JP2013053427A - Reinforced soil wall construction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforced soil wall construction method capable of not only reducing a back surface distance of a retaining wall and reducing a construction cost but also securing a temporary greening part by securing a temporary greening part and planting plants that grow in a short period of time until the native plants (native species) are shifted.SOLUTION: A wall surface material 3 comprises a geocell 3 which is formed by joining a plurality of roughly belt-like belt members 5 at a prescribed interval and from which sediment restraining parts 7 for restraining sediment are formed by separating the non-joined parts of the belt members 5 from each other. A vegetation mat is fixed to the non-joined part in the plurality of belt members 3 positioned at the forefront row; a space surrounded by the belt members 5 and the vegetation mat is formed on a front surface of the geocell 3; and the space is filled with vegetation soil.

Description

  The present invention relates to a reinforced earth wall construction method and a wall surface material in which a retaining wall is formed by laminating wall materials, and the earth wall is reinforced by the retaining wall, and more particularly to a reinforced earth wall construction method suitable for wall greening.

  Conventionally, a reinforced earth wall construction method has been used in which a retaining wall is formed and reinforced on a dirt wall facing a road or a site. In this reinforced earth wall construction method, an anchor hole is drilled in embankment or cut, concrete is injected into this anchor hole, the tip of the tensile material is inserted into the concrete, and the upper end portion is led out from the anchor hole. A pressure receiving plate (wall surface material) formed of a concrete plate is fixed (for example, see Patent Document 1).

Japanese Patent No. 3556607 (pages 2, 3 and 1, 4 and 5)

  However, in the construction method described in Patent Document 1, since construction is performed using a heavy concrete pressure receiving plate (wall surface material), in order to ensure sufficient strength to restrain the heavy wall surface material. In addition, it is necessary to increase the thickness of the pressure plate (wall surface material) and to insert the tensile material deeply into the soil to increase the back surface distance of the retaining wall, which increases the construction cost.

  Moreover, when using concrete, since the soil used as a greening part is not sufficiently exposed due to the thickness of the pressure receiving plate (wall surface material), there is a problem in that the wall greening cannot be sufficiently performed and the appearance is poor. In particular, there are circumstances that require a period of about two to three years for the transition of native plants (natural species) that naturally invade, and wall greening between them is desired.

  The present invention has been made by paying attention to such problems, and not only can the back surface distance of the retaining wall be reduced to reduce the construction cost, but also until the native plant (a native species) transitions. Provides a reinforced earth wall construction method that can secure a temporary greening part until the native plant (local species) transitions by securing a temporary greening part and planting a plant that grows in a short period of time The purpose is to do.

In order to solve the above problems, the reinforced earth wall construction method of the present invention is:
Reinforced earth wall construction method in which wall materials are laminated to form a retaining wall, and the earth wall is reinforced by the retaining wall,
The wall surface material is formed by joining a plurality of substantially band-shaped band members at predetermined intervals, and a geocell capable of forming a sand-and-sand restraining portion for restraining the earth and sand by separating the non-bonded portions of the band members from each other. The vegetation mat is fixed to a non-joined portion of the plurality of belt members located in the front row, and a space surrounded by the belt member and the vegetation mat is formed on the front surface of the geocell, and earth and sand are placed in this space. It is characterized by embankment.
According to this feature, since the earth and sand are restrained by a geocell formed of a plurality of substantially strip-shaped strip members, the back surface distance of the retaining wall can be reduced, thereby reducing the construction cost of the retaining wall. Can be reduced. In addition, since the band member is composed of geocells, the structure is meandering at the front row of the band members. Therefore, by fixing the vegetation mat to non-joined parts of the band members, the band is formed on the front surface of the geocell. A space surrounded by the member and the vegetation mat can be formed. By embedding earth and sand in this space and planting a plant that grows in a short period of time, a temporary greening portion can be secured until the native plant (local species) transitions. In addition, since the earth and sand filled in the space surrounded by the vegetation mat described above is provided on the front surface of the band member, the surface of the band member is not exposed, the flow rate of rainwater is suppressed, and the earth is filled in the geocell. Can prevent the spilling of sediments.

