JP2971807B2 - Underwater foundation mound protection net structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underwater foundation mound protection net structure for protecting underwater foundation mounds used for construction of breakwaters, seawalls and marine structures in harbors from waves.

[0002]

2. Description of the Related Art When a breakwater or seawall is constructed with a caisson or other structure, rubble is preliminarily laid on the installation foundation, and an underwater foundation mound is provided. The breakwaters and seawalls will be built continuously on the mound.

When a structure such as a caisson is installed on the underwater foundation mound, it may not be possible to continuously install the structure after the construction of the underwater foundation mound due to its construction scale, weather conditions and the like. In such a case, before the next structure is installed, the stone of the underwater foundation mound may be blown off (run away) by the impact of the waves. In particular, at the base of the end of the existing structure, the waves tend to concentrate, and the stones are blown (washed), creating holes in the underwater foundation mound. In many cases, the properties are impaired, and considerable time is spent repairing the holes.

[0004] As a method for preventing the stones of the underwater foundation mound from being blown off by the impact of such waves, a method of preventing the stone from being thrown at the base of the end structure conventionally installed on the underwater foundation mound is as follows.
Concrete stiffening blocks have been installed that are heavy (non-moving) due to the impact of waves, and have been used as weights to protect the stones of the underwater foundation mound from being blown off.

[0005]

The protection of the underwater foundation mound by installing a concrete stiffening block of a weight that does not fly due to the impact of the waves described above is an obstacle to the installation of the next structure such as a caisson. It will be necessary to remove the consolidation blocks on the underwater foundation mound at the base of the existing end structure.

[0006] However, the conventional concrete stiffening block requires a considerable amount of time for installation and removal operations. The reason is that the size of each block is limited due to the restriction of the hanging load of the crane ship used for the installation of the concrete block, and the number of blocks required to protect the underwater foundation mound is limited. The reason is that the number increases.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned disadvantages of the prior art, to suppress the movement of the basic rubble of the underwater foundation mound, and to reduce the area subjected to the impact of waves to reduce the weight of the underwater foundation mound. It is an object of the present invention to provide an underwater mound protection net structure having an extended protection range.

[0008]

An underwater mound protection net structure according to the present invention comprises a chain or a wire or the like for preventing the movement of foundation rubble in an outer frame formed by assembling a steel frame in a plane. The net formed by is attached. In this way, by attaching the net for preventing the movement of foundation rubble in the steel outer frame, it is possible to prevent the damage of the underwater foundation mound by catching the rubble flying by the net, and the net structure is flat. Because of the steel outer frame and the net, the area that receives the waves is very small, and the weight required for being not moved by the waves can be significantly reduced. This makes it possible to reduce the required weight per piece and to widen the protection range of the underwater foundation mound, as compared with the conventional concrete stiffening block. As a result, the underwater foundation mound protection net structure of the present invention has improved installation and removal workability, and can be installed and removed in a short time.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The planar steel outer frame of the underwater foundation mound protection net structure of the present invention has a size and a shape due to the protection range of the underwater foundation mound and the geometrical restrictions on installation. It is determined. For example, as shown in FIG. 5, when protecting the underwater foundation mound 52 at the corner of the caisson 51, a square steel outer frame 53 is used as shown in FIG. It is also possible to use three frames 53, and as shown in FIG.
A combination of a rectangular steel outer frame 54 and a square steel outer frame 53 may be used, or an L-shaped steel outer frame 55 as shown in FIG. 5C. Further, when the size of the steel outer frame is increased, as shown in FIG. 6, a reinforcing frame 62 may be incorporated so as to further partition the inside of the steel outer frame 61 to reinforce the strength. When protecting the underwater foundation mound at the base of the round caisson, it goes without saying that the steel outer frame has a curved shape along the curved portion of the round caisson.

