Embankment reinforcement structure, and construction method for embankment reinforcement structure

Abstract

To improve workability when first and second wall bodies are installed and the first and second wall bodies are further reinforced with a third wall body installed between the first and second wall bodies in an embankment reinforcement structure.SOLUTION: An embankment reinforcement structure comprises: first and second wall bodies that are installed in an extension direction of a bank body and are parallel to each other; a third wall body that has an uneven shape in plan view and is bridged between the first and second wall bodies; and a width stop material that is joined to the third wall body and prevents recesses included in the unevenness from opening in an extension direction of the third wall body.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a bank reinforcement structure and a method for constructing the bank reinforcement structure. [Background technology]

[0002] In recent years, heavy rain disasters have become frequent, raising concerns about flooding caused by overflowing water and breaches or collapses of river levees due to scouring of the levee body. As a countermeasure against such disasters, a reinforcement structure has been proposed in which steel sheet piles are installed on both sides of the levee body, and two rows of steel sheet pile walls are constructed along the length of the levee and connected with tie members. By constructing two rows of steel sheet pile walls, the soil and sand located between the two rows of steel sheet pile walls behave as a single unit, providing high resistance to heavy rain and overflows.

[0003] Furthermore, a technology has been disclosed for improving bending moment resistance strength in existing quay walls by installing a new steel sheet pile wall that is separate from the existing steel sheet pile wall and connecting and fixing them with tie members (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-223392 Summary of the Invention [Problem to be solved by the invention]

[0005] As mentioned above, tie bars are effective components for improving the strength of walls. However, installing tie bars requires additional work, such as installing H-shaped steel beams at the top of the steel sheet pile wall and drilling holes in the steel sheet pile wall where the tie bars connect, so there is room for improvement in terms of workability.

[0006] Therefore, the present invention aims to provide an embankment reinforcement structure and a construction method for the embankment reinforcement structure that can improve construction efficiency when first and second wall bodies are installed in the embankment reinforcement structure and the first and second wall bodies are further reinforced with a third wall body installed between the first and second wall bodies. [Means for solving the problem]

[0007] [1] A levee reinforcement structure comprising first and second walls cast in the extension direction of the levee body and parallel to each other, a third wall having an uneven shape in a plan view and spanning between the first and second walls, and a width stopper joined to the third wall to prevent the recesses included in the uneven shape from opening in the extension direction of the third wall. [2] The embankment reinforcement structure described in [1], wherein the width stopper is joined to the opening of the recess. [3] The embankment reinforcement structure described in [2], wherein the width stopper is arranged across multiple recesses. [4] The embankment reinforcement structure described in [3], wherein the width stopper is arranged over the entire length of the third wall and connected to the first and second wall. [5] The embankment reinforcement structure described in [3] or [4], wherein the third wall is a steel sheet pile wall formed by connecting steel sheet piles, and the width stop material is steel. [6] The embankment reinforcement structure described in [1], wherein the width stopper is joined to the middle part of the recess. [7] The embankment reinforcement structure described in [1], wherein the third wall is a steel sheet pile wall formed by connecting steel sheet piles, and the width stop material is a steel plate joined to the opening or middle part of the recess formed by each of the steel sheet piles. [8] The embankment reinforcement structure described in [7], wherein the width stoppers are joined at a deeper position in the steel sheet piles closer to the first and second wall bodies than in the steel sheet piles farther from the first and second wall bodies. [9] The embankment reinforcement structure described in [7], wherein the width stopper is joined at a deeper position in the steel sheet pile closer to the second wall than in the steel sheet pile closer to the first wall.

[10] A levee reinforcement structure described in any one of [7] to [9], wherein the width stopper is joined to only a portion of the section on the head side of the third wall in the height direction in at least some of the steel sheet piles.

[11] The embankment reinforcement structure described in [1], wherein the width stopper is joined to the third wall at two or more points in the height direction.

[12] The embankment reinforcement structure described in [1], wherein the first and second walls are steel sheet pile walls formed by connecting steel sheet piles, and further includes an additional width stopper member that is joined to a recess formed on the opposite side of the third wall by the steel sheet piles that constitute the first or second wall at the portion where the third wall is connected.

