JP2003171918A - Back-fill structure and back-fill construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a back-fill structure and a back-fill construction method achieving reduction of an earth pressure, having a screen effect and capable of shortening a construction period. <P>SOLUTION: A back-fill is composed by stacking a multiplicity of bag filled covering materials 1 in layers in a back face of a caisson 23. In the bag filled covering material 1, filling materials 5 are filled in a fiber made net bag 3, and the earth pressure acting on the caisson 23 can be extensively reduced. By selecting a proper particle size for the filling materials 5, the bag filled covering materials 1 can function as a filter. A plurality of the bag filled covering materials 1 are suspended from a suspending jig 31 and they are collectively installed in a predetermined position. Since there is no need for fine accuracy control such as leveling of a substrate or combination in installation, the construction period can be shortened. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a backfill structure and a backfill construction method for seawalls and retaining walls.

[0002]

2. Description of the Related Art Conventionally, the backfill of revetments and retaining walls has been constructed by putting in good quality earth, sand, gravel and crushed stone and compacting it well, contributing to the reduction of earth pressure and functioning as a drainage layer. FIG. 11 shows an example of a conventional caisson type landfill backfill structure. A caisson 23 is provided at the boundary between the sea side and the land side.
It is provided above. The backfill material 27 is piled up in a triangular shape on the land side of the caisson 23 and the foundation rubble 21, and a sandproof sheet 29 is laid at the boundary between the backfill material 27 and the landfill material 25 to configure backfilling. There is.

[0003]

For revetments constructed in relatively deep water, the sizes of revetment caissons, sheet piles, etc. are often determined in consideration of sliding to the sea side after the completion of an earthquake. . During sliding, earth pressure acting on the caisson is applied through backfilling. The size of caisson can be reduced by reducing the earth pressure. Therefore, in order to reduce the construction cost of the entire revetment, further reduction of earth pressure acting on the caisson is desired.

Further, backfilling the seawall caisson has a problem that it takes a long period of time for molding, installing a sandproof sheet, and the like.

If the backfill material does not perform a sufficient drainage function, the reclaimed earth and sand flow under the mound to the sea side, leading to depression of the reclaimed land. Therefore, it is required to secure the filter effect of the backfill material.

The present invention has been made in view of the above problems, and an object of the present invention is to achieve a reduction in earth pressure, a filter effect, and a backfilling structure which can be constructed in a short period of time. And to provide a backfill construction method.

[0007]

In order to achieve the above-mentioned object, the first invention is characterized in that a plurality of coating materials filled with a filling material are installed inside a net bag. It has a backfill structure.

[0008] As the filling material, gravel, crushed stone, artificial gravel,
You may use granular materials, such as the gravel whose specific gravity was adjusted and the molten slag stone material produced by recycling. When used in water, the specific gravity is preferably higher than that of water.

As the net bag, a net made by knitting fibers can be used, and is formed by a knotless net, a Russell net, a frog net, or the like. The Russell net has the characteristic that the broken part is less likely to spread than other knotless nets. The fibers used can be made of synthetic fibers such as nylon and polyester, or natural fibers such as cotton and hemp.

According to the first aspect of the present invention, a back-filling structure is constructed by installing a plurality of coating materials filled with a filling material inside a mesh bag.

A second aspect of the present invention is constructed by using a plurality of coating materials in which a filling material is filled in a net bag, and a plurality of types of coating materials having different particle diameters of the filling material are installed in layers. It is a backfill structure characterized by being configured as follows.

According to the second aspect of the invention, a back-filling structure is constructed by installing a plurality of covering materials filled with a filling material inside the mesh bag. At this time, a plurality of types of coating materials having different particle sizes of the filling material are manufactured, and the coating materials of each type are installed in layers according to the particle diameter of the filling material.

A third aspect of the present invention is a backfilling structure characterized in that a backfill having the above-mentioned backfilling structure is provided behind a structure, and a light weight fill is provided between the structure and the banking. is there.

In the third invention, the embankment having the above-mentioned backfilling structure is provided at a position slightly behind the structure. A lightweight embankment is provided between the structure and the embankment. The earth pressure of the general part is received by the embankment. The earth pressure acting on the structure is
Only light embankment will be used and reduced.

A fourth aspect of the invention is to hang a plurality of coating materials filled with a filling material inside a net bag on a hanging jig, and to install the coating materials at predetermined positions. And a backfilling construction method.

According to the fourth aspect of the invention, a plurality of covering materials in which the filling material is filled in the net bag are hung on a hanging jig. The covering material is installed at a predetermined position. Since a plurality of covering materials are suspended and installed in a lump, it is easy to manufacture and install, and does not require a long construction period.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a schematic configuration diagram of a bag filling material 1. The bagging covering material 1 is called a filter unit, and is made of a fiber mesh bag 3 and a filling material 5 packed therein.

