JP2018127834A - Foundation reinforcing structure, reinforced foundation structure, and method for reinforcing foundation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely reinforce an existing foundation structure while reducing the use of steel materials.SOLUTION: A foundation reinforcing structure 12, which reinforces an existing foundation structure 11, is formed by a plurality of steel sheet piles 19 and comprises a wall body 16 surrounding the existing foundation structure 11, a steel pipe pile 17 disposed adjacent to the wall body 16 between the existing foundation structure 11 and wall body 16, and a connection member 18 connecting the existing foundation structure 11 and the steel pipe pile 17.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a foundation reinforcing structure, a reinforcing foundation structure, and a foundation reinforcing method.

For example, when reinforcing existing foundation structures such as bridge piers provided in rivers, the additional pile method and steel pipe sheet pile foundation method are applied.
In the additional pile construction method (Non-patent Document 1), after the working space is secured by temporarily closing the periphery of the foundation with temporary steel sheet piles, a pile is constructed around the existing foundation structure, and the pile is then installed by footing. Combine with things.
Moreover, the steel pipe sheet pile foundation construction method (nonpatent literature 2) is the construction method which enabled the deadline member and this installation member to be combined. In the steel pipe sheet pile foundation method, a steel pipe sheet pile is constructed around an existing foundation structure, and the head of the steel pipe sheet pile and the existing steel pipe head are joined by footing. In this case, the steel pipe sheet pile constructed around the existing foundation structure serves as a deadline member, and a construction space in the deadline is secured by the water stop function. In addition, the steel pipe sheet pile increases support force and horizontal resistance, and the steel pipe sheet pile also functions as a permanent member.

Michio Okahara, 1 other person, “Design and Construction of Bridge Substructure in Performance Design Era (Pile Foundation)”, Sankaido, August 2003, p. 268 Steel Pipe Pile and Steel Sheet Pile Association, “Steel Pipe Pile Foundation-Design and Construction-”, Steel Pipe Pile and Steel Sheet Pile Association, December 2009

However, in the additional pile method, the steel sheet pile is a temporary material, and the work process of drawing out after the completion of the additional pile always occurs. Furthermore, in order to close up with a steel sheet pile, it is necessary to use auxiliary members, such as a cutting beam and a bellow, and in order to ensure sufficient space for construction of an auxiliary member, the cut-off area | region by a steel sheet pile becomes large.
In the steel pipe sheet pile foundation method, it is necessary to install a steel pipe sheet pile so as to surround the existing foundation structure in order to ensure water-stopping. For this reason, the number of constructions is excessive compared to the number of required supporting force and horizontal resistance. Moreover, in order to prevent the water leak between the joints of a steel sheet pile, mortar injection | pouring is needed between joints and it becomes a construction labor.

  This invention is made | formed in view of the situation mentioned above, Comprising: It suppresses the steel material to be used and it aims at strengthening an existing foundation structure reliably.

In order to solve the above problems, the present invention proposes the following means.
A foundation reinforcement structure according to the present invention is a foundation reinforcement structure for reinforcing an existing foundation structure, and is formed of a plurality of steel sheet piles, and surrounds the existing foundation structure, and the existing foundation structure, The steel pipe pile arrange | positioned adjacent to the said wall body between the said wall bodies, and the connection member which connects the said existing foundation structure and the said steel pipe pile are provided.

