JP2020100978A - Joint structure of pillar and foundation - Google Patents

Abstract

To provide a joint structure of a pillar and a foundation that can minimize an end free space between an anchor bolt and an end of the foundation while the anchor bolt resists both a shearing force caused by a horizontal force and a pulling force caused by a pulling force during an earthquake.SOLUTION: In a joint structure 100 of a pillar and a foundation, a pillar 10 having one end 42 of a brace 40 attached to a pillar base and a concrete foundation 60 are joined. At a top end 61 of the foundation 60, a first anchor bolt 81 on an end portion 62 side of the foundation 60 and directly below the pillar 10 and a second anchor bolt 85 on the brace 40 side are arranged. A first anchor hole 71 and a second anchor hole 72 are formed in a base plate 70 to which the pillar base is joined. A second clearance G2 between the second anchor bolt 85 and the second anchor hole 72 is smaller than a first clearance G1 between the first anchor bolt 81 and the first anchor hole 71.SELECTED DRAWING: Figure 2

Description

The present invention relates to a joint structure of a column and a foundation.

In a building such as a steel-framed house, a base plate joined to the lower end of a steel column is fixed to a foundation such as a concrete cloth foundation via anchor bolts. The wall of the building forms a frame structure by a plurality of columns and beams, and a bearing wall is formed by incorporating braces or the like into the frame structure. The building is designed to ensure a certain level of earthquake resistance by arranging various load bearing walls in a well-balanced manner.

In the bearing walls at the corners and corners of the building, the lower end of the brace is often attached to the column base of the column arranged close to the end of the foundation. For example, regarding a load-bearing wall formed by two columns and a beam that joins the upper ends of at least two columns, to the column base of one of these two columns and the column head of the other column, Bearing walls in the form of braces mounted over them are generally applied.

In the load bearing wall of this form, the lower end of the brace may be attached to the column base of the column close to the end of the foundation as described above, depending on the positional relationship of the outlet or the like. Alternatively, for example, in a sleeve wall having the above-mentioned brace with a width of 1P (for example, 910 mm width), the sleeve wall can be constructed on a foundation corresponding to the width of the sleeve wall. Even in such a sleeve wall, since the lower end of the brace is attached to the column base of one of the two columns, the column to which the lower end of the brace is attached is Will be disposed close to the end of the.

As described above, various problems may occur when the lower end of the brace is attached to the column base of the column arranged near the end of the foundation. First, when the horizontal force at the time of an earthquake acts on the bearing wall, this horizontal force is transmitted to the foundation through the anchor bolts that connect the two columns forming the bearing wall and the foundation. If the space between the anchor bolt and the end of the foundation is too small, the shear force resulting from the horizontal force transmitted from the anchor bolt may cause the fracture crack of the concrete at the end of the foundation. It is necessary to secure enough.

However, ensuring a sufficient open end dimension leads to increasing the distance from the anchor bolt on the end side of the foundation to the end of the foundation and increasing the plane dimension of the foundation. For this reason, it is desirable to reduce the distance from the anchor bolt to the open end of the space as much as possible while preventing the foundation from being damaged by the shearing force caused by the horizontal force during an earthquake.

In addition, not only the shearing force due to the horizontal force at the time of the above-mentioned earthquake but also the pulling force due to the pulling force acting from the column Since forces can also be generated, the design needs to be made to withstand these multiple external forces.

Therefore, for example, by connecting the column bases of the two columns that make up the load bearing wall, there is also a measure to reduce the shear force due to the horizontal force at the time of the earthquake that the anchor bolts of the columns on the end side of the foundation bear. is there. However, if a structure in which the column bases of two columns are connected to each other is adopted, it may affect the accommodation of large hauls, joists, etc. arranged on the foundation, and the placement of the wall base material may be forced to be changed. This is not preferable because it affects the arrangement of other members.

