JP2003160943A - Pile head coupled structure, joining structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce damage of the joint between a pile head and a foundation base upon occurring of an earthquake and the like, and simplify construction work and reduce construction period. <P>SOLUTION: Steel stress dispersing boards 1 and viscoelastic materials (acrylic polymer viscoelastic materials) 45 are laminated alternately on an elastic material (urethane elastomer) 44, and the lower surface of the upper lid 39 of a protective cylinder 37 is placed on the upper-most viscoelastic material 45 to form a joining structure 47. Reinforcing bars 22 are arranged to be projected on the upper surface of the upper lid. A gap 41 is formed on the pile head of a concrete pile 6, which is capped with the joining structure 47, and the elastic material 44 is placed on an end face plate 13. Then, footing concrete is filled in such a way that the concrete does not penetrate the protective cylinder 37, and the pile head of the concrete pile 6 is joined to the footing 28, thus a pile head coupled structure 30 is formed (a). In this pile head coupled structure 30, a horizontal force P<SB>1</SB>can be absorbed by the deformation of viscoelastic material 45 and the move of the stress dispersing board 1 (b). Also, forces of drawing or plucking can be absorbed by the expansion/contraction of the viscoelastic material 45 and the elastic material 44. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a building and civil engineering structure, in which a pile head of a pile structure buried in the ground is fixed to a foundation base such as footing of an upper structure and is joined thereto. Also, the present invention relates to a connecting structure forming a main part of a pile head connecting structure.

[0002]

2. Description of the Related Art Conventionally, as a connection structure between a pile head of a pile body buried in the ground and a foundation base, a steel structure (for example, a deformed rebar or an anchor bolt) for connecting to the upper end portion of the pile structure or a site constructed pile is used. Etc.), and the structure in which this steel material is fixed to the concrete in the foundation base has been generally adopted.

[0003]

When a large external force is applied during an earthquake or the like, this external force concentrates on the pile head and the foundation base, and in the conventional pile head connection structure, the pile head is There was a problem that external force could not be dispersed and the pile head and foundation base were damaged.

[0004] In order to solve this problem, a seismic isolation foundation using a damper device for structures is known. However, in this damper device, it takes time and labor to install the device, and the construction cost becomes high. There was a point.

As another structure, there is also known a structure in which the connection between the pile head and the foundation base is slid on each other to distribute the external force. In this structure, since the sliding part is unbonded with the pile head or the foundation base, it is difficult to recover the positional relationship between the pile head and the foundation base after the pile head moves due to external force. Was becoming.

[0006]

According to the present invention, however, the pile head of the pile structure is fixed to the foundation base via the stress dispersion plate and the viscoelastic plate, so that the above-mentioned problems can be solved easily. (EN) Provided is a pile head connecting structure capable of dispersing and absorbing an external force at the pile head.

That is, the invention of the pile head connecting structure is a structure in which the pile head of the pile structure is embedded in the foundation base, and an annular stress distribution board is provided on the upper surface of the pile head of the pile structure. Attaching a connecting structure formed by stacking one or more sheets, and attaching a reinforcing bar for fixing the base to the upper surface of the connecting structure,
The pile head connection structure is characterized in that the pile head is fixed in a foundation base.

Further, in the above, the pile head connection structure is characterized in that the structural rebar embedded in the pile structure and a plurality of stress distribution boards are integrally fixed. Further, the pile head connecting structure is characterized in that the end face plate of the pile head of the pile structure and a plurality of stress distribution boards are connected by bolts.

Another invention of a pile head connecting structure is a structure in which a pile head of a pile structure is embedded in a foundation base, and an annular stress distribution board is provided on an upper surface of the pile head of the pile structure. And a resilient plate are alternately laminated and fixed, and a connecting structure is fixed, and the pile head is fixed in the foundation base.

Another invention of a pile head connecting structure is a structure in which a pile head of a pile structure is embedded in a foundation base.
On the upper surface of the pile head of the pile structure, a coupling structure formed by alternately stacking an annular stress distribution board and a viscoelastic board is arranged, and the pile head is fixed in the foundation base. It is a pile head connection structure characterized in that.

Further, in the above, the top surface of the coupling structure is covered and fixed with a capped cylindrical protection cylinder, covers the outer periphery of the coupling structure, and the outer surface of the protection cylinder serves as the base base. It is a pile head connection structure characterized by being fixed.
Further, it is a pile head connection structure in which a reinforcing bar for fixing the base is projected on the outer wall of the connecting structure or the protective cylinder.