In this case, the foundation reinforcing structure includes a wall body formed by a plurality of steel sheet piles. Therefore, the work space can be secured around the existing foundation structure by the steel sheet pile excellent in securing the water stoppage. In addition, at this time, even if mortar is not injected between the joints of the steel sheet piles, for example, the water stoppage can be easily increased by a swelling material or the like.
Moreover, the foundation reinforcement structure is provided with the steel pipe pile arrange | positioned between an existing foundation structure and a wall, and the connection member which connects an existing foundation structure and a steel pipe pile. Therefore, the existing foundation structure can be reinforced through the connecting member by the steel pipe pile excellent in increasing the supporting force and the horizontal force. In addition, at this time, it is not necessary to ensure water-stopping with a steel pipe pile, and since the number of steel pipe piles can be set arbitrarily, the number of steel pipe piles can be increased / decreased appropriately according to required support force and horizontal force.
Furthermore, a steel pipe pile is arranged adjacent to the wall body. Therefore, for example, the load applied to the steel pipe pile is transmitted from the steel pipe pile to the wall (steel sheet pile) via the ground regardless of whether the steel pipe pile and the wall (steel sheet pile) are connected by the connecting member. can do. Thereby, the bending stress which arises in a connection member or a steel pipe pile can be reduced. In addition, when arrange | positioning a steel pipe pile adjacent to a wall body, a press injection machine can be installed, for example in the head of a steel sheet pile, and a steel pipe pile can be press-fitted in the ground with this press injection machine.
As mentioned above, according to this foundation reinforcement structure, the existing foundation structure can be reliably reinforced while suppressing the steel material used.

  In the basic reinforcement structure according to the present invention, the steel sheet pile has a pair of flanges extending in the wall width direction of the wall body, and a pair of flanges extending in the wall thickness direction of the wall body from both ends of the flange in the wall width direction. A web, and at least a part of the steel pipe pile may be disposed in a space between the flange and the pair of webs.

  In this case, at least a part of the steel pipe pile is disposed in a space between the flange and the pair of webs. As a result, when the steel sheet pile is deformed, the load can be transmitted from the steel sheet pile to the steel pipe pile through the remaining soil between the steel sheet pile and the steel pipe pile or by the steel sheet pile contacting the steel pipe pile. And the wall body can be reliably reinforced by the steel pipe pile. Furthermore, the work space inside the wall can be easily secured.

  In the foundation reinforcing structure according to the present invention, the connecting member may connect the existing foundation structure, the steel pipe pile, and the wall body.

In this case, a connection member connects an existing foundation structure, a steel pipe pile, and a wall. Therefore, the steel sheet pile can be functioned as a structural member.
In addition, since the steel pipe piles are arranged adjacent to the wall body, the wall body can be arranged close to the existing foundation structure in the horizontal direction, and the horizontal size of the connecting member is reduced (length). The bending stress generated in the connecting member can be reduced.

  In the foundation reinforcing structure according to the present invention, the connecting member may be reinforced concrete.

  In this case, since the connecting member is reinforced concrete, it is possible to easily manufacture the connecting member that matches the shapes of the existing foundation structure and the steel pipe pile. In addition, when a connection member connects an existing foundation structure, a steel pipe pile, and a wall body, it becomes possible to utilize a wall body as a formwork at the time of concrete placement, and can place concrete easily.

  In the foundation reinforcing structure according to the present invention, the steel sheet pile may be shorter in the material axis direction than the steel pipe pile.

  In this case, the steel sheet pile is shorter in the axial direction than the steel pipe pile, and the steel pipe pile is longer in the axial direction than the steel sheet pile. Therefore, the steel sheet pile is effective in securing space and water stoppage for constructing the foundation reinforcement structure with a small amount of steel used, and the steel pipe pile is the appropriate amount of steel used, mainly supporting force It is possible to provide a basic reinforcing structure that resists horizontal force, and the steel material used in the entire basic reinforcing structure can be suppressed.

  In the foundation reinforcing structure according to the present invention, the steel pipe pile may be embedded to the support layer.

  In this case, since the steel pipe pile is embedded to the support layer, the support force of the steel pipe pile is increased, and the reinforcement by the steel pipe pile can be made effective.

  The reinforcement foundation structure according to the present invention includes an existing foundation structure and the foundation reinforcement structure.

  In this case, since the reinforcing foundation structure includes the foundation reinforcing structure, it is possible to secure the supporting force and the horizontal force while suppressing the steel material used.

  A foundation reinforcement method according to the present invention is a foundation reinforcement method for reinforcing an existing foundation structure, and a wall body forming step of forming a wall body surrounding the existing foundation structure by a plurality of steel sheet piles, and a steel pipe A steel pipe pile arrangement step of arranging a pile adjacent to the wall body between the existing foundation structure and the wall body, and a connection step of connecting the existing foundation structure and the steel pipe pile by a connecting member; .

