JP5418369B2 - Filling reinforcement structure - Google Patents

Description

  The present invention relates to a reinforcement structure for embankments extending long along rivers, rivers such as rivers, railway embankments, roads, railways, and the like.

  Conventionally, as reinforcement for embankments of rivers and other embankments, the embankment slope is covered with a material with low water permeability or imperviousness, or the embankment is extended to the bottom edge of the embankment slope. It is known to construct a steel sheet pile wall in the ground along the current direction (length direction).

  However, the slope covering does not reinforce the embankment itself and cannot prevent the embankment (dam body) from being destroyed when a large external force is applied to the embankment during an earthquake or flood. In addition, the embankment cannot be prevented from becoming unstable due to softening or deformation of the foundation ground due to liquefaction during an earthquake. Furthermore, in a river dike, it is not possible to prevent water leakage to the inside of the dike body through a highly permeable layer at the bottom of the embankment. Therefore, in order to stabilize the foundation ground and prevent the water leakage, it is necessary to dispose the steel sheet pile wall at the butt portion as described above, but when this steel sheet pile wall is used, Even if the foundation portion is reinforced, the embankment portion is not reinforced, and for example, it is not possible to prevent the embankment portion from collapsing when water overflows during a flood.

  Therefore, between the shoulders that are the upper ends of the slopes on the left and right of the embankment structure (front and back or outside in the case of a dike), and at the top edge (top of the embankment) between these shoulders, It has been proposed to construct a steel sheet pile wall extending from the support layer to the height of the top of the embankment along the length of the embankment (see, for example, Patent Document 1). Moreover, in this patent document 1, while constructing a steel sheet pile wall in the vicinity of the both shoulders of the front and back (outside and inside), respectively, the steel sheet pile wall is provided in two rows at the center of the embankment structure, and in the embankment It has been proposed to connect the upper ends of two rows of steel sheet pile walls with a connecting member such as a tie rod.

By constructing steel sheet pile walls in two rows from the shoulder of the embankment to the top edge in this way, double steel sheet pile cut-off parts are constructed in the embankment, forming a structurally solid core and reinforcing the embankment can do. This makes it possible to cope with various external force conditions during floods and earthquakes. For example, it is possible to cope with infiltration, washing, overtopping during floods, and inertial forces and liquefaction of foundation ground during earthquakes.
In other words, when used as a river embankment, the height of the embankment of the embankment can be maintained by two rows of steel sheet pile walls in the event of a flood or earthquake. The embankment can be prevented from collapsing. Even when used as a road or railway embankment, by using the part between the two rows of steel sheet pile walls as a road or railroad, it is possible to prevent the road and railroad from collapsing and to facilitate restoration work. It becomes.

JP 2003-13451 A

  By the way, the reason why the double steel sheet pile walls are connected by the connecting member such as a tie rod as described above is to prevent a large deformation of the upper part of the steel sheet pile wall when an external force acts on the steel sheet pile wall. However, because the tie rods are arranged near the top of the embankment, the ground surface between the double steel sheet piles at the top of the embankment is slightly due to liquefaction during an earthquake or flooding during a flood. If it sinks or is scraped off slightly, the tie rod near the top surface of the top will be exposed. Since the tie rods are arranged at approximately equal intervals in the length direction of the embankment, when the top of the embankment is used as a road, the exposed tie rod becomes an obstacle and passes over the top of the embankment by vehicle. It becomes difficult to do. In addition to road embankments, the embankment for river embankments may be used as roads and for emergency vehicles even if they are not regularly used as vehicle roads. It may be used as a passageway, and confusion will occur if the vehicle cannot pass through the top of the embankment that will become a dike after an earthquake or flood.

  Moreover, work which connects the steel sheet pile wall arrange | positioned doubly at intervals with a tie rod requires time and work time. In embankment reinforcement with double steel sheet pile walls, the construction period required to build steel sheet pile walls by placing steel sheet piles sequentially on the embankment is relatively short. The connecting work becomes an obstacle to shortening the construction period.

  The present invention provides a vehicle at the top of an embankment after an earthquake or a flood while preventing deformation of the underground steel wall body when reinforcing the embankment with an underground steel wall body such as a double steel sheet pile wall. It is an object of the present invention to provide an embankment reinforcement structure that enables the passage of the material and simplifies the reinforcement work and shortens the construction period.

In order to solve the above-mentioned problem, the embankment reinforcing structure according to claim 1 is provided with underground steel wall bodies in at least two rows along the continuous direction of the embankment within the range of the approximate top end of the continuous embankment. And
Each of the underground steel wall bodies has flexibility and is connected to a planar reinforcing material disposed in the ground,
Each of the planar reinforcing members is connected to only one of the underground steel wall bodies without being bridged between the adjacent underground steel wall bodies,
In each of the underground steel wall bodies, the planar reinforcing material is connected to the side between the adjacent underground steel wall bodies,
A plurality of the planar reinforcement members are arranged side by side along the continuous direction of the underground steel wall body,
One of the underground steel wall bodies and the other of the underground steel wall bodies are arranged in a staggered manner so as to be staggered, and one of the underground steel wall bodies has a planar reinforcement. A planar reinforcing material of the other underground steel wall body is disposed in the space between the materials .

