JP7115817B2 - Reinforced soil wall using large sandbags and retaining method using large sandbags - Google Patents

Description

The present invention relates to a reinforced earth wall using large sandbags and an earth retaining method using large sandbags.

As an example of a permanent structure that uses large sandbags that were temporarily erected for disaster recovery, the sides of a temporary earthen structure made up of stacked large sandbags are covered with gravel, etc. to form a buffer layer, which further provides a buffer. There is a permanent soil structure in which the surface of a layer is covered with a retaining wall (for example, Patent Document 1).

Japanese Patent No. 5913701

If a grain layer made of gravel, etc. is provided between a large sandbag and a retaining wall, the gravel will collapse downward when the retaining wall tilts forward due to the difference between the natural period of the retaining wall and the period of the seismic motion. As a result, the upper part of the granular material layer becomes a cavity. As a result, the upper portion of the retaining wall may bend toward the cavity and the permanent soil structure may collapse. An object of the present invention is to improve the earthquake resistance of permanent structures constructed using large-sized sandbags.

The reinforced earth wall for solving the above problems includes a plurality of large sandbags, an embankment formed between the natural ground and the large sandbags, a bearing plate supporting the large sandbags, and a base whose tip side is inserted into the embankment. A shaft member whose end side is fixed to the bearing plate, and a backing member filling a gap between the bearing plate and the large sandbag are provided.

ADVANTAGE OF THE INVENTION According to this invention, the seismic resistance of the permanent structure built using a large-sized sandbag can be improved.

The whole block diagram which shows 1st Embodiment of the reinforcement earth wall using a large-sized sandbag. Sectional drawing of the fixed part of a bearing pressure plate and a shaft member. The whole block diagram which shows 2nd Embodiment of the reinforcement earth wall using a large-sized sandbag. The whole block diagram which shows the 1st modification of the reinforcement earth wall using a large-sized sandbag. The whole block diagram which shows the 2nd modification of the reinforcement earth wall using a large-sized sandbag.

(First embodiment)
First, an embodiment of a reinforced earth wall using large sandbags will be described.
As shown in FIG. 1, the reinforcing soil wall 11 includes a plurality of large sandbags 21, an embankment 23 formed between the ground 22 and the large sandbags 21, a bearing plate 12 supporting the large sandbags 21, and a bearing plate. 12, and a backing material 14 for filling the gap between the bearing plate 12 and the large-sized sandbag 21. - 特許庁The shaft member 13 is inserted into the embankment 23 at its tip end and fixed to the bearing plate 12 at its base end. The shaft member 13 may be inserted up to the natural ground 22 through the embankment 23 . It is preferable that the natural ground 22 is step-cut.

The large sandbag 21 and embankment 23 constitute a temporary structure 20 . A "large sandbag" refers to a sandbag having a capacity of about 1 m ³ filled with a filling material, whereas a standard sandbag has dimensions of about 13 cm in height×35 cm in width×45 cm in length. The temporary structure 20 is suitable for emergency temporary construction in the event of a disaster, for example. The temporary structure 20 may also be constructed as part of a preplanned permanent structure construction process.

The large-sized sandbag 21 is configured by, for example, filling a bag-shaped or cylindrical sandbag with a filling material such as earth and sand. The temporary structure 20 is stabilized when the large sandbags 21 are stacked in a stepped manner so as to form a plurality of steps in the vertical direction. Under the large sandbags 21 at the bottom, it is preferable to bury a hardening part 25 made of crushed stone or improved soil.

When stacking the large-sized sandbags 21 in a stepped manner, it is preferable to lay the embankment reinforcing material 24 extending from the large-sized sandbags 21 into the embankment 23 for each step formed by arranging the plurality of large-sized sandbags 21 in the horizontal direction. The number of large sandbags 21 arranged in the depth direction (horizontal direction in FIG. 1) can be arbitrarily changed for each stage. When the embankment reinforcement 24 is laid, the seismic resistance of the temporary structure 20 increases due to the bearing pressure resistance and frictional resistance generated between the embankment reinforcement 24 and the embankment 23 . The embankment reinforcing material 24 can be laid not only at each stage but also at any position that requires reinforcement.