Another invention of a pile head connecting structure is a structure in which a pile head of a pile structure is embedded in a foundation base, and an elastic board is fixed to an upper surface of the pile head of the pile structure. On the upper surface of the elastic plate, a connecting structure, in which a stress dispersion plate and a viscoelastic plate are alternately laminated and arranged, is fixed, and a capped cylindrical protective cylinder is covered on the connecting structure. The pile head connecting structure is characterized in that the outer circumference of the pile head is covered and the outer surface of the protective cylinder is fixed to the foundation base.

Further, the invention of the connecting structure is formed by laminating a plurality of stress dispersion discs made of steel, or laminating an elastic body and / or a viscoelastic body on the stress dispersion discs to form a laminated portion. Then, the lower surface of the laminated portion can be fixed to the pile structure, and the upper surface of the laminated portion is on the lower surface of the top plate of the protective tubular body having a cylindrical top with which the pile head of the pile structure can be covered. The connecting structure is characterized in that it is fixed and a predetermined gap is formed between the outer wall of the laminated portion and the inner wall of the protective cylinder. Furthermore, another invention is a coupling structure characterized in that an elastic body is interposed between the outer wall of the laminated portion and the inner wall of the protective cylinder.

The foundation base in the above means the lower end of the upper structure joined to the upper end (pile head) of the pile structure such as footing (footing foundation) or solid foundation.

Further, the "pile structure" in the above means mainly a ready-made concrete pile in which various steel materials (rebars, PC steel rods, etc.) are buried, and a so-called SC pile in which a steel pipe is coated on the outer periphery. Is also included. Moreover, the present invention can be applied to a ready-made pile having a steel material as a main structure such as a so-called steel pipe pile as the “ready-made pile”. In addition, when a plurality of ready-made piles are joined to each other at the top and bottom to be used, it can be applied to a case where a ready-made pile of different materials is combined to form a pile structure. Further, the present invention can be similarly applied to so-called on-site constructed piles in addition to ready-made piles. Moreover, when using the ready-made piles, the method of burying the ready-made piles such as the pre-boring method and the medium excavation method is optional.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION (1) The stress distribution board of the present invention is made of a material having the same strength as the end plate of the pile.
The planar shape is also formed into a similar donut shape. Multiple layers of this stress disperser are laminated and fixed integrally to the upper end face plate of the concrete prefabricated pile, the pile head is embedded in the footing together with the stress disperser, and the pile head is fixed to the footing. Constitute. In this case, the stress distribution board may be fixed to the rebar cage of the ready-made pile in advance at the time of manufacturing the ready-made pile, or the stress dispersion board may be laminated and fixed to any ready-made pile afterwards. Also, when fixing the stress distribution board after the fact,
It is also possible to fix the ready-made piles at the time of factory shipment, or to stack and fix the stress distribution boards before or after burying the ready-made piles at the construction site.

The prefabricated pile is preferably a concrete prefabricated pile having a pile end plate because the effect of the stress distribution board can be most exerted, but it can also be applied to steel pipe piles, and
It can also be applied to various field construction piles.

(2) Further, instead of laminating the stress dispersion discs alone, a viscoelastic body or an elastic body, or both elastic bodies and viscoelastic bodies are alternately laminated between the stress dispersion discs. It can also be configured. In this case, the pile head is covered with a protective cylinder so that the elastic body and viscoelastic body can be deformed, and the inner wall of the protective cylinder, the laminated elastic body, viscoelastic body, and outer circumference of the stress dispersion plate are covered. It is necessary to configure such that a gap is formed between the wall and the wall. And in construction,
It is necessary to prevent the foundation base concrete from entering the gap of the protective cylinder. Further, various cushioning materials, for example, an elastic body used for lamination with a stress dispersion board can be interposed in this gap. In this case, it is possible to absorb the lateral movements of the laminated stress distributor, elastic body, and annual elastic body.

[0019]

Embodiment 1 An embodiment of the present invention will be described with reference to FIGS.

[1] Construction of ready-made piles

The production of a concrete pile in which a plurality of stress distribution boards 1 and 1 are integrated will be described.

