JPH09228395A - Retaining wall structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the term of works and reduce the construction cost by providing a no-earth space on the retaining wall back surface side in a reinforced concrete retaining wall. SOLUTION: The wall system of a retaining wall is formed of a front wall 3a and a back wall 3b lower than it. A floor system 4 is laid between the front wall system 3a and the back wall system 3b, and a space enclosed by the bottom system 1, the front wall system 3a, the back wall system 3b, and the floor system 4 is ensured. Further, this part forms a no-earth space 6 to back filling earth 5. This no-earth and sand space 6 is provided, whereby the contact pressure to the retaining wall foundation is minimized, and the tipping moment in a point A is also minimized.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a retaining wall structure.

[0002]

2. Description of the Related Art Conventionally, as a structural method for providing a step H on the ground as shown in FIG. 23, generally, an L-shaped retaining wall made of a reinforced concrete structure composed of a bottom slab 1 and a wall slab 2 is used. There are many.

Regarding the stability of the rear surface (diagonal portion) defined by the bottom slab 1 and the wall slab 2 of this L-shaped retaining wall, (i) ground pressure, (ii) slip due to earth pressure, (iii) lower front edge It has been confirmed that it is safe by studying points such as falls at point A.

[0004]

However, when the step H becomes large, (i) the ground pressure becomes large and a pile is required except for a solid ground.
In terms of construction cost, it is more expensive than the direct foundation, especially when the pile length is long.

The object of the present invention is to eliminate the disadvantages of the prior art, to reduce the ground contact pressure acting on the retaining wall foundation, and to reduce the overturning moment at the lower end of the front surface, so that the direct foundation without piles is stable. It is to provide a retaining wall structure that can be.

[0006]

In order to achieve the above object, the present invention provides a non-sand space on the back side of a retaining wall in a reinforced concrete retaining wall consisting of a bottom slab and a wall slab, and , A bottom slab, a front wall slab, a back wall slab, and a floor slab, or formed by arranging a foamed synthetic resin. The gist is to make it a slope that can fall.

According to the present invention, the ground pressure acting on the retaining wall foundation is reduced by providing the non-sand space on the rear side of the retaining wall, and the overturning moment at the lower end of the front surface is also reduced.

According to the second aspect of the present invention, in addition to the above-mentioned action, as one embodiment for easily creating a non-sand-sand space, a bottom plate, a front wall plate, a back wall plate, and a floor plate are surrounded and bent. In this case, the space portion can be secured by the structure of the retaining wall itself before backfilling, and the backfilling earth and sand can be prevented from entering the space portion to form a non-sandy space.

According to the third aspect of the present invention, as one mode for easily creating the non-sand space, by arranging a foamed synthetic resin such as styrofoam (or Styrofoam) before backfilling, The non-earth and sand space can be occupied by the foamed synthetic resin.

According to the fourth aspect of the present invention, by making the back side of the non-earth and sand space an inclined surface, the earth pressure can be further reduced and a more stable retaining wall can be obtained.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an explanatory view showing a first embodiment of a retaining wall structure of the present invention, which is an L-shaped retaining wall made of reinforced concrete made up of a bottom slab 1 and a wall slab as in the conventional example shown in FIG.

According to the present invention, the retaining wall has two wall slabs, a front wall 3a and a rear wall 3b lower than the front wall 3a, and a floor slab 4 is bridged between the front wall slab 3a and the rear wall slab 3b. Then, a space surrounded by the bottom slab 1, the front wall slab 3a, the back wall slab 3b, and the floor slab 4 was secured, and this portion was used as a non-sand space 6 for the backfill soil 5.

By providing the non-earth-sand space 6 in this way, the ground contact pressure against the retaining wall foundation is reduced, and the overturning moment at point A is also reduced. (Refer to the arrow indicating the ground pressure in Figs. 1 and 23)

Further, in this embodiment, the protrusion 1a is formed at the tip of the bottom plate 1 from the lower end of the front wall plate 3a to the front. By doing so, it is more advantageous against the ground contact pressure and the fall pressure.

