JPH09268580A - Construction method of retaining wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to eliminate the need for a disassembling work of a form after the placement of concrete and enhance the outward appearance or strength of a retaining wall. SOLUTION: An embedded weir plate 2 is erected on a base part of foundation concrete 33 of a retaining wall on the natural ground side while a decorated weir plate 3 is erected on the foundation concrete 33 at the opposed position separated with a specified spacing from the embedded weir plate 2. The space between the embedded weir plate 2 and the decorated weir plate 3, which are erected as opposed, is connected with a connecting metal fitting 4, thereby constructing a concrete placement form 1 where concrete is placed in the form. PC embedded panels 10 are laid out every where on the upper and lower and right and left areas on the embedded weir plate 2 while each of the PC embedded panels 10 is connected with a connecting metal fitting 13. Decorated panels 15 are continuously laid out on the decorated weir plate 3 every where on the upper and lower and right and left areas white each decorated panel 15 is connected with a connecting reinforcing bar 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a retaining wall for preventing the collapse of soil such as steep slopes of natural ground due to cut soil or embankment.

[0002]

2. Description of the Related Art In some cases, a steep slope of a natural ground formed by cutting or embankment may be provided with a retaining wall made of concrete or the like in order to prevent the slope from collapsing. Conventionally, when the above retaining wall is provided, basic concrete is placed in advance along the slope of the natural ground, and two dam plates are arranged at predetermined intervals (within the width of the retaining wall to be formed) on the basic concrete portion. It is formed by placing concrete on the molds that are spaced apart (corresponding intervals). At the time of molding the mold, a separator is provided between the opposing barrier plates so that the barrier plates are kept at a predetermined distance. A hydraulic jack or the like having an adjustable length is laid between the dam plate surface and the slope on the slope side of the ground to support the formwork so as not to fall until the cast concrete is hardened. After constructing the retaining wall, backfill the retaining wall with earth and sand.

[0003]

However, the above-mentioned conventional formwork is troublesome because it needs to be dismantled after the concrete is hardened. In addition, many of the dismantled molds are disposed of as waste materials, which is not preferable while the reduction of waste is required. Furthermore, it is required to improve work efficiency and accuracy for work that requires a lot of skill and is manually performed by a worker, such as formwork. Therefore, the method for constructing the retaining wall of the present invention is to form a form by connecting the embedded weir plate and the decorative weir plate with connecting fittings, and without disassembling the form frame after concrete placement, An object of the present invention is to provide a method for constructing a retaining wall that can easily and surely connect decorative barrier plates. Moreover, it aims at providing the construction method of a retaining wall which can improve the aesthetics and strength of a retaining wall.

[0004]

The method for constructing a retaining wall of the present invention has solved the above-mentioned problems, and a retaining wall made of concrete is constructed along the slope of a natural ground to prevent the collapse of sediment. It is a construction method, in which the PC embedding panels having screw holes at appropriate positions on the concrete placing surface are continuously arranged vertically and horizontally, and the embedding dam plate in which each PC embedding panel is connected by a connecting member and the makeup on the surface A decorative panel with a pattern and screw holes at appropriate positions on the back is arranged vertically and horizontally, and at the same time, it is made to face the decorative barrier plate in which each decorative panel is connected by a connecting member, and the decorative barrier plate is embedded. Both ends of the connecting metal fittings are screwed into the screw holes with the weir plate to connect both weir plates, and concrete is placed between the decorative weir plate and the embedded weir plate to connect the decorative weir plate and the embedded weir plate. Placed concrete An integral in the killing buried, with building a high strength retaining wall, and so mold dismantling of concrete after casting becomes unnecessary.