[13] A levee reinforcement structure comprising first and second walls cast in the extension direction of the levee body and parallel to each other, a third wall having an uneven shape in a plan view and spanning between the first and second walls, and a reinforced concrete structure in which the top of the third wall is embedded and which prevents the recesses included in the uneven shape from opening in the extension direction of the third wall.

[14] [5] A construction method for a levee reinforcement structure, comprising the steps of driving the steel sheet piles into the levee body to form the third wall, and then joining the width stopper to the steel sheet pile wall.

[15] [7] A construction method for a levee reinforcement structure according to the present invention, which includes a step of joining the width stopper to the steel sheet pile, and then driving the steel sheet pile into the levee body to form the third wall. [Effects of the Invention]

[0008] According to the above configuration, a width stopper is attached to prevent the recesses included in the unevenness of the third wall body used as a tension member between the first and second wall bodies from opening in the extension direction of the third wall body. The width stopper can be installed with less incidental work on site than, for example, tie members, and therefore, the workability can be improved when reinforcing the first and second wall bodies with the third wall body. [Brief explanation of the drawings]

[0009] [Figure 1]1 is a cross-sectional view of a reinforcement structure for an embankment according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view of the embankment reinforcement structure shown in FIG. 1 with a part of the embankment body removed. [Figure 3] FIG. 3 is a plan view of the steel sheet pile wall and width stop members included in the reinforcing structure of the embankment shown in FIGS. 1 and 2. [Figure 4A] FIG. 10 is a diagram showing an example in which a width stopper is joined to the back side of the middle part of the recess of the steel sheet pile. [Figure 4B] FIG. 10 is a diagram showing an example in which a width stopper is joined to the middle part of a recess in a steel sheet pile. [Figure 4C] FIG. 10 is a diagram showing an example in which width stoppers are joined to both sides of the opening of the recess of the steel sheet pile. [Figure 5] 10A and 10B are diagrams showing modified examples of the installation depth of width stoppers in the first embodiment of the present invention. [Figure 6] 10A and 10B are diagrams showing modified examples of the installation depth of width stoppers in the first embodiment of the present invention. [Figure 7] 10A and 10B are diagrams showing modified examples of the installation depth of width stoppers in the first embodiment of the present invention. [Figure 8] 10A and 10B are diagrams showing modified examples of the installation depth of width stoppers in the first embodiment of the present invention. [Figure 9] 10A and 10B are diagrams showing modified examples of the installation depth of width stoppers in the first embodiment of the present invention. [Figure 10] 10A and 10B are diagrams showing modified examples of the installation depth of width stoppers in the first embodiment of the present invention. [Figure 11] FIG. 10 is a diagram showing an example in which width stoppers are joined to two or more locations of a steel sheet pile wall in the height direction in the first embodiment of the present invention. [Figure 12] 10A and 10B are diagrams illustrating an example of installation of additional width stoppers in the first embodiment of the present invention. [Figure 13] FIG. 10 is a plan view of a steel sheet pile wall and width stoppers included in a reinforcing structure for a levee according to a second embodiment of the present invention. [Figure 14] FIG. 10 is a cross-sectional view showing an example in which width stoppers are joined to steel sheet pile walls on both sides in a second embodiment of the present invention. [Figure 15]FIG. 10 is a diagram showing an example in which width stoppers are joined to two or more locations of a steel sheet pile wall in the height direction in the second embodiment of the present invention. [Figure 16A] FIG. 10 is a diagram showing an example of the relationship in height between the bank body and each steel sheet pile wall in an embodiment of the present invention. [Figure 16B] FIG. 10 is a diagram showing an example of the relationship in height between the bank body and each steel sheet pile wall in an embodiment of the present invention. [Figure 16C] FIG. 10 is a diagram showing an example of the relationship in height between the bank body and each steel sheet pile wall in an embodiment of the present invention. [Figure 17] FIG. 10 is a cross-sectional view of a reinforcing structure for an embankment according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0011] FIG. 1 is a cross-sectional view of a levee reinforcement structure according to a first embodiment of the present invention. FIG. 2 is a perspective view of the levee reinforcement structure shown in FIG. 1 with a portion of the levee body removed. FIG. 3 is a plan view of the steel sheet pile wall and width stop members included in the levee reinforcement structure shown in FIGS. 1 and 2. The levee body 1 constitutes, for example, a river levee or a coastal levee and is constructed along a body of water such as a river, a waterway, the sea, or a lake. In each figure, the extension direction of the levee body 1 is shown as the X direction, the width direction as the Y direction, and the height direction as the Z direction. The levee reinforcement structure includes a steel sheet pile wall 21 (first wall body) and a steel sheet pile wall 22 (second wall body) that are cast in the extension direction of the levee body 1 and are parallel to each other, and a steel sheet pile wall 23 (third wall body) that spans between the steel sheet pile walls 21 and 22 in a plan view. A steel sheet pile wall formed by connecting steel sheet piles is an example of a wall, and FIG. 3 shows a steel sheet pile 211 that constitutes the steel sheet pile wall 21, a steel sheet pile 221 that constitutes the steel sheet pile wall 22, and a steel sheet pile 231 that constitutes the steel sheet pile wall 23. The steel sheet pile walls 21, 22 and the steel sheet pile wall 23 are connected using, for example, deformed sheet piles 212, 222. The deformed sheet piles 212, 222 may be incorporated when the steel sheet pile walls 21, 22 are driven, or the deformed sheet piles 212, 222 may replace part of the regular steel sheet piles in the already driven steel sheet pile walls 21, 22. In the latter case, for example, a regular steel sheet pile is cut at the head, and the cut part is replaced with the deformed sheet piles 212, 222. Alternatively, without using deformed sheet piles, the steel sheet pile wall 23 may be connected to the steel sheet pile walls 21, 22 by welding steel materials such as shaped steel materials, steel plates, or reinforcing bars between the already installed steel sheet pile walls 21, 22 and the steel sheet pile wall 23. Note that the steel sheet pile walls 21, 22 do not necessarily have to be steel sheet pile walls, and in other embodiments, they may be concrete walls, for example.