In this case, the wall body is formed by a plurality of steel sheet piles during the wall body forming step. Therefore, the work space can be secured around the existing foundation structure by the steel sheet pile excellent in securing the water stoppage. In addition, at this time, even if mortar is not injected between the joints of the steel sheet piles, for example, the water stoppage can be easily increased by a swelling material or the like.
Moreover, in the case of a connection process, an existing foundation structure and a steel pipe pile are connected by a connection member. Therefore, the existing foundation structure can be reinforced through the connecting member by the steel pipe pile excellent in increasing the supporting force and the horizontal force. In addition, at this time, it is not necessary to ensure water-stopping with a steel pipe pile, and the number of steel pipe piles can be arbitrarily set. Therefore, the number of steel pipe piles can be appropriately increased or decreased according to the necessary support force / horizontal force.
As described above, according to this foundation reinforcing method, it is possible to reliably reinforce the existing foundation structure while suppressing the steel material used.
Moreover, a steel pipe pile is arrange | positioned adjacent to a wall body in the case of a steel pipe pile arrangement | positioning process. Therefore, in the process of this foundation reinforcement method, a wall (steel sheet pile) can be reinforced with a steel pipe pile also in the case of a connection process, for example. As a result, for example, it becomes possible to eliminate or reduce the cutting beam and the anger, and the workability can be improved. In addition, in the case of a steel pipe pile arrangement | positioning process, a press-fit machine can be installed in the head of a steel sheet pile, for example, and a steel pipe pile can be press-fit into the ground with this press-fit machine.

  The foundation reinforcing method according to the present invention may include a drawing step of drawing out the wall body after the connecting step.

  In this case, since the wall body is pulled out during the drawing step, for example, the wall body can be reused, and the steel material used can be further suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the existing foundation structure can be reinforced reliably, suppressing the steel material to be used.

It is a perspective view of the reinforcement foundation structure concerning one embodiment of the present invention. It is a top view of the reinforcement foundation structure shown in FIG. It is a longitudinal cross-sectional view of the reinforcement foundation structure shown in FIG. It is a cross-sectional view of the principal part of the reinforcement foundation structure shown in FIG. It is a longitudinal cross-sectional view of the principal part of the reinforcement foundation structure shown in FIG. It is a longitudinal cross-sectional view explaining the wall body formation process in the foundation reinforcement method which concerns on one Embodiment of this invention. It is a longitudinal cross-sectional view explaining the steel pipe pile arrangement | positioning process in the foundation reinforcement method which concerns on one Embodiment of this invention.

Hereinafter, a reinforcing foundation structure according to an embodiment of the present invention will be described with reference to FIGS. 1 to 7.
As shown in FIGS. 1 to 5, the reinforcement foundation structure (hereinafter referred to as “reinforcement foundation 10”) is provided on the ground G having water F on the ground surface G <b> 0. In the ground G, the soft ground G1 is formed in the upper part of the support ground G2 (support layer). The reinforcing foundation 10 includes an existing foundation structure (hereinafter referred to as “existing foundation 11”) and a foundation reinforcing structure (hereinafter referred to as “reinforcing structure 12”) that reinforces the existing foundation 11.

  In the present embodiment, the existing foundation 11 is a bridge pier provided on the water such as a river. The existing foundation 11 includes a pier body 13, an existing footing 14, and an existing pile 15. The existing footing 14 supports the pier body 13. The existing footing 14 is a reinforced concrete structure. The existing footing 14 is formed in a rectangular parallelepiped shape.

  A plurality of existing piles 15 are provided. As shown in FIG. 3, the existing pile 15 extends downward from the existing footing 14 and is embedded in the support ground G <b> 2. The existing pile 15 is formed of, for example, a steel pipe pile or a concrete pile. The head (upper end) of the existing pile 15 is embedded in the existing footing 14. The lower end part of the existing pile 15 is located in the support ground G2. The intermediate part located between the head of the existing pile 15 and a lower end part is located in the soft ground G1.