Here, a building foundation structure including a reinforcing metal member that comes into contact with and engages with an anchor bolt of the building foundation has been proposed. Specifically, this reinforcing metal is anchored to a contact engagement portion that comes into contact with and engages with an anchor bolt of the building foundation, and anchors to concrete that is the building foundation at a position horizontally separated from the contact engagement portion. The bolt includes a fixing portion that becomes a resistance when a shearing force is applied to the bolt, and a connecting portion that connects the fixing portion to the contact engagement portion. The reinforcing hardware is provided on an anchor bolt provided at the end of the building foundation such that the fixing portion is located opposite to the empty side of the building foundation (see, for example, Patent Document 1).

JP, 2016-113876, A

According to the building foundation structure described in Patent Document 1, it is possible to prevent split fracture of concrete as a foundation even when the end space between the anchor bolt and the foundation is small. By the way, although it is not clear from the description of Patent Document 1, the anchor bolt provided with the reinforcing metal member described in Patent Document 1 is applied to the joint structure of the column and the base in which the lower end of the brace is attached to the column base. In this case, as described above, it is necessary to resist not only the shearing force caused by the horizontal force at the time of the earthquake but also the tensile force caused by the pulling force from the column. However, in Patent Document 1, only the shearing force is taken up as an external force to be opposed, and while the anchor bolt resists both the shearing force due to the horizontal force at the time of an earthquake and the tensile force due to the pulling out force, the anchor bolt There is no description about the structure for reducing the clearance between the bolt and the end of the foundation.

The present invention has been made in view of the above problems, and while the anchor bolt resists both the shearing force due to the horizontal force and the pulling force due to the pulling force during an earthquake, the end portion of the anchor bolt and the foundation The purpose is to provide a joint structure of columns and foundations that can minimize the end space of the columns.

In order to achieve the above object, one aspect of the joint structure of a pillar and a foundation according to the present invention is
A joint structure of a pillar and a foundation, in which a pillar in which one end of a brace is attached to a pillar base is joined to a concrete foundation,
The top end of the foundation is provided with a first anchor bolt on the end side of the foundation and directly below the pillar, and a second anchor bolt on the brace side of the first anchor bolt. Is
A base plate in which the column base is joined to the top end of the foundation is arranged,
The base plate is provided with a first anchor hole through which the first anchor bolt is inserted, and a second anchor hole through which the second anchor bolt is inserted,
The base plate is joined to the foundation by the first anchor bolt and the second anchor bolt,
The second clearance between the second anchor bolt and the second anchor hole is smaller than the first clearance between the first anchor bolt and the first anchor hole.

According to this aspect, the second anchor bolt and the second anchor relatively on the brace side (inner side) than the first clearance between the first anchor bolt on the end side of the foundation and the first anchor hole of the base plate. Since the second clearance with the hole is small, the shearing force caused by the horizontal force at the time of the earthquake first acts on the second anchor bolt, so that all or most of the shearing force should be borne by the second anchor bolt. You can Since the first anchor bolt on the end side of the foundation is directly below the column, the tensile force due to the pulling-out force of the column first acts on the first anchor bolt, and all or most of the tensile force is applied to the first anchor bolt. One anchor bolt can bear. In this way, by changing the clearance between the anchor hole formed in the base plate and the anchor bolt between the anchor bolt directly under the pillar and the anchor bolt inside the pillar, the shear force acting through the pillar can be reduced. It is possible to separate the anchor bolts that bear the tensile force. Since the first anchor bolt near the end of the foundation does not mainly bear the shearing force, the risk of splitting fracture of the foundation end due to the shearing force is reduced, which reduces the end of the first anchor bolt and the foundation. The edge space of can be made as small as possible.

The joint structure of the present aspect is a joint structure of an end portion of a concrete foundation and a column fixed to the foundation by anchor bolts in the vicinity of the end portion, and has at least two anchor bolts. Here, the “edge” refers to the corner such as the corner of the corner of the building, the edge of the sleeve wall, or the intersection of the outer wall having a T-shaped plan view, and the foundation such as the cloth foundation faces the outside. It is a part. In the structure in which one end of the brace is attached to the column base of the column near the end of this foundation, when the horizontal horizontal force that acts on the load-bearing wall is alternated during the earthquake, there is a pulling force on the column. The pushing force acts alternately. When the pulling force acts, the inner shearing force toward the side opposite to the end (brace side) of the foundation acts, and when the pushing force acts, the outer shearing force acts toward the end side of the foundation. If the inner shear force acts, the split fracture at the end of the foundation is not a problem, but if the outer shear force acts, this split fracture can be a problem.

