JP7511303B1 - Retaining wall - Google Patents

Abstract

A retaining wall is provided that reinforces the strength of the surface of a wall member and can reliably support the horizontal component of earth pressure for a long period of time.
[Solution] The retaining wall 1 of the present invention comprises a wall head 4a, a wall foot 4b and a wall main body 4c of a wall member 4. The wall head 4a and the wall foot 4b are formed at the upper and lower ends of the portion of the exposed H-shaped steel 6 corresponding to the wall member 4, and the H-shaped steel 6, the channel steel 3, the horizontal reinforcing bars 7a and the vertical reinforcing bars 7b are embedded in the wall head 4a and the wall foot 4b with concrete. The wall main body 4c is formed as the wall member 4 integrally with the wall head 4a and the wall foot 4b, and is formed between the upper and lower ends of the portion of the exposed H-shaped steel 6 corresponding to the wall member 4. The channel steel 3, the horizontal reinforcing bars 7a and the vertical reinforcing bars 7 are embedded in the wall main body 4c with concrete.
[Selected figure] Figure 3

Description

The present invention relates to retaining walls.

A retaining wall is a wall-like structure designed and constructed to resist lateral soil pressure and prevent slope collapse when a large elevation difference is required in the ground that exceeds the angle of repose of the soil.
Patent Document 1 proposes a retaining wall that reduces as little as possible the amount of flat land for constructing a building. This retaining wall will be described with reference to Figs. 13 and 14.

As shown in FIG. 13, the retaining wall 100 includes multiple support piles 20. The support piles 20 include a columnar portion 50 formed from cement milk in the ground, and an H-shaped steel 60 whose lower portion is disposed inside the columnar portion 50 and whose upper portion is exposed from the columnar portion 50.

As shown in FIG. 14, the retaining wall 100 also includes a channel steel 30 fixed to the H-shaped steel 60 by welding or the like. The channel steel 30 is a shaped steel that includes a web 30a, a first flange 30b formed on one end of the web 30a, and a second flange 30c formed on the other end of the web 30a.

Furthermore, the retaining wall 100 includes a wall member 40. The wall member 40 is formed of so-called reinforced concrete in which reinforcing bars 70 are embedded in concrete.
The reinforcing bars 70 are made up of reinforcing bars 70a extending horizontally and arranged on the web 30a of the channel steel 30, and reinforcing bars 70b extending vertically.
The wall member 40 is disposed in a planar (plate-like) shape along the H-shaped steel 60 of the plurality of support piles 20, and is fixed to the support piles 20 via channel steel 30 embedded therein. In the retaining wall 100, the planar wall member 40 is configured to receive the horizontal component of earth pressure.

In this way, the retaining wall 100 has a composite structure in which the support piles 20 and the wall members 40 are integrated by embedding the channel steel 30, horizontal reinforcing bars 70a, and vertical reinforcing bars 70b in the wall members 40 and fixing the wall members 40 to the support piles 20 via the channel steel 30.
The wall member 40 receives the horizontal component of the earth pressure. This horizontal component of the earth pressure is transmitted to the H-shaped steel 60 at the upper part of the support pile 20 via the channel steel 30, and then to the lower part of the support pile 20. The wall member 40 resists the lateral pressure of the soil and prevents the collapse of the slope.

Patent No. 6940709

According to the retaining wall 100 proposed in Patent Document 1, support piles 20 are installed vertically and planar (plate-shaped) wall members 40 are formed along the support piles 20, thereby preventing the collapse of the slope by resisting the lateral pressure of the soil.
However, in the retaining wall 100 proposed in Patent Document 1, the wall member 40 is made of so-called reinforced concrete, and therefore the strength of the wall member 40 is not sufficient, and there is a risk of distortion due to earth pressure, destruction such as shear failure, collapse, and sinking.In addition, since the wall member 40 is formed in a planar (plate-like) shape, there is a risk of heaping and consolidation sliding occurring.

In addition, in the retaining wall 100 proposed in Patent Document 1, the first flange 30b of the channel steel 30 is fixed to the H-shaped steel 60 by welding or the like. Then, whether the channel steel 30 is fixed to the H-shaped steel 60 is confirmed by an impact inspection.
However, when a hammer is applied to the second flange 30c of the channel steel 30 to perform an impact inspection, the hammer may move sideways when it hits the tip of the second flange 30c. This may cause a danger to the worker, as the hammer may move sideways and hit the worker.

Furthermore, the wall member 40 of the retaining wall 100 proposed in Patent Document 1 is formed in a single plane (plate shape).
Therefore, for example, in the case where the land on which a building is to be constructed has slopes X and Y in two adjacent directions as shown in FIG. 15, in the retaining wall 100 proposed in Patent Document 1, it was necessary to form wall members 40X and 40Y separately on the slopes in the two directions.
In other words, since the wall member 40 is formed as separate wall members 40X, 40Y and fixed to separate support piles 20X, 20Y, there was a problem that greater strength could not be obtained compared to when the wall members were connected to each other and integrated.

The present invention was made in consideration of the above circumstances, and aims to provide a retaining wall that has greater strength in the wall members and can reliably support the horizontal component of earth pressure for a long period of time.

In order to solve the above-mentioned problems, the retaining wall according to the present invention is a retaining wall that receives the horizontal component of earth pressure by means of wall members, and includes a plurality of support piles having a columnar portion formed of cement milk in the ground and an H-shaped steel whose lower portion is disposed inside the columnar portion and whose upper portion is exposed from the columnar portion, a plurality of channel steels fixed to the outer and inner sides of the upper and lower ends of the portion of the H-shaped steel that corresponds to the wall member, and fixed to the outer side between the upper and lower ends of the portion of the H-shaped steel that corresponds to the wall member, horizontal reinforcing bars arranged on the upper surface of the channel steel and extending laterally, and the H-shaped steel. The wall is characterized by having a vertical reinforcing bar arranged along the axis of the steel and extending vertically, a wall head and wall foot formed at the upper and lower ends of the part of the H-shaped steel that corresponds to the wall member, in which the H-shaped steel, the channel steel, the horizontal reinforcing bar, and the vertical reinforcing bar are embedded inside with concrete, and a wall body formed as the wall member integrally with the wall head and wall foot, and between the upper and lower ends of the part of the H-shaped steel that corresponds to the wall member, the channel steel, the horizontal reinforcing bar, and the vertical reinforcing bar are embedded inside with concrete.