  In the first aspect of the present invention, since the underground reinforcing member in the ground is connected to the underground steel wall body, an external force acts on the underground steel wall body to oppose the planar reinforcing material. In the case of deformation to the side, the planar reinforcing material is pulled. At this time, frictional resistance of earth and sand acts on the planar reinforcing material, and deformation of the underground steel wall body is prevented.

Therefore, it is possible to prevent the steel sheet pile wall from being deformed without connecting the underground steel wall body formed of two rows of steel sheet pile walls with a connecting member such as a tie rod as in the prior art.
In this case, it is easier to attach the planar reinforcing material to each steel sheet pile wall than to connect the two rows of steel sheet pile walls with a connecting member, which can reduce the amount of work and the work period. it can.

  In addition, even if the earth and sand at the top of the embankment sinks or is scraped off due to an earthquake or flood, the planar reinforcing material is flexible and adjacent underground steel walls Since it is not bridged between the bodies and is cantilevered, it will not be exposed on the earth and sand when it sinks in the earth or sediment, or even if it is exposed, it will bend along the top surface of the earth and sand. It is unlikely that the vehicle travels like a tie rod, and an emergency vehicle can be passed over the top of the embankment immediately after an earthquake or flood.

  Here, the connection between the underground steel wall body and the planar reinforcing member includes various connection structures such as locking, coupling, and fixing. However, in the connection structure between the underground steel wall body and the planar reinforcing material, it is necessary to have a structure that pulls the planar reinforcing material when the underground steel wall body is displaced away from the planar reinforcing material. There is. Further, another member may be interposed between the underground steel wall body and the planar reinforcing material and connected.

In the embankment reinforcement structure according to claim 2, the reinforcing member is connected to the inside of the underground steel wall bodies arranged in two rows, and the two rows of underground steel wall bodies are separated from each other. It is possible to prevent deformation in the direction.
That is, the same effect as when two rows of underground steel wall bodies are connected by tie rods can be obtained.
In addition, since the underground steel wall body is basically continuous for a long time, when the size of the planar reinforcing material is limited, a plurality of planar reinforcing materials are added to the underground steel wall body. In such a case, the planar reinforcing members are arranged at intervals in the continuous direction of the underground steel wall body (the continuous direction of the embankment).
At this time, it is also possible to alternately arrange the planar reinforcing materials so as to be staggered between adjacent underground steel wall bodies, and with such an arrangement, each adjacent underground steel wall body Since the connected planar reinforcing material does not overlap in the depth direction, the depth at which the planar reinforcing material is disposed can be reduced, and the reinforcement work can be simplified and the construction period can be shortened. Also, even if the planar reinforcement members connected to each of the two rows of underground steel wall bodies are lengthened, the planar reinforcement members do not overlap in the depth direction. It is possible to make up for the reduced area of the planar reinforcing material by increasing the length perpendicular to the wall-making body and spacing it in the length direction of the underground steel wall-making body.

The embankment reinforcing structure according to claim 3 is the invention according to claim 1 or 2, wherein the planar reinforcing members connected to each of the adjacent underground steel wall bodies are arranged in the depth direction. It is characterized by being.

  In the reinforcement structure of the embankment of Claim 3, the surface connected to a steel wall body in each place by arrange | positioning each planar reinforcing material of the underground steel wall body adjacent to each other in the depth direction. While increasing the area of the shape reinforcing material, it is possible to increase the length of the underground steel wall body along the orthogonal direction, and to increase the resistance to deformation of the underground steel wall body. .

  In order to maintain each sheet reinforcement in its current position between the sheet reinforcements that overlap each other when the sheet reinforcements of steel walls in each location are stacked in the depth direction as described above In order to cause the frictional resistance (pullout resistance) to act, it is necessary to arrange earth and sand with a certain thickness in the depth direction between the overlapping sheet reinforcing materials. As a result, when planar reinforcing materials are connected to adjacent underground steel wall bodies in the depth direction with the same number of steps, the planar reinforcing materials of adjacent underground steel wall bodies are overlapped in the depth direction. If not, the depth of the lowermost planar reinforcing material becomes shallower than when stacked in the depth direction, and the installation work of the planar reinforcing material becomes easier. Here, when installing the planar reinforcement, it is necessary to excavate between the two rows of underground steel wall bodies 2 to the installation position of the planar reinforcement, and the installation position of the planar reinforcement is shallow. By doing so, the amount of work required for excavation can be reduced.

