Seawall structure and repair method for seawall structure

Abstract

The embankment will provide a revetment structure that can appropriately respond to the settlement of structures on the existing rubble-stone sloping embankment. [Solution] The revetment structure comprises an existing rubble sloping embankment that slopes from the existing revetment toward an impermeable improved foundation on the seaward side, a revetment structure placed on the impermeable improved foundation, and a caisson structure that is connected to the revetment structure on the existing rubble sloping embankment and extends in a first direction toward the existing revetment. The caisson structure is arranged so as to lay a waterproof sheet laid on the existing rubble sloping embankment, and has walls at both ends in a second direction perpendicular to the first direction and along the horizontal plane, and a filling material that fills the space between the walls of the caissons, and multiple caissons are provided so as to be connectable in the vertical direction.

Description

Technical Field

[0001] The present invention relates to a revetment structure and a method for repairing the revetment structure.

Background Art

[0002] There has been an attempt to lay a water shielding sheet on the surface of an existing riprap inclined embankment revetment to form a water shielding sheet type surface water protection work, which is used as a normal line of a managed revetment. As a typical stable revetment structure, many of the aforementioned existing riprap inclined embankment revetments that have been conventionally used are constructed on a water permeability improvement foundation (sand mat method, sand drain method, sand compaction method, etc.) with a low settlement suppression effect. On the other hand, since the ground improvement work of a managed revetment requires impermeability improvement, it is constructed on an impermeability improvement foundation (block type deep mixing improvement method, etc.) that is rich in impermeability and has a rich settlement suppression effect.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to construct a controlled waste disposal site that forms a standard of controlled revetment by laying a waterproof sheet on the surface of the existing rubble sloping revetment described above to create a waterproof sheet surface waterproofing structure, a controlled revetment structure with a concave cross-section must be placed on the seaward side of the rubble sloping revetment equipped with the waterproof sheet surface waterproofing structure, and this structure must be joined to the rubble sloping revetment equipped with the waterproof sheet surface waterproofing structure to ensure continuity of waterproofing. The existing rubble sloping revetment described above has a lower settlement suppression effect than the already implemented ground improvement work. On the other hand, the newly constructed controlled revetment with a concave cross-section will be equipped with an impermeable improved base that is highly impermeable and highly effective in suppressing settlement. Therefore, if the upper structure settles together with the existing rubble sloping revetment, it may become impossible to guarantee the continuity of waterproofing, which is an essential condition for controlled revetments.

[0005] This invention has been made in view of the above, and aims to provide a revetment structure and a method for repairing a revetment structure that can appropriately ensure the continuity of watertightness even when an existing rubble-stone sloping revetment subsides. [Means for solving the problem]

[0006] The revetment structure according to the present invention comprises an existing rubble sloping embankment that slopes from the existing revetment toward an impermeable improved foundation on the seaward side, a revetment structure disposed on the impermeable improved foundation, and a caisson structure that is disposed on the existing rubble sloping embankment connected to the revetment structure and extends in a first direction toward the existing revetment, wherein the caisson structure is disposed so as to lay a waterproof sheet laid on the existing rubble sloping embankment and has walls at both ends in a second direction perpendicular to the first direction and along the horizontal plane, and a filling material that is filled between the walls of the caisson, and a plurality of the caissons are provided so as to be connectable in the vertical direction.

[0007] The present invention relates to a method for repairing a revetment structure, comprising: connecting a new caisson to the upper part of an existing caisson; and filling the space between the wall portions of the new caisson with the space above the filling between the wall portions of the existing caisson. [Effects of the Invention]

[0008] According to the present invention, a revetment structure and a method for repairing a revetment structure can be provided that can appropriately ensure the continuity of watertightness even when an existing rubble-stone sloping revetment has subsided. [Brief explanation of the drawing]