In the joint structure of the present aspect, the second anchor bolt located relatively far from the end of the foundation bears all or most of the shearing force, thereby suppressing the occurrence of splitting fracture at the end of the foundation. ing. If the first anchor bolt near the end of the foundation bears much of the shearing force, there is a risk of splitting and breaking the concrete at the end due to the reaction force from the first anchor bolt to which the shearing force is applied. is there.

Here, as the first anchor bolt and the second anchor bolt, anchor bolts having the same diameter may be applied, for example, a first anchor bolt having a relatively large diameter may be applied, and a shearing force acting Both anchor diameters are appropriately set by the tensile force. However, in the case of a load bearing wall with a width of about 1P, since the height is higher than the width of the load bearing wall, the pulling force due to the pulling force tends to be superior to the shearing force due to the horizontal force, In such a case, it is necessary to relatively increase the anchor diameter of the first anchor bolt that mainly bears the tensile force.

In addition, for example, by setting the second anchor bolt to have a relatively small diameter, the second anchor bolt having a relatively small diameter can be used when performing table repair work when the placement positions of the two anchor bolts are displaced from the design positions. By bending a part of the anchor bolt and adjusting the horizontal position, it is possible to easily perform the re-building work on site.

Further, another aspect of the joint structure of the pillar and the foundation according to the present invention is characterized in that the first anchor bolt is arranged on the pillar core of the pillar.

According to this aspect, since the first anchor bolt is arranged on the column core of the column, the tensile force acting from the column easily acts directly on the first anchor bolt, and the tensile force by the first anchor bolt is increased. And the burden of the shearing force by the second anchor bolt can be separated more clearly. Further, since the eccentric moment due to the pulling force hardly occurs in the base plate, the thickness of the base plate can be made as thin as possible.

Another aspect of the joint structure of a pillar and a foundation according to the present invention is that an elastic material is embedded in a range from a top end of the foundation to a predetermined depth around the first anchor bolt in the foundation. Characterize.

According to this aspect, even if a part of the shearing force acts on the first anchor bolt on the end side of the foundation, around the first anchor bolt in the foundation, a predetermined depth from the top end of the foundation is reached. By embedding the elastic material in the range up to, the first anchor bolt can absorb the shearing force while elastically or plastically deforming inside the deformable elastic material. Therefore, it is possible to prevent the reaction force of the first anchor bolt due to the shearing force from being applied to the foundation on the end side of the first anchor bolt, and to prevent the split end fracture of the foundation end caused by the reaction force. be able to. Further, since the elastic material is arranged around the first anchor bolt in the foundation from the top end of the foundation to a predetermined depth, it is possible to suppress the infiltration of water into the foundation. Examples of this elastic material include foamed resin and rubber having a relatively high expansion ratio.

As can be understood from the above description, according to the joint structure of the column and the foundation of the present invention, while the anchor bolt resists both the shearing force caused by the horizontal force at the time of the earthquake and the tensile force caused by the pulling force, The free space between the anchor bolt and the end of the foundation can be made as small as possible.

It is a front view of an example of a load bearing wall which has a joint structure of a pillar and a foundation concerning an embodiment. It is an enlarged view of the II section of FIG. 1, and is a longitudinal cross-sectional view of an example of the joint structure of the pillar and the foundation according to the first embodiment. It is a III-III arrow line view of FIG. It is a longitudinal cross-sectional view of an example of a joint structure of a pillar and a foundation according to the second embodiment.

Hereinafter, the joint structure of the pillar and the foundation according to each embodiment will be described with reference to the accompanying drawings. In the present specification and the drawings, substantially the same components may be denoted by the same reference numerals to omit redundant description.