With this configuration, the wall body of the wall member is made of so-called reinforced concrete (RC structure), in which channel steel, horizontal reinforcing bars, and vertical reinforcing bars are embedded inside the concrete. Furthermore, the wall head and wall foot formed above and below the wall body of the wall member are SRC structures in which H-shaped steel, channel steel, and reinforcing bars are embedded in concrete, and function as a strong beam structure. This significantly improves the strength of the wall member, and makes it possible to suppress distortion due to earth pressure, destruction such as shear failure, collapse, and subsidence of the wall member.

In this way, the retaining wall of the present invention can increase the strength of the wall members, allowing them to reliably support the horizontal component of earth pressure for a long period of time.

Here, it is preferable that the wall head and wall foot are shaped to protrude inward from the wall main body, the wall head is formed to have a greater widthwise length than the wall main body, and the wall foot is formed to have a greater widthwise length than the wall main body.
As described above, at the top and base of the wall, the channel steel is fixed to the outer and inner sides of the H-shaped steel, and at the main body of the wall, the channel steel is fixed to the outer side of the H-shaped steel.
Therefore, the length of the wall head and wall foot in the width direction (front-to-back direction of the wall) is greater than the thickness of the wall body of the wall member. That is, the wall head and wall foot are shaped to protrude inward from the wall body of the wall member. In particular, the lower surface of the wall foot of the wall member has a surface shape (bottom shape) that is greater in length in the width direction (front-to-back direction of the wall) than the thickness of the wall body of the wall member, which makes it possible to more effectively prevent the occurrence of settlement, heaping, and consolidation slippage.

Furthermore, it is preferable that the wall head and the wall foot further include first stirrups arranged at each of the upper and lower ends so as to surround the horizontal reinforcing bars arranged in channel steel fixed to the outer and inner sides of the upper and lower ends of the part of the H-shaped steel corresponding to the wall member, and that the H-shaped steel, the channel steel, the horizontal reinforcing bars, the vertical reinforcing bars and the first stirrups formed at the upper and lower ends of the part of the H-shaped steel corresponding to the wall member are embedded inside with concrete.
In this way, by providing the first stirrups, the strength of the wall member is further improved, and the occurrence of damage such as distortion and shear failure due to earth pressure in the wall member can be further suppressed.

It is also preferable that the channel steel is an angle steel, one side of the angle steel is joined to an H-shaped steel, and the angle steel is attached to the H-shaped steel in an L-shape when viewed from the side.
In this way, since the angle steel is attached to the H-shaped steel in an L-shape in side view, it is easy to arrange the horizontal reinforcing bars on the upper surface of the channel steel. Also, when the channel steel is an angle steel and the angle steel is attached to the H-shaped steel in an L-shape, the second flange of the channel steel does not protrude as shown in Patent Document 1, so that it is easy to hit the channel steel with a hammer during impact inspection, and it is possible to avoid the danger of the hammer hitting the tip of the second flange, drifting laterally, and hitting a worker.

It is also preferable that at least two of the channel steels are provided in the vertical direction on the outer and inner sides of the upper and lower ends of the part of the H-shaped steel that corresponds to the wall member, and that first stirrups are provided on each of the upper and lower ends so as to surround the horizontal reinforcing bars arranged in the at least two channel steels fixed to the outer and inner sides of the upper and lower ends of the part of the H-shaped steel that corresponds to the wall member.
In this way, at least two of the channel steels are provided in the vertical direction on the outer and inner sides of the upper and lower ends, respectively, and the first stirrup is provided to surround the entire horizontal reinforcing bars arranged in the channel steels, thereby further improving the strength of the upper end (wall head) and the lower end (wall foot) of the wall member.

Furthermore, it is preferable that the first stirrups are provided in a plurality at a predetermined interval between the H-shaped steel bars, and that if the first stirrups are provided adjacent to the vertical reinforcing bars, the first stirrups are tied to the vertical reinforcing bars and the horizontal reinforcing bars, and if the first stirrups are not provided adjacent to the vertical reinforcing bars, the first stirrups are tied to the horizontal reinforcing bars and width stop bars tied to the horizontal reinforcing bars arranged above and below.
With this configuration, the strength of the upper end portion (wall head portion) and the lower end portion (wall foot portion) of the wall member can be further improved.

It is also preferable that second stirrups are provided at the upper end and the lower end, respectively, facing the outer surface of the H-shaped steel and surrounding the entire horizontal reinforcing bars arranged in the channel steel fixed to the outer surface of the H-shaped steel, and that third stirrups are provided at the upper end and the lower end, respectively, facing the inner surface of the H-shaped steel and surrounding the entire horizontal reinforcing bars arranged in the channel steel fixed to the inner surface of the H-shaped steel.
With this configuration, the strength of the upper end portion (wall head portion) and the lower end portion (wall foot portion) of the wall member can be further improved.

Moreover, it is preferable that the second stirrup and the third stirrup are each provided in a plurality at a predetermined interval facing the H-shaped steel, and when the second stirrup and the third stirrup are provided close to the vertical reinforcing bars, the second stirrup and the third stirrup are tied to the vertical reinforcing bars and the horizontal reinforcing bars, and when the second stirrup and the third stirrup are not provided in contact with the vertical reinforcing bars, the second stirrup and the third stirrup are tied to the horizontal reinforcing bars.
With this configuration, the strength of the upper end portion (wall head portion) and the lower end portion (wall foot portion) of the wall member can be further improved.

In addition, a plurality of the wall members each having a linear shape in a plan view may be provided, and the plurality of wall members may be connected at a predetermined intersecting angle to form an integrated wall member.
In this way, when a plurality of the wall members are connected at a predetermined cross angle and formed as an integrated wall member, greater strength can be obtained compared to when the wall members are formed as separate wall members.
In addition, a connecting member may be provided at the wall head for connecting the H-shaped steel beams constituting the support piles to each other.

The present invention provides a retaining wall that has greater strength in the wall members and can reliably support the horizontal component of earth pressure for a long period of time.