  The reinforcing structure 12 includes a wall body 16, a steel pipe pile 17 (an additional pile), and a connecting member 18 (an additional footing). As shown in FIGS. 1 to 3, the wall body 16 surrounds the periphery of the existing foundation 11. The wall body 16 is provided continuously over the entire circumference around the existing foundation 11. The wall body 16 is formed in a rectangular shape when viewed from above. The head of the wall body 16 is located above the water surface F0. The lower end part of the wall body 16 is located in the soft ground G1.

  As shown in FIGS. 4 and 5, the wall body 16 is formed by a plurality of steel sheet piles 19. In the illustrated example, each steel sheet pile 19 is a so-called hat-shaped steel sheet pile, but may be, for example, a so-called U-shaped steel sheet pile or Z-shaped steel sheet pile. Each steel sheet pile 19 includes a flange 20, a pair of webs 21, a pair of arms 22, and a pair of joints 23.

The flange 20 extends in the wall width direction W of the wall body 16. The flange 20 resists a load input in the wall thickness direction T of the wall body 16 and increases the bending rigidity of the wall body 16.
The pair of webs 21 extend in the wall thickness direction T from both ends of the flange 20 in the wall width direction W. In the present embodiment, each web 21 extends from the flange 20 along the wall thickness direction T toward the existing foundation 11 side. Each web 21 is inclined with respect to the wall thickness direction T. The pair of webs 21 are separated from each other as they go toward the existing foundation 11 along the wall thickness direction T. Each web 21 resists a load input in the wall width direction W and increases the shear rigidity of the wall body 16.

  Each of the pair of arms 22 extends in the wall width direction W from the end portion of the corresponding web 21. Each arm 22 extends in parallel with the flange 20. Each of the pair of joints 23 is provided at the end of the corresponding arm 22. In the steel sheet piles 19 adjacent to each other in the wall width direction W, the joints 23 are joined to each other. As a result, the wall body 16 is alternately bent in the wall thickness direction T, and is formed into a wave shape that alternately repeats peaks and valleys in a top view. The plurality of steel sheet piles 19 may be arranged so that the wall body 16 is symmetrical in the wall thickness direction T with reference to an imaginary line extending in parallel with the wall width direction W in a top view.

  The steel sheet pile 19 extends in the vertical direction. In the steel sheet pile 19, a groove-like space (hereinafter referred to as “arrangement space 19 a”) is formed between the flange 20 and the pair of webs 21. The arrangement space 19a is formed in a vertical groove shape extending in the vertical direction. The arrangement space 19a increases in the wall width direction W as it goes toward the existing foundation 11 along the wall thickness direction T.

  As shown in FIGS. 1 to 3, the steel pipe pile 17 is disposed between the existing foundation 11 and the wall body 16. The steel pipe pile 17 extends in the vertical direction. The material axis direction of the steel pipe pile 17 coincides with the material axis direction of the steel sheet pile 19. As shown in FIG. 3, the steel pipe pile 17 is longer in the material axis direction than the steel sheet pile 19. The diameter of the steel pipe pile 17 may be equal to the diameter of the existing pile 15, may be larger than the diameter of the existing pile 15, or may be smaller than the diameter of the existing pile 15 as shown in the present embodiment. Good. The steel pipe pile 17 is embedded to the support ground G2, and the lower end part of the steel pipe pile 17 is arrange | positioned in the support ground G2.

  As shown in FIG. 4, the steel pipe pile 17 is disposed adjacent to the wall body 16. The steel pipe pile 17 is closer to the wall body 16 than the existing foundation 11. At least a part of the steel pipe pile 17 is arranged in the arrangement space 19a. In this embodiment, not the whole steel pipe pile 17 but only a part is arranged in the arrangement space 19a. In other words, a part of the steel pipe pile 17 enters the corrugated valley portion formed by the wall body 16. When a part of the steel pipe pile 17 is arranged in the arrangement space 19a (valley part), when the wall body 16 is viewed from the wall width direction W, a part arranged in the arrangement space 19a in the steel pipe pile 17 is a web. 21 and overlap. At this time, a portion of the steel pipe pile 17 that is not arranged in the arrangement space 19 a protrudes from the steel sheet pile 19 in the wall thickness direction T.

