JP2017095888A - Steel column-pile junction structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a column-pile junction structure, which can ensure sufficient antivibration performance of a column.SOLUTION: A column-pile junction structure 1 is a structure of a joint between a steel column 20 and a pile 10. A steel connection member 30 having an upper plate 32 is installed at an upper end of the structure. The upper plate 32 of a connection member 30 is connected to a lower end of the steel column 20. The lower end of the connection member 30 is buried in a concrete body 12 inside the pile 10. According to the column-pile junction structure 1, positioning of an installation position of the steel column 20 can be easily carried out and the structure has an excellent toughness due to smooth transmission of a force generated in an upper structure to the pile.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a joint structure between a steel column and a pile having a reinforced concrete pile head, for example.

Conventionally, as a joint structure between a steel column and a pile, it has been proposed to provide a connecting member (temporary support member) between the steel column and the pile (see Patent Document 1).
In Patent Document 1, the upper end of a temporary support member is bolted to a steel column, and the lower end of the temporary support member is bolted to a joining plate that is welded to a pile head. In addition, foundation footing is provided from below the pile head surface to above the lower end surface of the steel column, and the vertical bars constituting the foundation footing are dense from below the pile head surface to above the lower end surface of the steel column. The bar is arranged.

  Patent Document 2 discloses that anchor bolts connected to a fixing plate are driven into the column base foundation concrete, thereby securing the pull-out strength of the anchor bolts.

JP 2012-57430 A Japanese Patent No. 4575019

  In Patent Document 1, when a pulling force acts on a steel column, this pulling force is transmitted from the steel column to the vertical bars constituting the concrete foundation footing, and is transmitted to the piles through the vertical bars. The Therefore, since high tensile stress is generated in the vertical bars, there is a possibility that cracks may occur along the vertical bars. Further, in a steel column to which a high pulling force is applied, it is necessary to arrange the vertical and horizontal bars constituting the foundation footing with high density, and the foundation footing tends to be enlarged.

  Moreover, in patent document 1, the temporary support material was installed in the upper end surface of a pile, the plate was provided in the upper end surface of this temporary support material, and the steel column was fixed on this plate. Therefore, it is necessary to insert and adjust the height adjustment material between the steel column and the plate to determine the installation position and installation adjustment of the steel column, ensuring the positioning of the installation height and the installation accuracy. It took a lot of time.

  In patent document 2, in order to fix a steel column, the column base foundation concrete provided with the wide part exceeding a steel column was required, and the freedom degree of design was restrict | limited when planning arrangement | positioning of a steel column.

  The present invention provides a steel pillar-pile joint structure that has an excellent toughness by allowing the steel column to be easily positioned and the force generated in the superstructure to be smoothly transmitted to the pile. The task is to do.

  1st invention is the structure of the junction part of steel pillars (for example, below-mentioned steel pillars 20 and 20A) and a pile (for example, below-mentioned pile 10), Comprising: A plate (for example, below-mentioned upper part) A steel connecting member (for example, connecting members 30, 30A, 30B described later) having a plate 32) is provided, and the plate of the connecting member is joined to the lower end portion of the steel column, and the lower end of the connecting member. The part is embedded in a concrete body inside the pile.

  According to 1st invention, the connection member joined to the pillar and fixed in a pile body was provided. Therefore, the height position of the column can be adjusted by adjusting the buried length of the connecting member. In addition, the connecting member is disposed between the steel column and the pile, and this connecting member is bonded to the steel column and fixed in the pile body, so that the tensile force generated in the steel connecting member is However, since it is transmitted to the vertical reinforcing bars that make up the pile, the seismic performance of the columns can be sufficiently secured. As in the prior art, it is not necessary to transmit the pulling force between the steel column and the pile by the vertical bars constituting the foundation footing, and it is not necessary to arrange the vertical bars of the foundation footing densely. Therefore, the basic footing can be reduced in size. In addition, it is easy to position the steel column in the built-in position, and the force generated in the superstructure can be smoothly transmitted to the pile to exhibit excellent toughness.

  Moreover, since the lower end part of the connection member was embed | buried under the concrete in a pile body, in addition to being restrained by the hardened concrete, the lower end part of a connection member is firmly joined to a pile by the adhesion effect | action of concrete.

  The second invention is characterized in that a stud (for example, a stud 33 described later) is provided on an outer peripheral surface of a portion embedded in the concrete body of the connecting member.

According to the second invention, since the stud is implanted in the portion of the connecting member embedded in the concrete body, the connecting member is fixed to the pile body via the stud, and the connecting member is firmly fixed to the pile body. Can do.
Moreover, a stud can be fixed to a pile body by providing a stud in a flange and / or a web according to the magnitude | size of the bending moment, shear force, and axial force which act on a steel pillar.