The stress distributors 1 and 1 used in this embodiment
Is made of steel and has the same planar shape as the shape of the upper end face plate 13 of the concrete pile, and is formed in a donut shape having the same thickness as the upper end face plate 13. Stress distribution board 1, 1
Has a hollow portion 2 corresponding to the hollow portion 14 of the upper end face plate 13, and is provided for the PC steel rod 8 at a position corresponding to the insertion hole 3 for the PC steel rod 8 of the upper end face plate 13 (a position where communication is possible). An insertion hole 3 is formed. The insertion hole 3 has a large diameter on the upper side, and forms a housing portion 4 capable of housing nuts.

Structural rebars that form the framework of concrete piles,
PC steel rod is knitted as a rebar cage 7. The PC steel rod 8 of the rebar cage 7 has a connecting portion 9 formed by increasing the upper end portion by the length L of the thickness of the stress distribution board, and the upper screw thread portion 1 is provided above the connecting portion 9.
Form 0. Further, with the PC steel rod 8, a screw thread is formed on the outer surface corresponding to the position of the upper end face plate 13, and the intermediate screw portion 11
And A nut 18 for preventing deviation is screwed into the intermediate thread portion 11 of the PC steel rod 8 (FIG. 1 (c)).

Upper end plate used (same for lower end plate) 13
An insertion hole 15 for the PC steel rod 8 is formed in the. The upper end face plate 13 is attached to the rebar cage 7 while inserting the PC steel rods 8 and 8 through the insertion holes 15 and 15. The upper end plate 13 is P
It is locked to the nut 18 of the intermediate thread portion 11 of the C steel rod 8. Also, in the lower end plate, the PC steel rod 8
The other end of is fixed (not shown).

On the upper end face plate side, five stress dispersion plates 1 and 1 are stacked in series (in the length direction of the pile), and the respective connecting portions 9 of the PC steel rods 8 and 8 are inserted into the insertion holes 3 for the PC steel rods. Then, the fixing nut 20 is screwed into the connecting portion 9 of the PC steel rod 8 and is accommodated in the accommodating portion 4 of the stress distribution board 1a located at the uppermost position. With the above, the rebar cage 7, the upper end face plate 13, the lower end face plate, the stress distribution discs 1, 1a
Are joined together. A reinforcing band 19 for covering the concrete portion of the pile head is wound below the upper end face plate 13. The inner circumference of the upper end of the reinforcing band 19 is fixed to the outer peripheral surface of the upper end face plate 13.

At this time, it is preferable to apply grease or the like in order to prevent water or the like from entering between the stress dispersion boards 1 and 1, prevent rust, and obtain a lubricating effect.

Subsequently, a rebar cage 7 in which the stress dispersion plates 1, 1, the upper end face plate 13 and the lower end face plate are integrated is installed in a predetermined molding frame, and concrete is filled and centrifugal molding is performed. At this time, the nuts 18, 20 attached to the PC steel rod 8
As a result, the stress spreaders 1 and 1 are held at a predetermined position together with the upper end face plate 13, so that the stress spreaders 1 and 1 can be prevented from moving to the rebar cage 7 side during manufacturing.

After that, by performing a predetermined curing and then removing from the mold, a concrete pile 25 in which the five stress dispersion boards 1 and 1 are integrally connected can be constructed (FIGS. 1 (a) and 1 (b)).

[2] Pile head connection structure

The concrete pile 25 thus formed is used as a single pile or an upper pile of a connecting pile. The concrete pile 25 is buried at a predetermined depth by the pre-boring method, the medium excavation method, or the like. Then, the ground is excavated to expose the pile head 26 from the new ground. After cleaning the pile head 26, the reinforcing bars (including anchor bolts etc.) for fixing inside the footing are placed on the stress distribution board 1a located at the top of the pile head 26.
Install 22, 22.

The rebars 22, 22 for fixing in the footing described above are attached to the upper surface of the uppermost stress distribution board 1a by welding, or the uppermost stress distribution board 1a or a plurality of other stress distribution boards is preliminarily attached. It is also possible to provide bolt holes in 1 and 1 and screw the rebar into the bolt holes for mounting (not shown). It is optional to use another method.

On the pile head 26 of the concrete pile 25 thus formed, a form for forming footing is installed, and if concrete is poured (not shown), the pile head 26 and footing 28 will be separated. Integrated pile head connection structure 3
0 can be constructed (Fig. 2).

As described above, by using the concrete piles 25 on which the stress distribution boards 1 and 1 are installed at the joints with the footings 28, even if a large horizontal force is applied during an earthquake, a plurality of It can be absorbed by the relative movement of the stress distribution boards 1, 1. Therefore, the degree of damage can be reduced at the joint between the pile head 26 and the footing 28, which are relatively damaged.