[One Example of Bearing Wall and Joint Structure of Pillar and Foundation According to First Embodiment]
First, with reference to FIG. 1 to FIG. 3, an example of a load bearing wall and an example of a joint structure of a column and a foundation according to the first embodiment will be described. Here, FIG. 1 is a front view of an example of a bearing wall having a joint structure of a column and a foundation according to the embodiment. 2 is an enlarged view of a II portion of FIG. 1, which is a vertical cross-sectional view of an example of a joint structure of a pillar and a foundation according to the first embodiment, and FIG. 3 is a III-III portion of FIG. FIG.

The load bearing wall 50 includes a pair of pillars 10 and 20 which are erected at a distance from each other, a pair of beams 30 which are laid across the pair of pillars 10 and 20 at a distance, and an upper end of one pillar 20. And a brace 40 having both ends joined to the gusset plate 41 on the other side and the gusset plate 41 on the lower end of the other column 10. The columns 10 and 20 are fixed to the top end 61 of a concrete (reinforced concrete) foundation 60 by anchor bolts 81 and 85 via a base plate 70, respectively.

Further, in the load bearing wall 50 of the illustrated example, one pillar 10 is arranged in the vicinity of the end portion 62 of the foundation 60, and an end empty space C is provided between the anchor bolt 81 and the end portion 62 immediately below the pillar 10. .. Then, one end of the brace 40 is joined to the column base of the column 10 near the end 62, and the column 10 and the foundation 60 are joined together by the two anchor bolts 81 and 85 via the base plate 70. By doing so, the column-base joint structure 100 according to the embodiment is formed. Here, the end portion 62 of the foundation 60 is the corner portion of the projecting corner of the building, the end portion of the sleeve wall, the intersection of the T-shaped outer wall of the plan view, or the like, and the foundation 60 such as the cloth foundation is outside. It is the part that faces.

Although the details of the joint structure 100 will be described below, for example, in the pillar 10 in the vicinity of the end portion 62 of the foundation 60, one first anchor bolt 81 is arranged immediately below the pillar 10 and is located inside the pillar 10. The other second anchor bolt 85 is arranged on the (brace side), and the base plate 70 projects inward from the lower end of the column 10.

The width t1 of the load bearing wall 50 can be set to, for example, a normal 1P width (for example, 910 mm width). In addition, although the illustrated example shows only a part of the first floor portion having the construction surface on which the load bearing wall 50 is arranged, the building having the load bearing wall 50 is also applied to a building having two or more floors.

The columns 10 and 20 are formed of a shaped steel material such as a square steel pipe or an H-shaped steel, and the beam 30 is formed of a shaped steel material such as an H-shaped steel, which are bolted to each other (for example, fixed by a plurality of middle bolts) or welded. Are joined together. Further, the brace 40 is a brace capable of resisting a compressive force, and may be formed by a flat steel plate, a H-shaped steel, a chevron steel, a shaped steel material such as a grooved steel, a square steel pipe, or the like. It is made of steel plate. In the present specification, “welding” refers to groove welding (complete penetration welding, partial penetration welding), fillet welding, etc., depending on the strength and connection mode (rigid connection, pin connection) required for the connection portion. The appropriate welding selected by the following is shown.

At the time of an earthquake, the horizontal forces H1 and H2 are repeatedly applied to the structural surface including the bearing wall 50 in the horizontal direction. In the bearing wall 50 of the illustrated example, a pulling force P1 acts on the column 10 in the vicinity of the end 62 of the foundation 60 by the horizontal force H1 in the left direction of the paper, and at least the column 10 is pulled by this pulling force P1. A tensile force T1 acts on the first anchor bolt 81 located immediately below. At this time, a shearing force S1 in the inward direction of the load-bearing wall 50, which is in the same direction as the horizontal force H1, may act on the two anchor bolts 81 and 85.