The embankment reinforcing material 24 is made of, for example, steel material, fiber, or plastic, and is formed in a planar shape, a net shape, or a belt shape. The embankment reinforcement 24 is preferably laid substantially horizontally. The embankment reinforcing material 24 may be laid under the large-sized sandbag 21 or may be sandwiched between the side surfaces of two large-sized sandbags 21 arranged side by side. Alternatively, a communication hole may be provided in the center of the large sandbag 21, and the rod-like embankment reinforcing material 24 may be passed through the communication hole. The embankment reinforcing material 24 can also be used in combination with different shapes.

When the embankment reinforcing material 24 is rod-shaped, a plate-like member (not shown) extending in the extending direction or a plate-like member (not shown) extending in a direction intersecting the extending direction is attached. good too. According to this configuration, the bearing pressure resistance and frictional resistance of the embankment reinforcing member 24 can be increased.

The bearing plate 12 is made of, for example, steel, fiber-reinforced plastic, or ultra-high-strength fiber-reinforced concrete. The bearing plate 12 does not necessarily have to cover the entire surface of the large sandbag 21 . However, when the coverage ratio of the large-sized sandbag 21 with the bearing plate 12 increases, the effect of suppressing the deformation of the temporary structure 20 increases.

The shaft member 13 is made of, for example, steel or fiber-reinforced plastic. When the pressure plate 12 is rectangular in front view, a plurality of shaft members 13 may be arranged in the longitudinal direction of one pressure plate 12 . The shaft members 13 may be inserted into the constructed temporary structure 20 at a predetermined density, and not all of them need to pass through the large sandbag 21 . Therefore, some shaft members 13 may be inserted between two adjacent large sandbags 21 . As an example, on the surface of the temporary structure 20, it is preferable to install about one shaft member 13 per 2 m ² .

When inserting the shaft member 13 into the temporary structure 20 , it is preferable to drill a bottomed insertion hole 15 and insert the shaft member 13 and the filler 16 into the insertion hole 15 . The filler 16 is, for example, cement milk or mortar. In this case, a spacer (not shown) that supports the shaft member 13 may be inserted into the insertion hole 15 so that the shaft member 13 is arranged near the center of the insertion hole 15 .

The shaft member 13 is preferably arranged so that the tip thereof faces downward with respect to the horizontal plane. In this case, if the length of the shaft member 13 from the front surface of the large sandbag 21 is L1, the length of the embankment reinforcing member 24 from the front surface of the large sandbag 21 is L2, and the inclination angle of the shaft member 13 with respect to the horizontal is α, L1 It is preferable that xcosα≧L2. By laying the embankment stiffeners 24 substantially horizontally and inserting the shafts 13 into the embankment 23 as deeply as or deeper than the embankment stiffeners 24, the stability of the permanent structure can be enhanced.

The backing material 14, such as cement bentonite, is a fluid when placed between the bearing plate 12 and the large sandbag 21, and solidifies in a state in which the gap between the bearing plate 12 and the large sandbag 21 is filled. is preferred. The flow of the backing material 14 at the time of arrangement makes it possible to fill the space between the bearing plate 12 and the large-sized sandbag 21 without gaps. When the backing material 14 is solidified, the bearing plate 12 is fixed to the large sandbag 21, and displacement is suppressed. The installation time can be shortened by changing the backing material 14 to, for example, an elastically deformable rubber plate.

As shown in FIG. 2, the bearing plate 12 is provided with a through hole 12a through which the shaft member 13 can be inserted, and a concave portion 12b in which the through hole 12a opens. should be placed. Then, the shaft member 13 does not protrude from the surface of the bearing pressure plate 12 . If the bearing pressure plate 12 is not provided with the concave portion 12b, the shaft member 13 and the fixing member 17 may protrude from the surface of the bearing pressure plate 12 .

