In addition, ground improvement ships such as SCP ships and SD ships can be equipped with a casing pipe of about 60m, and another casing pipe can be added to this casing pipe. Even under large-scale construction that is difficult to handle with an underwater backhoe with a breaker of the type and a breaker, the device of the present invention can reliably crush underwater obstacles at a pinpoint.

  In addition, when using a crushing rod dropping type crushing device, it is impossible to manage the depth, but according to the present invention, crushing depth management such as crushing up to -20 m is possible.

  Moreover, the vibro hammer installed in the casing pipe head of the ground improvement ship is always above the water surface during construction and does not flood. As described above, the vibro hammer itself is not submerged, so that it is not necessary to take a waterproof measure for the vibro hammer, and there is no trouble caused by the submergence. .

  In the present invention, since the vibro hammer is not submerged during construction, not only a hydraulic hammer but also an electric hammer can be used. Even if a hydraulic vibro hammer is used, the hammer is not submerged during construction, so environmental pollution due to oil leakage from the hammer does not occur.

  Moreover, in this invention, the striking force of the vibro hammer by the side of a work ship is propagated to the crushing member of the front-end | tip via a casing pipe. As a result, there is a merit that the crushing energy is less attenuated compared to the method of dropping a crushed rock rod underwater.

  In addition, for the crushing member used in the present invention, a plurality of types having different shapes are prepared (for example, a plurality of types having different numbers, shapes, sizes, etc. of chisels and blades are prepared), and each can be attached / detached / replaceable You may comprise as. Thereby, the crushing member most suitable for crushing a target object can be selected according to the property and situation of crushing object.

It is a side view which shows the underwater obstacle crushing apparatus of this invention. It is a top view which shows the underwater obstacle crushing apparatus of this invention. It is a front view which shows the underwater obstacle crushing apparatus of this invention. It is a front view which shows the casing pipe which equipped with the vibro hammer in the head and equipped with the crushing member in the front-end | tip. It is the one side sectional view showing a crushing member, and a sectional view along an aa line. It is a figure which illustrates the construction procedure at the time of crushing the fallen caisson which is an underwater obstacle. They are the one-side sectional view which shows the modification of a crushing member, and sectional drawing along the bb line. It is the one side sectional view which shows the modification of a crushing member, and sectional drawing along a cc line. It is the one side sectional view which shows the modification of a crushing member, and sectional drawing along the dd line.

Hereinafter, an SCP ship (sand compaction pile ship) will be cited as an example of a ground improvement ship, and a specific embodiment of the present invention will be described.
The ground improvement ship that can be used in the present invention is not limited to the SCP ship, and other ground improvement ships equipped with a leader mast, casing pipe, and vibro hammer, for example, an SD ship (sand drain ship) can be used. is there.

(Underwater obstacle crusher)
First, based on FIGS. 1-3, schematic structure of an underwater obstacle crushing apparatus is demonstrated.

  The underwater obstacle crushing apparatus 1 of the present invention is an apparatus based on an SCP ship which is a ground improvement ship. This underwater obstacle crushing apparatus 1 has substantially the same configuration as that of a general SCP ship used for the implementation of the SCP method, except that the crushing member 3 is provided.

  The underwater obstacle crushing apparatus 1 is an apparatus based on an SCP ship, and this crushing apparatus includes a work ship 12 composed of a carriage, a plurality of leader masts 14 erected on the work ship, and each leader mast. A casing pipe 16 that can be moved up and down along the electric motor, an electric vibrator hammer 18 fixed on the head side of the casing pipe, a crushing member 3 fixed on the front end side of the casing pipe, and the casing pipe A winch 21 for lifting and lowering a pipe, a pipe keeper 23 for supporting a casing pipe that moves up and down from the side, and a GPS positioning system (not shown) for moving and setting a work ship on a crushing point doing.

  The leader mast 14 is erected on the work boat and plays a role of guiding the casing pipe 16 up and down in the vertical direction.

  As shown in FIG. 1, the casing pipe 16 made of a steel pipe is connected to the leader mast 14 via a guide clamp 15 that can be moved up and down along the leader mast 14. The casing pipe 16 plays a role of feeding a pile material into the ground in the SCP method. In the underwater obstacle crushing method of the present invention, the crushing member 3 attached to the tip of the underwater obstacle crushes mainly abuts on the underwater crushing object and plays a role of transmitting the striking force of the vibro hammer 18 to the crushing member 3. For example, another casing pipe can be added to the casing pipe 16 by the technique of the applicant's prior application (Japanese Patent Laid-Open No. 2006-214235).