Between the stacked geocells, sandwiching the front side of the geogrid formed of a substantially lattice-shaped sheet member, and burying the rear side of the geogrid in the embankment to form the retaining wall It is a feature.
According to this feature, the retaining wall is used to constrain the earth and sand with a geocell formed of a plurality of substantially band-shaped strip members, and to constrain the stacked state of the geocell using the load of the embankment by the geogrid. The back surface distance can be reduced, and the construction cost of the retaining wall can be reduced.

The reinforced earth wall construction method of the present invention is
A space surrounded by the strip member and the vegetation mat formed on the front surface of the geocell, where the earth and sand deposited in the geocell is subjected to a rolling compaction, and the earth and sand in the geocell is filled with high density. The earth and sand are filled at a density lower than that of the earth and sand in the geocell.
According to this feature, the earth and sand embanked in the geocell are subjected to a rolling compaction process, so that the strength of the retaining wall is increased and the outflow of the earth and sand is prevented. Will flow on the surface of the earth and sand embedding in the geocell located below with the passage of time, and the soil and sand in the geocell where the native plant (native species) transitions can be fertilized.

The reinforced earth wall construction method of the present invention is
The vegetation mat is a straw grass, and the surface of the straw grass is covered with a wire mesh, and the straw grass and the wire mesh are fixed to a non-joined portion of the belt member.
According to this feature, the space surrounded by the band member and the vegetation mat is sufficiently secured, and the straw and the wire nets corrode over time and naturally return, so that the native plant (native species) At the time of complete transition, the temporary greening portion will disappear.

The reinforced earth wall construction method of the present invention is
The stacked geocells are arranged such that at least a part of the earth and sand restraining portion of the geocell at the upper position covers the earth and sand restraining portion of the geocell at the lower position.
According to this feature, the geocells are connected to each other via the earth and sand in the earth and sand restraint portion of each geocell, and the strength of the retaining wall can be improved, and the belt member and the vegetation mat are surrounded by the misalignment of both. The earth and sand in the remaining space easily flows on the earth and sand surface embanked in the geocell located below as time elapses.

The reinforced earth wall construction method of the present invention is
A minute uneven portion is formed on the surface of the band member of the geocell.
According to this feature, the minute uneven portions can not only improve the frictional force between the earth and sand in the earth and sand restraint portion and improve the strength of the retaining wall, but also are surrounded by the belt member and the vegetation mat. It is possible to improve the frictional force between the earth and sand in the open space and prevent the earth and sand from flowing out quickly.

3 is a cross-sectional view showing a retaining wall in Example 1. FIG. It is a perspective view which shows a geocell. It is a perspective view which shows the state which the geocell laminated | stacked. It is sectional drawing which shows the state by which the straw turf plant was vegetated. It is sectional drawing which shows the state which the plant of the native species changed. It is an expanded sectional view which shows the unevenness | corrugation and through-hole which were provided in the strip | belt member. It is sectional drawing which shows the state in which the straw turf plant in Example 2 was vegetated. It is a perspective view which shows the geocell in Example 3. FIG.

  EMBODIMENT OF THE INVENTION The form for implementing the reinforced earth wall method which concerns on this invention is demonstrated below based on an Example.

  The reinforced earth wall construction method according to Example 1 will be described with reference to FIGS. Hereinafter, the left side of FIG. 1 and FIG. 4 will be described as the front side (front side) of the retaining wall, and the lower left side of FIG. 2 and FIG. 3 will be described as the front side (front side) of the retaining wall.

  Reference numeral 1 in FIG. 1 denotes a retaining wall to which the present invention is applied. The retaining wall 1 is formed so as to cover the entire front surface of the earth wall 2 facing a road or a site. The retaining wall 1 is constructed using a geocell 3 as a wall material of the present invention that forms a wall surface of the retaining wall 1 and a geogrid 4 as a reinforcing material.