When a threaded portion 13a is provided at the proximal end of the shaft member 13, a nut as a fixing member 17 can be screwed onto the threaded portion 13a. The shaft member 13 is fixed to the bearing plate 12 by fitting a washer 18 between the recess 12b and the opening of the through hole 12a and tightening the nut as the fixing member 17 . The method of fixing the shaft member 13 and the bearing pressure plate 12 is not limited to screwing, and they may be fixed by other methods such as fitting or welding. When the shaft member 13 inserted into the temporary structure 20 is fixed to the bearing plate 12 , the bearing plate 12 is integrated with the temporary structure 20 . As a result, the bearing plate 12 is in a state of supporting the large sandbag 21 .

If a cover (not shown) is fitted in the concave portion 12b so as to hide the fixing member 17, or the concave portion 12b is filled with mortar or the like so as to hide the fixing member 17, the fixing portion between the shaft member 13 and the bearing plate 12 can be protected. As well as being able to do it, it is also beautiful.

Next, an embodiment of an earth retaining method using the large sandbag 21 will be described.
First, as a sandbag installation step, a plurality of large sandbags 21 are placed in front of the ground 22 . Next, as an embankment step, an embankment 23 is formed between the large sandbag 21 and the ground 22 . The sandbag installation process and the embankment process are preferably performed alternately for each stage in which a plurality of large sandbags 21 are arranged side by side. In addition, as a reinforcing step, it is preferable to lay embankment reinforcing material 24 for each stage. For example, after performing the sandbag installation process, the embankment process, and the reinforcement process for the first stage, the second stage sandbag installation process, the embankment process, and the reinforcement process are performed on the first stage, and thereafter, sandbags are installed for each stage. A process, an embankment process, and a reinforcement process are repeated. Through these steps, the stepped temporary structure 20 is constructed.

When the temporary structure 20 is temporarily erected as a disaster countermeasure or the like, the subsequent steps are performed as permanent structure construction work after a predetermined period of time has elapsed. Assuming that the sandbag installation process, the embankment process and the reinforcement process related to the construction of the temporary structure 20 are the primary processes, and the process related to the construction of the permanent structure is the secondary process, the secondary processes include the placement process and the backfilling process. , an insertion step and a fixation step. When constructing the stepped temporary structure 20 from the lower stage as part of the construction process of the permanent structure planned in advance, the secondary process of the lower stage and the primary process of the upper stage are carried out in parallel. may

In the placement step, the bearing plate 12 is placed in front of the large sandbag 21 . When the large-sized sandbags 21 are stacked in steps, it is preferable to arrange a plurality of bearing plates 12 horizontally for each step.
In the back-filling step, the gap between the bearing pressure plate 12 and the large-sized sandbag 21 is filled with the back-filling material 14.例文帳に追加When the backing material 14 is fluid when placed, the gap between the bearing plate 12 and the large sandbag 21 is surrounded by a formwork, and the backing material 14 is poured into the formwork to remove the backing material 14. The formwork should be removed after hardening.

In the inserting step, the tip side of the shaft member 13 is inserted into the embankment 23 . When drilling the insertion hole 15 , it is preferable to drill through the through hole 12 a of the bearing plate 12 and then put the shaft member 13 and the filler 16 into the insertion hole 15 . If the through hole 12a is excavated after the bearing pressure plate 12 is arranged, the position of the through hole 12a and the shaft member 13 is less likely to shift.

The back-filling step may be performed after the placement step and before drilling the insertion hole 15 , or may be performed after the shaft material 13 and the filler 16 are put into the drilled insertion hole 15 . When the backing material 14 is arranged before excavating the insertion hole 15 , the insertion hole 15 is preferably excavated so as to penetrate the backing material 14 and the large-sized sandbag 21 .

In the fixing step, the base end side of the shaft member 13 is fixed to the bearing plate 12 . For example, when a threaded portion 13a is provided at the proximal end of the shaft member 13, a washer 18 is fitted between the through hole 12a and the opening of the through hole 12a, and a nut (fixing member 17) screwed to the threaded portion 13a is tightened. . The fixing step is preferably performed after the backing material 14 is solidified in the backing step.