[0010] As a material of the steel outer frame of the present invention, round steel, steel pipe, mold steel and the like can be used, but in order to secure the required weight of the net structure determined by the wave conditions, the inside of the steel pipe is required. And the inside of the mold steel may be filled with concrete, sand, or the like.

[0011] The mesh of the net attached to the steel outer frame of the present invention is determined by the size of the rubble used for the underwater foundation mound to be protected, and the pitch at which it is installed can be set as a grid. Although it may be from only one direction, it is necessary to have a shape and a size that can at least prevent the movement of the basic rubble.

The connection of the net to the steel outer frame or the reinforcing frame may be of any structure as long as it is not destroyed by the movement of the foundation rubble, but the mounting piece is attached to the steel outer frame.
Connecting the net to the mounting piece by a shackle is simple in structure. The connecting portion of the net needs to have strength not to be destroyed by the movement of the foundation rubble. In addition, the net can be formed of a chain or a wire, but it must have a strength at least not to be cut by the movement of the basic rubble.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the net structure for protecting underwater foundation mounds of the present invention will be described below with reference to FIGS.
It will be described based on. 1 is an overall plan view of a square underwater foundation mound protection net structure of the present invention, FIG. 2 is an enlarged explanatory view of an essential part showing an example of connection of a net formed by a chain to a steel outer frame, and FIG. A plan view showing a state in which six square underwater foundation mound protection net structures of the present invention are installed at the base of the existing caisson on the underwater foundation mound,
FIG. 4 is a sectional view of FIG.

1 and 2, reference numeral 1 denotes a square net structure for protecting an underwater foundation mound, 2 denotes a steel outer frame formed by welding or bolting round steel into a flat square shape,
Reference numeral 3 denotes a mounting piece welded and fixed to the inner surface side of the steel outer frame 2 at a predetermined interval, 4 denotes a chain mounted in a grid at a predetermined pitch to form a net in the steel outer frame 2, and 5 denotes a chain 4.
A shackle connecting both ends to the mounting piece 3 forms a net of chains 4 in a grid at predetermined intervals in the steel outer frame 2. If the net structure 1 is installed on the underwater foundation mound, the underwater foundation The mound's foundation is designed to prevent the movement of the rubble by the impact of the waves.

The mesh spacing of the chains 4 forming the net of the net structure 1 is determined by the size of the base rubble forming the underwater foundation mound, and is set to a size such that the base rubble does not move off the mesh of the chain 4. In addition, the connection of both ends of the chain 4 to the steel outer frame 2 was performed by the mounting piece 3 and the shackle 5. However, if the connection portion has a strength not to be broken by the movement of the basic rubble by the impact of the wave, Can be used. Further, the net structure 1 is configured to have a weight that does not move by the impact of a wave.

With the above configuration, the net structure 1 is constituted by a net-like net formed by the steel outer frame 2 and the chain 4 and has a planar shape, so that it receives waves. The area is very small as compared with the conventional stiffening block, so that the weight of the block itself can be greatly reduced because it is not moved by the waves. For this reason, the net structure 1 can reduce the required weight per piece compared with the conventional stiffening block, can be easily installed and removed, and can extend the protection range of the underwater foundation mound. .

As shown in FIGS. 3 and 4, the net structure 1 according to the present invention is composed of an end caisson 12 partly continuously constructed on an underwater foundation mound 11 made of foundation rubble piled on the sea floor. To protect the two corner roots, a crane ship (not shown) is moved to the vicinity of the end caisson 12, and the net structure 1 is suspended by the crane at the two corner roots of the end caisson 12. Three pieces are installed and installed as shown in FIGS.

[0018] By installing and arranging in this way,
Underwater foundation mounds 11 are covered with three net structures 1 at two corner roots of the existing end caisson 12 where waves are easily concentrated. For this reason, the movement of the underwater foundation mound 11 due to the impact of the waves of the basic rubble is prevented by the lattice-like chain 4 forming the net of the net structure 1, and a hole is formed in the underwater foundation mound 11 due to the movement of the basic rubble. It will not be done.