  According to a third aspect of the present invention, studs (for example, studs 23 and 33 described later) are provided on the outer peripheral surface of the lower end portion of the steel column and / or the outer peripheral surface of the connecting member, and the stud is made of the steel. It is embedded in the concrete body (for example, below-mentioned foundation footing 40) which covers the outer peripheral surface of the lower end part of a pillar.

  According to the third invention, since the stud is provided on the outer peripheral surface of the lower end portion of the steel column and / or the outer peripheral surface of the connecting member, the connecting member is fixed to a concrete body such as a foundation footing via the stud, The connecting member can be firmly fixed to the basic footing.

  According to the present invention, the concrete body covering the outer peripheral surface of the lower end portion of the steel column has a lower end surface located below the upper end surface of the pile, and the upper end surface is higher than the lower end surface of the steel column. It is preferable that it is located in.

  According to the present invention, it is easy to position the steel column erection position, and the steel column and the pile have excellent toughness by smoothly transmitting the force generated in the superstructure to the pile. Can provide the structure.

It is a longitudinal cross-sectional view of the junction part structure of the pillar and pile which concern on 1st Embodiment of this invention. It is AA sectional drawing and BB sectional drawing of FIG. It is a longitudinal cross-sectional view of the junction part structure of the pillar and pile which concern on 2nd Embodiment of this invention. It is CC sectional drawing and DD sectional drawing of FIG. It is a longitudinal cross-sectional view of the junction part structure of the pillar and pile which concern on 3rd Embodiment of this invention. It is EE sectional drawing of FIG. It is a longitudinal cross-sectional view of the junction part structure of the pillar and pile which concerns on the 1st modification of this invention. It is the longitudinal cross-sectional view and FF cross-sectional view of the junction part structure of the pillar and pile which concern on the 2nd modification of this invention. It is the longitudinal cross-sectional view and GG sectional drawing of the junction part structure of the pillar and pile which concern on the 2nd modification of this invention.

The present inventor inserts a connecting member joined to the lower end of the steel column into the hollow portion of the pile head as a joint structure for connecting the steel column and the pile body, and solidifies the connecting member with concrete. Therefore, focusing on the fact that the connecting member functions as a height adjusting member for the steel pillar and also functions as a pulling resistance member for connecting the steel pillar and the pile body, the joint structure of the steel pillar and the pile body is It came to invent.
Specifically, the connecting member that connects the steel pillar and the pile is divided into an H-shaped steel material (first embodiment) joined to the lower end of the steel pillar and studs planted, and the steel pillar. It is the structure (3rd Embodiment) provided with the plate fixed to the several groove type steel materials joined to the pillar lower part (2nd Embodiment) and the pile upper end surface.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same constituent elements are denoted by the same reference numerals, and the description thereof is omitted or simplified.
[First Embodiment]
Drawing 1 is a longitudinal section of joined part structure 1 of a pillar and a pile concerning a 1st embodiment of the present invention. 2A is a cross-sectional view taken along the line AA in FIG. 1, and FIG. 2B is a cross-sectional view taken along the line BB in FIG.
The pillar-to-pile joint structure 1 includes a pile 10 constructed in the ground, a steel pillar 20, and a steel connecting member joined to the lower end of the steel pillar 20 and fixed to the pile 10. 30.
A foundation footing 40 into which the lower end of the steel pillar 20 and the connecting member 30 are driven is constructed at the top of the pile 10.

  The pile 10 is a ready-made cylindrical RC pile (centrifugal reinforced concrete pile), and is a hollow pile in which a hollow portion 11 is formed.

  The steel column 20 includes a column main body 21 made of H-shaped steel, a lower plate 22 provided at the lower end of the column main body 21, and a stud 23 planted on the outer peripheral surface of the lower end portion of the column main body 21. Prepare.

The connecting member 30 includes a vertical portion 31 made of an H-shaped steel extending substantially vertically, and a substantially horizontal plate-like upper plate 32 provided at the upper end of the vertical portion 31.
The lower plate 22 of the steel column 20 is joined to the upper plate 32 with bolts 24. Thereby, the upper plate 32 of the connection member 30 is joined to the lower plate 22 at the lower end of the steel column 20.

The lower end portion of the vertical portion 31 is inserted into the hollow portion 11 of the pile 10, and filled concrete is placed on the upper end portion of the hollow portion 11. Thereby, the lower end portion of the connecting member 30 is embedded in the hardened concrete body 12 of the hollow portion 11.
A stud 33 is planted on the upper flange of the vertical portion 31 and the outer peripheral surface of the web. However, when the external load borne by the steel column is small, a stud may be provided only on one of the flange and the web of the vertical portion.