  Further, a straw grass 20 and a wire mesh 21 are fixed to the front surface (front surface) of the geocell 3. The straw turf 20 is a vegetation mat according to the present invention. The straw turf 20 has thin cotton and plant seeds attached to the surface of the straw that is formed in a saddle shape. This plant species is a species of plants such as turf that grows in a short period of time, and after the completion of construction, the straw turf plant grows on the surface of the straw turf 20 in a short period (about 2 to 3 months). Yes.

  As shown in FIG. 2, the geocell 3 is composed of a plurality of substantially band-shaped band members 5 formed of a flexible material such as synthetic resin. In the present embodiment, six belt members 5 are provided in the front-rear direction, these belt members 5 are arranged so that the width direction thereof is perpendicular, and in a state where the belt members 5 are arranged in a stacked manner, They are joined at predetermined intervals in the longitudinal direction. This joining portion is a welded portion 6 (crimped portion) that is welded (or crimped) while applying pressure.

  When the geocell 3 is expanded in the front-rear direction, the sand-and-sand restraining portion 7 that restrains the sand and sand can be formed by separating the non-joined portions of the belt members 5 from each other. This earth and sand restraint part 7 is arranged in a staggered or honeycomb shape. In this earth and sand restraint part 7, earth and sand are put and compacted by a rolling process (see FIG. 3), and can be formed into a thick plate-like layered structure by geocell 3 and earth and sand.

  As shown in FIG. 2, the straw grass 20 is arranged so as to be sandwiched between the wire mesh 21 and the front row of the geocell 3, and the straw grass 20 and the wire mesh 21 are not in the plurality of belt members 5 positioned in the front row of the geocell 3. It is fixed to the joining portion by a staple 22. Thus, the space 23 surrounded by the straw turf 20 and the belt member 5 is formed on the front side of the geocell 3 by the fixing of the straw turf, and the soil 23 is filled in the space 23 to plant the straw turf plant that grows in a short time. Thus, a temporary greening portion can be secured until the native plant (local species) transitions (see FIG. 4).

  Further, since the belt member 5 is formed of a material such as a synthetic resin, there is a possibility that rain water in the rain may flow rapidly on the surface of the belt member 5. 20, since the earth and sand embanked in the wire mesh 21 and the space 23 are provided, the surface of the belt member 5 is not exposed, the flow rate of rainwater is suppressed, and the earth and sand embanked in the geocell 3 are prevented from flowing out immediately. be able to.

  In addition, as the straw turf 20 and the wire mesh 21 corrode with time and return spontaneously, the temporary greening part disappears at the time when the native plant (the native species) has completely transitioned (Fig. 5). At this time, the vegetation mat is not limited to the straw turf 20 but may be, for example, a coconut fiber or a biodegradable plastic thread.

  A plurality of small through-holes 8 are formed in the belt member 5 of the geocell 3, and the mutual sediment restraint portions 7 communicate with each other through the through-holes 8. In addition, since the through-hole 8 is not formed in the strip | belt member 5 located in the front row | line | column of the geocell 3, the earth and sand in the earth and sand restraint part 7 do not flow out, Therefore ) And the temporary greening portion are arranged separately from each other in the geocell 3 where the transition is), and greening is possible for a long period without mutual interference.

  In addition, the earth and sand embanked in the geocell 3 is subjected to a rolling compaction process, and the earth and sand is embanked at a high density, and is surrounded by a belt member 5 and a straw lawn 20 formed on the front surface of the geocell 3. The earth and sand in 23 is filled with a density lower than the earth and sand in the geocell 3 at least. According to this, the strength of the earth and sand embanked in the geocell 3 is increased by the rolling process, and the outflow of the earth and sand is prevented, and the earth and sand in the space 23 is embanked in the geocell 3 located below as time passes. It is possible to fertilize the earth and sand in the geocell 3 where the native plant (native species) transitions.