Next, the operation of the reinforcing earth wall 11 and earth retaining method of this embodiment will be described.
Since the shaft member 13 is inserted through the large sandbag 21 to the embankment 23 , when the bearing plate 12 is about to be displaced due to an earthquake motion or the like, the bearing pressure resistance between the large sandbag 21 and the embankment 23 is formed between the shaft member 13 and the embankment 23 . Force and frictional resistance act. This suppresses the displacement of the bearing plate 12, thereby avoiding the permanent structure from collapsing.

In this way, the external force acting on the bearing pressure plate 12 due to seismic motion or the like is dispersed and transmitted to the large sandbag 21 and the embankment 23 through the shaft member 13 . Therefore, the reinforced earth wall 11 has high earthquake resistance of the permanent structure compared to the case where the earth pressure is directly supported by the retaining wall installed in front of the temporary structure 20 .

According to the reinforcing earth wall 11 and earth retaining method of this embodiment, the following effects can be obtained.
(1-1) Since the bearing plate 12 is integrated with the temporary structure 20 by the shaft member 13, it is less likely to be displaced even when an earthquake motion acts on it. Therefore, the earthquake resistance of permanent structures constructed using the large sandbags 21 can be enhanced.

(1-2) Permanent structures can be constructed without removing the large sandbags 21 temporarily installed.
(1-3) Since the bearing pressure plates 12 arranged vertically and horizontally are separated from each other, the large sandbag 21 can be supported from the front regardless of the surface shape of the temporary structure 20 . For example, even if the height and depth of the steps formed by the large sandbag 21 are different for each step, the bearing plate 12 can be arranged according to the steps.

(Second embodiment)
As shown in FIG. 3, in the reinforcing earth wall 11 of this embodiment, a plurality of supporting pressure plates 12 arranged vertically and horizontally cover the entire surface of the temporary structure 20 to constitute the wall surface of the permanent structure. The method of fixing the bearing plate 12 and the shaft member 13 is the same as in the first embodiment shown in FIG.

When a plurality of bearing pressure plates 12 are arranged vertically and horizontally to form one wall surface, it is preferable to bury a foundation of concrete 26 under the lowest bearing pressure plate 12 . A top end of concrete 26 can also be placed on top of the uppermost bearing pressure plate 12 . If the surface of the bearing pressure plate 12 is made into a decorative surface, the appearance can be improved.

In the earth retaining method of the second embodiment, after the bearing pressure plates 12 corresponding to the multi-tiered large sandbags 21 are vertically and horizontally arranged in the back-filling process, the plurality of bearing pressure plates 12 and the temporary structure 20 are arranged vertically and horizontally. A fluid backing material 14 may be added to fill the gap. By doing so, the working efficiency of the back-filling process is improved. Since the backing material 14 formed in this manner is solidified across the plurality of bearing plates 12 , the plurality of bearing plates 12 are integrally fixed to the temporary structure 20 .

According to the reinforcing earth wall 11 and earth retaining method of the present embodiment, the following effects can be obtained in addition to the effects (1-1) and (1-2) above.
(2-1) Since the support plate 12 covers the entire surface of the temporary structure 20, the effect of suppressing deformation of the temporary structure 20 is high.

(2-2) Since the large sandbag 21 is not exposed to the outside, the temporary structure 20 is less likely to deteriorate, for example, when the sandbag breaks and the filling material flows out.
(2-3) By arranging the bearing plates 12 having the through holes 12a without gaps, the shaft members 13 can be arranged at a predetermined density regardless of the arrangement of the large sandbags 21.

(2-4) By filling the gap between the bearing plate 12 and the large sandbag 21 with the backing material 14, it is possible to form a slope composed of a plurality of bearing plates 12 on the front surface of the temporary structure 20 having steps. .

The above-described embodiment may be modified as in modification examples shown below. You may arbitrarily combine the structure included in the said embodiment, and the structure included in the following modification examples, and may arbitrarily combine the structure included in the following modification examples.