[0009] [Figure 1] Figure 1 is a plan view showing an example of a revetment structure according to the present disclosure. [Figure 2] Figure 2 is a cross-sectional view showing an example of a revetment structure according to the present disclosure. [Figure 3] Figure 3 is a cross-sectional view showing an example of a revetment structure according to the present disclosure. [Figure 4A] Figure 4A shows an example of a repair method for the upper part of the revetment structure shown in Figure 3. [Figure 4B] Figure 4B shows an example of a configuration in which multiple caissons are connected vertically. [Figure 5] Figure 5 shows an example of a configuration in which multiple caissons are connected vertically. [Figure 6] Figure 6 is a schematic diagram showing an enlarged view of the connection between the caisson on the revetment structure side and the caisson on the existing structure side. [Figure 7] Figure 7 is a schematic plan view showing another example of a vertical joint. [Figure 8] Figure 8 is a schematic plan view showing another example of a vertical joint. [Figure 9] Figure 9 is a schematic plan view showing another example of a vertical joint. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments of the revetment structure according to the present invention will be described with reference to the drawings. However, the present invention is not limited by these embodiments. Furthermore, the components in the following embodiments include those that are easily substituted or substantially identical to those that are easily substituted by those skilled in the art.

[0011] Figures 1 to 3 show an example of a revetment structure 100 according to the embodiment of this disclosure. Figure 1 is a plan view. Figure 2 shows the configuration along section AA in Figure 1. Figure 3 shows the configuration along section BB in Figure 1.

[0012] In this embodiment, the revetment structure 100 shown in Figures 1 to 3 is a controlled revetment that constitutes, for example, a marine disposal site for waste. As shown in Figures 1 to 3, the revetment structure 100 is constructed on the sea area S side relative to a predetermined existing revetment 50. The revetment structure 100 comprises an existing rubble sloping embankment 10, a revetment structure 20, and a caisson structure 30.

[0013] The existing rubble sloping embankment 10 slopes from the existing revetment 50 to the impermeable improved base 40 on the seaward side. The existing rubble sloping embankment 10 has a rubble layer 11, a protective layer 12, and a waterproof sheet 13. The rubble layer 11 is made up of multiple rubble stacked on top of each other. The protective layer 12 is placed on the upper surface of the rubble layer 11. The protective layer 12 protects the waterproof sheet 13. The waterproof sheet 13 is placed on the upper surface of the protective layer 12. The waterproof sheet 13 prevents retained water from entering the protective layer 12 and the rubble layer 11. As shown in Figure 3, the waterproof sheet 13 is positioned so that one end in the second direction D2 (the disposal site side) extends from the caisson 31 towards the disposal site. The waterproof sheet 13 may have its other end in the second direction D2 (seaside: next-generation disposal site side) extend, for example, to the seaside of the caisson 31, and may be joined and integrated with the waterproof sheet of the next-generation disposal site during its construction. Alternatively, the waterproof sheet 13 may be arranged over a range from the disposal site side in the second direction to any position at the bottom of the caisson 31, and not be arranged on the seaside from that position.

[0014] The revetment structure 20 is placed on an impermeable improved foundation 40. Examples of revetment structures 20 include various structures such as caissons, cells, and L-shaped blocks. Section 1 (see Figure 2) where the revetment structure 20 is placed is a section where settlement is suppressed by an impermeable improved foundation such as CDM.

[0015] The caisson structure 30 is arranged on the existing riprap slope 10. More specifically, the caisson structure 30 is arranged on the water barrier sheet 13 of the existing riprap slope 10 so as to lay the water barrier sheet 13. The caisson structure 30 is arranged in connection with the revetment structure 20. The caisson structure 30 extends in the first direction D1 towards the existing revetment 50. The section 2 (see FIG. 2) where the caisson structure 30 is arranged is a section where settlement occurs because no active ground improvement has been carried out.