FIG. 2 shows a second embodiment of the present invention. A space surrounded by the bottom slab 1, the front wall slab 3a, the back wall slab 3b and the floor slab 4 of the first embodiment is secured, In addition to the structure where this part is the non-sand space 6 for the backfill soil 5,
The back wall slab 3b was tilted so as to fall toward the back. This inclination θ is about −10 ° to −20 °.

As a result, the rear surface side of the non-earth and sand space 6 becomes an inclined surface, the earth pressure can be further reduced, and a more stable retaining wall becomes possible. Also in the case of the second embodiment, although not shown, the protrusion 1a at the tip of the bottom plate 1 may be formed.

As a construction procedure, FIGS. 3 to 6 show the case where the construction is performed by using cast-in-place concrete. As shown in FIG.
The connecting rebar 18 is projected from the above.

As shown in FIG. 4, the formwork of the front wall slab 3a and the back wall slab 3b, reinforcement work and concrete placement are carried out, and FIG.
As shown in FIG. 3, the front wall slab 3a is attached with the post 8 anchor 7 by the angle member or the channel member, and the back wall slab 3b is also attached by the post 8 with the steel plate frame 9. Set up.

The deck plate 10 is supported between the front wall slab 3a and the back wall slab 3b by being supported by the coupling hardware 8, and the connecting reinforcing bar 18 is projected from the front wall slab 3a. Arrange the bars, cast concrete, and construct the floor slab 4 (see FIG. 6). After that, if you apply backfill soil 5,
The non-sandy space 6 can be secured.

FIGS. 7 to 11 show a case where a precast concrete (PC) plate is used, in which a bottom plate 1 made of precast with an embedded nut 11 is set, and a steel rod 12 whose end is screwed into the embedded nut 11 is installed. Is inserted into the through hole 13 to raise the front wall plate 3a and the back wall plate 3b made of precast from the bottom plate 1.

A precast floor slab 4 is bridged over the front wall slab 3a and the back wall slab 3b, and similarly, a steel rod 12 is inserted through a through hole 13
And fix it.

If necessary, the front wall slab 3a and the back wall slab 3
b, the brace 14 is installed in the space surrounded by the floor slab 4,
If the backfill soil 5 is applied as shown in 11, the non-sand space 6 can be secured.

As described above, the bottom plate 1, the front wall plate 3a, the back wall plate 3b, and the floor plate 4 are connected by the steel rods 12.
13 is a front wall slab 3a and a back wall slab 3 due to the sleeve.
b, it is formed on the floor slab 4, and the joint is filled with tro, and the end of the steel rod 12 is fastened with a nut, and then this portion is filled with mortar.

Further, the bottom slabs 1 arranged in a row are also filled with through holes 13 at the joints of the wall slabs as shown in FIG. The fastening metal pieces 15 are embedded in each bottom slab 1, and the fastening metal pieces 15 are connected to each other by the attachment plate 16 and the joint portion is mortar-filled.

16 and 17 are a third embodiment and a fourth embodiment of the present invention.
In the embodiment, the L-shaped retaining wall made of reinforced concrete is composed only of the bottom slab 1 and the wall slab 2 as the front wall as in the conventional example shown in FIG. 23. A block of foamed synthetic resin 17 such as Styrofoam (or Styrofoam) is placed behind this foamed synthetic resin.
In 17, the non-sand space 6 in the backfill soil 5 was secured.

Reference numeral 19 in the figure denotes a water drain pipe provided on the foamed synthetic resin 17. In the fourth embodiment of FIG. 17, the back surface side of the foamed synthetic resin 17 is an inclined surface that tilts toward the back surface.

18 to 23 show the construction procedure, as shown in FIG. 18, the bottom slab 1 is constructed by arranging and placing concrete. The connecting rebar 18 is projected from the bottom plate 1.