  For example, the steel pipe piles 17 may be provided in the same number as the arrangement spaces 19a (valley portions) in the wall body 16, and the plurality of steel pipe piles 17 may be arranged in the corresponding arrangement spaces 19a. Further, for example, as shown in the present embodiment, every other steel pipe pile 17 may be arranged in the arrangement space 19a along the wall width direction W, and a plurality of the steel pipe piles 17 are arranged along the wall width direction W. You may arrange | position in the space 19a. That is, the steel pipe piles 17 may be arranged discretely (thinned out).

  As shown in FIG. 3, the connecting member 18 connects the existing foundation 11 and the steel pipe pile 17. In the present embodiment, the connecting member 18 connects the existing foundation 11, the steel pipe pile 17, and the wall body 16. The connecting member 18 is reinforced concrete. The connecting member 18 is formed of reinforced concrete struck between the existing footing 14 and the wall body 16. The connecting member 18 covers the side surface and the upper surface of the existing footing 14. The connecting member 18 can be changed to another shape that exhibits the required strength. For example, the connecting member 18 may cover a part of the side surface of the existing footing 14.

The connecting member 18 connects the existing foundation 11 (existing footing 14) and the head of the steel pipe pile 17 and the head of the wall body 16. Thereby, since the steel pipe pile 17 and the wall body 16 unite and resist earth pressure, water pressure, seismic force, etc., they function as a structural member. In this embodiment, although the upper surface of the connection member 18, the steel pipe pile 17, and the wall body 16 is the same surface, these upper surfaces may be continued through the level | step difference.
As shown in FIGS. 4 and 5, stud bolts 24 are arranged on the surface of the steel pipe pile 17 to which the connecting member 18 is attached and on the surface of the wall body 16 (steel sheet pile 19), respectively. The stud bolt 24 functions as a fixing means for increasing the fixing force between the steel pipe pile 17 and the wall body 16 and the connecting member 18. As the fixing means, a perforated steel plate can be used instead of the stud bolt 24.

  As shown in FIG. 3, in the reinforcement foundation 10, the existing footing 14 and the connecting member 18 form a footing (hereinafter referred to as “reinforcement footing 25”) as the entire reinforcement foundation 10. In the reinforcement foundation 10, the existing pile 15 and the steel pipe pile 17 (additional pile) extend from the reinforcement footing 25 placed in the wall body 16 toward the ground G, and the reinforcement footing 25 supports the pier body 13. Yes. In the present embodiment, a part (lower part) of the reinforcing footing 25 is disposed in the soft ground G1, and the reinforcing footing 25 protrudes upward from the ground surface G0.

  Next, the foundation reinforcement method which reinforces the existing foundation 11 with the reinforcement structure 12 is demonstrated.

First, as shown in FIG. 6, a wall forming process is performed. In the wall body forming step, the wall body 16 is formed by the plurality of steel sheet piles 19. The wall body 16 surrounds the existing foundation 11 from the outside in the horizontal direction. As a result, a work space is secured around the existing foundation 11 (existing footing 14) by the internal space 16a of the wall body 16. In the internal space 16 a, the intrusion of water F from the outside is restricted by the wall body 16.
In addition, at least a part of the internal space 16a is a planned placement area 18a where the connecting member 18 is placed. The wall body 16 extends upward from the planned placement area 18a, and the planned placement area 18a is formed by a part of the internal space 16a rather than the whole.

  Next, as shown in FIG. 7, a steel pipe pile arranging step is performed. In the steel pipe pile arranging step, the steel pipe pile 17 is arranged adjacent to the wall body 16 between the existing foundation 11 and the wall body 16. At this time, for example, a press-fitting machine is installed on the head of the steel sheet pile 19, and the steel pipe pile 17 can be press-fitted into the ground G by this press-fitting machine. In addition, the steel pipe pile 17 is extended to the upper direction of the placement plan area | region 18a of the connection member 18 similarly to the wall body 16. FIG.