FIG. 1 is a front view of a retaining wall according to a first embodiment of the present invention. FIG. 2 is a plan view of the retaining wall of FIG. FIG. 3 is a partial cross-sectional view showing an upper part of the II cross section of FIG. FIG. 4 is a partial cross-sectional view showing the lower part of the II section in FIG. FIG. 5 is a partial cross-sectional view showing an upper part of the II-II cross section of FIG. FIG. 6 shows a first stirrup. FIG. 7(a) shows the second stirrup and (b) shows the third stirrup. FIG. 8 is a diagram showing width restricting stripes. FIG. 9 is a plan view of a retaining wall according to a second embodiment of the present invention. FIG. 10 is a front view of a retaining wall according to a third embodiment of the present invention. FIG. 11 is a partial cross-sectional view of a retaining wall according to a third embodiment, corresponding to FIG. FIG. 12 is a partial cross-sectional view of a retaining wall according to a third embodiment, corresponding to FIG. FIG. 13 is a front view of a conventional retaining wall. FIG. 14 is a cross-sectional view showing a portion of the retaining wall of FIG. FIG. 15 is a plan view showing the case where the retaining wall of FIG. 13 is provided on slopes in two directions.

(First embodiment)
Hereinafter, an embodiment of a retaining wall according to the present invention will be described with reference to the drawings. Fig. 1 is a front view of a retaining wall according to a first embodiment of the present invention, and Fig. 2 is a plan view of the retaining wall of Fig. 1. Fig. 3 is a partial cross-sectional view of an upper part of the retaining wall taken along section II of Fig. 2, and Fig. 4 is a partial cross-sectional view of a lower part of the retaining wall taken along section II of Fig. 2. Fig. 5 is a partial cross-sectional view of an upper part of the retaining wall taken along section II-II of Fig. 2.
It should be noted that the drawings show one embodiment of the retaining wall structure, and the spacing and number of reinforcing bars can be changed as appropriate, and the present invention is not limited to this embodiment.

(Schematic configuration of retaining wall 1)
As shown in Figures 1 to 4, a retaining wall 1 comprises support piles 2, a channel steel 3, and a wall member 4. The retaining wall 1 according to the present invention is characterized in that a wall head portion 4a and a wall foot portion 4b are provided above and below a wall main body portion 4c of the wall member 4, as shown in Figure 1.

As shown in Figures 3 and 4, channel steel 3 is provided at the wall head portion 4a and the wall foot portion 4b. The channel steel 3 is fixed to the outer and inner surfaces of the upper end portion (wall head portion 4a) and lower end portion (wall foot portion 4b) of the portion of the H-shaped steel 6 that corresponds to the wall member 4. The channel steel 3 is also provided on the outer surface side between the upper end portion (wall head portion 4a) and lower end portion (wall foot portion 4b) of the portion of the H-shaped steel that corresponds to the wall member.
A horizontal reinforcing bar 7a extending in the horizontal direction is provided on the upper surface of the channel steel 3. Furthermore, a vertical reinforcing bar 7b is provided on the H-shaped steel 6 along the axis and extending in the vertical direction.

At the upper end (wall head 4a) and lower end (wall foot 4b), the H-shaped steel 6, the channel steel 3, the horizontal reinforcing bars 7a, and the vertical reinforcing bars 7b are embedded inside with concrete.
The wall body 4c is formed integrally with the wall head 4a and the wall foot 4b as the wall member. In the wall body 4c, the channel steel 3, the horizontal reinforcing bars 7a, and the vertical reinforcing bars 7b are embedded in concrete between the upper and lower ends of the portion of the H-shaped steel 6 that corresponds to the wall member 4.

In this manner, the wall body 4c of the wall member 4 is a so-called reinforced concrete (RC structure) in which the channel steel 3, the horizontal reinforcing bars 7a, and the vertical reinforcing bars 7b are embedded inside the wall member 4 using concrete.
Meanwhile, the wall head 4a and wall foot 4b of the wall member 4 are SRC structures in which H-shaped steel 6, channel steel 3, and reinforcing bars 7a, 7b are embedded in concrete. In this way, the wall head and wall foot are SRC structures in which H-shaped steel, channel steel, and reinforcing bars are embedded in concrete, and function as a strong beam structure. This significantly improves the strength of the wall member, and makes it possible to suppress the occurrence of distortion, destruction, collapse, and subsidence of the wall member due to earth pressure.

In particular, as shown in Figures 3 and 4, in the wall head 4a and the wall foot 4b, the channel steel 3 is fixed to the outer and inner sides of the H-shaped steel 6, and in the wall main body 4c, the channel steel 3 is fixed to the outer side 6 of the H-shaped steel. Therefore, the thickness Wa of the wall head 4a and the wall foot 4b in the width direction (front-to-back direction of the wall) is greater than the thickness W of the wall main body 4c of the wall member 4.
That is, the wall head portion 4 a and the wall foot portion 4 b are shaped to protrude inward from the wall body portion 4 c of the wall member 4 .
As a result, the underside of the wall foot portion 4b of the wall member 4 has a surface shape (bottom surface shape) with a thickness Wa in the width direction (front-to-back direction of the wall) that is greater than the thickness of the wall main body portion 4c of the wall member 4, thereby making it possible to better prevent the occurrence of subsidence, heaping, and consolidation sliding.

The retaining wall 1 constructed in this manner is a composite structure in which the support piles 2 and wall members 4 are integrated, and the horizontal component of the earth pressure received by the wall members 4 is transmitted via the channel steel 3 to the H-shaped steel 6 at the top of the support pile 2 and to the bottom of the support pile 2.
In this case, since the wall head 4a and the wall foot 4b are of SRC structure as described above and function as a strong beam structure, the strength of the wall member is significantly improved compared to a wall member of RC structure in which the wall head 4a and the wall foot 4b are not formed, and distortion, destruction, collapse, and sinking of the wall member due to earth pressure can be prevented.

Furthermore, each component of the retaining wall 1 according to the embodiment of the present invention will be described in detail with reference to Figs.
(Support pile 2)
As shown in Fig. 1, the support pile 2 has, for example, a columnar portion 5 formed by cement milk in the ground, and an H-shaped steel 6 fixed to the columnar portion 5. The support pile 2 is fixed in the ground and its base is reinforced by the cement milk method, and is installed so that the axis of the support pile 2 is vertical.
The lower part of the H-shaped steel 6 is disposed inside the column part 5, and the upper part of the H-shaped steel 6 is exposed from the column part 5. The cement milk is produced, for example, by mixing a mixture of soil, water, cement, and bentonite in a mixing plant at a construction site.