Further, the connecting metal fitting for connecting the embedded weir plate and the decorative weir plate is elastically deformed into a substantially V-shaped cross section, and a thin steel plate provided with elongated holes at symmetrical positions with respect to the bending line, and an outer end. Is composed of a decorative dam plate and two connecting rods screwed into the screw holes of the embedded dam plate, and two long holes of a thin steel plate in which the inner end sides of the two connecting rods are bent into a substantially V-shaped cross section. It is inserted into the base and the two connecting rods are crimped by the elastic force of the thin steel plate so that the connecting work between the embedded dam plate and the decorative dam plate can be easily performed. A first drainage pipe that is provided with a mouth and is inclined downward from each drainage port toward the middle of the thickness of the retaining wall is provided, and the tip of each first drainage pipe is placed between the embedded weir plate and the decorative weir plate. Connect any position of the to one end of the reinforcement pipe arranged from the top to the bottom, The lower end of the strong pipe is connected to the rear end of the second drainage pipe that inclines downward from the lower portion between the embedded barrier plate and the decorative barrier plate toward the lower part of the decorative barrier plate, and the first drainage pipe and the second drainage pipe are connected. By connecting the pipes through the reinforcing pipes, the water that accumulates on the back of the retaining wall can be drained, or the lower ends of the embedded weir plate and decorative weir plate are fixed to the reinforcing bars for basic concrete for concrete placement. The strength of the formwork was improved.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a retaining wall construction method of the present invention will be described with reference to FIGS. The concrete pouring formwork 1 for a retaining wall for constructing a concrete retaining wall constructed on the slope of the natural ground provided by cutting and embankment,
The embedded weir plate 2 is erected at the base of the retaining wall foundation concrete 33 on the side of the natural ground, and the foundation concrete 33 at the opposite position is separated from the embedded weir plate 2 by a predetermined distance.
The makeup barrier plate 3 is erected on the upper side, and the embedded barrier plate 2 and the makeup barrier plate 3 which are erected oppositely are connected by a connecting fitting 4. Further, the lower ends of the embedded dam plate 2 and the decorative dam plate 3 are connected to the reinforcing bars for the basic concrete,
Inner rebar with lower end connected to rebar for foundation concrete 3
4 are arranged along the vertical direction between the embedded weir plate 2 and the decorative weir plate 3.

As shown in FIG. 2, the foundation concrete 33
In the embedding dam plate 2 erected at the base on the natural ground side, for example, PC embedding panels 10 formed of concrete in a substantially rectangular shape are arranged vertically and horizontally, and
The PC-embedded panels 10 are connected to each other by connecting rebars 13 arranged vertically as connecting members.
The PC-embedded panels 10 are arranged so that the end portions of the PC-embedded panels 10 arranged at the upper and lower positions are offset from each other so that the PC-embedded panels 10 can be firmly connected to each other. In addition, the lower end of the connecting reinforcing bar 13 connecting the respective PC embedding panels 10 is fixed to the reinforcing bar for the basic concrete by welding or the like so that the embedding dam plate 2 is connected to the reinforcing bar
It is fixed to the foundation concrete 33 through 3. The PC-embedded panel 10 can be formed of one kind selected from concrete, resin concrete, FRP, and GRC, and is molded in advance in a factory or the like to improve dimensional accuracy. It should be noted that the shape of the PC-embedded panel 10 is not limited to the substantially rectangular shape, but may be formed in a substantially H shape or the like.

As shown in FIG. 3, a PC embedded panel 10 is provided.
Two pairs of fixing fittings 12 each having a curved reinforcing bar holding portion are provided on the upper and lower opposite edges of the back surface of the so that the connecting reinforcing bar 13 can be held by the reinforcing bar holding portion. The fixing metal fittings 12 are the fixing metal fittings 1 of each PC embedding panel 10 when the PC embedding panels 10 are continuously arranged vertically and horizontally.
The mounting positions are adjusted so that the two are arranged in a straight line along the up-down direction, and the connecting rebars 13 arranged along the up-down direction are attached to the fixing brackets 12 of the PC-embedded panel 10.
Each PC embedding panel 10 can be connected by locking with.

On the surface of the PC-embedded panel 10 on the concrete pouring side, a recess 1 for reducing the weight of the PC-embedded panel 10 is formed.
0a is provided. In addition, the insert 1 in which a thread groove is provided on the inner peripheral surface at an appropriate position on the bottom of the recess 10a
1 is embedded and fixed to form a screw hole, and an end portion of a connecting rod of a connecting metal fitting 4 described later is screwed into the connecting metal fitting 4
The end of the can be locked quickly. Note that the screw hole may be directly provided at an appropriate position on the bottom of the recess 10 a of the PC-embedded panel 10 without providing the insert 11. On the opposite side surfaces of the PC-embedded panel 10, a connecting protrusion 10b and a fitting groove 10c into which the connecting protrusion 10b is fitted are provided.
Each PC when the embedded dam plate 2 is constructed with the embedded panel 10.
The embedded panel 10 can be strongly connected.