  Next, a connecting step is performed. In the connecting step, the existing foundation 11 and the steel pipe pile 17 are connected by the connecting member 18. In this embodiment, the wall body 16 (steel sheet pile 19) is used as a formwork for concrete placement. At this time, a reinforcing bar (not shown) required as a structural member is arranged and concrete is placed, so that the connecting member 18 connects the existing footing 14, the steel pipe pile 17, and the wall body 16. Moreover, since the steel pipe pile 17 and the wall body 16 are extended to the upper direction of the placement plan area | region 18a of the connection member 18 as mentioned above, the steel pipe pile 17 and the wall body 16 are connected immediately after a connection process. Projecting upward from the member 18.

Next, a removal process is performed. In the removal step, portions of the steel pipe pile 17 and the wall body 16 that protrude upward from the connecting member 18 are removed. Thereby, the reinforcing structure 12 as shown in FIG. 3 is formed, the existing foundation 11 is reinforced by the reinforcing structure 12, and the reinforcing foundation 10 is formed.
In addition, when the stud bolt 24 etc. are not used for the wall body 16, you may pull out and remove the full length of the wall body direction of the wall body 16 in the removal process.

As described above, according to the reinforcement foundation 10, the reinforcement structure 12, and the foundation reinforcement method according to the present embodiment, the reinforcement structure 12 includes the wall body 16 formed by the plurality of steel sheet piles 19. Therefore, a work space can be secured around the existing foundation 11 by the steel sheet pile 19 that is excellent in securing the water stoppage. In addition, at this time, even if mortar is not injected between the joints 23 of the steel sheet pile 19, for example, the water stoppage can be easily increased by a swelling material or the like.
The reinforcing structure 12 includes a steel pipe pile 17 disposed between the existing foundation 11 and the wall body 16, and a connecting member 18 that connects the existing foundation 11 and the steel pipe pile 17. Therefore, the existing foundation 11 can be reinforced through the connecting member 18 by the steel pipe pile 17 which is excellent in increasing the supporting force and the horizontal force. At this time, it is not necessary to secure water-stopping with the steel pipe piles 17 and the number of the steel pipe piles 17 can be arbitrarily set. Can do.
Further, a steel pipe pile 17 is disposed adjacent to the wall body 16. Therefore, for example, a load applied to the steel pipe pile 17 is transferred from the steel pipe pile 17 through the ground G to the wall regardless of whether the steel pipe pile 17 and the wall body 16 (steel sheet pile 19) are connected by the connecting member 18. It can be transmitted to the body 16 (steel sheet pile 19). Thereby, the bending stress which arises in the connection member 18 and the steel pipe pile 17 can be reduced.
As mentioned above, according to this reinforcement structure 12, the existing foundation 11 can be reliably reinforced, suppressing the steel material to be used.

  Moreover, the steel pipe pile 17 is arrange | positioned adjacent to the wall body 16 in the case of a steel pipe pile arrangement | positioning process. Therefore, the wall body 16 (steel sheet pile 19) can be reinforced by the steel pipe pile 17 also in the construction process of the reinforcing structure 12 (for example, between the steel pipe pile arranging process and the connecting process). As a result, for example, it becomes possible to eliminate or reduce the cutting beam and the anger, and the workability can be improved.

  Moreover, at least one part of the steel pipe pile 17 is arrange | positioned in the arrangement | positioning space 19a. Thereby, when the steel sheet pile 19 is deformed, the steel sheet pile 19 is brought into contact with the steel pipe pile 17 through the remaining soil between the steel sheet pile 19 and the steel pipe pile 17, so that the steel pipe pile 17 The wall body 16 can be reliably reinforced by the steel pipe pile 17. Furthermore, the work space inside the wall body 16 can be easily secured.

Further, the connecting member 18 connects the existing foundation 11, the steel pipe pile 17 and the wall body 16. Therefore, the steel sheet pile 19 can be functioned as a structural member.
Moreover, since the steel pipe pile 17 is arrange | positioned adjacent to the wall body 16, the wall body 16 can be arrange | positioned in the horizontal direction to the existing foundation 11, and the magnitude | size of the horizontal direction of the connection member 18 can be made small. (The length is shortened), and the bending stress generated in the connecting member 18 can be reduced.