The lower end of the support pile 2 is buried in the ground, and the lowermost end is fixed to the supporting layer of the ground. As shown in Fig. 1, a plurality of the support piles 2 are installed in parallel at a predetermined interval along the wall surface of the wall member 4 to be formed. The interval L1 between the support piles 2 is, for example, 2000 mm.
The portion of the H-shaped steel 6 on which the wall member 4 is to be provided is exposed without being covered by the columnar portion 5 formed by the cement milk. The wall member 4 is provided on the exposed portion of the H-shaped steel 6 via a channel steel 3, as shown in Figs. 3 and 4 .

The H-shaped steel 6 is a shaped steel manufactured by hot rolling, and as shown in FIG. 2, has a web 6a and two flanges 6b and 6c that are parallel to each other.
The plate surfaces of the flanges 6b, 6c of the H-shaped steel 6 are arranged parallel to the wall surface of the wall member 4, as shown in Figs.
Standard products based on JIS (Japanese Industrial Standards) or the like are used for the H-shaped steel 6. Note that a plurality of H-shaped steels 6 may be connected in the axial direction to one support pile 2. The H-shaped steels 6 can be joined together by, for example, high-strength bolts.

(Channel steel 3)
As shown in Figures 3 and 4, the channel steel 3 is, for example, an L-shaped equal-leg angle steel (it is not limited to equal-leg angle steel, but may be any angle steel) and has a web 3a and one flange 3b formed on one end side of the web 3a.
The channel steel 3 is a shaped steel manufactured by hot rolling, and is, for example, a standard product based on JIS. In the case of hot-rolled shaped steel, the channel steel 3 is stable in strength regardless of the product, unlike a cast one.

As shown in Figures 3 and 4, the flange 3b of this channel steel 3 is joined and fixed to the H-shaped steel 6, and the web 3a is disposed substantially horizontally in a cantilevered state.
That is, one surface of the channel steel 3 is joined and fixed to the H-shaped steel, and the channel steel 3 is attached to the H-shaped steel in an L-shape when viewed from the side. The channel steel 3 is fixed by welding or high-strength bolts.
As a result, the H-shaped steel 6 and the channel steel 3 are joined and fixed together through surface contact, and the transmission of force between the H-shaped steel 6 and the channel steel 3 is carried out by surface contact.
In the following description, the side of the H-shaped steel 6 on which the wall main body portion 4c of the wall member 4 is arranged (the flange 6b side) is referred to as the outer side, and the opposite side (the flange 6c side) is referred to as the inner side.

Regarding the fixing of the support pile 2 and the channel steel 3, the flange 3b of the channel steel 3 is fixed to the flanges 6b and 6c of the H-shaped steel 6 of the support pile 2 so that they are in surface contact with each other.
For example, the support pile 2 and the channel steel 3 are fixed to each other by joining them by arc welding. The members can be joined together by welding using a generator/welder that is commonly used at construction sites, and the joining work of the channel steel 3 to the support pile 2 can be performed on-site quickly and easily. Furthermore, the welding work on-site makes it easy to adjust the height position of the channel steel 3.

An impact test is carried out to check whether the channel steel 3 is properly fixed to the support pile 2. When viewed from the side, the channel steel 3 is attached to the H-beam in an L-shape, and the second flange (protrusion) of the channel steel as shown in Patent Document 1 is not formed, so it is possible to avoid the danger of the hammer hitting the tip of the second flange, causing it to flow sideways and hit the worker.

The support pile 2 and the channel steel 3 may be fixed to each other by joining with high-strength bolts (not shown). The high-strength bolts are, for example, torsion-type high-strength bolts (S10T M22), and the tightening torque can be confirmed by breaking a pintail formed in advance at the tip, ensuring uniform installation strength for multiple high-strength bolts.
The high-strength bolts are fastened using a shear wrench (for example, an ultra-short type). When using high-strength bolts, the work can be done by a generator alone.

In addition, on the outer surface (flange 6b side) of the H-shaped steel 6 between the upper end 6d and the lower end 6e of the part corresponding to the wall member 4 (the part corresponding to the wall main body portion 4c of the wall member 4), a plurality of channel steels 3 are provided at equal intervals along the axial direction of the H-shaped steel 6.
Then, in each channel steel 3, force is transmitted between the support pile 2 and the wall member 4. The distance L2 between the channel steels 3 is, for example, about 200 mm to 300 mm.

As shown in FIG. 3, a channel steel 3 is provided on each of the outer surface side (flange 6b side) and the inner surface side (flange 6c side) of the upper end portion 6d of the H-shaped steel 6 corresponding to the wall member 4.
Similarly, as shown in Figure 4, a channel steel 3 is provided on each of the outer surface side (flange 6b side) and the inner surface side (flange 6c side) of the lower end portion 6e of the H-shaped steel 6 corresponding to the wall member 4.
In addition, Figures 3 and 4 show a case in which two are provided on each of the outer side (flange 6b side) and inner side of the upper end 6d and lower end 6e of the part of the H-shaped steel 6 corresponding to the wall member 4, along the axial direction of the H-shaped steel 6.

The channel steel 3 is joined and fixed to the H-shaped steel 6 of each support pile 2, and is further embedded inside the wall member 4 with concrete, so that the support pile 2 and the wall member 4 are integrated together.
Furthermore, at the upper end 6d and lower end 6e of the portion of the H-shaped steel 6 corresponding to the wall member 4, the channel steel 3 is provided on the outer side (flange 6b side) and inner side (flange 6c side) of the H-shaped steel 6, respectively, to form the wall head portion 4a and wall foot portion 4b of the wall member 4.
When viewed in vertical cross section as shown in Figs. 3 and 4, the wall member 4 is formed in a so-called U-shape by a wall head portion 4a and a wall foot portion 4b protruding from a wall main body portion 4c.

When the height H (see FIG. 1) of the wall member 4 is, for example, 6000 mm, about 20 to 30 channel steels 3 are installed on the outer surface (flange 6 b side) of one H-shaped steel 6 .
It is preferable to vary the interval between the channel steels 3 depending on the earth pressure that the wall member 4 receives. For example, the interval L2 between the channel steels 3 in the lower part of the wall member 4 may be narrower than that in the upper part.

The channel steel 3 is joined and fixed to each of the support piles 2 (H-shaped steel 6) so that the horizontal height of all the support piles 2 (H-shaped steel 6) installed in parallel is the same.