The decorative barrier 3 which is isolated from the embedded barrier 2 for a predetermined period of time and stands up on the foundation concrete 33 on the side opposite to the slope side of the ground is provided with a decorative pattern such as an uneven pattern on the surface. The decorative panels 15 formed of concrete in a substantially rectangular shape are continuously arranged vertically and horizontally, and the decorative panels 15 are connected to each other by connecting rebars 18 arranged vertically as connecting members. The decorative panel 15 is the PC-embedded panel 10.
Similarly, by arranging the decorative panels 15 arranged at the upper and lower positions with their ends displaced, the decorative panels 15 can be firmly connected. Further, the lower end of the connecting reinforcing bar 18 connecting the decorative panels 15 is fixed to the reinforcing bar for the basic concrete by welding or the like, and the decorative dam plate 3 is fixed to the basic concrete 33 via the connecting reinforcing bar 18.

The decorative panel 15 can be made of a single layer selected from concrete, resin concrete, FRP and GRC, and in addition to the above, 2
The strength of the panel can be improved by forming it in multiple layers using at least one kind of material, and the dimensional accuracy can be improved by molding in advance in a factory or the like. Furthermore, it is possible to improve the aesthetics of the retaining wall constructed by coloring the uneven pattern or the like provided on the surface of the decorative panel so as to be a surface finish as it is. It should be noted that the shape of the decorative panel 15 is not limited to the substantially rectangular shape, but may be formed in a substantially H shape.

As shown in FIG. 4, two pairs of fixing metal fittings 17 having curved reinforcing bar holding portions are provided at the upper and lower opposite edges of the back surface of the decorative panel 15, as in the PC embedded panel 10. The connecting bar 18 can be held by the reinforcing bar holding portion. The fixing bracket 17 is the PC embedded panel 1
Like the fixing bracket 12 of 0, the fixing bracket 17 of each decorative panel 15 is arranged in a straight line along the vertical direction,
Each connecting panel 15 can be connected by locking the connecting reinforcing bar 18 with a fixing member 17.

A concave portion 15a for reducing the weight of the decorative panel 15 is provided on the back surface of the decorative panel 15 (surface on the concrete pouring side).
Is provided. Further, at an appropriate position on the bottom of the recess 15a, an insert 16 having a thread groove on its inner peripheral surface is formed.
Is embedded and fixed to form a screw hole, and the end of the connecting rod of the connecting fitting 4 described later can be screwed in to quickly lock the end of the connecting fitting 4.
Similar to the PC-embedded panel 10, screw holes may be directly provided at the bottom of the recess 15a. On the opposite side surfaces of the decorative panel 15, the connection protrusion 15b and the connection protrusion 1 are provided.
A fitting groove 15c for fitting the 5b is provided so that each decorative panel 15 can be strongly connected when the decorative barrier plate 3 is constructed with a plurality of decorative panels 15. Note that P
Insert 11 of C-embedded panel 10 and decorative panel 15
The insertion position of the insert 16 is adjusted so that the insert 16 can be opposed to each other when the panels are assembled.

As shown in FIG. 5, the connecting metal fitting 4 connecting the embedded weir plate 2 and the decorative weir plate 3 has, for example, two connecting rods 20 and 21 using long round rods, whose inner ends are substantially in cross section. Inserted into the two long holes 22a of the thin steel plate 22 bent in a V shape,
The elastic force of the thin steel plate 22 presses the two connecting rods 20 and 21 together. This connecting fitting 4 includes two connecting rods 20,
The PC embedded panel 10 has an outer end 21 formed on a screw portion.
It is possible to screw it into the inserts 11 and 16 of the decorative panel 15, so that both dam plates can be reliably connected and held at a predetermined interval. In addition, in order to adjust the length of the connecting rod, an extension rod may be provided at the end of each connecting rod via a joint (for example, a crimp joint). Further, the connecting rod 21 is cut from the middle so that the inclination angle of the two connecting rods 20, 21, the embedded weir plate 2 and the decorative weir plate 3 can be easily coped with, and the cut portion is passed through a ball joint or the like. They may be connected, and in this case, the end of the connecting rod can be screwed in a direction perpendicular to the surface of the embedding / decorating panel on the concrete pouring side.

