JPH0799022B2 - Reinforced soil structure snout - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforced soil structure in which a metal mesh such as a metal grit is used as a slope protection material for protecting the slope of an embankment layer.

[0002]

2. Description of the Related Art Conventionally, the problems to be solved by the invention
As a reinforced soil structure of this kind, concrete panels and U
It is generally known that a V-shaped metal plate is installed as a slope protection material for an embankment layer, and a concrete panel or a U-shaped metal plate is connected to a reinforcing material for fixing the metal plate in the embankment layer. ing.

By the way, in recent years, from the standpoint of landscape conservation for civil engineering structures, these greening have been desired, but there is a problem that the above-mentioned known structures cannot perform greening.

Further, the latter one using the concrete panel has a problem that the concrete panel is heavy and the workability is extremely poor.

Reinforced earth structures using a synthetic resin net as a slope protection material and a reinforcement material are also known.
Since the synthetic resin net is soft and easy to stretch, it is largely deformed, and since there is no self-sustaining force, it is almost impossible to construct a reinforced soil structure with little deformation, and there is a risk that it will sometimes collapse.

In particular, the lack of self-sustaining force causes a problem of workability, and it is difficult to keep the slope surface portion in a specific shape, and the sandbag is caught to fix the end portion of the net in the embankment. Such a conventional method requires a large amount of human power, and labor saving and mechanization of the construction are impossible.

Further, according to the research by the present inventor, the reason why the reinforced soil retaining wall of the geotextile using sandbags is easily deformed is not only the elongation of the geotextile, but the sandbag is easily deformed. Loose soil on the back may also result in overall deformation.

Further, a method of using a metal mesh as a slope protection material has also been proposed, but in the conventional method, a plate-shaped member is welded to the end of the expanded metal and the plate-shaped member is screwed with a bolt. However, since they are constructed by connecting them, the structure is complicated, and if bolting at the site is insufficient, they are easily destroyed by earth pressure, and there are problems such as difficult work management. Further, this method has a problem that the wall surface is deformed as the embankment is performed, and the deformation cannot be adjusted.

Further, since the expanded metal has a mesh structure in which the tensile member is positioned obliquely with respect to the direction in which the load acts, there is a problem in that the expanded metal is likely to be displaced with respect to a rolling load or earth pressure. .

Therefore, even if the expanded metal wall member and the geotextile are combined, both of them have large deformations, so that workability is poor and deformation of the embankment is large.

A reinforced earth work method is also known in which a reinforcing bar grit obtained by welding longitudinal reinforcing bars and transverse reinforcing bars together is used as a reinforcing material. However, this method has a large rigidity of the reinforcing bar grit. It is possible to construct a reinforced soil retaining wall with less expansion of the reinforcement material and less displacement, and because the resistance of many reinforcing bars in the lateral direction against the earth pressure acting on the wall surface is large, embankment soil with low frictional force Is excellent in that it can be used as.

However, since the rigidity of the reinforcing bar grit is large, the bending stress applied to the lateral reinforcing bars becomes large. Therefore, it is necessary to reduce the longitudinal reinforcing bar spacing to reduce the bending stress of the lateral reinforcing bars. Absent.

For this reason, there arises a problem that the number of reinforcing bars in the longitudinal direction must be greater than or equal to the number necessary for the earth pressure applied to the wall surface.

Further, since the reinforcing bar has high rigidity, there is a problem that stress concentration is likely to occur near the siding surface inside the embankment.

Further, there is a problem of workability and a problem of transportability that the shape and length cannot be arbitrarily changed according to the ground at the site.

The present invention has been made to solve the above problems, and provides a rational reinforced soil structure which is easy to construct and can hold the embankment layer extremely stably. With the goal.

[0017]

In order to solve the above-mentioned problems, the reinforced soil structure according to the present invention uses a reinforcing bar grit having a large bending rigidity in the vicinity of the surface of the embankment to restrain the independence and the soil on the surface. Then, they are integrated to form a block-shaped soil mass that does not loosen, and a geotextile that is easily deformable is used in the deep part of the embankment.

That is, in the reinforced soil structure according to the first aspect of the present invention, the metal mesh composed of the vertical rebars and the horizontal rebars is arranged vertically on the slope of the embankment layer, and The upper and lower metal meshes are connected by a connecting pin, the vertical reinforcing bars of the metal mesh are bent into an approximately L shape to form legs of the metal mesh, and the legs are embedded in the embankment layer, and , A plurality of deformable geotextiles are embedded in the embankment layer, and the ends thereof are connected to the metal mesh.