(Reinforced concrete 7)
As shown in Figures 2 to 4, the reinforcing bars 7 include horizontal reinforcing bars 7a, which are, for example, main reinforcing bars, extending in the horizontal direction, and vertical reinforcing bars 7b, which are, for example, distribution reinforcing bars, extending in the vertical direction.
The horizontal reinforcing bars 7a have a diameter of, for example, D16 and are arranged horizontally on the channel steel 3. The horizontal reinforcing bars 7a are tied to the channel steel 3 and fixed thereto. On the other hand, the vertical reinforcing bars 7b have a diameter of, for example, D13. The vertical reinforcing bars 7b are tied to the horizontal reinforcing bars 7a and fixed thereto.

Since each horizontal reinforcing bar 7a is placed on a channel steel 3, the spacing between the vertical horizontal reinforcing bars 7a in the wall member 4 is equal to the spacing L2 between the channel steels 3, for example, about 200 mm to 300 mm.
The interval L3 between the horizontally extending vertical reinforcing bars 7b in the wall member 4 is, for example, about 200 mm to 300 mm. The horizontal reinforcing bars 7a and the vertical reinforcing bars 7b arrange the reinforcing bars 7 in a lattice pattern inside the wall member 4.

As shown in Figures 2 to 4, the horizontal reinforcing bars 7a (7) of the wall member 4 are placed horizontally on the horizontal webs 3a of multiple channel steels 3 of the same height, and the horizontal reinforcing bars 7a (7) are tied to the channel steels 3. This allows force to be transmitted between the channel steels 3 and the horizontal reinforcing bars 7a (7) of the wall member 4, and the stress applied to the wall member 4 is reliably transmitted to the support piles 2 via the channel steels 3.

On the horizontal web 3a of the channel steel 3, for example, two lateral reinforcing bars 7a (7) of the wall member 4 are placed.
Therefore, with the channel steel 3 fixed to the flanges 6b, 6c of the H-shaped steel 6 of the support pile 2, the reinforcing bar 7 placed on the web 3a of the channel steel 3 can be installed at a fixed position relative to the flange surface of the H-shaped steel 6.

When arranging the horizontal reinforcing bars 7a in the wall member 4, the reinforcing bars 7 can be arranged horizontally simply by placing the reinforcing bars 7a on multiple channel steels 3, making the arrangement easy. Furthermore, since it is easy to arrange the horizontal reinforcing bars 7a on the horizontal webs 3a of the channel steels 3 while maintaining a predetermined distance between each other, the spacing between the reinforcing bars 7 can be accurately maintained.

(First, second, and third stirrups 10, 11, and 12)
As shown in Figures 3 and 4, the wall head portion 4a and the wall foot portion 4b of the wall member 4 have first stirrups 10 arranged so as to surround the horizontal reinforcing bars 7a provided in the channel steel 3. As shown in Figure 2, a plurality of first stirrups 10 are provided in the wall head portion 4a and the wall foot portion 4b of the wall member 4 in the extension direction of the wall member 4.

Specifically, as shown in Fig. 3, the first stirrups 10 are provided so as to surround the entire horizontal reinforcing bars 7a across the inner and outer surfaces of the upper end of the portion of the H-shaped steel 6 that corresponds to the wall member 4. Therefore, the first stirrups 10 have a rectangular shape that is long in the width direction of the wall member as shown in Fig. 6.
Furthermore, as shown in Fig. 2, a plurality of first stirrups 10 are provided between a plurality of parallel H-shaped steels 6. When the interval between the first stirrups 10 between the plurality of H-shaped steels 6 is 100 mm or less, for example, D10 is used, and when the interval between the first stirrups 10 exceeds 100 mm, for example, D13 is used.

Similarly, as shown in FIG. 4, the first stirrups 10 are arranged to surround the entire horizontal reinforcing bar 7a across the inner and outer sides of the lower end of the portion of the H-shaped steel 6 that corresponds to the wall member 4, and further, as shown in FIG. 2, multiple first stirrups 10 are arranged between multiple H-shaped steels 6 arranged in parallel.

When the spacing between the first stirrups 10 between the multiple H-shaped steels 6 is 100 mm or less, for example, D10 is used, and when the spacing between the first stirrups 10 is more than 100 mm, for example, D13 is used.

The contact points between the first stirrups 10 and the horizontal and vertical reinforcing bars 7a and 7b are then connected by ties.
In this way, the first stirrup 10 is provided at each of the upper end 4a and the lower end 4b so as to surround the entire horizontal reinforcing bars 7a arranged on the outer and inner sides of the channel steel 3, thereby improving the strength of the upper end 4a and the lower end 4b of the wall member 6.

2 to 4, in addition to the first stirrups 10, second stirrups 11 are arranged so as to entirely surround the horizontal reinforcing bars 7a arranged in the channel steel 3 fixed to the outer surface side of the exposed H-shaped steel 6. A plurality of the second stirrups 11 are arranged at each of the upper end 6a and the lower end 6b, facing the H-shaped steel and spaced apart from each other at a predetermined interval.
Moreover, the third stirrups 12 are arranged so as to entirely surround the horizontal reinforcing bars 7a arranged in the channel steel 3 fixed to the inner surface side of the exposed H-shaped steel 6. A plurality of the third stirrups 12 are arranged at each of the upper end 6a and the lower end 6b, facing the H-shaped steel and spaced apart by a predetermined distance.
7(a) and 7(b), the second stirrup 11 and the third stirrup 12 have a rectangular shape shorter in the width direction of the wall member 4 than the first stirrup 10. As the second stirrup 11 and the third stirrup 12, for example, D10 and D13 are used.

When the second stirrup 11 and the third stirrup 12 are provided adjacent to the vertical reinforcing bar 7b, the second stirrup 11 and the third stirrup 12 are tied to the vertical reinforcing bar 7b and the horizontal reinforcing bar 7a.
If the second stirrup 11 and the third stirrup 12 are not provided adjacent to the vertical bars 7b, the second stirrup 11 and the third stirrup 12 are tied to the transverse reinforcing bars 7a.

In this way, at each of the upper end 4a and the lower end 4b, the second stirrup 11 is provided to surround the entire horizontal reinforcing bar 7a arranged on the outer side, and the third stirrup 12 is provided to surround the entire horizontal reinforcing bar 7a arranged on the inner side of the channel steel 3, thereby further improving the strength of the upper end 4a and the lower end 4b of the wall member 4.