In addition to the above, as shown in FIG. 6, the first drainage pipe, the reinforcing pipe, and the second drainage pipe are provided on the concrete pouring formwork 1.
A drainage pipe may be provided to drain water accumulated on the back of the retaining wall. Specifically, a drainage port 40 is provided at an appropriate position of a predetermined PC embedding panel 10 ′ of the embedding dam plate 2, and each drainage port 40 is located between the embedding dam plate 2 and the makeup dam plate 3. A first drainage pipe 41 is provided which is inclined downward toward the distance.
A filter 41a for preventing sediment inflow is provided at the rear end of the first drainage pipe 41 so that clogging in the pipe can be prevented. In addition, PC embedded panel 1
A filter 41a may be provided on the 0'drainage port 40.

The tip of each first drainage pipe 41 is connected to one end of a reinforcing pipe 42 which is disposed at an arbitrary position between the embedded weir plate 2 and the decorative weir plate 3 from the top to the bottom so as to guide the drainage. The water on the back surface of the retaining wall is designed to flow into the drainage pipe 42 via the first drainage pipe 41. FIG.
As shown in (b), the reinforcing pipes 42 arranged between the two dam plates are composed of a plurality of reinforcing pipes 42 through a joint 44.
The compartments are connected and communicate with each other in a substantially rhombic lattice shape, and several points at appropriate positions on the upper portion of the lattice-shaped reinforcing pipe 42 and the tip of the first drainage pipe 41 are connected via a joint 44 so that the angle can be adjusted. . Then, the second drainage pipe 4 in which several points at appropriate positions on the lower end of the grid-shaped reinforcing pipe 42 are inclined downward from the lower portion between the both dam plates toward the lower part of the decorative dam plate 3.
The third drainage pipe 41 and the second drainage pipe 43 are connected to each other through a joint 44 at the rear end of the retaining pipe 3 so that the first drainage pipe 41 and the second drainage pipe 43 communicate with each other, and water collected on the back surface of the retaining wall is retained. It is designed so that water can be drained from the lower front of the. By the way, a predetermined decorative panel 15 ′ of the decorative panels 15 arranged below the decorative barrier plate 3 is provided with a hole 45 for arranging the tip of the second drainage pipe 43 at an appropriate position. 2 The water can be drained from the tip of the drainage pipe 43 to the front of the retaining wall.

The above-mentioned first drainage pipe 41 and reinforcing pipe 4
The second and second drainage pipes 43 are each made of metal or synthetic resin that is resistant to rust. The upper part of the grid-shaped reinforcing pipe 42 is connected to the first drainage pipe 41 and the lower part of the reinforcing pipe 42 is connected to the second drainage pipe 43. Both drainage pipes and the reinforcing pipes are embedded in concrete. The strength of the retaining wall can be improved. Further, the reinforcing pipe 42 is not limited to the substantially rhombic lattice, and the first drain pipe and the second drain pipe are connected to both ends of a single reinforcing pipe, or the first and second drain pipes and the reinforcing pipe are connected to each other. It may be configured with one pipe. If the reinforcing pipes are formed in a grid pattern, the number of the second drainage pipes can be made smaller than that of the first drainage pipes, and the number of holes on the surface of the retaining wall can be reduced, which is preferable in view of landscape. Become.

In order to construct a retaining wall using the embedded barrier plate 2, the decorative barrier plate 3 and the connecting metal fittings 4 having the above-mentioned constitution, each embedded panel 10 is provided at the base of the foundation concrete 33 of the retaining wall on the slope side of the natural ground. And the embedding dam plate 2 in which the embedding panels 10 are connected by the connecting rebars 13 arranged in the up-and-down direction. On the basic concrete 33 spaced apart from the embedded dam plate 2 by a predetermined distance, the internal reinforcing bars 34 are laid out so as to be connected to the reinforcing bars for the basic concrete to form a structural body of the retaining wall. In addition, on the opposite side of the internal rebar 34 from the embedded dam plate 2, each decorative panel 15 is continuously arranged vertically and horizontally on the basic concrete 33 at a position opposed to the internal rebar 34 with a predetermined interval therebetween. The decorative barrier plate 3 in which the decorative panel 15 is connected by the connecting rebars 18 arranged in the vertical direction is erected.

