JP7145678B2 - Connection structure between pile head of ready-made pile and foundation footing - Google Patents

Description

The present invention relates to a connection structure between a prefabricated pile head and a foundation footing for embedding a concrete pile in a pile hole and connecting the pile head of the prefabricated pile to a foundation footing of an upper structure.

Conventionally, it was necessary to embed a ready-made concrete pile in the pile hole and embed the pile head in the superstructure. In this case, a large number of anchor reinforcing bars are placed on prefabricated piles, and the anchor reinforcing bars are fixed within the reinforcing bars for constructing the footing of the superstructure (Patent Documents 1 and 2).

JP 2016-23538 A JP 2014-181507 A

In this case, the number of rebars for constructing the footing of the upper building is large, and there is a problem that sufficient concrete intervals cannot be secured when fixing the anchor rebars of the prefabricated piles to the rebars. In particular, when connecting the foundation beams of the upper building to prefabricated piles with high bearing strength, it was necessary to further strengthen the pile heads.

In the present invention, the pile head of a prefabricated pile is larger in diameter than the pile head and is housed in a footing pile head embedding portion in which the footing main body continues upward, and further, in the footing pile head embedding portion, a horizontal portion and a vertical portion are inserted. Since the main reinforcing bars are arranged vertically and horizontally in plan view, and the oblique reinforcing bars and core reinforcing bars are arranged in plan view, the pile head of the ready-made pile, the footing pile head embedding part, and the footing main body are integrated, Since prefabricated piles can be connected to the foundation beam, a structure that effectively utilizes the strength of the prefabricated piles can be easily realized.

That is, in the present invention, a reinforcement space sufficiently larger than the diameter of the pile head is formed around and above the pile head of a ready-made concrete pile embedded in a pile hole, and in the reinforcement space, It is a connection structure between the pile head of a prefabricated pile and a foundation footing, characterized by arranging reinforcing bars as follows.
(1) The reinforcement space has a footing pile head embedding portion around the pile head, and a footing main body portion that continues above the footing pile head embedding portion and in which the beam main reinforcement of the footing is arranged.
(2) The connecting structure has outer longitudinal main reinforcing bars, outer horizontal main reinforcing bars, oblique reinforcing bars and core reinforcing bars.
(3) The outer longitudinal main reinforcing bars are
Forming a vertical portion upward from both ends of the horizontal portion,
At the bottom of the footing pile head embedded portion and near the side wall of the footing pile head embedded portion,
The horizontal portions of the outer vertical main reinforcing bars were arranged side by side with the ready-made piles sandwiched therebetween, and the upper ends of the vertical portions of the outer vertical main reinforcing bars were positioned inside the footing main body.
(4) The outer transverse main reinforcing bars are
Forming a vertical portion upward from both ends of the horizontal portion,
At the bottom of the footing pile head embedded portion and near the side wall of the footing pile head embedded portion,
The horizontal parts of the outer vertical main reinforcing bars are arranged side by side with the prefabricated piles interposed therebetween, the upper ends of the vertical parts of the outer vertical main reinforcing bars are positioned in the footing main body, and the outer horizontal main reinforcing bars are arranged horizontally. section is perpendicular to the horizontal section of the outer longitudinal main reinforcing bar.
(5) The diagonal reinforcing bars are
In a plan view with respect to the horizontal portion of the outer vertical main reinforcing bar, each side is formed in a substantially rectangular frame shape with oblique sides,
The oblique reinforcing bars are positioned inside the horizontal parts of the outer main reinforcing bars in plan view and close to the outer periphery of the prefabricated pile in plan view, and at the horizontal parts of the outer vertical main reinforcing bars or the outer horizontal main reinforcing bars. placed at approximately the same height.
(6) The core reinforcing bars are
Both ends of a linear horizontal base are bent in the horizontal direction at substantially right angles to form horizontal ends, which are substantially U-shaped in plan view,
A vertical core reinforcing bar whose horizontal base is parallel to the horizontal portion of the outer vertical main reinforcing bar and a horizontal core reinforcing bar whose horizontal base is parallel to the horizontal portion of the outer horizontal main reinforcing bar are formed as a set.
Further, a plurality of the vertical core reinforcing bars and the horizontal core reinforcing bars are arranged at predetermined intervals in the vertical direction, and the horizontal bases of both the core reinforcing bars are arranged close to the ready-made pile in a plan view, The edges of the horizontal end portions of the core reinforcing bars are positioned around the vertical portions of the outer longitudinal main reinforcing bars in a plan view, and both core reinforcing bars at the lowest level are positioned between the outer longitudinal main reinforcing bars and the outer lateral main reinforcing bars. It was positioned at a height position around the horizontal part of the reinforcing bar.

Further, in the above, the connection structure between the pile head of the ready-made pile and the foundation footing is configured as follows.
(1) The necessary number of anchor reinforcing bars were placed on the upper end of the prefabricated pile in the previous stage, and the upper part of the anchor reinforcing bars was positioned in the upper footing reinforcement space.
(2) From both ends of the horizontal part, the vertical part was formed upward to form the inner longitudinal and inner transverse main reinforcing bars.
(3) At the bottom of the footing pile head embedded part and at a position close to the outer periphery of the prefabricated pile, the horizontal parts of the inner vertical main reinforcing bars are arranged in parallel with the prefabricated pile in between, and the inner vertical The upper portion of the vertical portion of the main rebar was positioned within the footing body.
(4) At the bottom of the footing pile head embedding part and at a position close to the outer circumference of the prefabricated pile, the horizontal parts of the inner transverse main reinforcing bars are arranged side by side with the prefabricated pile in between, and the inner Both ends of the horizontal portion of the horizontal main reinforcing bar intersect with both ends of the horizontal portion of the inner vertical main reinforcing bar, and an upper portion of the vertical portion of the inner horizontal main reinforcing bar is positioned within the footing main body.
(5) The horizontal parts of the inner vertical main reinforcing bars and the inner horizontal main reinforcing bars are crossed with the diagonal reinforcing bars in a plan view, and the corners of the diagonal reinforcing bars are positioned from the horizontal parts of the inner vertical main reinforcing bars and the inner horizontal main reinforcing bars. It was positioned outside in plan view.
(6) Both core reinforcing bars on the uppermost stage were positioned at a height above the upper end of the prefabricated pile.