Further, the laying length of geotextile and the shape of installation can be adjusted by arbitrarily cutting or connecting at the site according to the required fixing length and terrain conditions.

In the reinforced earth structure according to the second or third aspect of the present invention, in the reinforced earth structure, a connecting pin for connecting metal meshes that are vertically arranged to the vertical reinforcing bar is inserted. By forming a possible recess or ring, stacking the upper and lower metal meshes with the recess or ring protruding from the mesh of the upper metal mesh, and inserting the connecting pin into the recess or ring. , The upper and lower metal meshes are connected to each other.

In the above, "concave" means "convex"
Even if the “protrusion” is expressed as “rush”, the difference is the expression whether the metal mesh is viewed from the front side or the back side, which is exactly the same in the present invention.

According to a fourth aspect of the present invention, in the reinforced soil structure according to the second aspect, in the reinforced soil structure according to the second aspect, the embankment near the legs of the metal mesh is replaced by the legs of the metal mesh. By pouring from the mesh, it is possible to perform construction without worrying about displacement when pouring soil on the back surface of the surface member.

[0023]

EXAMPLES Example 1. 1 to 5 show an embodiment of a reinforced soil structure according to the present invention, in which reference numeral 1 denotes a metal mesh for protecting a slope 2a of an embankment layer 2, and 3 denotes the metal mesh 1. A mesh sheet is shown as an example of a geotextile that is fixed in the embankment layer 2 and stably holds the embankment layer 2. Further, reference numeral 4 is a connecting pin for connecting the upper and lower metal meshes 1, 1 A connecting pin for connecting the left and right metal meshes 1, 1 and a connecting pin 6 for connecting the mesh sheet 3 to the metal mesh 1.

In the metal mesh 1, a plurality of vertical reinforcing bars 1a and horizontal reinforcing bars 1b are arranged in a grid pattern, and the intersections of the vertical reinforcing bars 1a and the horizontal reinforcing bars 1b are welded to be integrally connected. And, the vertical rebar 1a is almost L in the embankment 2.
Bending into a letter shape to form the leg portion 1c of the rebar net,
It is configured by forming a concave portion (or a convex portion) 1d for inserting the connecting pin 4 near the upper end of the vertical reinforcing bar 1a and a ring 1e for inserting the connecting pin 5 at both ends of the horizontal reinforcing bar 1b. (See FIG. 2). In the above, the ring 1e and the connecting pin 5 are not always necessary.

In FIG. 2, the horizontal reinforcing bar 1b located above the recess 1d is not always necessary.

A ring 1 through which a connecting pin 4 can be inserted instead of the recess 1d formed near the upper end of the vertical reinforcing bar 1a.
f may be formed (see FIGS. 6A and 6B).

The diameters and pitches of the vertical reinforcing bars 1a and the horizontal reinforcing bars 1b are appropriately determined according to the scale of the reinforced soil structure.

The size of the mesh between the vertical reinforcing bars 1a and the horizontal reinforcing bars 1b needs to be such that at least the leg portions 1c can be easily filled with the embankment from between them. For that purpose, the pitch of the vertical reinforcing bar 1a and the horizontal reinforcing bar 1b is 3
It is desirable that it is not less than centimeters, preferably not less than 5 centimeters.

The concave (or convex) portion 1d is formed by bending the upper end of the vertical reinforcing bar 1a into a U shape on the side of the embankment layer 2 (see FIG. 3 (a)) or (see FIG. 3 (b)). The ring 1f is formed by bending the end portion of the vertical reinforcing bar 1a into a circular shape, and the ring 1e is formed by bending the end portion of the horizontal reinforcing bar 1b into a circular shape.

The metal mesh 1 is installed while being connected to each other in the vertical and horizontal directions. Among these, the upper and lower metal meshes 1 and 1 are attached to the lower end of the vertical reinforcing bar 1a of the upper metal mesh 1 to form the lower metal. The upper end portion of the vertical reinforcing bar 1a of the mesh 1 made has a concave portion (or convex portion) 1d from the mesh of the upper metal mesh 1 to the embankment layer 2 side (see FIG. 3 (a)), or the outside of the embankment layer 2 (see FIG. 3 ( (See FIG. 3 b), and the connecting pin 4 is attached to the concave portion (or convex portion) 1 d horizontally so as to be rotatably coupled (see FIG. 3).