  Moreover, since the connection member 18 is a reinforced concrete structure, the connection member 18 matched with the shape of the existing foundation 11 and the steel pipe pile 17 can be manufactured easily. In addition, when the connection member 18 connects the existing foundation 11, the steel pipe pile 17, and the wall body 16 like this embodiment, it becomes possible to utilize the wall body 16 as a formwork at the time of concrete placement, and concrete. Can be easily placed.

Further, the steel sheet pile 19 is shorter than the steel pipe pile 17 in the material axis direction, and the steel pipe pile 17 is longer than the steel sheet pile 19 in the material axis direction. Therefore, the steel sheet pile 19 is a small amount of used steel material, and is effective in securing a space for constructing the reinforcing structure 12 and water stoppage. The steel pipe pile 17 is mainly composed of an appropriate amount of used steel material. It can be set as the reinforcement structure 12 of resisting a support force and a horizontal force, and the steel material used in the reinforcement structure 12 whole can be suppressed.
Moreover, since the steel pipe pile 17 is rooted to the support layer, the support force of the steel pipe pile 17 becomes high, and the reinforcement by the steel pipe pile 17 can be made effective.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  In the said embodiment, although the connection member 18 connects the existing foundation 11 and the wall body 16, and the wall body 16 is functioning as a structural member, this invention is not limited to this. For example, in the foundation reinforcing method, a pulling process for pulling out the wall body 16 may be performed after the connecting process. That is, as described above, the entire length of the wall body 16 in the material axis direction may be pulled out during the removing step. In this case, for example, the wall body 16 can be reused, and the steel material used can be further suppressed.

  In addition, it is possible to appropriately replace the constituent elements in the embodiment with known constituent elements without departing from the spirit of the present invention, and the above-described modified examples may be appropriately combined.

10 Reinforcement foundation (Reinforcement foundation structure)
11 Existing foundation (existing foundation structure)
12 Reinforcement structure (foundation reinforcement structure)
16 Wall 17 Steel pipe pile 18 Connecting member 19 Steel sheet pile 20 Flange 21 Web G2 Support ground (support layer)
T Wall thickness direction W Wall width direction

Claims (9)

A foundation reinforcement structure that reinforces an existing foundation structure,
A wall body formed of a plurality of steel sheet piles and surrounding the existing foundation structure;
A steel pipe pile disposed adjacent to the wall body between the existing foundation structure and the wall body,
A foundation reinforcing structure comprising: a connecting member that connects the existing foundation structure and the steel pipe pile. The steel sheet pile includes a flange extending in the wall width direction of the wall body, and a pair of webs extending in the wall thickness direction of the wall body from both ends of the flange in the wall width direction,
The foundation reinforcing structure according to claim 1, wherein at least a part of the steel pipe pile is disposed in a space between the flange and the pair of webs.   The foundation reinforcing structure according to claim 1 or 2, wherein the connecting member connects the existing foundation structure, the steel pipe pile, and the wall body.   The foundation reinforcing structure according to any one of claims 1 to 3, wherein the connecting member is a reinforced concrete structure.   The foundation reinforcement structure according to any one of claims 1 to 4, wherein the steel sheet pile is shorter than the steel pipe pile in a material axis direction.   The foundation reinforcement structure according to any one of claims 1 to 5, wherein the steel pipe pile is embedded to a support layer. An existing foundation structure,
A reinforcement foundation structure comprising: the foundation reinforcement structure according to any one of claims 1 to 6. A foundation reinforcement method for reinforcing an existing foundation structure,
A wall body forming step of forming a wall body surrounding the existing foundation structure by a plurality of steel sheet piles;
A steel pipe pile placement step of placing a steel pipe pile adjacent to the wall body between the existing foundation structure and the wall body;
The foundation reinforcement method provided with the connection process which connects the said existing foundation structure and the said steel pipe pile by a connection member.   The foundation reinforcing method according to claim 8, further comprising a drawing step of pulling out the wall body after the connecting step.

Images