Further, in the above, the connection structure between the pile head of the ready-made pile and the foundation footing is configured as follows.
(1) A vertical auxiliary reinforcing bar was placed inside each corner of the diagonal reinforcing bar.
(2) The vertical auxiliary reinforcing bars are arranged outside the horizontal parts of the inner longitudinal main reinforcing bars and outside the horizontal parts of the inner horizontal main reinforcing bars.
(3) The horizontal part of the inner longitudinal main reinforcing bar and the horizontal part of the inner reinforcing bar are arranged side by side.
(4) The horizontal part of the inner longitudinal main reinforcing bar and the horizontal part of the inner reinforcing bar are arranged side by side.

In the above, “inside in plan view” refers to the side approaching the ready-made pile (direction toward the center of the ready-made pile), and “outside in plan view” refers to the side away from the ready-made pile (radial direction from the center of the ready-made pile ).

In this invention, in addition to the outer longitudinal main reinforcing bars and the outer horizontal main reinforcing bars, the oblique reinforcing bars and the core reinforcing bars are stacked vertically to arrange the reinforcing bars. It can be effectively connected with the basic footing.

FIG. 2 is a front view of the connection structure of the present invention, omitting anchor reinforcing bars; Of the connection structure of the present invention, only anchor reinforcing bars and main reinforcing bars are shown, (a) is a plan view, and (b) is a front view. Of the connection structure of the present invention, only anchor reinforcing bars and oblique reinforcing bars are shown, (a) is a plan view, and (b) is a front view. Of the connection structure of the present invention, only anchor reinforcing bars and core reinforcing bars are shown, (a) is a plan view, and (b) is a front view. Of the connection structure of the present invention, only anchor reinforcing bars and shear reinforcing bars are shown, (a) is a plan view, and (b) is a front view. FIG. 11 is a front view showing another connecting structure of the present invention; Similarly, it is a front view showing another connection structure of the present invention. Similarly, it is a front view showing another connection structure of the present invention.

Embodiments of the present invention will be described based on the drawings.

1. Composition of each reinforcing bar

(1) Inner longitudinal main reinforcing bars, inner transverse main reinforcing bars, outer longitudinal main reinforcing bars, outer transverse main reinforcing bars

The inner vertical main reinforcing bar 1 is formed by forming vertical portions 3, 3 upward from both ends of a straight horizontal portion 2, and is configured in a horizontal U shape when viewed from the side. In addition, the inner horizontal main reinforcing bars 5 are also formed by forming vertical portions 7, 7 upward from both ends of a straight horizontal portion 6, and are configured in a horizontal U-shape when viewed from the side (Fig. 2 (a) (b). )).
Similarly, the outer longitudinal main reinforcing bars 11 are also configured to form vertical portions 13, 13 upward from both ends of a straight horizontal portion 12 to form a horizontal "U" shape when viewed from the side. Similarly, vertical portions 17 are formed upward from both ends of a linear horizontal portion 16 to form a horizontal U-shape when viewed from the side (FIGS. 2(a) and 2(b)).
The inner vertical main reinforcing bar 1, the inner horizontal main reinforcing bar 5, the outer vertical main reinforcing bar 11 and the outer horizontal main reinforcing bar 15 have the same structure.

(2) Diagonal reinforcing bars/vertical auxiliary reinforcing bars

The oblique reinforcing bars 21 are oblique to the horizontal portion 6 of the inner horizontal main reinforcing bars 5 (the same applies to the inner vertical main reinforcing bars 1, the outer vertical main reinforcing bars 11, and the outer horizontal main reinforcing bars 15) in plan view. The corners 23, 23 are rounded. The diagonal reinforcing bars 21 are used in two stages, upper and lower, and a lower diagonal reinforcing bar 21A and an upper diagonal reinforcing bar 21B are prepared (FIG. 3).
The vertical auxiliary reinforcing bars 25 are vertical short reinforcing bars arranged inside the corners 23 of the oblique reinforcing bars 21 .

(3) Shear reinforcing bars

The shear reinforcing bar 41 has the same structure as a normal shear reinforcing bar, and is formed in a substantially rectangular shape in plan view (FIGS. 5(a) and 5(b)).

(4) Vertical core reinforcing bar/horizontal core reinforcing bar

The vertical core reinforcing bars 35 are formed by horizontally bending both ends of a straight horizontal base portion 36 at approximately right angles (that is, approximately 90°) to form horizontal end portions 37, 37, which are approximately U-shaped in plan view. be. The horizontal core reinforcing bars 31 also have horizontal end portions 33, 33 formed by bending both ends of a linear horizontal base portion 32 in the horizontal direction substantially at right angles, and are substantially U-shaped in plan view (Fig. 4(a)). )(b)). It should be noted that both ends of the horizontal base portion 36 may be bent to, for example, 135° or 180° (folded) instead of being substantially right-angled (approximately 90°) (not shown).
The vertical core reinforcing bars 35 and the horizontal core reinforcing bars 31 have the same structure.
The vertical core reinforcing bars 35 are arranged in pairs so that the ready-made piles 50 are sandwiched and the horizontal bases 36, 36 are arranged in parallel on both sides in a plan view, and the horizontal core reinforcing bars 31 are also arranged so that the ready-made piles 50 are sandwiched therebetween. The horizontal bases 32, 32 are arranged in pairs on both sides in plan view, and the horizontal bases 36 of the vertical core reinforcing bars 35 and the horizontal bases 36 of the horizontal core reinforcing bars 31 are orthogonal to each other. are arranged to Therefore, the core reinforcing bars are used as a set of two vertical core reinforcing bars 35, 35 and two horizontal core reinforcing bars 31, 31 at substantially the same height (Fig. 4(a) ( b)).
In addition, the core reinforcing bars are the lowermost vertical core reinforcing bar 35A and horizontal core reinforcing bar 31A, the second vertical core reinforcing bar 35B and horizontal core reinforcing bar 31B from the bottom, and a predetermined number (here, two stages) of intermediate reinforcing bars. vertical core reinforcing bars 35C and horizontal core reinforcing bars 31C, uppermost vertical core reinforcing bars 35D and horizontal core reinforcing bars 31D (FIGS. 4(a) and 4(b)).