[0012] By constructing walls such as steel sheet pile walls 21 and 22 on the embankment body 1, it is possible to increase resistance to forces acting, for example, when the water level rises. Furthermore, even if the slope of the embankment body 1 is washed away by rising water levels, the area between the steel sheet pile walls 21 and 22 remains, allowing the embankment to maintain its function. However, because the steel sheet pile walls have an uneven shape in plan view as shown in Figure 3, it is necessary to prevent deformation of the steel sheet pile wall 23 due to deformation that opens up the recesses when a tensile force acts on the steel sheet pile walls 21 and 22 in the width direction of the embankment body 1.

[0013] Therefore, in this embodiment, width stoppers 3A are joined to the steel sheet pile wall 23 in a plan view to prevent the recess from opening in the extension direction of the steel sheet pile wall 23 (the Y direction in the figure). As shown in Figures 4A to 4C, the width stoppers 3A are steel plates joined to the opening or middle part of the recess formed by each steel sheet pile 231 that constitutes the steel sheet pile wall 23. In the example of Figure 4A, the steel sheet pile 231 is a hat-shaped steel sheet pile, and the width stoppers 3A are joined to both flanges at the back side of the middle part of the recess formed by the web and flange of the steel sheet pile 231. In the example of Figure 4B, the width stoppers 3A are joined to both flanges at the middle position between the web and arm at the middle part of the recess. In the example of Figure 4C, the width stoppers 3A are joined to both arms or to the connection part between the flange and arm at the opening of the recess. From a mechanical viewpoint, the example of Figure 4B is preferable to the example of Figure 4A, and the example of Figure 4C is preferable to the example of Figure 4B. More specifically, assuming that the depth of the recess (i.e., the distance from the web to the arm in the direction perpendicular to the extension direction of the steel sheet pile wall 23) is h, the width stoppers 3A are preferably attached within a range of 1 / 2h from the opening of the recess, and more preferably within a range of 1 / 3h from the opening. On the other hand, from the viewpoint of the amount of steel material to be used, the examples shown in Figs. 4A and 4B may also be useful. By arranging such width stoppers 3A, even if a large tensile force acts on the steel sheet pile wall 23 due to a force exerted on either or both of the steel sheet pile walls 21 and 22 toward the outside of the width direction of the embankment body 1, the width stoppers 3A bear the tensile force, thereby suppressing deformation of the steel sheet pile wall 23 such that the recess opens. Note that while the above description has been given for the case where the steel sheet pile 231 is a hat-shaped steel sheet pile, a similar configuration is also possible for U-shaped steel sheet piles or Z-shaped steel sheet piles, in which separate steel sheet piles are used on both sides of the recess, as will be described later.