[0016] The caisson structure 30 has a caisson 31 and a filling material 32. The caisson 31 has wall portions 33 at both ends in the second direction D2 that is orthogonal to the first direction D1 and along the horizontal plane. The wall portions 33 may be arranged in a separated state in the second direction D2, or may be connected by a gable wall (not shown) or the like at both ends in the first direction D1. In the caisson 31, the gable wall may or may not be provided. The filling material 32 is arranged between the wall portions 33 of the caisson 31. The filling material 32 includes one or more impermeable water barrier materials among asphalt-based water barrier materials, soil-based water barrier materials, cement-based water barrier materials, and chemical-based water barrier materials. The filling material 32 may include riprap. In the present embodiment, the filling material 32 is, for example, only an asphalt mixture or a combination of riprap and an asphalt mixture. The bottom of the filling material 32 is connected to the water barrier sheet 13. With this configuration, a continuity of vertical and horizontal water barrier is formed at the interface between the filling material 32 and the water barrier sheet 13.

[0017] The caisson structure 30 is provided with a plurality of caissons 31 that can be connected vertically. For example, when the caisson structure 30 on the existing rubble mound breakwater 10 sinks, repairs can be carried out by connecting a new caisson 31 to the upper part of the existing caisson 31 and arranging it, so that the height of the caisson structure 30 above the sea surface can be appropriately ensured. Fig. 4A is a diagram showing an example of the repair method of the revetment structure 100. As shown in Fig. 4A, in the repair method of the revetment structure 100, first, a new caisson 31 is connected to the upper part of the existing caisson 31 (ST1). Next, a new filler 32 is filled between the wall portions 33 of the new caisson 31 and above the filler 32 between the wall portions 33 of the existing caisson 31 (ST2).

[0018] Fig. 4B is a diagram showing an example of a state where a plurality of caissons 31 are connected vertically. Fig. 4B shows a configuration in which two caissons 31 are connected vertically. Hereinafter, when distinguishing between two caissons 31, the lower caisson 31 is denoted as the lower caisson 31A, and the upper caisson 31 is denoted as the upper caisson 31B. Also, the filler 32 of the lower caisson 31A is denoted as the filler 32A, and the wall portion 33 of the lower caisson 31A is denoted as the wall portion 33A. Similarly, the filler 32 of the upper caisson 31B is denoted as the filler 32B, and the wall portion 33 of the upper caisson 31B is denoted as the wall portion 33B.

[0019] As shown in Fig. 4B, the caisson structure 30 has vertical joint portions 34 by which the upper caisson 31B is connected to the lower caisson 31A. The vertical joint portions 34 are arranged at the bottoms of the respective wall portions 33B of the upper caisson 31B. Each vertical joint portion 34 has a shape bent outward in the second direction D2 with respect to the wall portion 33A of the lower caisson 31A.

[0020] When the upper caisson 31B is arranged on the upper surface of the lower caisson 31A, the above-mentioned vertical joint portions 34 are locked to the wall portion 33A of the lower caisson 31A. In this way, with the vertical joint portions 34 locked to the wall portion 33 of the lower caisson 31A, the upper caisson 31B is connected to the lower caisson 31A.

[0021] In the caisson structure 30, the lowest caisson 31 is positioned with its lower surface 31a (see Figure 2) inclined relative to the horizontal plane so as to follow the existing rubble levee 10. This makes it easy to position the caisson 31 along the slope of the existing rubble levee 10. Furthermore, the upper surface 31b (see Figure 2) of the caisson 31 is shaped to follow the horizontal plane. This allows for stabilization of the upper caisson 31 when connecting another caisson 31 to the upper surface 31b of the caisson 31.

[0022] The caisson structure 30 is arranged with multiple caissons 31 connected to each other along a first direction D1. Figure 5 shows an example of multiple caissons 31 connected in the first direction D1. Hereinafter, when distinguishing between two caissons 31 in the first direction D1, the caisson 31 on the side of the revetment structure 20 will be referred to as the revetment structure side caisson 31C, and the caisson 31 on the side of the existing revetment 50 will be referred to as the existing structure side caisson 31D. Also, the filling 32 of the revetment structure side caisson 31C will be referred to as filling 32C, and the wall portion 33 of the revetment structure side caisson 31C will be referred to as wall portion 33C. Similarly, the filling 32 of the existing structure side caisson 31D will be referred to as filling 32D, and the wall portion 33 of the existing structure side caisson 31D will be referred to as wall portion 33D.