2. Linked structure

(1) The ready-made piles 50 used in this embodiment may be ordinary ready-made piles made of concrete. For example, a ready-made pile 50 is used which is straight from the top end to the bottom end and the pile head 51 exposed upward from the ground is also formed in a straight shape. The prefabricated pile 50 has donut-shaped end plates (steel) at the upper and lower ends and cylindrical bands (steel) that cover the outer circumference, as with a normal prefabricated pile.
As the ready-made pile 50, a so-called SC pile whose outer circumference is entirely covered with a tubular steel plate can also be used. Also, the prefabricated pile 50 is configured by connecting a single prefabricated unit pile or a required number of prefabricated unit piles.

(2) Embed the ready-made piles 50 in the excavated pile holes 72 by various methods. An arbitrary construction method such as a so-called middle excavation method of excavating the pile hole 72 while burying the ready-made pile 50 and a so-called pre-excavation method of burying the ready-made pile 5 in the pile hole 72 that has been excavated can be adopted.
Around and above the pile head 51 of the ready-made concrete pile 50, the area around the pile head 51 of the ready-made pile 50 is excavated from the ground reference surface 70 (the lower surface of the footing body 54a). A footing pile head embedded portion 54 sufficiently larger than the pile diameter is formed. The footing pile head embedding portion 54 is formed in a substantially square shape (rectangular shape) in plan view, and is formed sufficiently larger than the outer circumference of the pile head portion 51 of the ready-made pile 50 . That is, the pile head 51 of the prefabricated pile 50 is exposed in the footing pile head embedded portion 54 .
Also, here, the footing pile head embedded portion 54 is continuous with the footing body portion 54 a above the reference plane 70 . That is, the footing body portion 54a is located above the reference plane 70, and the footing pile head embedded portion 54 is located below. Further, the lower surface of the footing body portion 54a serves as a reference surface 70. As shown in FIG.
Also, here, the upper edge 56 of the footing pile head embedment portion 54 is located at or above the upper edge 52 of the prefabricated pile 50 (FIG. 1). The vertical positional relationship between the upper edge 56 of the footing pile head embedded portion 54 and the upper edge 52 of the ready-made pile 50 is arbitrary.

(3) The base ends 44 (lower ends) of the plurality of anchor reinforcing bars 43, 43 are fixed by welding to the periphery of the pile head 51 of the ready-made pile 50 (Figs. 2 to 5). The prefabricated pile 50 is generally circular in plan, and the anchor reinforcing bars 43 , 43 are arranged in a circle at equal intervals on the pile head 51 of the prefabricated pile 50 . In addition, the ready-made pile 50 is welded to the end plate (steel material) or band (steel material) located at the top of the pile in the case of a normal concrete pile, and in the case of a steel pipe covered concrete pile (SC pile), at the same position. Weld to coated steel pipe.
The anchor reinforcing bars 43, 43 can be fixed to the prefabricated piles 50 by other conventionally employed methods such as screwing to end plates instead of welding (not shown).

(4) Next, the inner longitudinal main reinforcing bar 1 and the outer longitudinal main reinforcing bar 11 are arranged (Fig. 2). That is, in the vicinity of the bottom 55 of the footing bar arrangement space 54, the horizontal part 2 of the inner vertical main reinforcing bar 1 and the horizontal part 12 of the outer vertical main reinforcing bar 11 are positioned at a predetermined distance from the bottom 55. The vertical portions 3, 13 of the reinforcing bar 1 and the outer longitudinal main reinforcing bar 11 are positioned vertically.
The inner vertical main reinforcing bars 1, 1 are arranged so that the horizontal part 2 is positioned near the ready-made pile 50 and parallel to both sides of the ready-made pile 50 (rotationally symmetrical with respect to the ready-made pile 50). . Furthermore, two inner vertical main reinforcing bars 1 are arranged in a horizontal pile, and a total of four inner vertical main reinforcing bars 1, 1 are arranged.
In addition, the outer vertical main reinforcing bar 11 is spaced a predetermined distance (usually 70 mm or more) from the inner vertical main reinforcing bar 1, and the horizontal part 12 is on the far side from the ready-made pile 50 (that is, the outer peripheral side of the footing pile head embedded part 54 ), and like the inner longitudinal main reinforcing bars 1, they are arranged in parallel on both sides of the prefabricated pile 50 (rotationally symmetrical with respect to the prefabricated pile 50). Therefore, two outer longitudinal main reinforcing bars 11, 11 are arranged.
Here, the upper ends 4, 14 of the vertical portions 3, 13 of the inner longitudinal main reinforcing bar 1 and the outer longitudinal main reinforcing bar 11 are made to be equal to the upper end 45 of the anchor reinforcing bar 43 or protrude above the upper end 45 of the anchor reinforcing bar 43 (Fig. 2(b)).