  The vibro hammer 18 is an electric vibrator and is fixed to the head of the casing pipe 16 with bolts. In the SCP method, the vibro hammer 18 is vibrated to cause the casing pipe 16 to penetrate into the ground. In the underwater obstacle crushing method of the present invention, the crushing impact force is applied to the crushing member 3 at the tip of the casing pipe. The vibro hammer 18 is always on the water surface during construction, and will not be submerged even when the casing pipe 16 is lowered to the lowest position. In the present embodiment, an electric hammer is used as an example. However, a vibro hammer usable in the present invention is not limited to this, and a hydraulic hammer may be used.

  The winch 21 is fixed on the work boat 12. The wire rope fed out from the winch 21 is connected to a vibro hammer 18 fixed to the casing pipe head. In the SCP method, the casing pipe is lowered to the ground to be improved, and the casing pipe penetrated into the ground is taken out. In the underwater obstacle crushing method of the present invention, the casing pipe 16 having the crushing member 3 at the tip thereof is lowered and lifted toward the crushing target.

  As shown in FIG. 2, the pipe keeper portion 23 is provided in a recess 24 formed on the bow side of the work boat 12. The pipe keeper 23 has an insertion hole 25 that communicates with the sea surface, and the casing pipe 16 is raised and lowered through the insertion hole. In the SCP method, the pipe keeper portion 23 plays a role of supporting the casing pipe from the side to ensure vertical accuracy. In the underwater obstacle crushing method of the present invention, when the crushing member 3 is abutted against the crushing target, it plays a role of supporting the casing pipe from the side.

  The pipe keeper portion 23 is provided with pipe damaging means such as a rubber tire or a rubber roller, and the pipe damming means is disposed close to the casing pipe peripheral surface so as to dampen the casing pipe 16 during construction. Also good. For example, a plurality of rubber tires may be provided in the pipe keeper portion 23 so as to surround the casing pipe peripheral surface from four directions. Alternatively, two or more rubber rollers in contact with the casing pipe peripheral surface may be provided in the pipe keeper portion 23. Thereby, the shake of the casing pipe 16 during construction can be further suppressed, and the crushing member 3 at the tip of the casing pipe can be continuously abutted against the object to be crushed pinpoint.

  Further, in this embodiment, as shown in FIG. 3, a ground improvement ship having three casing pipes is shown as a representative example. However, the configuration of the present invention is not limited to this, and two or four or more series are installed. It is also possible to use a ground improvement ship.

  Further, when the depth of the object to be crushed is deep, another casing pipe can be added to the casing pipe 16.

(Crushing member)
Next, based on FIG.4 and FIG.5, the structure of the crushing member 3 attached to the front-end | tip of the casing pipe 16 is demonstrated.
FIG. 4 is a front view showing the casing pipe 16 having the vibro hammer 18 at the head and the crushing member 3 attached to the tip.
FIG. 5 is a half sectional view showing the crushing member 3 and a sectional view taken along the line aa.

  As shown in FIG. 5, the crushing member 3 includes a cylindrical portion 31 fixed to the tip of the casing pipe, four rod-shaped chizels 34 fixed to the tip of the cylindrical portion 31, and a cross rib for reinforcing the chisel. 36.

  As shown in FIG. 4, the cylindrical portion 31 of the crushing member shown in FIG. 5 is fixed to the casing pipe in a state of being in contact with the front end surface of the casing pipe. The fixing means is not particularly limited, and can be fixed by, for example, bolts or welding. When importance is attached to the detachability of the crushing member 3 with respect to the casing pipe 16, the bolt is fixed with a bolt, and when importance is attached to the mounting strength, it is fixed with welding.

  The cross rib 36 is configured to have a cross shape as shown in FIG. A part of the cross rib 36 is welded to the inner wall of the cylindrical portion 31, and a chisel 34 is welded to the side portion of the portion protruding from the lower end of the cylindrical portion 31.

  The four chisels 34 protrude from the lower end of the circular head 31 at equal intervals. The circumferential surface of each chisel 34 is welded to the side surface of the cross rib 36 projecting from the cylindrical portion 31, and the head of each chisel 34 is welded to the lower end of the cylindrical portion 31. Further, each chisel 34 has a sharp tip portion formed so that the tip surface has a single letter shape.

(Underwater obstacle crushing method)
Next, a fallen caisson submerged in water will be cited as a specific example of the underwater obstacle, and a method for crushing the underwater obstacle using the above-described apparatus will be described.

  When a large-scale tsunami occurs, many structures such as caissons fall over in the harbor, and many of them fall into the seabed. Large structures such as a fallen caisson lying on the sea floor will hinder the navigation of the ship if left unattended, so it is necessary to remove them immediately to secure the route. The construction procedure for crushing and removing such a fallen caisson is as follows.

1. Advance preparation Considering the size, shape, and tipping situation of the caisson, which is the target for underwater crushing, determine the crushing layer thickness (thickness to be crushed in one crushing process). The caisson crushing operation is performed by repeating thin layer crushing. That is, as shown in FIGS. 6A and 6B, the caisson is divided into a plurality of layers according to the depth, and the crushing of each layer is repeated.