  The vertical section 31 has a smaller horizontal cross-sectional area than the column main body 21 of the steel column 20. In addition, this vertical part 31 should just be the size which can ensure the fixation intensity | strength with respect to the pile 10 of the vertical part 31, and can fully resist the tensile force between the pile 10 and the steel pillars 20. FIG.

The portion of the column main body 21 provided with the stud 23 and the portion of the vertical portion 31 provided with the stud 33 are embedded in the foundation footing 40.
That is, the foundation footing 40 is a concrete body that covers the lower end portion of the steel column 20 and the outer peripheral surface of the connecting member 30, the lower end surface is located below the upper end surface of the pile 10, and the upper end surface is a steel column. It is located above the lower end surface of 20.

According to this embodiment, there are the following effects.
(1) The connecting member 30 joined to the steel column 20 and fixed to the pile 10 is provided. Therefore, the height position of the steel column 20 can be adjusted by adjusting the buried length of the connecting member 30. Further, since the connecting member 30 is joined to the steel column 20 and is fixed to the pile 10, the tensile force generated in the connecting member 30 is transmitted to the vertical reinforcing bars constituting the pile 10. The seismic performance of 20 can be secured sufficiently. Therefore, the foundation footing 40 can be reduced in size, the positioning of the steel column 20 can be easily positioned, and the force generated in the upper structure can be smoothly transmitted to the pile 10 to exhibit excellent toughness. it can.

  (2) Since the studs 23 and 33 are implanted on the outer peripheral surface of the lower end portion of the steel column 20 and the outer peripheral surface of the vertical portion 31 of the connecting member 30, the steel column 20 and the connecting member 30 are connected to the studs 23 and 33. It is firmly fixed to the concrete body of the foundation footing 40 via.

  (3) By joining the steel pillar 20 and the connecting member 30 via the upper plate 32, even if the steel pillar 20 and the vertical part 31 of the connecting member 30 have different cross-sectional shapes, they can be reliably joined. . Moreover, the vertical precision of the steel pillar 20 is securable by joining the steel pillar 20 to the substantially horizontal upper plate 32.

  (4) Since the lower end portion of the connecting member 30 is driven into the concrete body 12 filled in the cylindrical RC pile 10, the concrete body 12 is locked by the wall surface of the pile 10, and the friction caused by the concrete and the concrete body Since it is restrained by the adhesion action of 12, it is firmly joined to the pile 10.

[Second Embodiment]
FIG. 3 is a longitudinal cross-sectional view of a pillar-to-pile joint structure 1A according to the second embodiment of the present invention. 4A is a cross-sectional view taken along the line CC in FIG. 3, and FIG. 4B is a cross-sectional view taken along the line DD in FIG.
In the present embodiment, the steel pillar 20 </ b> A is divided into two parts in the vertical direction, and includes a pillar lower part 50 and a pillar upper part 51 provided on the pillar lower part 50.

The column lower part 50 includes a column main body 52 that is a square steel pipe, a lower plate 53 provided at the lower end of the column main body 52, an upper plate 54 that is a plate material provided at the upper end of the column main body 52, and the column main body 52. A stud 55 planted on the outer peripheral side surface.
The lower plate 53 of the column lower part 50 is joined to the upper plate 32 of the connecting member 30 with bolts 24.

  The column upper portion 51 includes a column main body 56 that is a square steel pipe, and a lower plate 57 provided at the lower end of the column main body 56. The lower plate 57 of the column upper portion 51 is bolted to the upper plate 54 of the column lower portion 50.

  Further, the vertical portion 31 of the connecting member 30A is configured by arranging a pair of channel steels back to back and at a predetermined interval.

According to this embodiment, in addition to the effects (1) to (4) described above, the following effects can be obtained.
(5) Since the steel column 20A is divided into two parts in the vertical direction, the vertical accuracy can be easily managed when the steel column 20A is built in the pile 10.

[Third Embodiment]
FIG. 5 is a longitudinal cross-sectional view of a pillar-to-pile joint structure 1B according to a third embodiment of the present invention. 6 is a cross-sectional view taken along line EE in FIG.
In the present embodiment, the fixing member 60 is attached to the connecting member 30B. The fixing member 60 includes an annular plate 61 fixed to the upper end surface of the pile 10, and a fixing portion 62 extending downward from the plate 61 and embedded in the concrete body 12 of the pile 10.
A disk-shaped lower plate 34 is attached to the lower end portion of the vertical portion 31 of the connecting member 30B. The lower plate 34 is joined to the plate 61 of the fixing member 60 with bolts 63.

  According to this embodiment, there are the same effects as the above-mentioned (1) to (4).