(5) Next, the inner horizontal main reinforcing bars 5 and the outer horizontal main reinforcing bars 15 are arranged (Fig. 2). That is, in the vicinity of the bottom 55 of the footing pile head embedding portion 54, it is perpendicular to the horizontal portion 2 of the inner longitudinal main reinforcing bar 1 in plan view and also perpendicular to the horizontal portion 12 of the outer longitudinal main reinforcing bar 11 in plan view. , the horizontal portions 5 of the inner horizontal main reinforcing bars 5, 5 and the horizontal portions 6 of the outer vertical main reinforcing bars 15 are positioned, and the vertical portions 7 of the inner horizontal main reinforcing bars 5 and the vertical portions 17 of the outer horizontal main reinforcing bars 15 are positioned vertically. be positioned at Further, since the horizontal portion 6 of the inner horizontal main reinforcing bar 5 and the horizontal portion 16 of the outer vertical main reinforcing bar 15 are placed on the horizontal portion 6 of the inner horizontal main reinforcing bar 5 and the horizontal portion 16 of the outer vertical main reinforcing bar 15, , tie both rebars at the crossing point.
In addition, the inner horizontal main reinforcing bars 5, 5 are arranged so that the horizontal portion 6 is positioned near the ready-made pile 50 and parallel to both sides of the ready-made pile 50 (the ready-made pile 50 rotationally symmetrical with respect to). Furthermore, two of the inner horizontal main reinforcing bars 5 are also stacked horizontally to provide a total of four inner horizontal main reinforcing bars (Fig. 2(a)).
In addition, like the outer vertical main reinforcing bars 11, the outer horizontal main reinforcing bars 15 are horizontally spaced outward from the inner horizontal main reinforcing bars 5 by a predetermined distance, and the horizontal portion 16 is on the far side from the ready-made pile 50 (that is, the footing It is arranged on the outer peripheral side of the pile head embedding part 54), and is arranged so as to be parallel on both sides of the ready-made pile 50 (rotationally symmetrical with respect to the ready-made pile 50) in the same way as the inner horizontal main reinforcing bar 5. Therefore, two lateral main reinforcing bars 15 are also arranged (FIG. 2(a)).
Here, the upper end 8 of the vertical portion 7 of the inner horizontal main reinforcing bar 5 and the upper end 18 of the vertical portion 16 of the outer horizontal main reinforcing bar 15 are also equal to the upper end 45 of the anchor reinforcing bar 43 or protrude above the upper end 45 of the anchor reinforcing bar 43. Let The fixing length of the anchor reinforcing bars 43 is determined according to the desired strength, the number of anchor reinforcing bars, etc., as in the conventional case.

(6) In addition, all or part of the shear reinforcing bars 41, 41 to be used are removed while the inner longitudinal main reinforcing bar 1, the outer longitudinal main reinforcing bar 11, the inner horizontal main reinforcing bar 5, and the outer horizontal main reinforcing bar 15 are arranged. , are bundled near the bottom 55 of the footing pile head embedded part 54 so as to surround the vertical parts 3, 7, 13, 17 of the main reinforcing bars (not shown). Incidentally, the structure and construction of the shear reinforcing bars 41, 41 are the same as the conventional ones, and can be constructed by other procedures (not shown).

(7) Subsequently, the lower diagonal reinforcing bars 21A are placed (FIG. 3). That is, in the footing pile head embedded portion 54, the lower slanted reinforcing bars 21A are arranged on the horizontal portions 6 of the inner horizontal main reinforcing bars 5, 5 and on the horizontal portions 16 of the outer horizontal main reinforcing bars 15, 15. Each side 22, 22 of the diagonal reinforcing bar 21A is arranged to obliquely intersect both the horizontal portions 6, 16 (here, about 45°) in plan view.
Here, the corners 23, 23 of the oblique reinforcing bar 21A are located between the horizontal part 6 of the inner horizontal main reinforcing bar 5 and the horizontal part 16 of the outer horizontal main reinforcing bar 15 in plan view (Fig. 2(a)). . Further, auxiliary vertical reinforcing bars 25, 25 are arranged so as to contact the inner edge of each corner 23, 23 of the diagonal reinforcing bar 21A, and each corner 23 of the diagonal reinforcing bar 21A and the auxiliary vertical reinforcing bar 25 are bound. Therefore, the auxiliary vertical reinforcing bars 25, 25 are also positioned between the horizontal portion 6 of the inner horizontal main reinforcing bar 5 and the horizontal portion 16 of the outer horizontal main reinforcing bar 15 in plan view (Fig. 2(a)).
The corners 23 of the oblique reinforcing bars 21A and the auxiliary vertical reinforcing bars 25 can be fixed in advance by binding or the like.
In addition, the oblique reinforcing bars 21 are defined as "horizontal portions 2, 6, 12, 16 of the main reinforcing bars 1, 5, 11, 15" and/or "horizontal bases 32, 36 of the core reinforcing bars 31, 35, which will be described later." It is desirable to fix them by tying or the like.
Also, although the diagonal reinforcing bars 21A and 21B are provided in two stages, they may be provided in three or more stages, or in one stage with only one of the upper stage and the lower stage (not shown).