The embankment reinforcing structure according to claim 4 is the invention according to any one of claims 1 to 3 , wherein the planar reinforcing material is formed in a plurality of steps in the depth direction of the underground steel wall body. It is provided.

In the embankment reinforcing structure according to claim 4 , not only the area of one sheet reinforcing member connected to the underground steel wall body, but also the number of steps (number of sheets) arranged along the depth direction. Also, the strength for preventing deformation can be adjusted. That is, the resistance of the planar reinforcing material against deformation of the underground steel wall body can be adjusted by the number of steps in the depth direction of the planar reinforcing material. Therefore, even if the space between adjacent underground steel wall bodies is narrow and a plane reinforcing material with a large area cannot be arranged between these underground steel wall bodies, deformation of the underground steel wall bodies is prevented. can do.

The embankment reinforcement structure according to claim 5 is the invention according to any one of claims 1 to 4 , wherein the underground steel wall body is attached in a vertical direction on the side where the planar reinforcing material is attached. Is provided side by side in the length direction of the underground steel wall body,
The planar reinforcing material is formed in a band shape, and a rod-shaped member is provided at one end,
Both end portions of the rod-shaped member are respectively locked in the locking grooves so as to be movable in the vertical direction,
The planar member in a rolled state is developed and laid.

In the invention according to claim 5 , as the work for constructing the embankment reinforcement structure, for example, steel sheet piles are continuously placed in two rows so that underground steel wall bodies are provided in two rows. , Excavating the portion between these two rows of underground steel wall bodies to the position where the lowermost planar reinforcing material is installed, laying the planar reinforcing material on the excavated portion, and the planar reinforcing material To one of the two rows of underground steel walls. Here, while inserting the rod-shaped member provided in the one end part side of the planar reinforcement in the state wound in the shape of a roll in the locking groove provided in the underground steel wall body, it drops down below ( The planar reinforcing material is placed on the ground of the excavated portion. By deploying the planar reinforcing material wound in this state, the planar reinforcing material is arranged. Moreover, the planar reinforcing material is in a state of being connected to the underground steel wall body through a rod-like member locked in the locking groove.
This improves the workability of laying the planar reinforcing material on the excavated ground and connecting it to the underground steel wall body, thereby shortening the construction period.

According to the present invention, when the embankment is reinforced with two rows of underground steel wall bodies, it is not necessary to connect the two rows of underground steel wall bodies with tie rods or the like. Workability can be improved because it is only necessary to attach an educational material.
In addition, since the planar reinforcing material is flexible and is not bridged between adjacent underground steel wall bodies, the top end part may sink slightly or be scoured slightly. Even if it exists, since a planar reinforcement is bent and arrange | positioned in the ground or on the ground without protruding, it is possible to pass vehicles such as emergency vehicles.

It is a schematic sectional drawing which shows the reinforcement structure of the embankment which concerns on embodiment of this invention. It is a schematic sectional drawing which shows the modification of the reinforcement structure of the said embankment. (A) is a schematic top view except the embankment which shows another modification of the reinforcement structure of the said embankment, (b) is a schematic sectional drawing which shows another modification of the reinforcement structure of the said embankment. (A) is the schematic plan view except the embankment which shows another modification to the reinforcement structure of the said embankment, (b) is a schematic sectional drawing which shows another modification of the reinforcement structure of the said embankment. It is a principal part top view except the embankment which shows another modification of the reinforcement structure of a embankment. It is a principal part top view except the embankment which shows another modification of the reinforcement structure of a embankment. It is a principal part top view except the embankment which shows another modification of the reinforcement structure of a embankment. It is a principal part perspective view which shows the state in the middle of construction of the modification shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the embankment reinforcement structure of this example is for reinforcing embankments such as river embankments and road / railway embankments. Slopes 1 a are formed on the left and right sides of the embankment 1.
In the reinforcing structure of the embankment 1, a steel sheet pile wall in which a steel sheet pile 3 (including a steel pipe sheet pile: various steel sheet piles 3a to 3c are shown in FIGS. 5 to 8) is connected within the range of the approximate top end 1c of the embankment 1. The underground steel wall body 2 which consists of is installed. Note that the range of the approximate top end 1c also includes the shoulder 1b portion that is the upper end of the slope 1a slightly outside the top end 1c.

  The steel sheet pile 3 that constitutes the underground steel wall body 2 penetrates the embankment 1 and the foundation ground directly below it, has a depth to be embedded in the supporting ground, and is in a continuous direction (length direction) of the embankment 1. It is continuously installed along. The head portion (upper end portion) of the underground steel wall body 2 is located at a height near the height of the top end 1 c of the embankment 1. In the reinforcement structure of the embankment 1, a structural skeleton portion 5 is formed in the embankment 1. The structural skeleton 5 is made of ground that is closed by underground steel wall bodies 2 and 2 provided in two rows.