The net bag 3 is a net made by knitting fibers.
The fibers used may be synthetic fibers or natural fibers. Also,
You may use the recycled fiber recycled from a plastic bottle etc. As the filling material 5, artificial stone material or recycled stone material may be used in addition to crushed stone, gravel and the like.

A hanging ring 7 is provided on the top of the net bag 3. The hanging ring 7 is used as a jig for hanging on a crane or the like. The suspension ring 7 is made of a material that is durable and has a strength that can withstand the weight of the bagging covering material 1.

FIG. 1 (a) shows a state in which the bagging covering material 1 is lifted up using the hanging ring 7. FIG. 1B shows a state in which the bagging covering material 1 is installed. It is a feature of the bagging and covering material 1 that the covering area increases in the installed state as compared with the suspended state.

However, if the amount of the filling material 5 is too large, the filling material 5 is installed in a shape that is almost the same as the lifted shape. If the amount of the filling material 5 is too small, the mesh of the mesh bag 3 in the installed state becomes loose, and the bag covering material 1 is not integrated as a single body.

Various shapes can be considered for the bag filling material 1. FIG. 2 shows an example of the mesh bag 3 that constitutes the bag-filling covering material 1. FIG. 2A shows a T-shaped net bag 3a having a round bottom. FIG. 2 (b) shows an envelope-shaped woven net bag 3b.

FIG. 3 shows a standard manufacturing method of the bagging dressing 1. First, as shown in FIG. 3A, the manufacturing frame 11
Is installed, and the net bag 3 is set inside the manufacturing frame 11 with the net mouth open. When the mesh bags 3 are to be multiplexed, they are multiplexed at this stage.

The manufacturing frame 11 serves as a frame for fixing the net mouth and is also used as a box for measuring the amount of the filling material 5 to be charged. Using the backhoe 13, etc., the filling material 5 is put into the net bag 3 until the manufacturing frame 11 is full.

After that, as shown in FIG. 3B, the net bag 3
Attach the hanging ring 7 to the upper part of the net mouth. As shown in FIG. 3 (c), the bagging covering material 1 is made by the hanging ring 7 using a crane or the like.
Is temporarily suspended, and the mouth is tied with a lashing rope 17. Figure 3
As shown in (d), the manufacturing frame 11 is attached to the truck crane 1.
The production frame 11 is pulled out as shown in FIG.

A large number of bag-filled covering materials 1 are prepared in a construction yard by the above manufacturing method. The bagging coating material 1 is lifted by a lifting machine, installed at a predetermined place, and stacked to construct backfilling.

A back-filling structure using the bag-filling covering material 1 will be described. FIG. 4 shows a cross-sectional view of the backfill structure according to the first embodiment of the present invention. The structure of FIG. 4 is one in which the present invention is applied to the backfill portion of a caisson type reclaimed seawall. Similar cross-sections can be considered for other revetment types and retaining walls.

In FIG. 4, a caisson 23 is provided on the foundation rubble 21 at the boundary between the sea side and the land side. Between the caisson 23 and the landfill material 25, a large number of bag-filling covering materials 1 are stacked in layers to form backfill. A sandproof sheet 29 is laid between the covering material 1 and the landfill material 25.

FIG. 5 is a plan view showing an example of a method of arranging the bagging covering material 1 in layers. As shown in FIG. 5, the even-numbered layer bagging covering material 1a and the odd-numbered layer bagging covering material 1b are stacked alternately so as to fill the gaps therebetween. By arranging in this way, the engagement of the bag filling material 1 can be increased.

The features and effects of the back-filling structure using the bag-filled covering material 1 will be described below. Generally, the earth pressure when stacking the granular materials increases in proportion to the stacking height. However, in the case of a granular material such as the filling material 5 placed in the net bag 3, the earth pressure in the horizontal direction is balanced by the tension of the net material. Therefore, the bagging covering material 1 alone can be regarded as one granular material element without the horizontal earth pressure acting thereon.

When piled up, a normal granular material forms a slope having a slope of repose angle. On the other hand, the bagging covering material 1 can be easily stacked vertically, and even in one row, it can be stacked in a plurality of stages (five or more stages). This is because the bag-filling covering material 1 has flexibility and easily fits on the uneven surface of the installation surface, thereby producing the effect of engagement.

This is the same principle as that of a concrete block having a bite such as a tenon, which has a large horizontal resistance. Concrete blocks must be installed in combination with hozo. On the other hand, the bagging and covering material 1 has a feature that the degree of freedom is large because this is automatically performed.