(First width stopper 15, second width stopper 16)
As shown in FIG. 2 , a plurality of first width stop bars 15 and a plurality of second width stop bars 16 are provided between a plurality of H-shaped steels 6 provided in parallel.
The first width stop bars 15 and the second width stop bars 16 are arranged between the vertical reinforcing bars 7 b and are provided on the horizontal reinforcing bar side closer to the H-shaped steel 6 .

The first width-retaining bars 15 and the second width-retaining bars 16 are reinforcing bars having U-shaped ends, as shown in FIG.
In addition, the first width stop bars 15 and the second width stop bars 16 are tied to the upper and lower horizontal reinforcing bars 7a arranged on the channel steel 3 provided in the vertical direction on the outer and inner sides, which are reinforcing bars 7a arranged on the H-shaped steel 6 side, and the first stirrup bars 10.

Here, width retaining bars refer to reinforcing bars placed in the middle of the beam in the direction of the main bars in order to secure the shape of the stirrup bars.
In addition, a first width stop bar 15 and a second width stop bar 16 are provided not only at the upper end 6d of the H-shaped steel 6 shown in Fig. 5 but also at the lower end 6e (not shown). The width stop bars 15, 16 at the lower end 6e are disposed in the same manner as at the upper end 6d of the H-shaped steel 6.

In this way, by using the first width-retaining bars 15 and the second width-retaining bars 16, the strength of the wall member can be increased, and it can reliably support the horizontal component of earth pressure for a long period of time.

(Wall member 4)
As described above, the wall member 4 is in contact with the soil and receives the horizontal component of earth pressure. As described above, the wall member 4 is composed of a wall head portion 4a, a wall foot portion 4b, and a main body portion 4c between the wall head portion 4a and the wall foot portion 4. The wall member 4 is installed along a plurality of support piles 2 arranged in parallel, as shown in FIG.
The wall surface of the wall member 4 is formed perpendicular to the horizontal plane as shown in Figures 3 and 4. The thickness of the wall member 4 is determined according to the earth pressure that the wall member 4 is subjected to.

The thickness W of the wall member 4 is, for example, about 200 mm to 250 mm. The thickness W of the wall member 4 depends on the height of the surface of the wall member 4. For example, when the height of the surface of the wall member 4 is 3 m, the thickness W of the wall member 4 is set to 250 mm.
Furthermore, the thickness Wa of the wall head portion 4a and the thickness Wb of the wall foot portion 4b are, for example, about 600 mm to 650 mm, assuming that the thickness of the H-shaped steel 6 is 400 mm.

As mentioned above, the wall member 4 has a channel steel 3 embedded inside and is integrated with the support pile 2. When it receives the horizontal component of earth pressure, it transmits the force to the support pile 2 via the channel steel 3, which is a structural steel placed inside.

As described above, the wall body 4c (the portion between the wall head 4a and the wall foot 4b) is made of reinforced concrete (RC structure) with reinforcing bars 7 arranged inside the concrete.
Furthermore, the wall head 4a and wall foot 4b have a so-called SRC (Steel Reinforced Concrete) structure, since the H-shaped steel 6, the channel steel 3, the reinforcing bars 7, and the stirrups 10 are embedded in concrete.
Furthermore, since the wall head 4a and wall foot 4b of the wall member 4 can be made of a high-strength beam structure, the strength of the wall member is significantly improved, and distortion of the wall member due to earth pressure, destruction such as shear failure, and collapse of the wall member can be prevented.

Furthermore, the wall foot portion 4b of the wall member 4 is installed and embedded to a position (into the ground) below the ground surface below the step portion.
As described above, the wall foot 4b of the wall member 4 is a high-strength beam structure, and the underside of the wall foot 4b of the wall member 4 is formed into a surface shape whose length in the width direction (front-to-back direction of the wall) is greater (width Wb) than the thickness W of the wall main body portion 4c of the wall member 4.

Therefore, by installing the planar wall foot 4b with a large length (width Wb) in the width direction (front-to-back direction of the wall) in the ground, it is possible to prevent subsidence and heaving that may occur depending on the nature of the ground. Also, by adjusting the embedment depth, it is possible to prevent the phenomenon (arc slide) in which the soil above the step of the land (back soil) passes under the retaining wall 1 due to consolidation settlement and pushes up the excavation bottom ground below the step.
As shown in FIG. 4, the wall base 4b of the wall member 4 to be installed underground can be installed more stably by placing it on basin concrete 14 formed on top of the ground that has been solidified with crushed stone 13.

(Method of constructing retaining wall 1)
Next, a method for constructing the retaining wall according to this embodiment will be described. The method for constructing the retaining wall is basically the same as the method described in Patent Document 1, except for the portion for forming the wall head portion 4a and the wall base portion 4b.
First, at the site, the support piles 2 are erected. The support piles 2 are erected by a pre-boring and cement milk injection compaction method.

The pile core is determined by marking a piece of steel called a ruler, which serves as a marker for the installation position of the H-beam 6, and the auger (drill) of the construction machinery used for installation is set based on the markings. The auger then drills a hole to the specified depth, and is then withdrawn at the same speed as when the hole was drilled. The soil is removed while cement milk is injected. This prevents the pressure of the cement milk from collapsing the wall of the drilled hole.

Next, the H-shaped steel 6 is lifted by the construction machine, moved to the top of the borehole, and set up in the borehole.
If, after the support piles 2 have been erected, it is necessary to excavate in front of the support piles 2 on sloping ground or the like, cross sheet piles are buried in the ground between the support piles 2 and stacked vertically before excavation, and then the front side of the support piles 2 can be excavated in the same manner as in the construction method of a temporary retaining wall.

After the erection of the plurality of support piles 2 is completed, the channel steel 3 is fixed to the support piles 2. First, the fixing position of the channel steel 3 is determined on the flange of the support pile 2 by marking out.
The channel steel 3 is fixed by welding or high-strength bolts. After the fixing position of the channel steel 3 is determined on-site, the channel steel 3 is fixed by welding or high-strength bolts. Whether the channel steel 3 is properly fixed to the support pile 2 is inspected by impact testing.

After all the channel steels 3 are fixed to the support piles 2, the reinforcing bar arrangement work is carried out to form the wall members 4. The horizontal reinforcing bars 7a can be easily arranged by placing them on the channel steels 3, which are shaped steel. In addition, vertical reinforcing bars 7b are arranged between the channel steels 3 in parallel to the axis of the H-shaped steel 6.
The reinforcing bars 7 of the wall member 4 are then positioned by binding the horizontal reinforcing bars 7a to the channel steel 3 and binding the vertical reinforcing bars 7b to the horizontal reinforcing bars 7a.