[0023] As shown in Figure 5, the caisson structure 30 has a vertical joint 35 connecting the existing structure side caisson 31D to the revetment structure side caisson 31C. Here, we will explain using a configuration in which the vertical joint 35 is located on the existing structure side caisson 31D as an example, but the explanation is not limited to this configuration. The vertical joint 35 may also be located on the revetment structure side caisson 31C.

[0024] The vertical joints 35 are provided on each wall portion 33D of the existing structure side caisson 31D. The vertical joints 35 have a shape that is bent outward in the second direction D2 relative to the wall portion 33C of the revetment structure side caisson 31C. The vertical joints 35 are locked to the wall portion 33C of the revetment structure side caisson 31C. By locking the vertical joints 35 to the wall portion 33C of the revetment structure side caisson 31C, the existing structure side caisson 31D is positioned connected to the revetment structure side caisson 31C.

[0025] Figure 6 is a schematic diagram showing an enlarged view of the connection between the revetment structure side caisson 31C and the existing structure side caisson 31D. As shown in Figure 6, at the connection between the revetment structure side caisson 31C and the existing structure side caisson 31D, the wall sections 33C are connected by a gable wall 39C at the end in the first direction D1. Alternatively, the gable wall 39C may not be provided, and the filling material 32C and filling material 32D may be directly joined. Furthermore, the vertical joint 35 is positioned between the wall section 33C of the revetment structure side caisson 31C with a gap C in both the first direction D1 and the second direction. This gap C is set to allow for positional displacement in the first direction D1 and the second direction D2 when one or both of the revetment structure side caisson 31C and the existing structure side caisson 31D settle.

[0026] Thus, at the connection point between the revetment structure side caisson 31C and the existing structure side caisson 31D, a gap C is provided between the vertical joint 35 and the wall portion 33C of the revetment structure side caisson 31C. Therefore, by setting the particle size of the filler material 32 so that it does not escape from the gap C, a vertical impermeable wall can be formed.

[0027] Furthermore, the vertical joint 35 is not limited to a shape that is bent outward in the second direction D2 relative to the wall portion 33 of the caisson 31C on the revetment structure side. Figures 7 to 9 are schematic plan views showing other examples of vertical joints.

[0028] As shown in Figure 7, each vertical joint 36 may have a shape that branches off from both sides in the second direction D2, sandwiching the wall portion 33C of the caisson 31C on the revetment structure side. In this configuration, gaps C1 are formed between the vertical joint 36 and the wall portion 33C in the first direction D1 and the second direction D2, respectively.

[0029] Furthermore, as shown in Figure 8, each vertical joint 37 may have a shape that is bent inward in the second direction D2 relative to the wall portion 33C of the caisson 31C on the revetment structure side. In this configuration, gaps C2 are formed between the vertical joint 37 and the wall portion 33C in the first direction D1 and the second direction D2, respectively.

[0030] Furthermore, as shown in Figure 9, one vertical joint 38 of the existing structure side caisson 31D may be bent outward in the second direction D2 relative to the wall portion 33C of the revetment structure side caisson 31C, and the other vertical joint 38 may be bent inward in the second direction D2 relative to the wall portion 33C of the revetment structure side caisson 31C. In this configuration, gaps C3 are formed between the vertical joint 38 and the wall portion 33C in the first direction D1 and the second direction D2, respectively.

[0031] As described above, the revetment structure 100 according to this embodiment comprises an existing rubble sloping embankment 10 that slopes from the existing revetment 50 to the impermeable improved base 40 on the seaward side, a revetment structure 20 arranged on the impermeable improved base 40, and a caisson structure 30 that is arranged on the existing rubble sloping embankment 10 in connection with the revetment structure 20 and extends in a first direction D1 toward the existing revetment 50. The caisson structure 30 is arranged so as to lay the impermeable sheet 13 laid on the existing rubble sloping embankment 10, and has walls 33 at both ends in a second direction D2 perpendicular to the first direction D1 and along the horizontal plane, and has a filling material 32 that is filled between the walls 33 of the caisson 31, and multiple caissons 31 are provided so as to be connectable in the vertical direction.