In this embankment reinforcement structure, when a large external force is applied due to a flood, an earthquake, etc., there is a possibility that the upper part of the two rows of underground steel wall bodies 2, 2 may be deformed. There is a possibility that the walls 2 and 2 are deformed to the outside, that is, to the near slope 1a side. Therefore, in this example, in order to prevent the deformation of the underground steel wall bodies 2, 2, a planar shape that is arranged in the ground and connected to the upper ends of the underground steel wall bodies 2, 2. A reinforcing material 7 is provided.
In the two or more rows of underground steel wall bodies 2, the planar reinforcing member 7 is disposed on the side between the adjacent underground steel wall bodies 2, that is, on the inner side.

This planar reinforcing material 7 is not connected in a state where it is bridged over both adjacent two rows of underground steel wall bodies 2, and each planar reinforcing material 7 is composed of two rows of underground steel. Only one of the wall-making bodies 2 and 2 is connected.
That is, each middle steel wall body 2 is connected to a sheet reinforcing member 7, but each sheet reinforcing member 7 is connected to only one underground steel wall member 2, The shape reinforcing material 7 is not in a state of connecting adjacent underground steel wall bodies 2.
Moreover, although the planar reinforcing material 7 is continuously arrange | positioned along the length direction of the underground steel wall body 2, for example, the planar reinforcing material 7 of a predetermined shape is disposed on the underground steel wall body 2. In the case where a plurality of the steel wall bodies 2 are connected in the length direction, there may be a space between the steel wall bodies 2 in each location, and the planar reinforcing member 7 is in the length direction of the underground steel wall body 2. It is not necessary to be arranged completely continuously.

  The planar reinforcing material 7 is formed, for example, by forming a synthetic resin material into a sheet shape and laying it in the soil to reinforce the embankment or the ground, and various materials generally called geosynthetics or geotextiles have been developed. It is desirable to have flexibility and necessary tensile strength. In this example, a grid-like (lattice-like) thing called a geogrid among those called a geotextile is used.

  As the geogrid, high-density polyethylene, polypropylene, or the like can be used as a lattice-like product made of synthetic resin, and polyester fiber or aramid fiber can be used as a net-like product made of chemical fiber. In addition, as long as it has flexibility, excellent tensile characteristics and creep characteristics, and generates a large frictional resistance with the earth and sand, it is not particularly limited to the above-mentioned materials, mesh shape or grid shape. . However, it is preferable that the structure allows water to pass through.

  Such a surface reinforcing material 7 is basically a material for tensile reinforcement of earth and sand such as embankment by strongly restraining soil particles having poor tensile resistance to the mesh of the geogrid. In this example, the surface reinforcing material 7 in the ground has a high frictional resistance against the earth and sand, and the pulling resistance is high. It is used to prevent deformation of the underground steel wall body 2 by connecting the underground reinforcing member 7 to the underground steel wall body 2. The planar reinforcing material 7 can sufficiently prevent the deformation of the underground steel wall body 2 even if the two rows of the underground steel wall bodies 2 are not configured to be connected by, for example, tie rods at predetermined intervals. can do.

Various arrangements of the planar reinforcing material 7 when the planar reinforcing material 7 is attached to the underground steel wall body 2 can be considered. In the example shown in FIG. Each of the bodies 2 is provided with a plurality of (two in FIG. 1) planar reinforcing members 7 in the depth direction (vertical direction).
Moreover, the length orthogonal to the underground steel wall body 2 of the planar reinforcing material 7 is longer than 1/2 of the distance between the two rows of underground steel wall bodies 2, and one underground The planar reinforcing material 7 connected to the steel wall body 2 and the planar reinforcing material 7 connected to the other underground steel wall body 2 are arranged so as to overlap in the depth direction.

  As described above, by disposing a plurality of planar reinforcing members 7 in the depth direction on the underground steel wall body 2, resistance to deformation of the underground steel wall body 2 can be increased. Therefore, the number of the planar reinforcing members 7 can be determined in accordance with the resistance required to prevent the deformation of the underground steel wall body 2. That is, if the underground steel wall body 2 can be sufficiently prevented from being deformed by the one-step planar reinforcing material 7 in the depth direction, the planar reinforcing material 7 may be arranged by one step in the depth direction. If the deformation of the underground steel wall body 2 cannot be sufficiently prevented by one stage, the number of stages may be two, or three or more.

  In addition, when the planar reinforcing members 7 are horizontally disposed by overlapping the planar reinforcing members 7 respectively connected to the adjacent underground steel wall bodies 2 in the depth direction, the planar reinforcing members are disposed. 7 can be the distance between the maximum two rows of underground steel wall bodies 2, and the resistance to deformation of the underground steel wall body 2 by the one-stage planar reinforcing material 7 is increased. Can do.