Depending on the construction conditions, the bagging coating material 1 can be installed in a staggered manner to further enhance the biting effect. By configuring the backfill using the bagging covering material 1, it is possible to greatly reduce the earth pressure acting on the caisson or the like. Therefore, it is possible to contribute to the weight reduction of the caisson and the like and the number of backfill materials.

Further, by selecting an appropriate particle size for the filling material 5, the bag filling material 1 can function as a filter.

Recycled substances can be used for the material of the net bag 3 and the filling material 5, which helps to reduce the environmental load. Especially when artificial lightweight stone materials are used, in addition to the effect of reducing the earth pressure, the ground contact pressure can be reduced, and the effect of suppressing ground subsidence can be expected.

FIG. 6 is a sectional view of a backfill structure according to the second embodiment of the present invention. Here, the filling materials 5 having different particle sizes are used. By placing the bagging covering material 1c having the small particle size filling material 5 in the upper layer and the bagging covering material 1d having the large particle size filling material 5 in the lower layer, and installing them in layers, The filter effect can be increased. In this case, the sandproof sheet can be omitted.

Next, a method for constructing backfilling using the bagging covering material 1 will be described. FIG. 7 shows a plurality of packing materials 1
It is a perspective view which shows the means to install. Hanging jig 31
A plurality of suspending ropes 33 are suspended on. A hook is provided at the tip of the hanging rope 33, and the bagging covering material 1 is hung by the hanging ring 7.

The hanging jig 31 is made of, for example, a steel frame. The hook is preferably an auto release hook 35. The center interval of the suspended bagging dressing 1 is set to be the same as the center interval of the bagging dressing 1 after being laid at the installation site.

Since the diameter of the bag-filling covering material 1 is smaller in the suspended state than in the installed state, basically the bag-filling covering materials 1 do not come into contact with each other in the suspended state. However, in order to prevent the contact frictional force between the adjacent bagging covering materials 1 at the time of hoisting, and to prevent the contact between the bagging covering materials 1 due to the swing in the hoisted state, the length of the hanging rope 33 is increased. The bag-filling covering material 1 may be suspended in a multi-layer structure by dividing the bag into several types.

7 and 8, the length of the hanging rope 33 is 2
The state is shown in which the bag-filled covering material 1 is hung up in a two-layer structure as a type. FIG. 8A is a front view, and FIG. 8B is a side view. As shown in FIG. 8, the lengths of the hanging ropes 33 of the bagging covering material 1 adjacent to each other in the front direction and the side direction are different.

As shown in FIG. 7, the hanging jig 31 on which the bagging covering material 1 is hung is hung by a lifting machine such as a crane and adjusted to the installation position, and then the hanging jig 31 is lowered to bag the bag. Laying the covering material 1. When the hook of the hanging rope 33 is an auto-release hook, the frame may be lowered to automatically remove the hook when the bagging covering material 1 has bottomed on the installation ground and the bagging covering material 1 is laid. it can.

By adopting the above method,
It is possible to efficiently lay a large number of bag filling materials 1 at a predetermined position at one time. In this way, backfilling can be constructed by sequentially laying and stacking the bagging covering material 1 on a predetermined installation surface.

When suspended in a two-layer structure as shown in FIGS. 7 and 8, two layers of the bagging covering material 1 can be laid at a time. Not only the contact prevention effect between the bagging covering material 1 but also
The efficiency of laying work can be improved. The multilayer structure at the time of lifting is not limited to this example, and a multilayer structure of two or more layers is also possible by appropriately setting the length of the hanging rope 33.

When the bagging covering material 1 is hung in a multilayer structure,
The particle size of the filling material 5 filled in each bag-filling covering material 1 may be different depending on the length of the hanging rope 33.
For example, the bagging covering material 1 hung on the short suspending rope 33 has a small filling material 5 with a small particle size, and the bagging covering material 1 hanging on a long hanging rope 33 has a large filling material 5 with a large particle diameter. To have. As a result, a backfill structure having a high filter effect can be easily constructed.

As described above, the installation of the bag-filling covering material 1 does not require fine precision control such as leveling of the base and combination at the time of installation. It is possible to install a large number of the bagging covering materials 1 by suspending them from a frame or the like. Since the outline of the suspended shape and the installed shape can be known in advance from the specifications of the net bag 3 and the filling material 5, the suspension method can be designed in advance. Therefore, the work period can be shortened, and in particular, the underwater work such as leveling can be reduced.