[3] Other Embodiments

In the above embodiment, the concrete pile 25
Although the reinforcing bars 22 and 22 are used to fix the pile head 26 and the footing 28 of the above, the steel pipe having a hollow portion may be fixed to the uppermost stress distribution board 1a (not shown). ). At this time, if ribs are provided on the inner surface and / or the outer surface of the steel pipe, the adhesion of the footing 28 to the concrete can be increased.

Further, in the above-mentioned embodiment, the stress dispersion boards 1, 1 are used.
Although 5 sheets were used, the thickness and the number of sheets can be arbitrarily set in consideration of the load of the upper structure, the type of pile to be used, the ground property, and the like.

In the above embodiment, the thickness of the stress distribution board 1 is preferably the same in order to make the forces acting on the stress distribution plates 1 and 1 substantially uniform, and the same as the upper end face plate 13. Therefore, the force acting on the pile head 26 including the upper end face plate 13 can be made substantially uniform.
The thickness may be different from 3, and the thickness of each stress distribution board may be different (not shown).

Further, the planar shapes (outer diameter, inner diameter) of the stress dispersion boards 1 and 1 are substantially the same and the same as the upper end face plate 13. Therefore, similarly, the stress dispersion plates 1 including the upper end face plate 13 are also included. The forces acting on 1, can be substantially uniform, which is advantageous, but can also have different shapes (not shown).

[0039]

[Embodiment 2] Another embodiment of the present invention will be described with reference to FIGS. This embodiment is an embodiment in which a stress distribution board is fixed to a conventional ready-made pile later and used, and a protective cylinder 37 is used for fixing with footing.

[1] Construction of ready-made piles

Stress dispersers 1 and 1 used in this embodiment
Is the same as in the first embodiment. That is, it is made of doughnut-shaped steel having the same planar shape and thickness as the shape of the upper end face plate 13 of the concrete pile. The stress distribution board 1 has a hollow portion 2 corresponding to the hollow portion 14 of the upper end face plate 13, and screw holes 5 and 5 are formed at positions (communication positions) corresponding to the bolt holes of the upper end face plate 13. There is. The screw hole 5 of the stress distribution board 1a located at the uppermost position is configured such that the upper side (upper surface side) is expanded in diameter to form the accommodating portion 4, so that the head portion of the nut or the bolt can be accommodated (see FIG. d)).

The concrete pile 6 used in this embodiment is a conventional concrete pile. That is, the upper end surface plate 13 of the concrete pile 6 is adjacent to the bolt hole 31 for inserting the PC steel rod, and the fixing hole 32 having the locking edge for fixing the PC steel rod is formed. A pair of bolt holes 31 and fixing holes 32 that are adjacent to each other communicate with each other in the circumferential direction and are formed in a planar gourd shape.

In manufacturing the concrete pile 6, when the reinforcing bar cage 7 and the upper end face plate 13 are assembled, the upper end face plate 13
The PC steel rod 8 is inserted into each of the bolt holes 31 and 31 of the above. In this state, rotate the upper end plate 13 and the lower end plate to
The steel rods 8 and 8 are displaced toward the fixing hole 32 side, and the bulging portion 12 at the tip of the PC steel rod 8 is locked to the locking edge of the fixing hole 32 and fixed to the upper end face plate 13 (FIG. 3 (d)). ). Therefore, after fixing, the bolt holes 31 of the upper end face plate 13 are free.

Next, the five stress distribution boards 1, 1 are stacked on the upper end face plate 13 of the concrete pile 6, and the bolts 34 are screwed from the screw holes 5, 5 of the stress distribution boards 1, 1 located at the top. ,
The bolt 34 is screwed into the screw holes 5 and 5 that are vertically communicated with the stress distribution boards 1 and 1, and the tip portion 35 of the bolt 34 is screwed.
Is screwed into the bolt hole 31 of the upper end face plate 14. Therefore,
The upper end face plate 13 and the stress distribution boards 1, 1 are bolts 34, 3
By means of 4, they are integrally screwed and tightly connected (FIG. 3 (d)).