However, in this case, all the sheet reinforcing members 7 connected to the two rows of underground steel wall bodies 2 are overlapped in the depth direction, and earth and sand are placed between the sheet reinforcing members 7. Since it is necessary to arrange | position with sufficient thickness, the arrangement | positioning depth of the lowermost planar reinforcing material 7 becomes deep, and in order to arrange the planar reinforcing material 7, two rows of underground steel wall bodies 2 are arranged. The excavation depth required when excavating the space between them becomes deep.
Note that the uppermost planar reinforcing material 7 is provided with earth and sand having a minimum required depth on the upper side, and is disposed at a position slightly lower than the top end 1c.
Moreover, when the deformation | transformation of sufficient underground steel wall body 2 cannot fully be prevented only by the planar reinforcement 7, the two rows of underground steel wall 2 in which the planar reinforcement 7 is arrange | positioned. At the upper end of the intermediate portion, when the planar reinforcing material 7 is disposed and the earth and sand are backfilled, a cement-based solidifying material (ground improvement cement) may be mixed with the earth and sand to be backfilled to improve the ground. Thereby, the drawing-out resistance of the planar reinforcing material 7 can be increased, and the force for suppressing the deformation of the underground steel wall body 2 can be increased.

  The method of constructing such embankment reinforcement structure is, for example, an underground steel wall made of steel sheet pile walls by driving steel piles into the embankment while connecting them in two rows when reinforcing an existing embankment. Build body 2. In addition, after the underground steel wall 2 is constructed, the soil between them is excavated. At this time, excavation is performed up to the position where the lowermost planar reinforcing material 7 is arranged, and the planar reinforcing material 7 is spread and arranged at the bottom of the excavated portion. Connect to the steel wall 2. At the time of connection, it is only necessary to be engaged with or connected to the underground steel wall body 2 so as not to come out when the planar reinforcing member 7 is pulled.

  Next, the earth and sand are backfilled to the arrangement position of the sheet reinforcing material 7 that is the second from the bottom, the sheet reinforcing material 7 is spread on the backfilled earth and sand, and this sheet reinforcing material 7 is placed in the other ground. Connect to the steel wall 2. By repeating these operations, all the planar reinforcing members 7 are arranged in the ground and connected to the underground steel wall 2.

  In this embankment reinforcement structure, the embankment 1 is reinforced by two rows of underground steel wall bodies 2 so that, for example, the underground steel walls that are opposed to each other with a distance corresponding to the width of the top end 1c. Since the structural skeleton 5 is closed and restrained by the body 2 to ensure high stability, a large inertial force may act during a large-scale earthquake or the foundation ground may soften due to liquefaction or the like. Even if it exists, since it has the capability to maintain a form, collapse of the top edge part of the embankment 1 is prevented at least. In addition, when used as a river dike, the embankment height is maintained even if liquefaction occurs during an earthquake or flooding occurs during a flood, preventing collapse of the embankment (river collapse). Can do.

  In addition, the deformation of the underground steel wall body 2 is not connected to the adjacent underground steel wall body 2 with a connecting member such as a tie rod at every predetermined distance, but to the intermediate steel wall body 2 in various places. 7 is connected, the work can be simplified and the work period can be shortened. The planar reinforcing member 7 is connected, for example, by attaching a locking member (connecting member) to each of the underground steel wall body 2 and the planar reinforcing member 7 and connecting these locking members (connecting member). ) May be configured to engage (couple) each other, and the planar reinforcing material 7 can be connected to the underground steel wall body 2 with a simple structure.

In addition, the tie rod will not be exposed even if the top and bottom soils sink or disappear due to subsidence due to liquefaction during an earthquake or scouring due to overflowing water during a flood. Therefore, the planar reinforcing member 7 having only one side and connected to the underground steel wall body 2 sinks together with the earth or sand and is arranged in a state along the earth and sand surface.
Here, even if the portion between the two rows of underground steel wall bodies 2 is slightly lowered, for example, there is a high probability that emergency vehicles can pass, and as an emergency vehicle passage after an earthquake or flood, The top part of the embankment can be used, but if there is a tie rod directly under the top, the tie rod is exposed and placed in a hurdle on the lowered top end 1c, making it impossible for the vehicle to pass. .

On the other hand, by using the planar reinforcing member 7 for reinforcing the underground steel wall 2 as described above, the probability that emergency vehicles can pass is increased. Thereby, the mobility of the emergency vehicle at the time of a disaster can be ensured.
Moreover, in order to construct the planar reinforcement 7 as described above by connecting the planar reinforcement 7 to the upper end portion of the underground steel wall 2, two rows of underground steel walls are provided. The depth when excavating between the bodies 2 becomes shallow, so that the workability of reinforcing the embankment can be improved and the work period can be shortened.