When the upper and lower metal meshes 1, 1 having the ring 1f instead of the recess 1d are connected, the ring 1f is protruded from the mesh of the upper metal mesh 1 to the embankment side in the same manner as described above. The connecting pin 4 is inserted into 1f (see FIGS. 6A and 6B).

Further, the left and right metal meshes 1 and 1 are formed by superposing the rings 1e and 1e formed at the ends of the horizontal reinforcing bars 1b and 1b and inserting the connecting pin 5 into the rings 1e and 1e. It is rotatably connected (see FIG. 5).

The left and right metal meshes may be simply superposed on each other at the ends, or may be superposed on each other and tied together by a binding wire. In addition, a sheet 7 for preventing soil outflow, in which seeds for vegetation are planted, is attached to the inside of the metal mesh 1 as needed, thereby achieving greening. It should be noted that greening can be achieved by omitting the sediment outflow prevention sheet 7 and planting seeds directly on the slope 2a of the embankment layer 2, but in this case, the metal mesh 1 is used to prevent sediment from flowing out. The smaller one shall be used.

Mesh sheet 3 which is a geotextile
Is buried in the embankment layer 2 in the same plane as the leg portion 1c of the metal mesh 1 while rolling strongly. In addition, the end portion of the mesh sheet 3 is the leg portion 1c of the metal mesh 1.
Is attached to the leg portion 1c, protrudes above the mesh of the leg portion 1c, and is connected by inserting the connecting pin 6 into the protruding portion (see FIG. 4).

Rainwater can permeate the mesh sheet 3,
A corrosion-resistant and deformable mesh sheet that is hard to rot, has good compatibility with the embankment layer 2, and is easy to roll is used. For example, a synthetic resin mesh sheet such as a vinyl mesh sheet is used. ing.

Example 2. 7 to 9 show another embodiment of the reinforced soil structure according to the present invention, in which the surface of the metal mesh 1 for protecting the slope 2a of the embankment layer 2 is vertically formed. Other configurations are almost the same as in Example 1, but the order of construction using a metal mesh having a ring provided at the upper end is shown.

The reinforced soil structure according to the above invention is shown in FIG.
It is constructed by the construction procedure shown in (a), (b) and (c).

First, in FIG. 7 (a), the metal mesh 1 is made to stand on the ground horizontally with the legs 1c being horizontal, and the mesh sheet 3 is connected horizontally to the ground as a reinforcing member, and further, A sheet 7 for preventing sediment loss with seeds attached is attached to the inside of the metal mesh 1.

Next, the earth and sand 8 are placed on the mesh sheet 3.
And then compacted to form the embankment layer 2b. In this case, the metal mesh 1 is self-supporting due to its rigidity and shape.

Next, as shown in FIG.
7 (a) on the embankment layer 2a, which was embankd by (a).
The above operation is repeated to form the embankment layer 2c.

The vertically adjacent metal meshes 1, 1 are
The ring 1f formed on the lower metal mesh 1 is inserted between the meshes of the leg mesh of the upper metal mesh 1 and the connecting pin 4 is inserted into the ring 1f to connect them (FIG. 7). (B)).

To connect the ends of the mesh sheet 3 placed on the embankment layer 2b, the upper and lower metal meshes 1, 1
The connecting pin 4 used for the connection of the above is also used, and the connecting pin 4 is inserted into the ring 1f to connect the end portion of the mesh sheet 3 to the leg portion 1c of the metal mesh 1. Make the mesh made upright.

Next, embankment is laid on the mesh sheet 3 to form an embankment layer 2c, so that the mesh sheet 3 is fixed.

Next, as shown in FIG. 7 (c), the embankment is put into the leg of the lower metal mesh 1 from the mesh of the leg 1c of the upper metal mesh 1 and compacted.

With this construction method, the upper part of the metal mesh 1 on the entire lower surface is fixed by the leg portion 1c of the upper metal mesh 1, and the leg portion 1c of the upper metal mesh 1 is fixed.
And the mesh sheet 3 is fixed on the upper embankment layer,
Moreover, since the embankment layer is introduced from between the meshes of the metal mesh 1 of the leg portion 1c of the upper metal mesh 1, it can be maintained despite the compaction of the embankment.