(8) Subsequently, a set of core reinforcing bars (two vertical core reinforcing bars 31A and two horizontal core reinforcing bars 35A) are arranged (Fig. 4). That is, in the footing pile head embedded part 54, two horizontal core reinforcing bars 31A, 31A are arranged on the lower diagonal reinforcing bar 21A, and then the vertical core reinforcing bars 35A are placed on the upper horizontal core reinforcing bars 31A, 31A. 35A is placed.
Here, the parallel horizontal base portions 32, 32 of the horizontal core reinforcing bars 31A are parallel to the horizontal portions 6 of the inner horizontal main reinforcing bars 5 and the horizontal portions 16 of the outer horizontal main reinforcing bars 15, and are the most ready-made piles 50 in plan view. It is arranged at a position closer to the ready-made pile 50 than the horizontal part 6 of the inner horizontal main reinforcing bar 5 close to. In addition, the parallel horizontal bases 36, 36 of the vertical core reinforcing bars 35A, 35A are parallel to the horizontal part 2 of the inner vertical main reinforcing bar 1 and the horizontal part 12 of the outer vertical main reinforcing bar 11, and are the most ready-made piles in plan view. It is arranged at a position closer to the ready-made pile 50 than the horizontal part 2 of the inner vertical main reinforcing bar 1 near 50 . The horizontal bases 32, 36 of both the core reinforcing bars 31, 35 are desirably arranged on the side closer to the ready-made pile 50, but are arranged inside the horizontal parts 12, 16 of the outer main reinforcing bars 11, 15 in plan view. If so, the installation position is arbitrary.
Therefore, here, the horizontal base portion 32 of the horizontal core reinforcing bar 31A and the horizontal base portion 36 of the vertical core reinforcing bar 35 cross each side 22, 22 of the diagonal reinforcing bar 21D obliquely (approximately 45°).
In addition, the edge 34 of the horizontal end portion 33 of the horizontal core reinforcing bar 31A and the edge 38 of the horizontal end portion 37 of the vertical core reinforcing bar 35A are the corners of the footing pile head embedded portion 54 (that is, the outer edge) in plan view. They are located near the vertical portion 13 of the longitudinal main iron 11 and the vertical portion 17 of the outer horizontal main reinforcing bars 15), and are arranged with a gap between them so that they do not contact each other (Fig. 4(a), Fig. 2(a)). .
At this time, both ends of the horizontal base portions 32 and 35 of the horizontal core reinforcing bars 31A and the vertical core reinforcing bars 35A (around the bending points to the horizontal ends 33 and 36) are, in plan view, the footing pile head embedded portions 54. (that is, the horizontal portion 12 of the outer longitudinal main iron 11 and the horizontal portion 16 of the outer transverse main reinforcing bar 15). The features of this arrangement are common even if the bending angles (90°, 135°, 180°, etc.) of the horizontal ends 33, 36 are different.
Further, the horizontal base portion 36 of the vertical core reinforcing bar 35A and the horizontal base portion 32 of the horizontal core reinforcing bar 31A are bound together at the intersecting position.
Moreover, although the horizontal bases 32 and 36 of both the core reinforcing bars 31 and 35 are arranged near the prefabricated pile 50 in plan view, they can be arranged apart from the prefabricated pile 50 (not shown). Further, the edges 34, 38 of the horizontal ends 33, 37 of the core reinforcing bars 31, 35 are arranged at the corners of the footing pile head embedded part 54 in plan view, but they can be arranged at other positions ( not shown). It should be noted that this is common to both core reinforcing bars 31 and 35 in each stage. Further, both the core reinforcing bars 31 and 35 are arranged so that each stage is at substantially the same position in a plan view, but the positions can be shifted (not shown).

(9) Subsequently, the upper diagonal reinforcing bars 21B are placed (FIG. 3). That is, in the footing pile head embedded part 54, the upper diagonal reinforcing bar 21B is arranged on the lowermost set of core reinforcing bars (horizontal core reinforcing bar 31B, vertical core reinforcing bar 25B). The upper diagonal reinforcing bar 21B is arranged at substantially the same position as the lower diagonal reinforcing bar 21A in plan view.
Therefore, the corners 23, 23 of the diagonal reinforcing bar 21A are located between the horizontal part 6 of the inner horizontal main reinforcing bar 5 and the horizontal part 16 of the outer horizontal main reinforcing bar 15 in plan view, similarly to the diagonal reinforcing bar 21B. Also, the inner edges of the corners 23, 23 of the oblique reinforcing bars 21B are arranged so as to contact the auxiliary vertical reinforcing bars 25, 25. As shown in FIG.
Note that the anchor reinforcing bars 43, 43 are positioned inside the diagonal reinforcing bars 21A, 21B in plan view.
Further, the corners 23, 23 (auxiliary vertical reinforcing bars 25, 25) of the oblique reinforcing bars 21A, 21B are located outside (the side away from the ready-made pile 50) the horizontal bases 32, 36 of the core reinforcing bars 31A, 35A. (21A and 21B indicated by dashed lines in FIG. 4(a)).

(10) Subsequently, a set of core reinforcing bars (horizontal core reinforcing bars 31B and vertical core reinforcing bars 35B) in the second stage is arranged (Fig. 4). That is, in the footing pile head embedding part 54, the second horizontal core reinforcing bars 31B and 31B are arranged above the upper diagonal reinforcing bar 21B at a predetermined distance (with a slight distance), and above it. Vertical core reinforcing bars 35B, 35B are arranged.
The horizontal core reinforcing bars 31B and the vertical core reinforcing bars 35B are arranged at substantially the same positions as the horizontal core reinforcing bars 31A and the vertical core reinforcing bars 35A of the first stage in plan view.
Therefore, like the horizontal core reinforcing bars 31A and the vertical core reinforcing bars 35A, the parallel horizontal bases 32, 32 of the horizontal core reinforcing bars 31B are the horizontal portions 6 of the inner horizontal main reinforcing bars 5 and the horizontal portions of the outer horizontal main reinforcing bars 15. It is parallel to the portion 16 and arranged at a position closer to the ready-made pile 50 than the horizontal portion 6 of the inner horizontal main reinforcing bar 5 closest to the ready-made pile 50 in plan view. In addition, the parallel horizontal bases 36, 36 of the vertical core reinforcing bars 35B, 35B are parallel to the horizontal part 2 of the inner vertical main reinforcing bar 1 and the horizontal part 12 of the outer vertical main reinforcing bar 11, and are the most ready-made piles in plan view. It is arranged at a position closer to the ready-made pile 50 than the horizontal part 2 of the inner vertical main reinforcing bar 1 near 50 . In addition, the edge 34 of the horizontal end 33 of the horizontal core reinforcing bar 31B and the edge 38 of the horizontal end 37 of the vertical core reinforcing bar 35B are the corners of the footing pile head embedded part 54 (that is, the It is positioned near the vertical portion 13 of the two longitudinal main irons 11 and the vertical portion 17 of the outer horizontal main reinforcing bars 15), and is arranged with a gap that does not contact each other (Fig. 4(a), Fig. 2(a)). ). Further, the horizontal base portion 36 of the vertical core reinforcing bar 35A and the horizontal base portion 32 of the horizontal core reinforcing bar 31A are bound together at the intersecting position.
Also, the edge of the horizontal end 33 of the horizontal core reinforcing bar 31A and the edge of the horizontal end 37 of the vertical core reinforcing bar 35A are attached to the vertical portion 13 of the second vertical main iron 11 and/or the outer horizontal main iron. It is fixed to the vertical portion 17 of the reinforcing bar 15 by binding or welding to the extent that it does not move.