  As shown in FIG. 3, when construction is performed, the geocell 3 is laminated together with the earth and sand while the earth and sand are put into the earth and sand restraining portion 7 of the geocell 3. Further, the stacked geocells 3 are arranged such that at least a part of the earth and sand restraining portion 7 of the geocell 3 at the upper position covers the earth and sand restraining portion 7 of the geocell 3 at the lower position.

  As shown in FIG. 1, in the present embodiment, a plurality of earth and sand restraint portions 7 are formed in the front-rear direction of each geocell 3, and the earth and sand restraint portion 7 in the forefront of the geocell 3 in the lower position is formed on the geocell 3 in the upper position. An area of approximately half of the foremost soil restraint part 7 is covered. In this way, the geocells 3 are connected to each other via the earth and sand in the earth and sand restraining portion 7 of each geocell 3, and the strength of the retaining wall 1 can be improved. Furthermore, due to the misalignment, the earth and sand in the space 23 surrounded by the belt member 5 and the straw grass 20 can easily flow over the earth and sand surface that is embanked in the geocell 3 positioned below as time elapses.

  In addition, in the earth and sand restraint part 7 of the geocell 3, since the same plant 11 which inhabits in the earth and sand collected at the construction site is vegetated, a native species comes to grow naturally in the earth and sand restraint part 7 of the geocell 3 . After the construction, when a predetermined period elapses, the roots 12 of the plants 11 grown in the earth and sand restraint portion 7 of the geocell 3 enter the through holes 8 of the band member 5 (see FIG. 6) and become entangled with the band member 5. . And the root 12 of the plant 11 entangled with the belt member 5 extends deep into the soil.

  Moreover, as shown in FIG. 6, the embossing is given to the surface of the strip | belt member 5 of the geocell 3, and the fine uneven | corrugated | grooved part 13 (emboss) is formed. The minute uneven portions 13 can improve the frictional force between the earth and sand in the earth and sand restraining portion 7 and the geocell 3 and improve the strength of the retaining wall 1. Furthermore, earth and sand enter the through hole 8 of the band member 5, and this through hole 8 improves the frictional force between the earth and sand in the earth and sand restraining part 7 and the geocell 3, and the strength of the retaining wall 1. Can be improved. In addition, the frictional force between the earth and sand in the space 23 and the surface of the geocell 3 can be improved to prevent the earth and sand from flowing out immediately.

  Thus, since the wall surface material of the retaining wall 1 is the geocell 3 formed of a plurality of substantially band-shaped band members 5, the wall surface material is reduced in weight and can be easily transported, and the wall surface material is lightweight. Even if it becomes the geocell 3, it becomes possible to keep the strength of the retaining wall 1 sufficiently by restraining the earth and sand to the earth and sand restraining part 7 of the geocell 3 and restrain the embankment 9 by the lightened geocell 3. In order to restrain the stacked state of the geocell 3 using the load of the embankment 9 by the geogrid 4 while forming the wall surface, the back surface distance L (see FIG. 1) from the wall surface of the retaining wall 1 to the earth wall 2 is set. It becomes possible to make it small, and the construction cost of the retaining wall 1 can be reduced. In addition, since the back surface distance L of the retaining wall 1 is small, it is not necessary to dig deeply in front of the earth wall 2 which is the formation object of the retaining wall 1, and a construction period can also be shortened. In addition, since the construction can be performed by sandwiching the front side of the geogrid 4 formed of a sheet member having a substantially lattice shape between the stacked geocells 3, the connection work between the geocell 3 and the geogrid 4 is performed. It becomes possible to carry out without using a separate connecting member such as a connecting anchor, and the construction work is simplified.

  Next, a reinforced earth wall construction method according to Example 2 will be described with reference to FIG. In addition, the same structure as the said Example and the overlapping structure are abbreviate | omitted.

  As shown in FIG. 7, the straw grass 201 (vegetation mat) is configured to be higher than the height of the geocell 3 and covers the earth and sand restraint portion 7 of the geocell 3 and the space 23 on the front side of the geocell 3.