It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.
For example, in each above-mentioned embodiment, although the ready-made RC pile was used as the pile 10, it is not restricted to this, For example, PC pile (prestressed concrete pile), PHC pile (high-strength prestressed concrete pile), PRC pile ( High strength prestressed reinforced concrete piles) and SC piles (concrete piles with shell steel pipes) may be used.

  Further, in each of the above-described embodiments, the column main body 21 of the steel column 20 is H-shaped steel, and the column main bodies 52 and 56 of the steel column 20A are rectangular steel pipes. May be. Furthermore, concrete may be filled in a column body that is a square steel tube or a circular steel tube, and the steel column may be a CFT (Concrete Filled Steel Tube) column.

  The pile of the present invention may be a cast-in-place concrete pile constructed at a construction site, not a ready-made concrete pile. In the case of a cast-in-place concrete pile, a hollow portion is often not provided in the pile head, and the steel pillar and the pile can be connected with the connecting material by driving the connecting material near the center of the pile body.

  Further, in each of the above-described embodiments, the lower plate 22 of the steel column 20 and the upper plate 32 of the connecting member 30 are connected, but not limited to this, the lower portion of the steel column 20 is connected to the upper end portion of the connecting member 30. A pair of angle steel materials may be attached to the lower surface of the plate 22 and the angle steel materials and the lower plate 22 of the steel column 20 may be connected. The angle steel is a connecting member between the steel column 20 and the connecting member 30 and also serves as a height adjusting member.

  Further, as shown in FIG. 7, studs 33 may be planted on the flanges and the outer peripheral surfaces of the webs of the vertical portion 31 of the connecting member 30 embedded in the concrete body 12. According to this configuration, the vertical portion 31 of the connecting member 30 including the stud 33 is firmly joined to the pile 10 due to an adhesion action with the concrete body 12 of the hollow portion 11 of the pile 10. Further, the bending moment, shearing force and axial force transmitted from the vertical portion 31 of the connecting member 30 to the concrete body 12 are applied to the pile 10 by a frictional resistance mechanism between the concrete body 12 of the pile 10 and the inner peripheral surface of the pile 10. Communicated. Therefore, the concrete body 12 of the pile 10 has a height sufficient to transmit the internal stress component to the pile 10 by frictional resistance.

  In addition, as shown in FIG. 8, by attaching a positioning member 35 extending in the horizontal direction to a predetermined height position of the lower portion of the connecting member 30 and placing the positioning member 35 on the upper end edge of the pile 10, The connecting member 30 may be positioned in the height direction. The positioning member 35 is, for example, an angle steel material or a groove steel material, and is fixed to the connecting member 30 by welding or bolts. According to this structure, the building accuracy in the height direction of the steel pillar 20 and the fixing degree at the time of building can be improved.

  Further, as shown in FIG. 9, a positioning member 36 extending in the horizontal direction is attached to a predetermined height position below the connecting member 30, and the positioning member 36 is connected to the concrete body 12 by placing it on the upper surface. The member 30 may be positioned in the height direction. The positioning member 36 is, for example, a flat steel material, an angle steel material, or a groove steel material. According to this structure, the building accuracy in the height direction of the steel pillar 20 and the fixing degree at the time of building can be improved.

DESCRIPTION OF SYMBOLS 1, 1A, 1B ... Joint part structure of pillar and pile 10 ... Pile 11 ... Hollow part 12 ... Concrete body 20, 20A ... Steel pillar 21 ... Column main body 22 ... Lower plate 23 ... Stud 24 ... Bolt 30, 30A, 30B: Connecting member 31: Vertical portion 32 ... Upper plate 33 ... Stud 34 ... Lower plate 35, 36 ... Positioning member 40 ... Base footing 50 ... Column lower portion 51 ... Column upper portion 52 ... Column main body 53 ... Lower plate 54 ... Upper plate 55 ... Stud 56 ... Pillar body 57 ... Lower plate 60 ... Fixing member 61 ... Plate 62 ... Fixing part 63 ... Bolt

Claims (3)

It is the structure of the joint between steel columns and piles,
A steel connecting member having a plate at the upper end is provided,
The plate of the connecting member is joined to the lower end of the steel column,
The steel pillar-pile joint structure, wherein the lower end of the connecting member is embedded in a concrete body inside the pile.   The steel pillar and pile joint structure according to claim 1, wherein a stud is provided on an outer peripheral surface of a portion of the connecting member embedded in the concrete body. Studs are provided on the outer peripheral surface of the lower end of the steel column and / or the outer peripheral surface of the connecting member,
The steel pillar-pile joint structure according to claim 1 or 2, wherein the stud is embedded in a concrete body that covers an outer peripheral surface of a lower end portion of the steel pillar.

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