As shown in FIG. 19, the foam synthetic resin 17 is installed so as to also serve as the wall formwork on the back side.
A water draining pipe 19 made of a vinyl chloride pipe is installed in the. In this way, the foam synthetic resin 17 is also used as a wall mold to rationalize the form, and the drain synthetic pipe 17 is passed through to the wall slab 2 where the drain pipe 19 is to be constructed, and the foam synthetic resin 17 at the time of backfilling It can prevent rashes.

After arranging the wall slab 2, the front side mold 20 is set by using a separator 21 which penetrates into the water draining pipe 19, and the mold 20 ′ is also set on the foam synthetic resin 17. hand,
As shown in FIG. 21, wall concrete is poured to form the wall slab 2. In this way, the drainage pipe 19 is used for the arrangement of the separator 21, whereby rationalization can be achieved.

A permeable layer of gravel behind the foamed synthetic resin 17
22 is formed and backfilling soil 5 is applied to complete.

[0031]

As described above, the retaining wall structure of the present invention is
Since the ground pressure acting on the retaining wall foundation is reduced and the tipping moment at the lower end of the front surface is also reduced, a direct foundation without piles can be made stable, and even if there are large steps, no piles are required, so And the construction cost can be reduced.

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of a retaining wall structure of the present invention.

FIG. 2 is a side view showing a second embodiment of the retaining wall structure of the present invention.

FIG. 3 is a side view showing a first step of the first construction procedure.

FIG. 4 is a side view showing a second step of the first construction procedure.

FIG. 5 is a side view showing a third step of the first construction procedure.

FIG. 6 is a side view showing a fourth step of the first construction procedure.

FIG. 7 is a side view showing a first step of a second construction procedure.

FIG. 8 is a side view showing a second step of the second construction procedure.

FIG. 9 is a side view showing a third step of the second construction procedure.

FIG. 10 is a side view showing a fourth step of the second construction procedure.

FIG. 11 is a side view showing a fifth step of the second construction procedure.

FIG. 12 is a view on arrow A in FIG.

13 is a view on arrow B of FIG.

14 is a view on arrow C of FIG.

FIG. 15 is a view on arrow D in FIG.

FIG. 16 is a side view showing a third embodiment of the retaining wall structure of the present invention.

FIG. 17 is a side view showing a fourth embodiment of the retaining wall structure of the present invention.

FIG. 18 is a side view showing a first step of a third construction procedure.

FIG. 19 is a side view showing a second step of the third construction procedure.

FIG. 20 is a side view showing a third step of the third construction procedure.

FIG. 21 is a side view showing a fourth step of the third construction procedure.

FIG. 22 is a side view showing a fifth step of the third construction procedure.

FIG. 23 is a side view showing a conventional example.

[Explanation of Codes] 1 ... Bottom slab 1a ... Projection 2 ... Wall slab 3a ... Front wall slab 3b ... Rear wall slab 4 ... Floor slab 5 ... Backfill soil 6 ... Non-sand space 7 ... Post-installed anchor 8 ... Bonded hardware 9 … Iron plate formwork 10… Deck plate 11… Embedded nut 12… Steel bar 13… Through hole 14… Brace 15… Fastening hardware 16… Saddle plate 17… Foam synthetic resin 18… Connecting rebar 19… Drainage pipe 20, 20 ′… Formwork 21 ... Separator 22 ... Water permeable layer

Claims (4)

[Claims] 1. A retaining wall structure comprising a reinforced concrete retaining wall composed of a bottom slab and a wall slab, wherein a non-sand space is provided on the rear side of the retaining wall. 2. The retaining wall structure according to claim 1, wherein the non-sand-sand space is formed by surrounding and bending with a bottom slab, a front wall slab, a back wall slab, and a floor slab. 3. The retaining wall structure according to claim 1, wherein the non-earth and sand space is formed by disposing a foamed synthetic resin. 4. The retaining wall structure according to any one of claims 1 to 3, wherein the non-earth and sand space has an inclined surface such that the rear surface side is inclined toward the rear surface.