The joining of the concrete pile 6 and the stress distribution boards 1, 1 in the above may be carried out in advance at a manufacturing factory or at the construction site of the pile. Therefore,
Even after the concrete pile 6 is manufactured, the number of stress distribution boards can be appropriately selected according to the load of the ground structure, the ground property, and the like. Further, after embedding the concrete pile 6, the pile head is exposed and washed, and then the stress distribution boards 1, 1 are attached to the upper end face plate 13 of the concrete pile 6,
It is also possible to construct the concrete pile 25.

[2] Pile head connection structure

A donut having an opening 40 having a diameter smaller than the outer diameter of the stress distributor 1 at the upper end of a cylindrical main body 38 having a hollow portion (inner diameter) larger than the outer diameter of the stress distributor 1. A steel tube-shaped protective cylinder 37 to which a circular upper lid (top plate) 39 is integrally attached is configured. The inner diameter of the protection cylinder 37 is the upper end face plate 13 of the concrete pile 6 (25) and the stress distribution board 1
It has a larger diameter than the above. The axial length of the tubular main body 38 is, for example, about 10 cm to about the outer diameter of the pile to be used.

A protective cylinder 37 is put on the upper surface of the stress distribution board 1a located at the top of the concrete pile 25, and the stress distribution boards 1 and 1 are arranged so as to cover the stress dispersion boards 1 and 1. Next, the rebars 22, 22 for fixing the footing are fixed on the stress distribution board 1a located at the top through the opening 40 of the upper lid 39 of the protection cylinder 37. A cushioning material (rubber, gravel, etc.) 42 is filled in the gap between the outer surface of the stress distribution board 1 and the inner wall of the protective cylinder 37.

Next, a formwork for constructing a footing is assembled, concrete is poured, and a footing 28 is constructed. Then, a pile head connecting structure 30 in which the pile head 26 of the concrete pile 25 is fixedly connected to the footing 28 is constructed. (FIG. 4A).

In this way, the plurality of stress distribution boards 1,
The concrete pile 25 on which No. 1 is installed should be absorbed by the relative movement of the plurality of stress dispersion boards 1, 1 even when a large horizontal force is applied during an earthquake, as in the case of the first embodiment. You can Therefore, the degree of damage can be reduced at the joint between the pile head 26 and the footing 28, which are relatively damaged.

Further, when the protective cylinder 37 is used,
In addition to the absorption effect of the plurality of stress distribution boards 1 and 1, the stress absorption effect of the cushioning material 42 can be obtained.

Naturally, the protective cylinder 37 and the cushioning material 42
The connection structure using is the concrete pile 25 of Example 1.
Can also be applied to.

[3] Other Embodiments

In the above-mentioned embodiment, the other embodiment of the stress distributor 1 is the same as that of the first embodiment.

In the above embodiment, a plurality of stress distribution boards 1 were joined using the bolt holes 31 for inserting the PC steel rod of the upper end face plate 13 of the concrete pile 6, but the upper end face plate 13 was bolted. A bolt hole for screwing may be separately provided (not shown).

Further, in the above embodiment, the protective cylinder 37
Since the tubular main body 38 is cylindrical, it is desirable from the viewpoint that the pile has a circular cross-sectional shape and that the stress acts evenly, but it may be a rectangular tube or a hexagonal tube.
In this case, the shape of the upper lid 39 is also formed into a flat quadrangle, a hexagon or the like (not shown).

Further, in the above-mentioned embodiment, the upper end face plate 13 of the concrete pile 6 and the stress distribution boards 1 and 1 are screwed and fastened by the normal bolts 34, but other bolts may be used. For example, the bulging portion (head side) 54 and the threaded portion (tip side) 55 may be connected by a high-strength spring 56 to form the bolt 53 (FIG. 10A). Also,
It is also possible to construct the bolt 53 by further connecting the bulging portion 54 and the threaded portion 55 with the shaft portion 57 made of an elastic body with the bolt 53 (FIG. 10B). That is, the structure is such that the high-strength spring 56 is fitted on the outer side of the shaft portion 57 made of an elastic body.

By using the bolts 53, 53 having the spring 56 in the middle portion in this manner, the relative movement of the plurality of stress distribution boards 1, 1 can be facilitated, and an external force excessively generated during an earthquake or the like can be prevented. The effect of dispersion / absorption can be improved. Further, the shaft portion 57 made of an elastic body is provided at the center of the spring 56 to form the bolt 53, thereby functioning as a damper and mainly when a compressive load is applied to the bolts 53, 53. Then, the shaft portions 57, 57 made of an elastic body expand and contract to absorb an impact load, and have an absorbing effect of about 1.5 times as compared with the case where only the spring 56 is used.