[0032] With this configuration, if the caisson structure 30 on the existing rubble sloping seawall 10 sinks, a new caisson 31 can be connected to the top of the existing caisson 31, thereby ensuring that the height of the caisson structure 30 above sea level is appropriately maintained. This makes it possible to appropriately ensure the continuity of waterproofing even if the existing rubble sloping seawall 10 sinks.

[0033] In the revetment structure 100 according to this embodiment, the caisson structure 30 is provided in which a plurality of caissons 31 are connected in the vertical direction.

[0034] With this configuration, since multiple caissons 31 are provided in the caisson structure 30 in a state where they are connected in the vertical direction, the height of the caisson structure 30 above sea level can be appropriately secured.

[0035] In the revetment structure 100 according to this embodiment, the caisson 31 located at the lowest end of the caisson structure 30 has a shape in which its lower surface 31a is inclined along the existing rubble sloping embankment 10.

[0036] With this configuration, in the caisson structure 30, the lower surface 31a of the caisson 31, which is positioned at the very bottom, is inclined along the existing rubble sloping embankment 10, so that the caisson 31 can be easily positioned along the slope of the existing rubble sloping embankment 10.

[0037] In the revetment structure 100 according to this embodiment, the existing rubble sloping embankment 10 has a rubble layer 11 in which a plurality of rubble stones are stacked, a protective layer 12 placed on the upper surface of the rubble layer 11, and a waterproof sheet 13 placed on the upper surface of the protective layer 12, and the caisson structure 30 is placed on the waterproof sheet 13, and the bottom of the filling material 32 is connected to the waterproof sheet 13.

[0038] With this configuration, the caisson structure 30 is placed on the impermeable sheet 13 of the existing rubble levee 10, and the bottom of the filling material 32 is connected to the impermeable sheet 13, so that an impermeable barrier can be formed between the filling material 32 of the caisson structure 30 and the impermeable sheet 13.

[0039] In the revetment structure 100 according to this embodiment, the caisson structure 30 is arranged such that a plurality of caissons 31 are connected to each other along the first direction D1.

[0040] With this configuration, the caisson structure 30 is made up of multiple caissons 31 connected to each other along the first direction D1, so the caisson structure 30 can be easily placed on the existing rubble sloping embankment 10.

[0041] In the revetment structure 100 according to this embodiment, the caisson structure 30 has a vertical joint 35 that connects a caisson 31 (existing structure side caisson 31D) located on one side of the first direction D1 to a caisson 31 (revetment structure side caisson 31C) located on the other side of the first direction D1.

[0042] With this configuration, the vertical joint 35 can reliably connect one caisson 31 in the first direction D1 to the other caisson 31.

[0043] In the revetment structure 100 according to this embodiment, the vertical joint 35 is positioned with a gap C in the first direction D1 and the second direction D2 relative to the other caisson 31 (revetment structure side caisson 31D).

[0044] With this configuration, a gap C is provided between the vertical joint 35 and the other caisson 31, so that when each caisson 31 settles, interference with other caissons 31 can be suppressed.

[0045] In the revetment structure 100 according to this embodiment, the filling material 32 includes one or more impermeable waterproofing materials selected from asphalt-based waterproofing materials, soil-based waterproofing materials, cement-based waterproofing materials, and chemical-based waterproofing materials.

[0046] With this configuration, the filling material 32 includes one or more impermeable waterproofing materials selected from asphalt-based waterproofing materials, soil-based waterproofing materials, cement-based waterproofing materials, and chemical-based waterproofing materials, thereby ensuring proper waterproofing.

[0047] In the revetment structure 100 according to this embodiment, the filling material 32 includes rubble.

[0048] With this configuration, by including rubble in the filling material 32, the amount of impermeable waterproofing material used can be reduced.