[0014] The steel sheet piles 231 and the width stoppers 3A that constitute the steel sheet pile wall 23 are joined by, for example, welding. For example, bolting is also possible when the width stoppers 3A are installed by overlapping the arms on both sides of the opening. For example, if the steel sheet piles 231 are hat-shaped steel sheet piles as shown in the example, the width stoppers 3A can be joined to the steel sheet piles 231 in advance at a factory or the like, and then the steel sheet piles 231 can be delivered to the site and driven into the embankment 1 to form the steel sheet pile wall 23. Note that in the example shown, the width stoppers 3A are not placed at the upper end of the head of the steel sheet pile 231, which is held by a construction machine. However, the width stoppers 3A may be placed up to the upper end of the steel sheet pile 231, for example, if there is no interference with the construction machine. If the width stoppers 3A joined to the steel sheet piles 231 in advance at a factory or the like can suppress deformation of the steel sheet pile wall 23 and be used as tension members between the steel sheet pile walls 21 and 22, construction can be simplified by, for example, eliminating or reducing the need for on-site tie members and wale bracing. For example, when reinforcing an existing embankment, if tie bars are to be installed in two layers, one near the top and one in the middle of the wall, the embankment must be excavated after the wall is poured to install the tie bars. This increases construction time and costs due to the need to dispose of the excavated soil and prevent the wall from collapsing during excavation. In contrast, if the wall can be constructed by joining width stoppers 3A to the steel sheet piles 231 in advance and then pouring them, as in the above-mentioned embodiment, it becomes possible to reinforce the middle and bottom of the wall without excavating the embankment. Furthermore, if tie bars and wales can be omitted, there is no need to procure tie bars or H-shaped steel materials separately from the steel sheet piles. This makes it relatively easy to respond even when material procurement becomes difficult, for example, during emergency restoration.

[0015] Alternatively, the width stop members 3A may be joined after the steel sheet piles 231 are driven into the embankment body 1 to form the steel sheet pile wall 23. In this case, it is also possible to deal with the case where the steel sheet piles that form the steel sheet pile wall 23 are U-shaped steel sheet piles or Z-shaped steel sheet piles, and separate steel sheet piles are provided on both sides of the recess to which the width stop members are joined. Even when the width stop members 3A are joined after the steel sheet pile wall 23 is driven, the width stop members 3A of this embodiment are easy to handle because they are steel plates attached to individual steel sheet piles 231, compared to tie members that require a length equivalent to the full width between the steel sheet pile walls 21, 22.

[0016] 5 to 10 are diagrams showing modified examples of the installation depth of the width stoppers in the first embodiment of the present invention. In the example shown in Fig. 1 above, the width stoppers 3A were joined to almost the entire section of the steel sheet pile wall 23 in the height direction, but in the example described below, the width stoppers 3A are joined to only a part of the section of the steel sheet pile wall 23 in the height direction.

[0017] In the example of FIG. 5, the upper end height H of the steel sheet pile walls 21 and 22 L In the embankment body 1, width stoppers 3A are joined to the steel sheet pile walls 23 within a range of 0.5 m from the top ends of the steel sheet pile walls 21, 22. More specifically, the center positions of the width stoppers 3A in the depth direction are within a range of 0.5 m from the top ends of the steel sheet pile walls 21, 22. Since tie members are generally installed within a range of 0.5 m from the top end of the wall body, similar effects can be obtained by arranging the width stoppers 3A in the same way as tie members, which are installed as replacements or reinforcements for tie members.