[0059]

Third Embodiment Another embodiment of the present invention will be described with reference to FIGS. In this embodiment, the elastic body 44 is provided on the upper surface of the pile head.
A pile head connecting structure in which the stress dispersion board 1 and the viscoelastic body 45 are alternately laminated on top of each other will be described.

[1] Pile head connection structure

(1) "Elastic body" used in this embodiment
As the material, a urethane elastomer having a density of about 0.35 to 0.5 (g / cm ³ ) and a fine cell foam structure is used. Since this urethane elastomer has a foamed structure, stress is applied relatively uniformly during compression, and it is less likely to deteriorate even when subjected to repeated compressive loads, and has excellent durability.

The "viscoelastic body" used in this example
Is made of an acrylic polymer having excellent shearing force.

The protective cylinder 37 used in this embodiment is also used.
Has the same structure as that of the second embodiment, except that from the upper lid 39 to the opening 4
This is a structure in which 0 is omitted. That is, the cylindrical main body 3 having a hollow portion (inner diameter) larger than the outer diameter of the stress distributor 1
A circular upper lid (top plate) 39 is integrally attached to the upper end of the steel pipe 7. The inner diameter of the protection cylinder body 37 is formed to be larger than the upper end face plate 13 of the concrete pile 6 (25), the stress distribution board 1, and the like.

(2) First, an elastic member having a predetermined thickness (for example, about one-third of the outer diameter of a ready-made pile, depending on the load of the upper structure, etc.) and having substantially the same plane shape as the end face plate. On the body (urethane elastomer) 44, the first stress distribution board 1 having a size equal to or larger than the outer diameter of the elastic body 44 is fixed with an adhesive or the like.

Then, a first member having an outer diameter substantially the same as that of the elastic body 44 and a predetermined thickness (for example, about 1/6 of the outer diameter of the ready-made piles depends on the load of the upper structure, etc.). The viscoelastic body (acrylic polymer viscoelastic body) 45 is fixed. Viscoelastic body 45
Since it has adhesiveness, it can be brought into close contact by applying a predetermined pressure without using a fixing means such as an adhesive.

The first stress dispersion board 1 and the first viscoelastic body 45 are set as one set, and three sets are fixed.

Then, on the uppermost third elastic body 45,
The protective cylinder 37 is arranged and the upper lid 39 is fixed. Top lid 3
Reinforcing bars 22, 22 for fixing footing are projected on the upper surface of 9 to form a connecting structure 47 (FIG. 5A). A gap 41 is formed between the inner side of the tubular main body 38 of the protective tubular body 37 and the outer surface of the elastic body 44 (the viscoelastic body 45, the stress distributor 1). A cushioning material may be interposed in the gap 41 as in the second embodiment (not shown).

[2] Pile head connection structure

(1) The concrete pile 6 is buried by any conventionally known construction method such as the pre-boring method and the hollow excavation method, the pile head of the concrete pile 6 is exposed, and the pile head is washed.

Next, the concrete pile 6 is covered with the connecting structure 47, and the lower surface of the elastic body 44 is set on the upper end face plate 13 of the concrete pile 6. The upper surface of the upper end plate and the lower surface of the elastic body 44 of the combined structure are fixed to each other with an adhesive or the like.

In order to align the core with the upper end face plate 13 of the concrete pile 6 and fix it accurately, for example, the following guide cylinder 49 is used (FIG. 9).

The guide cylinder 49 is composed of guide cylinder pieces 49a and 49b obtained by dividing a cylinder into halves, one edge of which is rotatably joined, and the horizontal flanges 50a and 50 are formed on the outer surface of the other end.
b are respectively projected (FIG. 9 (b)). Flange 50
When a and 50b are vertically stacked, the flanges 50a and 50b
The through holes of b are communicated with each other, and the pin 52 can be inserted into the through holes to prevent the guide cylinder pieces 49a and 49b from opening (FIG. 9A).
(C)).

That is, the guide cylinder pieces 49a and 49b are previously attached to the outer surface of the pile head of the concrete pile 6, and the pins 52 are detachably temporarily fixed (FIGS. 8, 9A and 9C). Insert the upper ends of the guide cylinder pieces 49a and 49b into the concrete pile 6
Is projected above the upper end of the. From above, the connecting structure 47 is lowered, and the elastic body 44 and the like are attached to the guide tube pieces 49a, 4a.
9b, the lower surface of the elastic body 44 is attached to the upper end face plate 1
Stick to 3. Then, the pin 52 is pulled out, and the guide cylinder pieces 49a and 49b are removed from the concrete pile 6.