Below, the modification of arrangement | positioning of the planar reinforcement 7 connected to the underground steel wall body 2 is demonstrated with reference to FIGS.
In the following modification, only the arrangement of the planar reinforcing material 7 is different, and the other configurations are the same as those in the above-described example.
In the modification shown in FIG. 2, planar reinforcing members 7 are arranged in a plurality of stages (two stages) in the depth direction in each of the two rows of underground steel wall bodies 2. Moreover, the length along the direction orthogonal to the underground steel wall body 2 of the planar reinforcing material 7 is 1/2 or less of the distance between the adjacent underground steel wall bodies 2. Thereby, the planar reinforcement 7 connected to one underground steel wall body 2 and the planar reinforcement 7 connected to the other underground steel wall body 2 do not overlap in the depth direction. It has become.

  In such an arrangement of the planar reinforcement member 7, the area of the planar reinforcement member 7 is reduced and the length from the underground steel wall body 2 is shortened with respect to the above example. Although the generated frictional resistance is reduced, the number of the planar reinforcing materials 7 that overlap each other is reduced, and the planar reinforcing materials 7 can be disposed at a shallow position. Thereby, when arrange | positioning the planar reinforcement member 7, it becomes possible to make the excavation depth shallow when excavating between the underground steel wall bodies 2 adjacent, and the operation | work which installs the planar reinforcement member 7 It is possible to improve the workability and shorten the construction period. Therefore, according to the frictional resistance required for the planar reinforcing material 7, either the arrangement of the planar reinforcing material 7 in FIG. 1 or the arrangement of the planar reinforcing material 7 in FIG. 2 may be selected. Good.

In the modification shown in FIGS. 3A and 3B, the planar reinforcing material 7 is not continuously arranged along the length direction of the underground steel wall body 2. The rectangular planar reinforcing members 7 are arranged in a row at intervals in the longitudinal direction of the underground steel wall body 2. In this example, the number of steps in the depth direction of the planar reinforcing member 7 is one.
In this example, the width along the length direction of the underground steel wall body 2 of the rectangular planar reinforcing member 7 and the length direction of the underground steel wall body 2 of the planar reinforcing material 7 are aligned. Regarding the relationship with the interval, the interval is slightly longer than the width of the planar reinforcing member 7.

  Moreover, in two adjacent underground steel wall bodies 2, the shape and arrangement of the planar reinforcing material 7 of one underground steel wall body 2 and the planar reinforcement of the other underground steel wall body 2 are provided. The shape and arrangement of the material 7 are the same, but the planar reinforcing material 7 is planar so that the one underground steel wall 2 and the other underground steel wall 2 are staggered. The reinforcing members 7 are arranged so as to be shifted from each other, and the planar reinforcing member 7 of the other underground steel wall body 2 is disposed in the space between the planar reinforcing members 7 of the first underground steel wall body 2. Is arranged.

Accordingly, the planar reinforcing material 7 connected to one underground steel wall body 2 and the underground steel wall body 2 of the planar reinforcing material 7 connected to the other underground steel wall body 2 are used. Even if the length in the orthogonal direction is ½ or more of the distance between the underground steel wall bodies 2 adjacent to each other, the planar reinforcing members 7 do not overlap each other.
Thereby, even if it uses the long sheet reinforcement 7 in the direction orthogonal to the underground steel wall 2 so as to increase the frictional resistance with the earth and sand, the sheet reinforcement 7 is prevented from overlapping, The excavation depth when laying the planar reinforcing material 7 can be reduced, and workability can be improved and the construction period can be shortened.

  In the modification shown in FIGS. 4A and 4B, the planar reinforcement 7 is formed along the length direction of the underground steel wall body 2 in the same manner as the modification shown in FIG. 3. Are not continuously arranged, and the rectangular planar reinforcing members 7 are arranged in a line at intervals in the longitudinal direction of the underground steel wall body 2. Moreover, the width along the length direction of the underground steel wall body 2 of the rectangular planar reinforcement member 7 and the interval along the length direction of the underground steel wall body 2 of the planar reinforcement member 7 The distance is slightly longer than the width of the planar reinforcing member 7.

  Moreover, in two adjacent underground steel wall bodies 2, the shape and arrangement of the planar reinforcing material 7 of one underground steel wall body 2 and the planar reinforcement of the other underground steel wall body 2 are provided. The shape and arrangement of the material 7 are the same, but the arrangement of the planar reinforcing material 7 is alternated between one underground steel wall body 2 and the other underground steel wall body 2. Planar reinforcement of the other underground steel wall body 2 is arranged in the space between the planar reinforcement members 7 of one underground steel wall body 2 in which the planar reinforcement members 7 are displaced. A material 7 is arranged.