[0018] In the example in Figure 6, 1 / 2H from the top surface L The width stopper 3A is joined to the steel sheet pile wall 23 within the range. The tensile force between the steel sheet pile walls 21 and 22 is approximately 1 / 2H deep from the top surface. L Therefore, by arranging the width stopper 3A in this range, the steel sheet pile wall 23 can function effectively as a tensile member.

[0019] In the example of Figure 7, the depth H from the top surface L The width stoppers 3A are joined to the steel sheet pile wall 23 in the range up to the height of the embankment, i.e., in a range roughly equal to the height of the embankment. By joining the width stoppers 3A to the steel sheet pile wall 23 throughout the embankment body 1, they not only function as tensile members but also improve the rigidity of the entire embankment reinforcement structure.

[0020] In the examples shown in Figures 8 and 9, the width stoppers are joined to the steel sheet pile wall 23 at different depths depending on the position in the width direction of the embankment body 1. In the example shown in Figure 8, the width stopper 3B joined to the steel sheet pile close to the steel sheet pile walls 21, 22 is joined at a deeper position than the width stopper 3C joined to the steel sheet pile far from the steel sheet pile walls 21, 22. In the illustrated example, the width stopper 3B is joined to a depth H LThe width stopper 3C is joined in the range from the top surface to 0.5m, but it is not limited to this example, for example, the depth from the top surface mentioned above is 1 / 2H L The width stoppers 3B may be joined to a depth ranging from 0 to 1000 m. The depth to which the width stoppers are joined may vary in more than two stages. By joining the width stoppers 3B to a deeper position for the steel sheet piles of the steel sheet pile wall 23 that are close to the steel sheet pile walls 21 and 22 and are likely to be subjected to a greater tensile force, the steel sheet pile wall 23 can be effectively reinforced against tensile force while suppressing an increase in the amount of steel material used due to the width stoppers.

[0021] On the other hand, in the example shown in Figure 9, the width stopper 3E connected to the steel sheet pile wall 22 of the steel sheet pile wall 23 is connected at a deeper position than the width stopper 3A connected to the steel sheet pile wall 21. As described above, the embankment 1 is constructed along a water body. For example, if the steel sheet pile wall 21 is on the water body side, overflowing will cause erosion and scouring of the slope and ground on the opposite side of the water body, which exerts passive resistance against the steel sheet pile wall 22, causing the steel sheet pile wall 22 to deform toward the opposite side of the water body. To prevent this deformation, the tensile force applied to the steel sheet pile wall 23 increases. Therefore, the width stopper 3E is connected to a longer section of the steel sheet pile near the steel sheet pile wall 22 on the opposite side of the water body. By connecting the width stopper deeper only to the section of the steel sheet pile wall 23 where the tensile force is high, the steel sheet pile wall 23 can be reinforced in terms of tensile force without increasing the amount of steel used due to the width stopper.

[0022] In the example shown in Figure 10, the depth arrangement is the same as in Figure 9, but the height of the stoppers themselves is minimized. That is, the stoppers 3G attached to the steel sheet piles closer to the steel sheet pile wall 22 of the steel sheet pile wall 23 are attached deeper than the stoppers 3F attached to the steel sheet piles closer to the steel sheet pile wall 21, but the height dimensions of the stoppers 3F and 3G are similar. Therefore, on the steel sheet pile wall 22 side, there is a large gap between the head of the steel sheet pile and the stoppers 3G. As explained in the example of Figure 9 above, if the steel sheet pile wall 21 faces the water body, overflowing will cause erosion and scouring of the slope and ground on the opposite side of the water body, which exert passive resistance against the steel sheet pile wall 22, and the steel sheet pile wall 22 will tend to deform toward the opposite side of the water body. To prevent this deformation, the tensile force applied to the steel sheet pile wall 23 will increase. This configuration allows the steel sheet pile wall 23 to be reinforced against tensile forces without increasing the amount of steel used due to the stoppers.

[0023] 11 is a diagram showing an example in which width stoppers are joined to two or more points of the steel sheet pile wall in the height direction in the first embodiment of the present invention. More specifically, width stoppers 3A are joined in the range from the top surface to 0.5 m, and width stoppers 3H are joined to a depth H from the top surface. L As explained with reference to Figure 5, the upper stopper 3A functions similarly to a tie member. On the other hand, the lower stopper 3H functions as a tension member in the event that the slope of the embankment body 1 is washed away due to rising water levels or other reasons.