(2) A formwork for footing construction is installed on the connecting structure 47 fixed to the pile head of the concrete pile 6, and concrete is poured into the protective cylinder 37 so that concrete does not enter. The pile head of the concrete pile 6 and the footing 28 are connected to each other to form the pile head connection structure 30.

(3) In the pile head connecting structure 30 of the pile head of the concrete pile 6 and the footing 28 thus formed, even when a large horizontal force P ₁ is applied during an earthquake, Within the gap 1 between the side surface of the viscoelastic body 45 in the protection cylinder 37 and the inner wall of the protection cylinder 37, the viscoelastic body 45 and the like can be moved relative to each other and the stress can be absorbed (FIG. 5).
(B)). Since the viscoelastic body 45 has the properties of rubber and clay together, it tries to return to the current state with the properties of rubber, but slowly returns with the properties of clay. This flexible property can prevent damage to the pile head of the concrete pile 6 and the footing 28.

In addition, the pulling force P in the event of an earthquake_TwoWhen the
Even if it is the case, the viscoelastic body 44 expands with the pulling force and
Withdrawal force P_TwoReturns and compressive force P with building load_ThreeWorks
In this case, the compression deformation of the elastic body 44 is mainly caused by the gap 4
This compression force P is made within 1. _ThreeCan absorb
(Fig. 6).

[3] Other Embodiments

In the above embodiment, the number of sets in which the stress distributor 1 and the viscoelastic body 45 are laminated, or the elastic body 44.
The thickness, the thickness of the viscoelastic body 45, and the thickness of the stress distribution board 1 are appropriately selected and adopted depending on the load of the upper structure, the ground property, and the like.

Another embodiment of the protective cylinder 37 in the above embodiment is the same as that in the second embodiment.

Further, in the above-mentioned embodiment, the connecting structure 47 was formed in advance and attached to the washed concrete pile 6 at the construction site, but the elastic body 44,
The stress dispersion board 1, the viscoelastic body 45, the protective cylinder 37, etc. may be laminated and fixed to the concrete pile 6, respectively.

Further, in the above-described embodiment, the elastic structure 44 and the viscoelastic body 45 are used together to form the connecting structure 47. However, the elastic body 44 and the stress distribution board 1 are alternately laminated and combined. The pile head connection structure 30 can also be constructed by constructing the structure 47 for use (FIG. 7A). Alternatively, the viscoelastic body 45 and the stress distribution board 1 may be alternately laminated to configure the connecting structure 47 to construct the pile head connecting structure 30 (FIG. 7B).

[0082]

EFFECTS OF THE INVENTION By using a pile structure in which a plurality of stress distribution boards are stacked on the pile head for connection with a foundation base, a relatively large horizontal force is applied by the stress distribution board. Even if there is, there is an effect that the stress can be absorbed by the relative movement of the stress distribution board, and the damage at the joint between the pile head and the foundation base can be reduced.

An elastic body was fixed to the pile head, and a stress dispersion plate and a viscoelastic body were alternately laminated and fixed on the elastic body.
By connecting the pile head and the foundation base, horizontal force and pulling force can be absorbed due to the extension characteristics of the viscoelastic body,
Also, the expansion effect of the elastic body can absorb the compression force,
This has the effect of reducing damage to the pile head and foundation base.

When the laminated portion is previously fixed to the protective cylinder capable of covering the pile head to form the connecting structure, the pile head joint structure can be easily constructed and the work can be simplified. It is effective to reduce the construction period.

[Brief description of drawings]

FIG. 1 is a ready-made pile used in Embodiment 1 of the present invention,
(A) is a plan view, (b) is a partially broken front view,
(C) is an exploded view showing the configuration.

FIG. 2 is a vertical cross-sectional view of the pile head connection structure according to the first embodiment.

FIG. 3 is a ready-made pile used in Example 2 of the present invention,
(A) is a plan view, (b) is a partially broken front view,
(C) is sectional drawing in the AA line of (b), (d) is an expanded longitudinal sectional view.

FIG. 4A is a vertical cross-sectional view of the pile head connecting structure of the second embodiment, and FIG. 4B is a cross-sectional view taken along line BB of FIG. 4A.
(C) is sectional drawing in the CC line | wire of (a).