  According to this, since the space 23 is covered with the straw grass 201, the earth and sand portion of the space 23 is not exposed, and the appearance can be maintained. Further, since the straw grass 201 is configured to be higher than the height of the geocell 3, the rain grass 201 can suppress rainwater flowing on the surface of the space 23 when heavy rain falls, and can prevent the earth and sand from flowing out quickly.

  Next, a reinforced earth wall construction method according to Example 3 will be described with reference to FIG. In addition, the same structure as the said Example and the overlapping structure are abbreviate | omitted.

  As shown in FIG. 8, unlike the first embodiment, the geocell 3 can be installed in the opposite direction. In this case, the through hole 8 is installed so as to face the front side of the geocell 3.

  According to Example 3, the roots (not shown) of the plant 11 planted in the space 23 and the grass 23 can be extended to the earth and sand in the geocell 3 through the through-holes 8. Growth can be promoted.

  Although the embodiments of the present invention have been described with reference to the drawings, the specific configuration is not limited to these embodiments, and modifications and additions within the scope of the present invention are included in the present invention. It is.

  For example, in the above-described embodiment, by putting the earth and sand collected at the construction site into the earth and sand restraint part 7 of the geocell 3, the native species of the plants 11 that inhabit the earth and sand are within the earth and sand restraint part 7 of the geocell 3. Although it is designed to grow naturally, the plant 11 that grows spontaneously in the sediment control part 7 is not limited to the native species, and may be other species, particularly a plant that is entangled with the front side of the geocell 3 such as coral. Also good.

  Moreover, in the said Example, although the geogrid 4 as a reinforcing material is used, the geogrid 4 does not necessarily need to be used, for example, the retaining wall 1 is comprised only by the geocell 3, the straw grass 20, and the wire mesh 21. May be constructed.

1 Retaining wall 2 Earth wall 3 Geocell (wall material)
4 Geogrid (reinforcing material)
5 Belt member 6 Welding part 7 Sediment-restraint part 8 Through hole 9 Filling 11 Plant 12 Root 13 Concavity and convexity part 20 Straw grass (vegetation mat)
21 Wire mesh 22 Staple 23 Space

Claims (6)

Reinforced earth wall construction method in which wall materials are laminated to form a retaining wall, and the earth wall is reinforced by the retaining wall,
The wall surface material is formed by joining a plurality of substantially band-shaped band members at predetermined intervals, and a geocell capable of forming a sand-and-sand restraining portion for restraining the earth and sand by separating the non-bonded portions of the band members from each other. The vegetation mat is fixed to a non-joined portion of the plurality of belt members located in the front row, and a space surrounded by the belt member and the vegetation mat is formed on the front surface of the geocell, and earth and sand are placed in this space. Reinforced earth wall construction method characterized by embankment.   Between the stacked geocells, sandwiching the front side of the geogrid formed of a substantially lattice-shaped sheet member, and burying the rear side of the geogrid in the embankment to form the retaining wall The reinforced earth wall construction method according to claim 1, wherein   A space surrounded by the strip member and the vegetation mat formed on the front surface of the geocell, where the earth and sand deposited in the geocell is subjected to a rolling compaction, and the earth and sand in the geocell is filled with high density. The reinforced earth wall construction method according to claim 1 or 2, wherein the earth and sand is filled with at least a lower density than the earth and sand in the geocell.   The vegetation mat is straw grass, and the surface of the straw grass is covered with a wire mesh, and the straw grass and the wire mesh are fixed to a non-joined portion of the belt member. The reinforced earth wall construction method described in Crab.   5. The stacked geocell is arranged such that at least a part of the earth and sand restraint portion of the geocell at the upper position is covered with the earth and sand restraint portion of the geocell at the lower position. The reinforced earth wall construction method described.   6. The reinforced earth wall construction method according to claim 1, wherein minute uneven portions are formed on a surface of the band member of the geocell.

Images