FIG. 8 is a completed view of the reinforced soil structure, and FIG. 9 shows an example of a metal mesh used in the reinforced soil structure shown in FIG. 8, in which a recess 1 is formed near the upper end of the vertical reinforcing bar 1a.
d is formed, and a leg portion 1c bent at a right angle is formed at the lower end portion.

The surface of the reinforced soil structure thus constructed can be covered with mortar to form a temporary embankment.

If it is formed on the back of the existing concrete retaining wall, earth pressure does not act on the retaining wall. Moreover, after constructing the reinforced soil structure according to the present invention, it is possible to construct a concrete retaining wall on the front surface and fill mortar between them to achieve integration. In this case, since the earth pressure hardly acts on the concrete retaining wall, the cross section of the retaining wall can be made small or can be covered with a simple concrete panel or a vegetation block.

In the present invention, lightweight embankments such as foamed mortar, foamed urethane, foamed blocks and solidified soil may be used as the embankment layer.

Example 3. 10 and 11 show a third embodiment of the reinforced soil structure according to the present invention. In the drawings, reference numeral 9 is a metal mesh for protecting the slope of the embankment layer 2.

The metal mesh 9 has a plurality of vertical rebars 9a and horizontal rebars 9b arranged in a grid pattern, and is integrally connected by welding the intersections of the vertical rebars 9a and horizontal rebars 9b. And, the upper and lower end portions of the vertical reinforcing bar 9a are bent in the embankment layer 2 in a substantially inverted L shape to form leg portions 9c and 9c, and further, the tip end portion of the leg portion 9c and both end portions of the horizontal reinforcing bar 9b. Ring 9d for inserting the connecting pins 4 and 5 into
(Fig. 11)
reference).

The diameters and pitches of the vertical reinforcing bars 9a and the horizontal reinforcing bars 9b are appropriately determined according to the scale of the reinforced soil structure and the like. The ring 9d is formed by bending the ends of the vertical reinforcing bar 9a and the horizontal reinforcing bar 9b into a circular shape.

The metal mesh 9 is installed while being connected to each other in the vertical and horizontal directions. Of these, the upper and lower metal meshes 9 and 9 are rings 9 formed at the ends of the legs 9c.
They are rotatably connected by superimposing d and 9d and continuously inserting the connecting pin 4 into the rings 9d and 9d.

The left and right metal meshes 9 and 9 are rotatable by overlapping the rings 9d and 9d formed at the ends of the horizontal reinforcing bar 9b and inserting the connecting pin 5 into the rings 9d and 9d. Are linked to.

Since the other structure is almost the same as that of the first embodiment, in the figure, the same parts as those of the first embodiment and the corresponding parts are designated by the same reference numerals and the description thereof is omitted.

[0056]

As described above, according to the reinforced soil structure according to the present invention, since a plurality of metal meshes are installed as slope protection materials on the slope of the embankment layer, the conventional concrete structure is used. Unlike panels, it is much lighter, easier to handle, and has excellent workability.

Further, greening can be easily carried out by, for example, installing a soil and sand outflow prevention sheet in which seeds for vegetation are planted inside the metal mesh.

Since the upper and lower metal meshes are rotatably connected by the connecting pins, the shape of the slope can be adjusted during construction, and the predetermined slope and leg can be bent. By using a metal mesh having an angle, it is possible to easily construct a slope having an arbitrary shape.

If adjacent metal meshes are connected to each other by inserting a connecting pin into a ring or a recess, it is much easier to connect the metal meshes to each other as compared with the connection method by bolting. It can respond to terrain conditions.

Further, each metal mesh is laid and fixed around the slide surface of the embankment by geotextile, and the reinforcing material of the geotextile is a mesh sheet or a non-woven fabric made of synthetic resin, and a plurality of layers are formed in the embankment. It is buried and has good compatibility with the embankment, so the embankment can be carefully compacted so that the metal mesh can be securely fixed on the slope and the embankment can be kept in an extremely stable state. be able to.

Further, the workability at the site is excellent, and it is possible to work according to the topographical conditions. Moreover, in the work with abdomen, the geotextile is fixed to the slope with anchors so that the slope can be easily ablated without excavating the slope. The embankment can be constructed.

In the reinforced earth method, a large stress is generated in the reinforcing material near the siding surface and the displacement of the embankment layer is large. Therefore, when a metal reinforcing material having high rigidity is laid in this area, a large stress is easily generated, and In the metal mesh, the bending stress in the lateral direction becomes large as described above, and the interval between the vertical reinforcing bars is narrowed more than the required tension to increase the number.