5A is a vertical cross-sectional view of a pile head connection structure according to a third embodiment of the present invention, and FIG. 5B is a vertical cross-sectional view when a horizontal force is similarly applied.

FIG. 6 is a vertical cross-sectional view of the pile head connection structure when similarly subjected to vertical load.

FIG. 7 is a vertical sectional view of another pile head connection structure according to the third embodiment.

FIG. 8 is a schematic perspective view illustrating a guide cylinder used for implementing the third embodiment.

9A and 9B are also guide tubes, FIG. 9A is a plan view in a closed state, FIG. 9B is a plan view in an open state, and FIG. 9C is a D in FIG. 9B.
-Enlarged sectional view taken along line D

10A and 10B are front views of a bolt used in the second embodiment and the like.

[Explanation of symbols]

1 stress distribution board 1a Stress distributor (top) 2 Hollow part of the stress distributor 3 Insertion hole for stress distribution board 4 Stress Dispersion Disk Housing 5 Screw holes on the stress distribution board 6 Concrete piles (conventional) 8 PC steel rod 9 PC steel bar connection 10 PC steel rod upper thread 11 PC steel rod middle thread 13 End plate 18 Nut (intermediate screw part) 20 Nut (upper thread) 22 Reinforcing bar for footing fixing 25 concrete pile (with stress distribution board) 26 pile head 28 footing (basic basis) 30 pile head connection structure 34 Volts 37 Protective cylinder 38 tubular body 39 Upper lid 41 Gap 42 cushioning material 44 Elastic body 45 Viscoelastic body 47 Coupling structure 49 Guide tube

Claims (10)

[Claims] 1. A structure in which a pile head of a pile structure is embedded in a foundation base, wherein one or a plurality of annular stress distribution boards are superposed on the top surface of the pile head of the pile structure. A pile head connecting structure, wherein a connecting structure is attached, and a reinforcing bar for fixing a base is attached to an upper surface of the connecting structure to fix the pile head inside the base. 2. The pile head connection structure according to claim 1, wherein the structural rebar embedded in the pile structure and a plurality of stress distribution boards are integrally fixed. 3. The pile head connection structure according to claim 1, wherein the end face plate of the pile head of the pile structure and a plurality of stress distribution boards are connected by bolts. 4. A structure in which a pile head of a pile structure is embedded in a foundation base, wherein an annular stress dispersion plate and an elastic plate are alternately laminated on the upper surface of the pile head of the pile structure. Fix the connecting structure
A pile head connection structure, wherein the pile head is fixed in the foundation base. 5. A structure in which a pile head of a pile structure is embedded in a foundation base, and an annular stress dispersion disk and a viscoelastic disk are alternately laminated on the upper surface of the pile head of the pile structure. A pile head connecting structure, wherein a connecting structure is formed and the pile head is fixed in the foundation base. 6. The top surface of the coupling structure is covered and fixed with a capped cylindrical protection cylinder, and covers the outer periphery of the coupling structure.
The pile head connection structure according to claim 1, 4, 5 or 6, wherein an outer surface of the protection cylinder is fixed to the foundation base. 7. The pile head connecting structure according to claim 6, wherein a reinforcing bar for fixing the base is projected on an outer wall of the connecting structure or the protective cylinder. 8. A structure in which a pile head of a pile structure is embedded in a foundation base, wherein an elastic board is fixed to an upper surface of the pile head of the pile structure, and a stress dispersion board is provided on an upper surface of the elastic board. And a viscoelastic disc are alternately laminated to each other to fix the connecting structure, and the connecting structure is covered with a protective cylinder having a cylindrical top to cover the outer periphery of the pile head,
A pile head connection structure, wherein an outer surface of the protective cylinder is fixed to the foundation base. 9. A plurality of stress dispersion discs made of steel material are laminated, or an elastic body and / or a viscoelastic body are laminated on the stress dispersion disc to form a laminated part, and a lower surface of the laminated part is formed. It is fixable to a pile structure, and the upper surface of the laminated portion is fixed to the lower surface of the top plate of the protective cylinder having a tubular shape with a top that can cover the pile head of the pile structure, and the laminated portion A coupling structure characterized in that a predetermined gap is formed between the outer wall and the inner wall of the protective cylinder. 10. The coupling structure according to claim 9, wherein an elastic body is interposed between the outer wall of the laminated portion and the inner wall of the protective cylinder.