(11) Subsequently, a predetermined number of core reinforcing bars 31 and 35 other than the third stage are arranged in the footing pile head embedded portion 54 (Fig. 4). In this embodiment, above the second stage core reinforcing bar (horizontal core reinforcing bar 31B, vertical core reinforcing bar 35B), a predetermined distance is provided above the third stage core reinforcing bar (horizontal core reinforcing bar 31C, vertical core reinforcing bar 35B). core reinforcing bar 35C), a predetermined distance above it, the fourth stage core reinforcing bar (horizontal core reinforcing bar 31D, vertical core reinforcing bar 35D), and a predetermined distance above it, the fifth stage core reinforcing bars (horizontal core reinforcing bars 31E, vertical core reinforcing bars 35E) are placed.
In the above, the third stage core reinforcement (horizontal core reinforcement 31C, vertical core reinforcement 35C), the fourth stage core reinforcement (horizontal core reinforcement 31D, vertical core reinforcement 35D), the middle of the fifth stage The child reinforcing bars (horizontal core reinforcing bars 31E and vertical core reinforcing bars 35E) have the same structure as the horizontal core reinforcing bars 31A and 31B and the vertical core reinforcing bars 35A and 35B, and are arranged at substantially the same position in plan view. .
Further, the vertical distances of the respective core reinforcing bars (horizontal core reinforcing bars 31A to 31E and vertical core reinforcing bars 35A to 35E) are set to be substantially the same, and they are arranged at substantially equal intervals in the vertical direction.
In addition, the core reinforcing bars in the uppermost stage, that is, the core reinforcing bars in the fifth stage (horizontal core reinforcing bars 31E, vertical core reinforcing bars 35E) are positioned above the upper edge 52 of the prefabricated pile 50 and embedded in the footing pile head. It is housed within the portion 54 .

(12) Subsequently, a predetermined number of shear reinforcing reinforcing bars 41 are arranged in the footing pile head embedded portion 54 (Fig. 5). In the same manner as a normal shear reinforcing reinforcing bar arrangement work, the shear reinforcing reinforcing bars 41 bundled near the bottom 55 of the footing pile head embedded portion 54 are lifted upward, and the inner vertical main reinforcing bar 1 and the outer vertical main reinforcing bar 11 are lifted. , the inner horizontal main reinforcing bars 5 and the outer horizontal main reinforcing bars 15, the shear reinforcing bars 41, 41 are arranged so as to surround the vertical portions 3, 7, 13, 17 of the main reinforcing bars 41, 41, respectively. Ties to the vertical sections 3, 7, 13, 17 of the main rebar.
In addition, when only a part of the shear reinforcing reinforcing bars 41 are bundled near the bottom 55 of the footing pile head embedded part 54, the remaining shear reinforcing reinforcing bars 41, 41 are bundled from above, the inner vertical main reinforcing bar 1, the outer vertical main reinforcing bar 1, and the outer vertical main reinforcing bar 1 from above. The reinforcing bars 11, the inner horizontal main reinforcing bars 5 and the outer horizontal reinforcing bars 15 are arranged so as to surround the vertical portions 3, 7, 13 and 17 of the main reinforcing bars.
The shear reinforcing bars 41, 41 that have been completely arranged are arranged at substantially equal intervals in the vertical direction, and the lowest shear reinforcing bar 41 is the lower end portion of each of the vertical portions 3, 7, 13, 17 of each main reinforcing bar. It is arranged at a height position in the vicinity (near the lower diagonal reinforcing bar 21A, the first horizontal core reinforcing bar 31A, and the vertical core reinforcing bar 35A). Further, the topmost shear reinforcing bar 41 is positioned at the upper end of each vertical portion 3, 7, 13, 17 of each main reinforcing bar (Fig. 1).

(13) After or during the work of (1) to (12), inside the footing body portion 54a above the upper edge 52 of the ready-made pile 50 (above the upper edge 56 of the footing pile head embedded portion 54) , the main reinforcing bars 61, 61 of the foundation beams (foundation footings) of the upper building are arranged in the same manner as in the past, and other necessary reinforcements are arranged in the same manner as in the past. Anchor with the vertical parts 3, 7, 13, 17, etc. of the rebar (Fig. 1).
As described above, the connection structure 60 between the pile head and the foundation footing is constructed (Fig. 1).

3. Other connecting structures 60

(1) In the above embodiment, the inner longitudinal main reinforcing bars 1 and the inner horizontal main reinforcing bars 5 are arranged in close proximity to each other, with a total of four on each side of the ready-made pile 50. There could be more than one, or one per side (not shown). Also, the inner vertical main reinforcing bars 1 and the inner horizontal main reinforcing bars 5 can be omitted (not shown).
In addition, the outer vertical main reinforcing bars 11 and the outer horizontal main reinforcing bars 15 are arranged one on each side of the ready-made pile 50, a total of two, but it is also possible to arrange two or more on one side and four or more on both sides ( not shown).

(2) In the above embodiment, the vertical portions 3, 8, 13, 18 of the outer longitudinal main reinforcing bar 11, the outer horizontal main reinforcing bar 15, the inner longitudinal main reinforcing bar 1, and the inner horizontal main reinforcing bar 5 are sufficiently constrained. If so, the shear reinforcing bar 41 can be omitted (not shown).