In the case of providing drainage, the rear end of the first drainage pipe 41 is connected to each of the plurality of drainage ports 40 provided in the embedded weir plate 2, and the middle of the thickness of the retaining wall is changed from the top to the bottom. The reinforcing pipes 42 are connected to each other in a generally rhombic lattice shape toward each other, and the tips of the first drainage pipes 41 are connected to the upper portions of the reinforcing pipes. The second portion is arranged so as to incline downward from the lower portion of the retaining wall toward the front of the lower portion of the retaining wall.
The rear end of the drainage pipe 43 and the lower portion of the reinforcing pipe 42 are connected to each other, and the tip of the second drainage pipe is connected to the hole 45 of the decorative panel 15 '.
Connect to. In addition, the reinforcing pipe 42 and the like are connected to the internal rebar 3
It does not matter even if it is locked to 4.

Then, the outer end of the connecting fitting 4 is locked between the PC-embedded panel 10 of the embedding dam plate 2 and the facing inserts 11 and 16 of each decorative panel 15 of the embossment dam plate 3, and the embedding dam plate 2 is embedded. The decorative dam plate 3 is connected and held at a predetermined interval, and the concrete placing formwork 1 for the retaining wall is constructed along the slope of the natural ground 30. In this formwork, the lower ends of the embedded weir plate 2 and the decorative weir plate 3 are fixed to the reinforcing bars for the basic concrete to have high strength, and the retaining wall to be constructed can be made strong.

In order to connect both dam plates with the connecting fitting 4, the both ends of the thin steel plate 22 are grasped and the thin steel plate 22 is bent into a substantially V shape, and the crimping of the connecting rods 20 and 21 is loosened to connect the two. Stick 2
The space between 0 and 21 is adjusted so that the outer ends of the connecting rods 20 and 21 are inserted into the PC-embedded panel 10 and the decorative panel 15.
The thin steel plate 22 is returned to the original position after being screwed and fixed to 1, 16 and the connecting rods 20 and 21 are pressure-bonded to connect and hold the decorative dam plate 3 and the embedded dam plate 2 at a predetermined interval. Against the lateral pressure of concrete. At this time, since the outer ends of the connecting rods 20 and 21 of the connecting metal fitting 4 are screwed to the inserts 11 and 16 of both panels, the embedded weir plate 2 and the decorative weir plate 3 are surely connected to each other. It can be self-supporting on the basic concrete 33, and can be a strong concrete casting formwork 1. After connecting the two dam plates with the connecting metal fitting 4, the appropriate positions of the connecting rods 20 and 21 of the connecting metal fitting 4 and the appropriate positions of the internal rebars 34 arranged between the two dam plates are fixed by welding or the like. The cover thickness of the internal rebar 34 may be ensured and the strength of the concrete pouring formwork 1 may be improved. After constructing the concrete casting formwork 1 for the retaining wall, concrete is placed between the embedded weir plate 2 and the decorative weir plate 3, and when the placed concrete hardens, the retaining wall is completed. After the retaining wall is completed, the back of the retaining wall will be backfilled with earth and sand.

The cast concrete is the embedded dam plate 2
Around the connecting rebars 13 and 18 of the and the decorative barrier plate 3, and the recesses 10a and 15a of the PC embedding panel 10 and the decorative panel 15 respectively.
The concrete that has entered and is strongly integrated with the decorative dam plate 3 and the embedded dam plate 2 is strongly integrated, and the decorative dam plate 3 and the embedded dam plate 2 are strongly integrated.
Can be the structural body of the retaining wall. Further, since both the dam plates are buried, it is not necessary to dismantle the formwork after constructing the retaining wall. The basic concrete may be applied first, or may be applied by placing concrete simultaneously with the concrete placing formwork 1 for the retaining wall. Further, when the basic concrete and the retaining wall are simultaneously constructed, the embedded dam plate 2 and the decorative dam plate 3 are fixed to the reinforcing bar for the basic concrete 33 via the connecting reinforcing bar. The above retaining wall is provided along the slope of the ground that is cut or filled, but in addition, it should be erected at any place as a vertical structure such as a fence, wall, or weir. But it doesn't matter. At this time, if the back surface of the retaining wall is not filled with earth and sand, do not provide a drainage pipe for draining water.