Furthermore, first stirrups 10 are arranged so as to surround the horizontal reinforcing bars 7a across the inner and outer surfaces of the upper end 6d of the H-shaped steel 6 in the portion corresponding to the wall member 4. As shown in FIG. 2, a plurality of first stirrups 10 at the upper end 6d are arranged between the plurality of H-shaped steels 6 arranged in parallel.
In addition, the first stirrups 10 are arranged so as to surround the horizontal reinforcing bars 7a across the inner and outer surfaces of the lower end 6e of the H-shaped steel 6 in the portion corresponding to the wall member 4. A plurality of the first stirrups 10 at the lower end 6e are arranged between the plurality of H-shaped steels 6 arranged in parallel.
Furthermore, a first width stop bar 15 and a second width stop bar 16 are arranged between the vertical reinforcing bars 7 b and are disposed on the horizontal reinforcing bar side close to the H-shaped steel 6 .

Where vertical reinforcing bars 7b are present, the first stirrups 10, the horizontal reinforcing bars 7a and the vertical reinforcing bars 7b are tied together.
Furthermore, where no vertical reinforcing bars 7b are present (where the first width stop bars 15 and the second width stop bars 16 are present), the first width stop bars 15 and the second width stop bars 16 are upper and lower horizontal reinforcing bars 7a arranged on the channel steel bars 3 provided in the vertical direction on the outer and inner sides, and are tied to the reinforcing bars 7a arranged on the H-shaped steel bars 6 side.

Furthermore, as shown in Fig. 2, a plurality of second stirrups 11 and third stirrups 12 are provided opposite the H-shaped steel 6. The second stirrups 11 and the third stirrups 12 are tied to the vertical reinforcing bars 7b and the horizontal reinforcing bars 7a, and when the vertical reinforcing bars 7b are not present, they are tied to the horizontal reinforcing bars 7a.
In this way, by providing the second stirrups 11 and the third stirrups 12, the strength of the upper end portion 4a and the lower end portion 4b of the wall member 4 can be further improved.

Next, the concrete portion of the wall member 4 is formed.
The wall members 4 are formed by cast-in-place concrete. That is, a formwork is set up, concrete is poured, and the formwork is removed after a predetermined concrete strength is ensured. In this way, the structure of the retaining wall 1 in which the wall members 4 are integrated with the support piles 2 is completed.

As described above, according to this embodiment, the wall member 4 made of reinforced concrete receives the horizontal component of the earth pressure and transmits the force to the support pile 2 via the channel steel 3, which is a shaped steel placed inside. The retaining wall 1 has a composite structure in which the support pile 2, which is an H-shaped steel, and the wall member 4 (wall main body 4c), which is reinforced concrete (RC structure), are integrated.

In particular, the head 4a and base 4b of the wall member 4 are SRC structures in which H-shaped steel 6, channel steel 3, and reinforcing bars 7 are embedded in concrete, and function as a strong beam structure. This improves the strength of the wall member 4, making it possible to prevent distortion and damage to the wall member 4 and ensure long-term support against the horizontal component of earth pressure.
In addition, the underside of the wall foot portion 4b of the wall member 4 has a surface shape whose length (width Wb) in the width direction (front-to-back direction of the wall) is greater than the thickness W of the wall main body portion 4c of the wall member 4, thereby preventing the occurrence of subsidence, heaving, and consolidation sliding that may occur depending on the properties of the ground.

Furthermore, when performing impact testing, as shown in Patent Document 1, the second flange of the channel steel does not protrude, so impact testing can be performed properly and the risk of the hammer hitting the tip of the second flange, drifting sideways, and hitting the worker can be avoided.

In the above embodiment, the channel steel 3 is L-shaped (angle steel) having a web 3a and one flange 3b formed on one end side of the web 3a, but in the present invention, the shape of the channel steel 3 is not limited to this form.
For example, the web portion of a channel steel having a U-shaped cross section with flanges on both the left and right sides of the web may be joined in surface contact with the flanges of the H-shaped steel 6, and reinforcing bars may be placed in the flange portions.

Second Embodiment
Next, a second embodiment of the present invention will be described. Fig. 9 is a plan view showing a part of a retaining wall 1 in the second embodiment.
In the above-described first embodiment, an example of a configuration in which the wall main body 4c of the wall member 4 is a single flat plate was described. However, in the second embodiment, a configuration in which two vertically arranged wall members 4A, 4B are connected at a predetermined intersecting angle is described.
In this embodiment, two wall members are taken as an example for explanation, but the number of wall members is not limited to two, and a plurality of wall members can be connected.

9 shows an example in which wall members 4A and 4B are connected at an angle of 90°. Since the configurations of wall members 4A and 4B are similar to the configuration of the wall member 4 described in the first embodiment, the same reference numerals are used and detailed description thereof will be omitted.
In this embodiment, the wall member 4A and the wall member 4B are connected at an angle of 90°. However, this is not limited to 90°, and the angle may be less than 90° or more than 90°.

As shown in FIG. 9, the connection portion R between the wall members 4A and 4B is composed of horizontal reinforcing bars 7a, vertical reinforcing bars 7b, the first stirrups 10, and concrete, so that the wall members 4A and 4B can be connected at a desired cross angle.
The second stirrups 11 and the third stirrups 12 can be arranged as appropriate, as shown in Fig. 9. Moreover, the upper end of the wall member 4A and the upper end of the wall member 4B are part of a beam structure (SRC structure), and the lower end of the wall member 4A and the lower end of the wall member 4B are part of a beam structure (SRC structure), and these are formed as an integrated wall member by connecting the beams. Therefore, a greater strength can be obtained compared to when the wall members are formed as separate wall members.

Third Embodiment
A third embodiment of the present invention will now be described. Fig. 10 is a front view of a retaining wall according to the third embodiment of the present invention, and Figs. 11 and 12 are cross-sectional views of the retaining wall of Fig. 10, with Fig. 11 being a cross-sectional view of the wall head portion 4a and Fig. 12 being a cross-sectional view of the wall foot portion 4b. In Figs. 10 to 13, the same reference numerals are used for the same components as those described in the first embodiment, and detailed descriptions thereof will be omitted.