(3) In the above-described embodiment, the oblique reinforcing bars 21 are arranged in two stages, and the horizontal core reinforcing bars 31 and the vertical core reinforcing bars 35 are arranged in five stages. Other stages are also possible.
In addition, the height of the footing pile head embedding portion 54 is reduced (the area of the footing pile head embedding portion 54 in plan view is also reduced), and the pile head 51 of the ready-made pile 50 extends from the bottom 55 of the footing pile head embedding portion 54 . can also be formed to have a small projecting height (FIG. 6). In this case, the lower slanted reinforcing bar 21A, the first tier core reinforcing bar (horizontal core reinforcing bar 31A, vertical core reinforcing bar 35A), the second tier core reinforcing bar (horizontal core reinforcing bar 31A, vertical core reinforcing bar 31A, vertical core reinforcing bar 35A), A secondary reinforcing bar 35A) is formed in the same manner as in the above-described embodiment, and two levels of core reinforcing bars are arranged thereon. That is, the uppermost stage is arranged with the fourth stage core reinforcing bar (horizontal core reinforcing bar 31D, vertical core reinforcing bar 35D) and above the upper end 52 of the ready-made pile 50, and the third stage core reinforcing bar is arranged below it. (Horizontal core reinforcing bar 31C, vertical core reinforcing bar 35C) are arranged (Fig. 6).

(4) In the above embodiment, the ready-made pile 50 has a straight structure, but the structure of the ready-made pile is arbitrary, and the ready-made pile 50 having the large diameter portion 53 formed at the upper end can also be used. (Fig. 7).
For example, the large-diameter portion 53 can be formed from the upper end of the prefabricated pile 50 to reach the shaft portion 50a via the shape-changing portion 53a (so-called ST pile). In this case, the upper end portion of the shaft portion 50a directly below the large-diameter portion 53 of the ready-made pile 50, the shape-changing portion 53a, and the large-diameter portion 53 are exposed in the footing pile head embedded portion . In addition, the horizontal portion 2 of the inner vertical main reinforcing bar 1, the horizontal portion 6 of the inner horizontal main reinforcing bar 5, the lower diagonal reinforcing bar 21A, the first core reinforcing bar (horizontal core reinforcing bar 31A, vertical core reinforcing bar 35A), and The upper diagonal reinforcing bar 21B is positioned below the large-diameter portion 53 (the upper end portion of the shaft portion 50a, the shape-changing portion 53a) (FIGS. 7, 2 to 4). Further, in plan view, the oblique reinforcing bars 21A and 21B are arranged on the outer peripheral side of the large diameter portion 53 (FIGS. 7 and 3).
In addition, the shape ( A so-called knot pile) can also be used (Fig. 8). In this case also, the upper end portion of the shaft portion 50a directly below the large diameter portion 53 of the prefabricated pile 50, the shape changing portion 53a, the large diameter portion 53, and the shape changing portion 53b are exposed in the footing pile head embedded portion . In addition, the horizontal portion 2 of the inner vertical main reinforcing bar 1, the horizontal portion 6 of the inner horizontal main reinforcing bar 5, the lower diagonal reinforcing bar 21A, the first core reinforcing bar (horizontal core reinforcing bar 31A, vertical core reinforcing bar 35A), and The upper diagonal reinforcing bar 21B is positioned below the large-diameter portion 53 (the upper end portion of the shaft portion 50a, the shape-changing portion 53a) (FIGS. 7B and 2 to 4). Further, in plan view, the oblique reinforcing bars 21A and 21B are arranged on the outer peripheral side of the large diameter portion 53 (FIGS. 8 and 3).

1 Inner vertical main reinforcing bar 2 Horizontal part (inner vertical main reinforcing bar)
3 Vertical part (inner vertical main reinforcing bar)
4 Upper end of vertical part (inner longitudinal main reinforcing bar)
5 Inner horizontal main reinforcing bar 6 Horizontal part (inner horizontal main reinforcing bar)
7 Vertical section (inner horizontal main reinforcing bar)
8 Upper end of vertical section (inner transverse main reinforcing bar)
11 Outer vertical main reinforcing bar 12 Horizontal part (outer vertical main reinforcing bar)
13 Vertical section (outer longitudinal main reinforcing bar)
14 Upper end of vertical section (outer longitudinal main reinforcing bar)
15 Outer horizontal main reinforcing bar 16 Horizontal part (outer horizontal main reinforcing bar)
17 vertical section (outer transverse main reinforcing bar)
18 Upper end of vertical section (outer transverse main reinforcing bar)
21 Diagonal reinforcing bar 21A Diagonal reinforcing bar (bottom row)
21B diagonal rebar (middle)
21C diagonal rebar (top)
22 side part (diagonal reinforcing bar)
23 corner (diagonal reinforcing bar)
25 Vertical auxiliary reinforcing bar (diagonal reinforcing bar)
31 Horizontal core reinforcing bar 31A Horizontal core reinforcing bar (bottom row)
31B Horizontal core reinforcing bars (lower two stages)
31C Horizontal core reinforcing bar (middle)
31D Horizontal core reinforcing bar (top stage)
32 Horizontal base (horizontal core rebar)
33 horizontal end (horizontal core rebar)
34 tip (horizontal core reinforcing bar)
35 Vertical core reinforcing bar 35A Vertical core reinforcing bar (bottom row)
35B Vertical core reinforcing bars (lower two stages)
35C Vertical core rebar (middle)
35D Vertical core reinforcing bar (top stage)
36 Horizontal base (horizontal core rebar)
37 horizontal end (horizontal core rebar)
38 tip (horizontal core reinforcing bar)
41 Shear reinforcement reinforcing bar 43 Anchor reinforcing bar 44 Base of anchor reinforcing bar 45 Upper end of anchor reinforcing bar 50 Ready-made pile 50a Shaft portion of ready-made pile 51 Pile head of ready-made pile 53 Large-diameter portion of ready-made pile 53a Shape change portion of ready-made pile (bottom)
53b Shape change part of ready-made pile (upper)
54 footing pile head embedded part (space)
54a Footing body (space)
55 bottom of footing pile head embedded part 56 upper edge 60 connection structure of footing pile head embedded part
61 Main rebar for foundation beam 70 Reference surface 72 Pile hole