[0024] FIG. 12 is a diagram illustrating an example of installing additional width stoppers in the first embodiment of the present invention. As described above, the steel sheet pile walls 21, 22 and the steel sheet pile wall 23 are connected using, for example, deformed sheet piles 212, 222. The deformed sheet piles 212, 222 are steel sheet piles that constitute the steel sheet pile walls 21, 22 at the portion where the steel sheet pile wall 23 is connected. As shown in the figure, if the deformed sheet piles 212, 222 have recesses on the side opposite the steel sheet pile wall 23, a force that deforms the steel sheet pile wall 23 in a direction that closes the recesses acts when a tensile force acts on the steel sheet pile wall 23, and a force that deforms the steel sheet pile wall 23 in a direction that opens the recesses acts when a compressive force acts on the steel sheet pile wall 23. Therefore, additional width stoppers 4 may be joined to the recesses of the deformed sheet piles 212, 222 to prevent deformation not only of the steel sheet pile wall 23 but also of the steel sheet pile walls 21, 22.

[0025] FIG. 13 is a plan view of a steel sheet pile wall and width stoppers included in a reinforcing structure for a levee according to a second embodiment of the present invention. In this embodiment, width stoppers 5A are arranged across multiple recesses, instead of the width stoppers arranged in each recess formed by the steel sheet pile wall 23 as in the first embodiment. Various steel materials, such as shaped steel materials such as H-shaped steel, channel steel, angle steel, or flat steel, steel plates, or reinforcing bars, are used for the width stoppers 5A. The width stoppers 5A and the individual steel sheet piles 231 constituting the steel sheet pile wall 23 are joined by, for example, bolts. In this embodiment, the width stoppers 5A are joined to the recesses formed by the steel sheet pile wall 23, so that deformation of the recesses is suppressed even when a large tensile force acts on the steel sheet pile wall 23.

[0026] In this embodiment, the width stoppers 5A are joined after the steel sheet pile wall 23 is constructed by driving the steel sheet piles 231 into the embankment body 1. As in the example shown in Fig. 14 , the width stoppers 5A may be arranged over the entire length of the steel sheet pile wall 23 and connected to the steel sheet pile walls 21, 22. In this case, the width stoppers 5A are similar to tie members in that they are connected to the steel sheet pile walls 21, 22, but differ from tie members in that they are joined not only to the steel sheet pile walls 21, 22 but also to both sides of the recess of the steel sheet pile wall 23 along the way.

[0027] 15 is a diagram showing an example in which width stoppers are joined to two or more locations in the height direction of a steel sheet pile wall in the second embodiment of the present invention. In the example shown, width stopper 5A is joined near the upper end of the steel sheet pile wall 23, and width stopper 5B is joined below that. By arranging width stoppers 5A and 5B in double as in this example, it is possible to provide the steel sheet pile wall 23 with sufficient performance as a tensile member, even if each width stopper 5A and 5B is a member with a relatively small cross section that is easy to handle.

[0028] 16A to 16C are diagrams showing examples of the height relationship between the embankment wall and each steel sheet pile wall in an embodiment of the present invention. In the example of FIG. 16A, the steel sheet pile walls 21 and 22 are aligned with the top surface of the embankment wall 1, while the steel sheet pile wall 23 protrudes from the top surface, and a width stopper 5A joined near the upper end of the steel sheet pile wall 23 also protrudes from the top surface. In the example of FIG. 16B, the steel sheet pile walls 21 and 22 and the steel sheet pile wall 23 all protrude from the top surface of the embankment wall 1. In the example of FIG. 16C, the steel sheet pile walls 21 and 22 protrude from the top surface of the embankment wall 1, while the steel sheet pile wall 23 is aligned with the top surface. While the figures show an example of the second embodiment including the width stopper 5A, the same applies to the first embodiment. Furthermore, the height relationship between the lower ends of the steel sheet pile walls 21, 22 and the steel sheet pile wall 23 is not particularly limited; for example, the lower end of the steel sheet pile wall 23 may be located in the middle of the steel sheet pile walls 21, 22 as in the example shown, or it may be located near the lower ends of the steel sheet pile walls 21, 22.