- Like the 1st modification shown in FIG. 4, and the 2nd modification shown in FIG. 5, the large-sized sandbag 21 may be arrange|positioned so that a bottom may incline downward with respect to a horizontal surface. According to this configuration, the resistance of the large-sized sandbag 21 to the back soil pressure is increased, so the stability of the temporary structure 20 is increased. In this case, the shaft member 13 may be inserted at substantially the same angle as the large-sized sandbag 21, or the large-sized sandbag 21 and the shaft member 13 may have different inclination angles with respect to the horizontal. When laying the embankment reinforcing material 24, if the portion along the large sandbag 21 is inclined along the large sandbag 21 and laid substantially horizontally in the embankment 23, it is easy to create the embankment 23 formed for each stage. .

5, when the large sandbags 21 and the shafts 13 are arranged at substantially the same inclination angle, the shafts 13 are inserted between the adjacent large sandbags 21 good too.
Below, the technical idea grasped from the embodiment mentioned above and its effect are described.

[Thought 1]
a plurality of large sandbags;
An embankment formed between the ground and the large sandbag;
a bearing plate that supports the large sandbag;
a shaft having a distal end inserted into the embankment and a proximal end fixed to the bearing plate;
a backing material that fills a gap between the bearing pressure plate and the large sandbag;
A reinforced earth wall using a large sandbag, characterized by comprising:

According to this configuration, since the bearing plate is integrated with the large-sized sandbag and the embankment by the shaft member, the bearing plate is less likely to be displaced even if seismic motion acts. Therefore, it is possible to enhance the earthquake resistance of permanent structures constructed using large-sized sandbags.

[Thought 2]
The reinforced earth wall using the large sandbags according to [Thought 1] is characterized by comprising an embankment reinforcing member extending from the large sandbag into the embankment.

According to this configuration, the seismic resistance of the temporary structure 20 increases due to bearing pressure resistance and frictional resistance generated between the embankment reinforcing material and the embankment.
[Thought 3]
The tip of the shaft member is arranged downward with respect to a horizontal plane, the length of the shaft member from the front surface of the large sandbag is L1, the length of the embankment reinforcement from the front surface of the large sandbag is L2, and The reinforced earth wall using large sandbags according to [Thought 2], characterized in that L1×cosα≧L2, where α is the inclination angle of the shaft with respect to the horizontal.

According to this configuration, the stability of the permanent structure can be enhanced by inserting the shaft into the embankment as deep as or deeper than the embankment reinforcement.
[Thought 4]
The backing material is a fluid when placed between the bearing pressure plate and the large sandbag,
A reinforced earth wall using a large sandbag according to any one of [Thought 1] to [Thought 3], wherein the solidification is performed in a state in which a gap between the bearing pressure plate and the large sandbag is filled.

According to this configuration, the space between the bearing plate and the large-sized sandbag can be filled without gaps by the flow of the backing material at the time of arrangement. When the backing material solidifies, the bearing plate and the large sandbag are integrated, and the displacement of the bearing plate is suppressed. Therefore, the earthquake resistance of the permanent structure can be enhanced.

[Thought 5]
Placing a plurality of large sandbags in front of the ground;
Embankment between the large sandbag and the natural ground;
placing a bearing plate in front of the large sandbag;
Filling a gap between the bearing pressure plate and the large sandbag with a backing material;
inserting the tip side of the shaft into the embankment;
fixing the base end side of the shaft member to the bearing plate;
An earth retaining method using a large sandbag, characterized by comprising:

According to this configuration, it is possible to obtain the same effect as that of the reinforcing earth wall.

DESCRIPTION OF SYMBOLS 11... Reinforcing earth wall, 12... Bearing plate, 12a... Through hole, 12b... Recessed part, 13... Shaft member, 13a... Screw part, 14... Backing material, 15... Insertion hole, 16... Filling material, 17... Fixing member , 18... washer, 20... temporary structure, 21... large sandbag, 22... natural ground, 23... embankment, 24... embankment reinforcing material, 25... foot protection part, 26... concrete.