As shown in Figures 10, 12, and 13, the retaining wall 1 has a wall head 4a and a wall foot 4b, as in the first embodiment, and this third embodiment is characterized in that a connecting member 17 is provided at the upper end of the wall head 4a to connect the H-shaped steel 6 that constitutes the support piles. Note that the connecting member 17 may also be provided at the wall foot 4b, as shown in Figures 10 and 12.

The connecting member 17 is provided to prevent the H-shaped steel 6 from tilting. That is, the H-shaped steel 6 is lifted by a construction machine, moved to the top of a borehole, and set in the borehole. The H-shaped steel 6 is then fixed in the borehole with cement milk.
At this time, if even one of the multiple H-shaped steels 6 tilts, it becomes difficult to form the wall head 4a, wall foot 4b, and wall body 4c. To prevent this from happening, a connecting member 17 is provided.

As described above, the connecting member 17 is disposed at the head of the wall, extends laterally of the wall main body portion 4 c , and is fixed to the upper ends of the plurality of H-shaped steel beams 6 .
The connecting member 17 is not particularly limited as long as it can prevent the H-shaped steel 6 from tilting, but for example, an isosceles angle steel (or angle steel), a channel steel, or a steel material conforming to the JIS standard can be used. The fixing is performed by welding the connecting member 17 to the H-shaped steel 6 or by using bolts.
In this way, by connecting the H-shaped steel 6 to each other using the connecting members 17, the inclination of the H-shaped steel 6 is suppressed, and the wall head portion 4a, wall foot portion 4b, and wall main body portion 4c can be formed with high precision.

REFERENCE SIGNS LIST 1 Retaining wall 2 Support pile 3 Channel steel 3a Web 3b Flange 4 Wall member 4a Wall head 4b Wall foot 4c Wall body 5 Column 6 H-shaped steel 7 Reinforcing bar 7a Horizontal reinforcing bar 7b Vertical reinforcing bar 10 First stirrup 11 Second stirrup 12 Third stirrup 15 First width stop bar 16 Second width stop bar

Claims (11)

A retaining wall that receives a horizontal component of earth pressure by a wall member,
A plurality of support piles each having a columnar portion formed of cement milk in the ground and an H-shaped steel having a lower portion disposed inside the columnar portion and an upper portion exposed from the columnar portion;
A plurality of channel steels fixed to the outer and inner sides of the upper and lower ends of the H-shaped steel portions corresponding to the wall members, and fixed to the outer side between the upper and lower ends of the H-shaped steel portions corresponding to the wall members;
A horizontal reinforcing bar disposed on the upper surface of the channel steel and extending laterally;
A vertical reinforcing bar arranged along the axis of the H-shaped steel and extending vertically;
a wall head and a wall foot formed at the upper and lower ends of the portion of the H-shaped steel corresponding to the wall member, in which the H-shaped steel, the channel steel, the horizontal reinforcing bars, and the vertical reinforcing bars are embedded inside with concrete;
a wall body portion formed integrally with the wall head portion and the wall foot portion as the wall member, the channel steel, the horizontal reinforcing bars, and the vertical reinforcing bars being embedded in concrete between the upper end portion and the lower end portion of the portion corresponding to the wall member of the H-shaped steel;
A retaining wall comprising: The wall head and wall foot are shaped to protrude inward from the wall body,
2. The retaining wall according to claim 1, wherein the wall head portion is formed to be wider than the wall body portion, and the wall foot portion is formed to be wider than the wall body portion. At the wall head and wall foot,
Further, the wall member of the H-shaped steel is provided with first stirrups arranged at the upper end and the lower end so as to surround the horizontal reinforcing bars arranged in a channel steel fixed to the outer surface side and the inner surface side of the upper end and the lower end of the part corresponding to the wall member of the H-shaped steel,
The retaining wall according to claim 1, characterized in that the H-shaped steel, the channel steel, the horizontal reinforcing bars, the vertical reinforcing bars and the first stirrup formed at the upper and lower ends of the portion of the H-shaped steel corresponding to the wall member are embedded inside with concrete. The channel steel is an angle steel,
A retaining wall as described in claim 1, characterized in that one side of the angle iron is joined to an H-shaped steel, and when viewed from the side, the angle iron is attached to the H-shaped steel in an L-shape. At least two of the channel steels are provided in the vertical direction on the outer surface side and the inner surface side of the upper end portion and the lower end portion of the portion of the H-shaped steel corresponding to the wall member,
A retaining wall as described in claim 3, characterized in that it is provided with first stirrups arranged at each of the upper and lower ends of the part of the H-shaped steel corresponding to the wall member, so as to surround horizontal reinforcing bars arranged on at least two channel steels fixed to the outer and inner sides of the upper and lower ends of the part. The retaining wall according to claim 3, characterized in that the first stirrups are provided in a plurality at predetermined intervals between the H-shaped steels. If the first stirrup is provided adjacent to a vertical reinforcing bar, the first stirrup is tied to the vertical reinforcing bar and to the horizontal reinforcing bar,
7. A retaining wall according to claim 6, characterized in that, if the first stirrup is not placed close to a vertical reinforcing bar, it is tied to a horizontal reinforcing bar and to a width stop bar which is tied to the horizontal reinforcing bars arranged above and below. A second stirrup is disposed at each of the upper end and the lower end so as to face the outer surface side of the H-shaped steel and surround the entire horizontal reinforcing bar disposed in the channel steel fixed to the outer surface side of the H-shaped steel; and
A third stirrup is disposed at each of the upper end and the lower end so as to surround the entire horizontal reinforcing bar disposed in the channel steel fixed to the inner side of the H-shaped steel, facing the inner side of the H-shaped steel; and
The retaining wall according to claim 3, further comprising: The second stirrups and the third stirrups are provided in plurality at predetermined intervals facing the H-shaped steel,
When the second stirrup and the third stirrup are provided adjacent to the vertical reinforcing bars, the second stirrup and the third stirrup are tied to the vertical reinforcing bars and the horizontal reinforcing bars,
9. A retaining wall according to claim 8, characterized in that, if the second and third stirrups are not provided in contact with the vertical reinforcing bars, the second and third stirrups are tied to the horizontal reinforcing bars. A plurality of the wall members each having a linear shape in a plan view are provided,
2. The retaining wall according to claim 1, wherein the plurality of wall members are connected at a predetermined cross angle to form an integrated wall member. The retaining wall described in claim 1, characterized in that the wall head is provided with connecting members that connect the H-shaped steel that constitutes the support piles to each other.

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