  Before crushing is started, the crushing member 3 shown in FIG. 5 is attached to the tip of the casing pipe 16 as shown in FIG. In this step, the upper end of the cylindrical portion 31 of the crushing member 3 is butted against the lower end of the casing pipe 16, and both are fixed by welding or bolts.

2. Caisson's thin layer crushing Use the GPS positioning system on the work ship to move and set the work ship to the crushing point.

  Next, the casing pipe 16 is rolled down, and the crushing member 3 at the tip thereof is brought close to the crushing point. At this time, the ship position is finely adjusted, and the crushing member 3 is positioned so as to come directly above a predetermined crushing point.

  As shown in FIG. 6 (A), when the crushing member 3 reaches a depth before the upper end depth of the planned crushing layer, the vibro hammer 18 is operated. Subsequently, the casing pipe 16 is rolled down at a low speed, and the crushing member 3 at the tip of the casing pipe 16 is abutted against the caisson planned crushing layer. The striking force of the vibro hammer 18 above the water surface propagates to the underwater crushing member 3 through the casing pipe 16, and crushing of the caisson is started by the striking force.

  During the impact crushing, the casing pipe 16 is supported from the side by two points (two points in the vertical direction) of the guide clamp and the pipe keeper portion connected to the leader mast. Therefore, since the casing pipe 16 can be maintained in a substantially vertical state without being inclined, even if the casing pipe 16 is subjected to a striking reaction force during the crushing operation, no positional deviation occurs. Therefore, by supporting two points from the side as described above, a striking force can be continuously applied to the object to be crushed pinpoint.

  When the crushing is advanced and the lower end of the expected crushing depth for one layer is reached, the casing pipe 16 is rolled up and the vibro hammer 18 is stopped. Subsequently, the work ship is moved to another crushing point of the same crushing layer.

  The above procedure is repeated to complete the crushing for one layer.

3. Debris removal for one layer The crushed debris is removed with a grab dredger.

4). Confirmation of the finish of one layer Confirm the finish of removal of one layer by depth survey.

5. Repeating thin layer crushing and removal Repeat steps 2-4 above to crush and remove caisson to the planned removal depth shown in FIG.

  In this embodiment, the case where the underwater obstacle made of caisson is partially removed, that is, the part above the planned removal depth is explained, but the whole underwater obstacle may be crushed and removed. Is possible.

  According to the present invention described above, an underwater obstacle can be crushed pinpointly without being affected by a tidal current even in a large-depth construction that is difficult to handle with a crushing rod dropping type crushing device or an underwater backhoe with a breaker. In addition, the crushing depth can be managed because the crushing member is abutted against the object using the casing pipe equipped on the work boat.

(Modification)
The above-described embodiment is an example of an embodiment of the present invention, and various modifications are included in the technical scope of the present invention.

  For example, the application of the present invention is not necessarily limited to crushing a fallen caisson, and can be used, for example, for crushing a bedrock on the seabed.

Moreover, the crushing member utilized by this invention is not limited to a form as shown in FIG.
For example, as shown in FIG. 7, instead of the cross rib, a cross blade 41 having a longer shape may be provided.
Further, as shown in FIG. 8, instead of a plurality of chisels and cross ribs, a single blade blade 42 may be provided as a crushing means, and a rib 43 may be provided as a reinforcing member.
Further, as shown in FIG. 9, instead of a plurality of chisels and cross ribs, one large chisel 45 may be provided as a crushing means, and ribs 46 may be provided as reinforcing members.

1 Underwater obstacle crushing device 3 Crushing member 12 Work ship (truck)
14 Leader mast 15 Guide clamp 16 Casing pipe 18 Vibro hammer 21 Winch 23 Pipe keeper part 24 Recess 25 Insertion hole 31 Cylindrical part (shaft part)
34 Chisel (Rod)
36 Cross rib 41 Cross blade 42 Blade (single blade)
43 Rib 45 Chisel 46 Rib

Claims (3)

A leader mast erected on the work boat,
A casing pipe provided so as to be movable up and down along the leader mast;
A crushing member fixed to the tip side of the casing pipe, for crushing underwater obstacles,
An underwater obstacle crushing device, comprising: a vibro hammer fixed to a head portion side of the casing pipe and imparting a striking force to the crushing member. A method of crushing an underwater obstacle using a ground improvement ship comprising a casing pipe with a vibro hammer and a leader mast for raising and lowering the pipe,
Attach a crushing member to crush underwater obstacles at the tip of the casing pipe,
Lower the casing pipe and hit the crushing member at the tip of the casing pipe against an underwater obstacle.
An underwater obstacle crushing method, characterized by hitting and crushing the underwater obstacle with a striking force of a vibro hammer.   The crushing member used by the method of Claim 2 and attached to the front-end | tip of a casing pipe.