When a new caisson is to be installed continuously to the existing end caisson 12, a crane ship (not shown) is moved to the vicinity of the end caisson 12 and the end caisson 1 is moved.
If the three net structures 1 installed and installed at the two corner bases are lifted and removed, the caisson is immediately connected to the end caisson 12 without repairing the underwater foundation mound 11. Can be installed.

[0020]

The underwater mound protection net structure of the present invention has a planar shape composed of a steel outer frame and a net, so that the area for receiving waves is smaller than that of the conventional stiffening block. It is extremely small, and the weight of itself for being prevented from being moved by waves can be greatly reduced.
For this reason, the net structure can reduce the required weight per piece as compared with the conventional consolidation block, can be easily installed and removed, and can extend the protection range of the underwater foundation mound. .

[Brief description of the drawings]

FIG. 1 is an overall plan view of a square underwater foundation mound protection net structure of the present invention.

FIG. 2 is an enlarged explanatory view of an essential part showing an example of connection of a net formed by a chain to a steel outer frame.

FIG. 3 is a plan view showing a state in which six square underwater foundation mound protection net structures of the present invention are actually installed at the base of an existing caisson on the underwater foundation mound.

FIG. 4 is a sectional view of FIG. 3;

5A and 5B show an example of installation of a net structure according to the present invention. FIG. 5A shows a case where three square net structures are used, and FIG. 5B shows a square net structure and a rectangular net structure. FIG. 3C shows the case of an L-shaped net structure when the objects are combined.

FIG. 6 shows an example of installation of a reinforcing frame on a steel outer frame. FIG. 6 (a) shows a rectangular steel outer frame, and FIG.
The case of a steel outer frame of a mold is shown.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Net structure 2, 53, 54, 55, 61 Steel outer frame 3 Mounting piece 4 Chain 5 Shackle 11, 52 Underwater foundation mound 12 End caisson 51 Caisson 62 Reinforcement frame

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takuya Kitamura 4-33, Kitahama, Chuo-ku, Osaka-shi, Osaka Prefecture Inside Sumitomo Metal Industries, Ltd. (72) Inventor Naoki Hayashi 2254 Ao, Aoji, Kashima-shi, Ibaraki Prefecture Ministry of Transport Inside the second port construction bureau Kashima port construction office (72) Inventor Yoshikazu Moriya 2254 Ao, Oaza, Kashima city, Ibaraki prefecture Inside the second port construction bureau Kashima port construction office, Ministry of Transport No. 2254 Inside the Kashima Port Construction Office, Second Port Construction Bureau, Ministry of Transport No. 2254 Ao, Kashima City, Kagoshima Port Construction Bureau, Ministry of Transport, Kashima Port Construction Office (72) Inventor Kazuyuki Soma 2 Oaza Ao, Kashima City, Ibaraki Prefecture 254 No. 2 in the Kashima Port Construction Office of the Ministry of Transport, Second Port Construction Bureau (72) Inventor Jun Fukukawa 2254 Ao Ao, Kashima City, Ibaraki Prefecture, No. 2 in Kashima Port Construction Office of the Second Port Construction Bureau, Ministry of Transport 1-3-8 Nihombashi Bakurocho, Chuo-ku The Japan Maritime Hoisting Technology Association (56) References JP-A-59-122626 (JP, A) Japanese Patent Publication No. 8-6341 (JP, B2) (58) Survey Field (Int.Cl. ⁶ , DB name) E02B 3/08 E02D 27/52 E02D 23/02

Claims (1)

(57) [Claims] 1. A protection structure for an underwater foundation mound formed by laminating stones on the sea floor, wherein a net for preventing movement of foundation rubble is provided in an outer frame formed by assembling a steel frame in a plane. An underwater foundation mound protection net structure characterized by being attached.