However, according to the present invention, since the geotextile which is easily adapted to the displacement around the siding surface is laid, the geotextile is integrated with the embankment without causing stress concentration, and the vertical direction of the metal mesh is close to the slope. Due to the existence of the horizontal reinforcing bars overlaid on the reinforcing bars, the earth pressure on the slope member and the lateral pressure due to the rolling pressure are reduced, so that the displacement of the slope surface is reduced.

Further, the embankment material can be put in between the shape of the vertical rebar being bent in an L shape and the mesh of the metal mesh, and the earth pressure acts in the direction of the vertical rebar so that the reinforcing bar mesh is formed. It is not easily deformed, and the vertical reinforcing bars and horizontal reinforcing bars welded together to form L-shaped ones combined vertically have large bending rigidity and those filled with soil have horizontal reinforcing bars. The soil is firmly blocked by the restraint effect of.

For this reason, the compaction of the embankment on the back portion is facilitated, and the slope is less likely to be deformed during or after construction.

Also, the mesh sheet can be connected to the metal mesh very easily by penetrating the end portion of the mesh sheet in the mesh of the metal mesh and inserting the connecting pin into the penetrating portion of the mesh sheet. .

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view of an embodiment of a reinforced soil structure according to the present invention.

2 is a partial schematic perspective view of a metal mesh used in the reinforced soil structure of FIG. 1. FIG.

3 (a) and 3 (b) are partial vertical cross-sectional views showing a structure of a connecting portion of upper and lower metal meshes in the reinforced soil structure of FIG.

FIG. 4 is a partial vertical cross-sectional view showing a structure of a mesh sheet connecting portion in the reinforced soil structure of FIG. 1.

5 is a partial plan view showing the structure of the left and right metal mesh connecting portions in the reinforced soil structure of FIG. 1. FIG.

6 (a) and 6 (b) are partial longitudinal sectional views showing a construction method of another embodiment of the reinforced soil structure according to the present invention.

7 (a), (b) and (c) are partial vertical cross-sectional views showing a construction method of another embodiment of a reinforced soil structure according to the present invention, and FIG. It is a partial cross section figure which shows the structure of a connection part.

FIG. 8 is a partial vertical cross-sectional view of a reinforced soil structure.

FIG. 9 is a partial schematic perspective view of a metal mesh used in the reinforced soil structure snout of FIG.

FIG. 10 is a partial vertical cross-sectional view of another embodiment of the reinforced soil structure according to the present invention.

11 is a partial schematic perspective view of a metal mesh used in the reinforced soil structure of FIG.

[Explanation of symbols]

1 ... Metal mesh, 2 ... Embankment, 3 ... Mesh sheet,
4, 5, 6 ... Connection pin, 7 ... Sheet for preventing sediment outflow, 8
… Metal mesh, 9… Metal mesh.

Claims (4)

[Claims] 1. A metal mesh composed of vertical rebars and horizontal rebars is installed vertically on the slope of the embankment layer, and the upper and lower metal meshes are connected by connecting pins.
A vertical rebar of the metal mesh is bent into an approximately L shape to form a leg portion of the metal mesh, the leg portion is embedded in the embankment layer, and a deformable geotextile is embedded in the embankment layer. A reinforced earth structure which is embedded in a plurality of layers and whose end portions are connected to the leg portions of the metal mesh. 2. A vertical reinforcing bar is formed with a recess into which a connecting pin for connecting upper and lower metal meshes can be inserted, and the upper and lower metal meshes are formed so that the recesses protrude from the mesh of the upper metal mesh. The reinforced earth structure according to claim 1, wherein metal meshes that are vertically adjacent to each other are connected by overlapping and inserting the connecting pin into the recess. 3. A vertical reinforcing bar is formed with a ring into which a connecting pin for connecting upper and lower metal meshes can be inserted, and the upper and lower metal meshes are placed in a state of protruding from the mesh of the upper metal mesh. The reinforced earth structure according to claim 1, wherein metal meshes that are vertically adjacent to each other are connected by overlapping and inserting the connecting pin into the ring. 4. The embankment in the vicinity of the legs of the metal mesh is introduced from the mesh of the legs of the metal mesh to claim 1, 2, or 3. Reinforced earth structure.