[0029] 17 is a cross-sectional view of a reinforcing structure for a levee according to a third embodiment of the present invention. In this embodiment, instead of using width stoppers joined to recesses formed by the steel sheet pile wall 23 as in the above-described embodiment, a reinforced concrete structure 6 is arranged in which the head of the steel sheet pile wall 23 is embedded in a section including the recesses of the steel sheet pile wall. In this case, as in the case where width stoppers are joined, deformation that opens up the recesses is suppressed even when a large tensile force acts on the steel sheet pile wall 23. [Explanation of symbols]

[0030] 1... embankment body, 21, 22, 23... steel sheet pile wall, 211, 221, 231... steel sheet pile, 212... deformed sheet pile, 222... deformed sheet pile, 3A, 3B, 3C, 3E, 3F, 3G, 3H... width stopper, 4... additional width stopper, 5A, 5B... width stopper, 6... reinforced concrete structure.

Claims

1. first and second walls cast in the extension direction of the bank body and arranged parallel to each other; a third wall body having an uneven shape in a plan view and spanning between the first and second walls; a width stopper member that is joined to the third wall body and that prevents recesses included in the irregularities from opening in the extension direction of the third wall body; A levee reinforcement structure equipped with:

2. The embankment reinforcement structure according to claim 1 , wherein the width stopper is joined to an opening of the recess.

3. The embankment reinforcement structure according to claim 2 , wherein the width stopper is arranged across a plurality of the recesses.

4. The embankment reinforcement structure according to claim 3 , wherein the width stopper is disposed over the entire length of the third wall body and connected to the first and second wall bodies.

5. the third wall body is a steel sheet pile wall formed by connecting steel sheet piles, 5. The embankment reinforcement structure according to claim 3, wherein the width stopper is a steel material.

6. The embankment reinforcement structure according to claim 1 , wherein the width stopper is joined to a middle portion of the recess.

7. the third wall body is a steel sheet pile wall formed by connecting steel sheet piles, The embankment reinforcement structure according to claim 1 , wherein the width stoppers are steel plates joined to openings or intermediate portions of the recesses formed by the individual steel sheet piles.

8. The embankment reinforcement structure according to claim 7, wherein the width stoppers are joined at a deeper position in the steel sheet piles closer to the first and second wall bodies than in the steel sheet piles farther from the first and second wall bodies.

9. The embankment reinforcement structure according to claim 7 , wherein the width stoppers are joined at deeper positions in the steel sheet piles closer to the second wall body than in the steel sheet piles closer to the first wall body.

10. The embankment reinforcement structure according to any one of claims 7 to 9, wherein the width stopper is joined to only a portion of the section on the head side of the third wall body in the height direction in at least some of the steel sheet piles.

11. The embankment reinforcement structure according to claim 1 , wherein the width stopper is joined to the third wall body at two or more points in the height direction.

12. the first and second wall bodies are steel sheet pile walls formed by connecting steel sheet piles, 2. The embankment reinforcement structure according to claim 1, further comprising an additional width stopper member joined to a recess formed on the opposite side of the third wall body by a steel sheet pile constituting the first or second wall body at the portion where the third wall body is connected.

13. first and second walls cast in the extension direction of the bank body and arranged parallel to each other; a third wall body having an uneven shape in a plan view and spanning between the first and second walls; a reinforced concrete structure in which the head of the third wall body is embedded and which prevents a recess included in the unevenness from opening in the extension direction of the third wall body; A levee reinforcement structure equipped with:

14. A construction method for the embankment reinforcement structure according to claim 5, A construction method for a bank reinforcement structure, comprising a step of driving the steel sheet piles into the bank body to form the third wall, and then joining the width stopper material to the steel sheet pile wall.

15. A construction method for the embankment reinforcement structure according to claim 7, a step of joining the width stopper to the steel sheet pile, and then driving the steel sheet pile into the embankment body to form the third wall;

Images