[0049] The method for repairing the revetment structure 100 according to this embodiment is a method for repairing the above-mentioned revetment structure 100, wherein a new caisson 31 is connected to the upper part of an existing caisson 31, and new filler material 32 is filled between the wall portions 33 of the new caisson 31 and on top of the filler material 32 between the wall portions 33 of the existing caisson 31.

[0050] With this configuration, if the caisson structure 30 on the existing rubble sloping seawall 10 sinks, a new caisson 31 is connected to the top of the existing caisson 31 and new filling material 32 is filled between the wall portions 33 of the new caisson 31 and on top of the filling material 32 of the caisson structure 30, thereby ensuring that the height of the caisson structure 30 above sea level is appropriately maintained. This makes it possible to appropriately ensure the continuity of waterproofing even if the existing rubble sloping seawall 10 sinks.

[0051] The technical scope of the present invention is not limited to the embodiments described above, and modifications can be made as appropriate without departing from the spirit of the invention. [Explanation of Symbols]

[0052] D1 1st direction D2 2nd direction 10 Existing rubble slope embankment 11 Rubble layer 12 Protective layer 13. Waterproof sheet 20. Revetment structures 30 Caisson Structures 31 Caisson 31A Lower caisson 31B Upper caisson 31C Caisson on the side of the revetment structure 31D Existing structure side caisson 31a Bottom surface 31b Top surface 32 Filling 33,33A,33B,33C Wall section 34 Upper and lower joint section 35, 36, 37, 38 Vertical joint 39C wife wall 40 Impermeable improved substrate 50 Existing revetment 100 Revetment Structure C, C1, C2, C3 gaps

Claims

1. The existing rubble sloping embankment slopes from the existing seawall towards the impermeable improved foundation on the seaward side, A revetment structure placed on the aforementioned impermeable improved foundation, A caisson structure is positioned on the aforementioned existing rubble sloping embankment, connected to the aforementioned revetment structure, and extends in a first direction toward the aforementioned existing revetment. Equipped with, The aforementioned caisson structure is The caisson is arranged to lay a waterproof sheet on the existing rubble sloping embankment and has walls at both ends in a second direction perpendicular to the first direction and along the horizontal plane, and a filling material is provided between the walls of the caisson, and a plurality of the caissons are arranged so as to be connectable in the vertical direction. Seawall structure.

2. The caisson structure is provided with a plurality of caissons connected in the vertical direction. The revetment structure according to claim 1.

3. In the aforementioned caisson structure, the caisson positioned at the lowest end has a shape in which its lower surface is inclined along the existing rubble sloping embankment. The revetment structure according to claim 2.

4. The aforementioned existing rubble sloping embankment comprises a rubble layer in which multiple rubble stones are stacked, a protective layer placed on the upper surface of the rubble layer, and the waterproof sheet placed on the upper surface of the protective layer. The caisson structure is placed on the waterproof sheet, and the bottom of the filling is connected to the waterproof sheet. The revetment structure according to claim 1.

5. The caisson structure is arranged such that a plurality of the caissons are connected to each other along the first direction. The revetment structure according to claim 1.

6. The caisson structure has a joint portion through which the caisson located on one side in the first direction connects to the caisson located on the other side in the first direction. The revetment structure according to claim 5.

7. The joint portion is positioned with a gap in the first direction and the second direction relative to the other side of the caisson. The revetment structure according to claim 6.

8. The aforementioned filling material includes one or more impermeable waterproofing materials selected from asphalt-based waterproofing materials, soil-based waterproofing materials, cement-based waterproofing materials, and chemical-based waterproofing materials. The revetment structure according to claim 1.

9. The aforementioned filler includes rubble The revetment structure according to claim 8.

10. A repair method for repairing a revetment structure as described in claim 1, A new caisson is connected to the upper part of the existing caisson. The new filling material is filled between the walls of the new caisson and on top of the filling material between the walls of the existing caisson. Repair methods for seawall structures.

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