Further, in the example shown in FIG. 3, only one level of the sheet reinforcing material 7 is arranged in the depth direction, whereas in the example shown in FIG. 4, the sheet reinforcing material is vertically two-staged in the depth direction. A material 7 is arranged. Further, the planar reinforcing member 7 is disposed obliquely so as to face downward as it goes from the base end portion connected to the underground steel wall body 2 toward the distal end portion.
In this example, the planar reinforcing material 7 made of underground steel can be installed with respect to the limited interval between the two rows of underground steel wall bodies 2 by arranging the planar reinforcing material 7 diagonally. The length perpendicular to the wall 2 can be increased, thereby increasing the frictional resistance of the planar reinforcing member 7 and increasing the force for suppressing the deformation of the underground steel wall 2.

The following modifications shown in FIGS. 5 to 8 are detailed examples of steel sheet piles 3 (including steel pipe sheet piles) constituting the underground steel wall body 2 and planar reinforcement to the underground steel wall body 2. A detailed example of the locking method of the material 7 is shown, and a detailed example of the construction method is shown. In these examples shown in FIGS. 5 to 8, the arrangement of the planar reinforcing material 7 and the like can be the same as those in the above example shown in FIG. 1 and the modifications shown in FIGS. 2 to 4.
In the modification shown in FIG. 5, a steel sheet pile wall made of a U-shaped steel sheet pile 3 a is used as a steel sheet pile wall constituting the underground steel wall body 2, and the underground steel wall body 2 is a U-shaped steel. It is comprised by connecting the sheet pile 3a.
In this modification, U-shaped steel sheet piles for each predetermined number of U-shaped steel sheet piles 3a projecting in a mountain shape on the side facing the underground steel wall body 2 adjacent to each other. The web portion of the cut T-section steel 21 (T-section steel formed by cutting the H-section steel in half with a web) is welded to the web portion 3a. Each of the U-shaped steel sheet pile 3a and the T-shaped steel 21 is arranged in parallel in the axial direction. A locking groove 22 is formed between the web of the U-shaped steel sheet pile 3a and the flange of the cut T-shaped steel 21 welded to the web. The locking groove 22 is formed along the axial direction of the U-shaped steel sheet pile 3a, that is, the vertical direction.

Of these locking grooves 22, the rod-shaped member 71 in which one end of a strip-like (long rectangular) planar reinforcing material 7 is fixed to two opposing locking grooves 22 of the adjacent cut T-shaped steel 21. The left and right ends are locked so as to be movable up and down. The planar reinforcing member 7 having one end fixed to the rod-like member 71 engaged with the underground steel wall body 2 through the locking groove 22 is connected to the underground steel wall 2 adjacent to the underground steel wall body 2. It is spread and arranged on the wall-making body 2 side.
In the modification shown in FIG. 6, the steel sheet pile constituting the underground steel wall body 2 in the modification shown in FIG. 5 is not the U-shaped steel sheet pile 3a but the hat-shaped steel sheet pile 3b, and the locking groove 22 is formed. The structured steel is a structure in which two L-shaped steels (angle members) 24 are welded from a cut T-shaped steel 21 to an H-shaped steel 23.

In this example, the flange of the H-section steel 23 is welded to the crest side of the web for every predetermined number of hat-shaped steel sheet piles 3b. Further, a gap slightly wider than the diameter of the rod-shaped member is provided between the H-shaped steel 23 and the flange on the side not welded to the hat-shaped steel sheet pile 3b, and the L-shaped steel is provided on both sides of the web of the H-shaped steel 23. 24 is welded. Between the flange of the L-shaped steel 24 and the H-shaped steel 23 is the locking groove 22, and the end of the rod-shaped member 71 is vertically moved in the locking groove 22 as in the modification shown in FIG. It is movably locked.
In the modification shown in FIG. 6, as in the modification shown in FIG. 5, the underground steel wall body adjacent to the planar reinforcing member 7 locked to the underground steel wall body 2 via the rod-shaped member 71 is used. It is in a state of being expanded toward 2.

In the modification shown in FIG. 7, a steel pipe sheet pile 3c is used as a steel sheet pile constituting the underground steel wall body 2 instead of the U-shaped steel sheet pile 3a of the modification shown in FIG.
A pipe joint 3d and a T-shaped joint 3e are welded to the steel pipe sheet pile 3c at positions facing each other (positions 180 degrees apart) to form a so-called PT joint steel pipe sheet pile. In this example, a cut T-shaped steel 3f having the same shape as the T-shaped joint 3e is welded at a position 90 degrees away from each of the joints 3d and 3e, and the cut T-shaped steel 3f and the outer peripheral surface of the steel pipe sheet pile 3c are used. The locking groove 22 is formed, and the end of the rod-like member 71 similar to the modification shown in FIG. 5 is locked.
In the modified example shown in FIG. 7, as in the modified example shown in FIG. 5, the underground steel wall body adjacent to the planar reinforcing member 7 that is locked to the underground steel wall body 2 via the rod-like member 71 is used. It is in a state of being expanded toward 2.