Claims (9)

a plurality of large sandbags;
An embankment formed between the ground and the large sandbag;
a bearing plate arranged in front of the large sandbag so as to cover the surface of the large sandbag and supporting the large sandbag;
a shaft having a distal end inserted into the embankment and a proximal end fixed to the bearing plate;
a backing material that solidifies and fills a gap between the bearing pressure plate and the large sandbag;
with
Among the large sandbag, the embankment, and the backfill material, at least the embankment has an insertion hole through which the tip end side of the shaft member whose base end side is fixed to the bearing pressure plate is inserted,
The insertion hole is filled with a filler made of cement milk or mortar with the shaft member inserted therein,
A reinforced earth wall using large sandbags, wherein the backing material is composed of cement bentonite having a different component from the cement milk or the mortar that constitutes the filling material. a plurality of large sandbags;
An embankment formed between the ground and the large sandbag;
a bearing plate arranged in front of the large sandbag so as to cover the surface of the large sandbag and supporting the large sandbag;
a shaft that penetrates the large sandbag and has a base end fixed to the bearing plate in a state where the tip end is inserted into the embankment;
a backing material that fills a gap between the bearing pressure plate and the large sandbag;
with
Of the large-sized sandbag, the embankment, and the backfill material, at least the large-sized sandbag and the embankment have an insertion hole through which the shaft member whose base end side is fixed to the bearing plate is inserted,
The insertion hole is filled with a filler made of cement milk or mortar with the shaft member inserted therein,
A reinforced earth wall using large sandbags, wherein the backing material is composed of cement bentonite having a different component from the cement milk or the mortar that constitutes the filling material. The reinforced earth wall using large sandbags according to claim 1 or 2, further comprising an embankment reinforcement extending from the large sandbag into the embankment. The tip of the shaft member is arranged downward with respect to a horizontal plane, the length of the shaft member from the front surface of the large sandbag is L1, the length of the embankment reinforcement from the front surface of the large sandbag is L2, and The reinforced earth wall using large sandbags according to claim 3, wherein L1×cosα≧L2, where α is the inclination angle of the shaft with respect to the horizontal. The backing material is a fluid when placed between the bearing pressure plate and the large sandbag,
The reinforced earth wall using the large-sized sandbag according to any one of claims 1 to 4, wherein the reinforced earth wall is solidified in a state in which a gap between the bearing pressure plate and the large-sized sandbag is filled. The reinforced earth wall using the large-sized sandbag according to any one of claims 1 to 5, wherein the large-sized sandbag is arranged so that the bottom thereof is inclined downward with respect to a horizontal plane. Placing a plurality of large sandbags in front of the ground;
Embankment between the large sandbag and the natural ground;
placing a bearing plate in front of the large sandbag to cover the surface of the large sandbag;
Filling the gap between the bearing pressure plate and the large sandbag with a solidifying backing material;
excavating an insertion hole into which a shaft can be inserted in at least the embankment among the large sandbag, the embankment, and the backfill material;
inserting the tip side of the shaft member into the insertion hole;
fixing the base end side of the shaft member to the bearing plate;
filling a filler made of cement milk or mortar with the shaft member inserted into the insertion hole;
including
An earth retention method using a large sandbag, wherein the backfill material is composed of cement bentonite having a different component from the cement milk or the mortar that constitutes the filling material. Placing a plurality of large sandbags in front of the ground;
Embankment between the large sandbag and the natural ground;
a primary step having
placing a bearing plate in front of the large sandbag to cover the surface of the large sandbag;
Filling a gap between the bearing pressure plate and the large sandbag with a backing material;
excavating an insertion hole into which a shaft can be inserted in at least the large-sized sandbag and the embankment among the large-sized sandbag, the embankment, and the backfill material;
inserting the tip side of the shaft member into the insertion hole;
fixing the proximal end of the shaft with the distal end inserted into the insertion hole to the support plate;
filling a filling material composed of cement milk or mortar with the shaft member inserted into the insertion hole;
including
An earth retention method using a large sandbag, wherein the backfill material is composed of cement bentonite having a different component from the cement milk or the mortar that constitutes the filling material. The earth retention method using the large-sized sandbag according to claim 7 or 8, wherein the large-sized sandbag is placed so that the bottom portion thereof is inclined downward with respect to a horizontal plane.

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