Claims (3)

A reinforcement space sufficiently larger than the diameter of the pile head is formed around and above the pile head of the prefabricated concrete pile embedded in the pile hole, and the following reinforcing bars are placed in the reinforcement space. A connection structure between a pile head of a prefabricated pile and a foundation footing, characterized in that the reinforcement is arranged.
(1) The reinforcement space has a footing pile head embedding portion around the pile head, and a footing main body portion that continues above the footing pile head embedding portion and in which the beam main reinforcement of the footing is arranged.
(2) The connecting structure has outer longitudinal main reinforcing bars, outer horizontal main reinforcing bars, oblique reinforcing bars and core reinforcing bars.
(3) The outer longitudinal main reinforcing bars are
Forming a vertical portion upward from both ends of the horizontal portion,
At the bottom of the footing pile head embedded portion and near the side wall of the footing pile head embedded portion,
The horizontal portions of the outer vertical main reinforcing bars were arranged side by side with the ready-made piles sandwiched therebetween, and the upper ends of the vertical portions of the outer vertical main reinforcing bars were positioned inside the footing main body.
(4) The outer transverse main reinforcing bars are
Forming a vertical portion upward from both ends of the horizontal portion,
At the bottom of the footing pile head embedded portion and near the side wall of the footing pile head embedded portion,
The horizontal parts of the outer vertical main reinforcing bars are arranged side by side with the prefabricated piles interposed therebetween, the upper ends of the vertical parts of the outer vertical main reinforcing bars are positioned in the footing main body, and the outer horizontal main reinforcing bars are arranged horizontally. section is perpendicular to the horizontal section of the outer longitudinal main reinforcing bar.
(5) The diagonal reinforcing bars are
In a plan view with respect to the horizontal portion of the outer vertical main reinforcing bar, each side is formed in a substantially rectangular frame shape with oblique sides,
The oblique reinforcing bars are positioned inside the horizontal parts of the outer main reinforcing bars in plan view and close to the outer periphery of the prefabricated pile in plan view, and at the horizontal parts of the outer vertical main reinforcing bars or the outer horizontal main reinforcing bars. placed at approximately the same height.
(6) The core reinforcing bars are
Both ends of a linear horizontal base are bent in the horizontal direction at substantially right angles to form horizontal ends, which are substantially U-shaped in plan view,
A vertical core reinforcing bar whose horizontal base is parallel to the horizontal portion of the outer vertical main reinforcing bar and a horizontal core reinforcing bar whose horizontal base is parallel to the horizontal portion of the outer horizontal main reinforcing bar are formed as a set.
Further, a plurality of the vertical core reinforcing bars and the horizontal core reinforcing bars are arranged at predetermined intervals in the vertical direction, and the horizontal bases of both the core reinforcing bars are arranged close to the ready-made pile in a plan view, The edges of the horizontal ends of the core reinforcing bars are positioned around the vertical portions of the outer longitudinal main reinforcing bars in a plan view, and both the core reinforcing bars at the lowest level are positioned between the outer longitudinal main reinforcing bars and the outer lateral main reinforcing bars. It was positioned at a height position around the horizontal part of the reinforcing bar. The connecting structure of the pile head of the prefabricated pile and the foundation footing according to claim 1, characterized in that it is configured as follows.
(1) The necessary number of anchor reinforcing bars were placed on the upper end of the prefabricated pile in the previous stage, and the upper part of the anchor reinforcing bars was positioned in the upper footing reinforcement space.
(2) From both ends of the horizontal part, the vertical part was formed upward to form the inner longitudinal and inner transverse main reinforcing bars.
(3) At the bottom of the footing pile head embedded part and at a position close to the outer periphery of the prefabricated pile, the horizontal parts of the inner vertical main reinforcing bars are arranged in parallel with the prefabricated pile in between, and the inner vertical The upper portion of the vertical portion of the main rebar was positioned within the footing body.
(4) At the bottom of the footing pile head embedding part and at a position close to the outer circumference of the prefabricated pile, the horizontal parts of the inner transverse main reinforcing bars are arranged side by side with the prefabricated pile in between, and the inner Both ends of the horizontal portion of the horizontal main reinforcing bar intersect with both ends of the horizontal portion of the inner vertical main reinforcing bar, and an upper portion of the vertical portion of the inner horizontal main reinforcing bar is positioned within the footing main body.
(5) The horizontal parts of the inner vertical main reinforcing bars and the inner horizontal main reinforcing bars are crossed with the diagonal reinforcing bars in a plan view, and the corners of the diagonal reinforcing bars are positioned from the horizontal parts of the inner vertical main reinforcing bars and the inner horizontal main reinforcing bars. It was positioned outside in plan view.
(6) Both core reinforcing bars on the uppermost stage were positioned at a height above the upper end of the prefabricated pile. The connecting structure of the pile head of the ready-made pile and the foundation footing according to claim 2, characterized in that it is configured as follows.
(1) A vertical auxiliary reinforcing bar was placed inside each corner of the diagonal reinforcing bar.
(2) The vertical auxiliary reinforcing bars are arranged outside the horizontal parts of the inner longitudinal main reinforcing bars and outside the horizontal parts of the inner horizontal main reinforcing bars.
(3) The horizontal part of the inner longitudinal main reinforcing bar and the horizontal part of the inner reinforcing bar are arranged side by side.
(4) The horizontal part of the inner longitudinal main reinforcing bar and the horizontal part of the inner reinforcing bar are arranged side by side.

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