The construction method of the embankment reinforcement structure in the modified examples shown in FIGS. 5 to 7 will be described taking the case of the steel pipe sheet pile 3c shown in FIGS. 7 and 8 as an example.
As shown in FIGS. 7 and 8, when steel pipe sheet piles 3c (steel sheet piles 3) are placed in two rows on the embankment 1, a section steel such as a cut T-section steel 3f constituting the locking groove 22 is preliminarily formed. The steel pipe sheet pile 3c (steel sheet pile 3) is welded, and the steel pipe sheet pile 3c to which the shape steel is welded is placed on the embankment 1 to construct two rows of underground steel wall bodies 2.

Next, the earth and sand between the two rows of underground steel wall bodies 2 of the embankment 1 are excavated to a depth at which the lowermost planar reinforcing material 7 is disposed.
Next, the rod-like member 71 is fixed to the one side edge portion side, and the planar reinforcing material 7 wound around the other side edge portion side into a roll shape is locked to the underground steel wall body 2. The planar reinforcing material 7 is fixed to a rod-like member 71 in a factory or the like, and is wound in a roll shape and conveyed to the site. Further, the core material 72 may be fixed to the other side edge portion of the planar reinforcing material, and the planar reinforcing material 7 may be wound in a roll shape with the core material 72 as the central axis.

Both ends of the rod-shaped member 71 to which the roll-shaped planar reinforcing material 7 is fixed are inserted into the locking groove 22 from the upper end side of the underground steel casing 2, and the rod-shaped member 71 and the roll-shaped planar reinforcement are inserted. The material 7 is suspended to the bottom of the excavated part.
Next, the roll-shaped planar reinforcing material 7 is developed. That is, the planar reinforcing material 7 is spread in a planar shape. In this case, for example, the planar reinforcing material 7 can be developed by pulling the core material 72 with a heavy machine or the like.

The earth and sand are backfilled on the spread sheet reinforcing material 7. At this time, in the case where a plurality of planar reinforcing materials 7 are arranged in the depth direction, the ground reinforcing material 7 is backfilled to the height position where the planar reinforcing materials 7 are arranged, and then as described above. Is fixed to the underground steel housing 2 and deployed. This is repeated by the number of arrangement steps in the depth direction of the planar reinforcing material 7.
According to the construction method of the embankment reinforcement structure, it becomes easy to lock the planar reinforcing member 7 to the underground steel casing 2 and to lay the planar reinforcing member 7.

  The planar reinforcing material 7 can be appropriately selected and used from the so-called geosynthetics or geotextile including the above-mentioned geogrid. Moreover, the steel sheet pile 3 used for the underground steel wall body 2 can use Z-shaped steel sheet pile etc. other than U-shaped steel sheet pile 3a, hat-shaped steel sheet pile 3b, and steel pipe sheet pile 3c.

DESCRIPTION OF SYMBOLS 1 Embankment 1c Top edge 2 Underground steel wall 7 Planar reinforcement 22 Locking groove 71 Bar-shaped member

Claims (5)

Underground steel wall bodies are provided in at least two rows along the continuous direction of the embankment within the range of the approximate top edge of the continuous embankment,
Each of the underground steel wall bodies has flexibility and is connected to a planar reinforcing material disposed in the ground,
Each of the planar reinforcing members is connected to only one of the underground steel wall bodies without being bridged between the adjacent underground steel wall bodies,
In each of the underground steel wall bodies, the planar reinforcing material is connected to the side between the adjacent underground steel wall bodies,
A plurality of the planar reinforcement members are arranged side by side along the continuous direction of the underground steel wall body,
One of the underground steel wall bodies and the other of the underground steel wall bodies are arranged in a staggered manner so as to be staggered, and one of the underground steel wall bodies has a planar reinforcement. A reinforcing structure for embankment, wherein a planar reinforcing material of the other underground steel wall body is disposed in the space between the materials . 2. The embankment according to claim 1 , wherein the planar reinforcing material is disposed obliquely so as to be directed downward from a proximal end portion connected to the underground steel wall body toward a distal end portion. Reinforcement structure. Reinforcing structure embankment according to claim 1 or 2, characterized in that each of the connected planar reinforcement of the underground steel wall adjacent are arranged to overlap in the depth direction. The reinforcing structure for embankment according to any one of claims 1 to 3 , wherein the planar reinforcing material is provided in a plurality of stages in the depth direction of the underground steel wall body. A locking groove along the vertical direction is provided side by side in the length direction of the underground steel wall body on the side on which the planar reinforcing material of the underground steel wall body is attached,
The planar reinforcing material is formed in a band shape, and a rod-shaped member is provided at one end,
Both end portions of the rod-shaped member are respectively locked in the locking grooves so as to be movable in the vertical direction,
The embankment reinforcement structure according to any one of claims 1 to 4 , wherein the planar member in a rolled state is developed and laid.

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