FIG. 9 shows a state in which the vicinity of the bottoms of the plurality of bag filling materials 1 are connected by the connecting rope 37. Connecting rope 37
The length of is determined in consideration of the interval between the bagging covering materials 1 after installation. The connection is possible on land and does not affect the installation method.
FIG. 9A is a diagram showing a state of being lifted up.
(B) is a figure which shows the installed state. Bagging dressing 1
By connecting with, the resistance will be crossed across the slip line after installation on the installation surface 39, so that the effect of reducing the earth pressure will be further increased.

FIG. 10 shows a cross-sectional view of a backfill structure according to the third embodiment of the present invention. An embankment made of the bagging and covering material 1 is installed at a position slightly away from the caisson 23. A backfill with a light embankment 41 is constructed between the embankment and the caisson 23. The earth pressure from the landfill material 25 is received by the embankment with the bagging and covering material 1. Earth pressure acting on the caisson 23 is light embankment 4
It is only earth pressure due to 1, and it is further reduced.

[0048]

As described above in detail, according to the present invention, it is possible to provide a backfilling structure and a backfilling construction method which achieve a reduction in earth pressure, have a filter effect, and enable a short construction period. You can

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a bag filling material 1.

FIG. 2 is a diagram showing types of mesh bags 3.

FIG. 3 is a diagram showing a standard manufacturing method of the bagging dressing 1.

FIG. 4 is a cross-sectional view of the backfill structure according to the first embodiment of the present invention.

FIG. 5 is a plan view showing a method of arranging the bag filling material 1 in layers.

FIG. 6 is a cross-sectional view of a backfill structure according to a second embodiment of the present invention.

FIG. 7 is a perspective view showing a means for installing a large number of bagging dressings 1.

FIG. 8 is a diagram showing a state of the bagging dressing material 1 suspended in a two-layer structure.

FIG. 9 is a view showing the bagging dressing 1 bonded together.

FIG. 10 is a sectional view of a backfill structure according to a third embodiment of the present invention.

FIG. 11 is a cross-sectional view of a conventional backfill structure.

[Explanation of symbols]

1 --------- Coating materials for bags 3 --------- mesh bag 5 --------- Filling material 7 --------- Hanging ring 11 --------- Production frame 13 --------- Backhoe 15 --------- Truck crane 21 --------- Foundation rubble 23 --------- Caisson 25 --------- Landfill 31 --------- Jig for hanging 33 --------- Hanging rope 35 --------- Auto release hook 37 --------- Connection rope 39 --------- Installation surface 41 --------- Lightweight embankment

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yoshikazu Ishikawa             1-13-20 Minamisenba, Chuo-ku, Osaka-shi, Osaka Prefecture               Within Kyowa Co., Ltd. (72) Inventor Satoshi Mase             1-13-20 Minamisenba, Chuo-ku, Osaka-shi, Osaka Prefecture               Within Kyowa Co., Ltd. (72) Inventor Takeshi Ikeya             Kashima-ken, 1-2-7 Moto-Akasaka, Minato-ku, Tokyo             Inside the corporation (72) Inventor Yoshinobu Akiyama             Kashima-ken, 1-2-7 Moto-Akasaka, Minato-ku, Tokyo             Inside the corporation (72) Inventor Kazuhide Tsumabuki             6-3-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Stocks             Within the company Tetra (72) Inventor Hirofumi Koyama             6-3-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo Stocks             Within the company Tetra F-term (reference) 2D018 BA12 CA02

Claims (10)

[Claims] 1. A back-filling structure comprising a plurality of coating materials filled with filling materials inside a mesh bag. 2. A mesh bag is formed by using a plurality of coating materials filled with a filling material, and a plurality of types of coating materials having different particle diameters of the filling material are installed in layers. Backfilling structure characterized by that. 3. At least two of the plurality of dressings.
3. The one according to claim 1, wherein the two are connected.
Backfilling structure described in. 4. An embankment having the backfilling structure according to claim 1 is provided behind a structure, and a lightweight embankment is provided between the structure and the embankment. Back-filling structure. 5. A method comprising: suspending a plurality of coating materials filled with a filling material inside a net bag on a hanging jig; and placing the coating materials at predetermined positions. Backfilling construction method characterized by. 6. The backfilling construction method according to claim 5, wherein an auto-release mechanism is provided between the covering material and the hanging jig. 7. The backfilling construction method according to claim 5, wherein the center spacing of the suspended coating material is substantially the same as the center spacing of the coating material after being installed. 8. At least two of said plurality of dressings.
The backfilling construction method according to any one of claims 5 to 7, wherein the two are connected. 9. The backfilling construction method according to claim 5, wherein there are a plurality of types of distances between the suspended covering material and the suspending jig. 10. The backfilling construction method according to claim 9, wherein a particle size of the filling material is different depending on the distance.