[0023]

According to the method of constructing a retaining wall of the present invention, the embedded dam plate and the decorative dam plate can be easily and surely connected by the connecting metal fittings, so that the strength of the concrete placing formwork is improved. Moreover, it is not necessary to dismantle the formwork after placing concrete, and it is possible to reduce the construction period and cost. Further, since the dismantling work of the formwork is not performed and the waste material accompanying it is not generated, the cost required for the waste treatment is not required and the waste can be reduced.
Moreover, if the water accumulated on the back surface of the retaining wall is drained through the first drain pipe, the reinforcing pipe, and the second drain pipe,
Since water is drained to the lower part of the front surface of the retaining wall, a plurality of drainage holes do not appear on the entire front surface of the retaining wall, which is preferable in view of landscape. Further, the lower ends of both dam plates can be fixed to the reinforcing bars for the basic concrete to construct a stronger retaining wall.

[Brief description of drawings]

FIG. 1 is an explanatory side view showing an embodiment of a retaining wall construction method of the present invention.

FIG. 2 is a front view showing a buried dam plate.

FIG. 3 is an explanatory plan view (a) showing the embedded panel, and FIG.
It is an AA arrow line view of (a), and a side explanatory view (c) of an embedding panel.

FIG. 4 is an explanatory plan view (a) showing a decorative panel, and FIG.
It is the BB arrow line view (b) of (a), and the side surface explanatory drawing (c) of a decorative panel.

FIG. 5 is an explanatory plan view (a) showing a coupling fitting and a side explanatory view (b).

FIG. 6 is a side explanatory view (a) showing a case where a drainage pipe is provided in the retaining wall, and a front explanatory view (b) of the reinforcing pipes embedded in the retaining wall and connected in a grid pattern.

[Explanation of symbols]

 1 Concrete formwork 2 Embedded dam plate 3 Decorative dam plate 4 Connecting fitting 10 PC embedding panel 15 Decorative panel 40 Drainage port 41 First drainage pipe 42 Reinforcement pipe 43 Second drainage pipe

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shigenobu Tanaka 2-14-14 Shin-Yokohama, Kohoku-ku, Yokohama-shi, Kanagawa Toyoko Giken Co., Ltd. (72) Seiichi Maruyama 35-1 Kishine-cho, Kohoku-ku, Yokohama-shi, Kanagawa Inside the coral

Claims (4)

[Claims] 1. A construction method for constructing a concrete retaining wall along a slope or the like of a ground to prevent the collapse of earth and sand, which comprises precast concrete embedding having screw holes at appropriate positions on a concrete placing surface. Panels (hereinafter referred to as PC embedding panels) are arranged vertically and horizontally, and the embedding dam plate is formed by connecting each PC embedding panel with a connecting member, and the surface is decorated with screw holes at appropriate positions on the back surface. The decorative panels are arranged vertically and horizontally, and at the same time, the decorative barriers in which the decorative panels are connected by connecting members are made to face each other at a predetermined interval, and both ends of the connecting metal fittings are screwed into the decorative barriers and the embedded barriers. Connect both weir plates by screwing, place concrete between the decorative weir plate and the embedded weir plate, and use it to embed the decorative weir plate and embedded weir plate in the cast concrete. Retaining wall method of construction which is characterized in that an integral Te. 2. A connecting metal member for connecting the embedded barrier plate and the decorative barrier plate is a thin steel plate elastically deformed into a substantially V-shaped cross section and provided with elongated holes at symmetrical positions with respect to the bending line. The outer end is composed of a decorative weir plate and two connecting rods screwed into the screw holes of the embedded weir plate, and the inner end sides of the two connecting rods are two thin steel plates bent in a substantially V-shaped cross section. The method for constructing a retaining wall according to claim 1, wherein the two connecting rods are inserted into the long holes and crimped by the elastic force of the thin steel plate. 3. A drainage port is provided at a plurality of positions on the embedded weir plate, and a first drainage pipe is provided which inclines downward from each drainage port toward the middle in the thickness direction of the retaining wall. The tip of the pipe is connected to one end of a reinforcing pipe arranged so that the arbitrary position between the embedded weir plate and the decorative weir plate faces from top to bottom, and the lower end of each reinforcing pipe is connected to the embedded weir plate and the decorative weir plate. It is connected to the rear end of the second drainage pipe that inclines downward from the lower part between the plate and the lower part of the decorative dam plate, and the first drainage pipe and the second drainage pipe are connected through a reinforcing pipe. The method for constructing a retaining wall according to claim 1 or 2, wherein. 4. The method of constructing a retaining wall according to claim 1, wherein the embedded dam plate and the decorative dam plate are fixed at their lower ends to a reinforcing bar for basic concrete.