On the other hand, the horizontal force H2 in the right direction of the paper causes a pushing force P2 to act on the column 10 near the end 62 of the foundation 60, and the pushing force P2 causes at least the first anchor bolt directly below the column 10. A compression force T2 acts on 81. Further, at this time, the two shear bolts 81 and 85 may be acted on by the outward shearing force S2 toward the end portion 62 side of the foundation 60 which is in the same direction as the horizontal force H2. When the shear force S2 in the outward direction is different from the shear force S1 in the inward direction and acts on the first anchor bolt 81 on the end 62 side among the two anchor bolts 81 and 85, when the end empty space C is small, For example, there is a risk of split fracture of the foundation 60 along the split fracture surface D starting from the top of the inner second anchor bolt 85.

As will be described below, the joining structure 100 according to the present embodiment is capable of reducing the open end C as much as possible while suppressing splitting fracture in the vicinity of the end portion 62 of the foundation 60. The structure. Next, the column-base joint structure 100 according to the first embodiment will be described in detail with reference to FIGS. 2 and 3.

As shown by the alternate long and short dash line in FIG. 3, a pedestal block having a U-shaped steel vertical member 15 in plan view and a steel pedestal plate 16 joined to the upper end of the steel vertical member 15 by welding. 17 is welded to the lower end of the pillar 10. By this pedestal block 17, the nut of the first anchor bolt 82 can be tightened inside.

A steel base plate 70 is welded to the lower end of the pedestal block 17. As shown in FIG. 2, the first anchor bolt 81 is arranged on the pillar core L1 of the pillar 10. In the illustrated example, the intersection of the pillar core L1 and the brace core L2 is the ceiling of the base plate 70 and the foundation 60. It intersects with the first anchor bolt 81 at the end interface.

A gusset plate 41 is welded to the inner surface of the column 10, and one end 42 of the brace 40 is bolted to the gusset plate 41.

A base plate 70 is welded to the lower end of the pedestal block 17 on the column base of the column 10. As shown in FIGS. 2 and 3, the base plate 70 has a first anchor hole 71 through which the first anchor bolt 81 is inserted and a second anchor hole 72 through which the second anchor bolt 85 is inserted. .. The second clearance G2 between the second anchor bolt 85 and the second anchor hole 72 is set to be smaller than the first clearance G1 between the first anchor bolt 81 and the first anchor hole 71. ..

As shown in FIG. 2, the base plate 70 is placed on the top end 61 of the foundation 60, and the first anchor bolt 81 is arranged inside the foundation 60 along the column core L1 of the column 10 through the first anchor hole 71. It is embedded in a predetermined embedding length. By attaching a washer 83 having a diameter larger than that of the first anchor hole 71 to the first anchor bolt 81 protruding upward from the top end 61 of the foundation 60 and tightening the tightening nut 82, the first anchor The bolt 81 is fixed to the base plate 70. Further, there is an empty end C between the first anchor bolt 81 and the end 62 of the foundation 60.

On the other hand, the second anchor bolt 85 is embedded in the base 60 by a predetermined embedding length on the brace side (inner side) of the column core L1 of the column 10 through the second anchor hole 72. A washer 87 having a diameter larger than that of the second anchor hole 72 is attached to the second anchor bolt 85 projecting upward from the top end 61 of the foundation 60, and the second anchor bolt 85 is tightened with the tightening nut 86, whereby the second anchor. The bolt 85 is fixed to the base plate 70. Although the joining structure 100 of the illustrated example has a form in which the base plate 70 is fixed to the foundation 60 by two anchor bolts 81 and 85, for example, four anchor bolts 81 and 85 are provided in total, that is, four bolts in total. The base plate 70 may be fixed to the base 60 by anchor bolts.

In this way, the pillar 10 continuous with the base plate 70 is joined to the foundation 60 by the two first anchor bolts 81 and the second anchor bolts 85.

In the joint structure 100, the second brace 40 side (inner side) is relatively located than the first clearance G1 between the first anchor bolt 81 on the end 62 side of the base 60 and the first anchor hole 71 of the base plate 70. Since the second clearance G2 between the anchor bolt 85 and the second anchor hole 72 is small, the shearing force S2 resulting from the horizontal force H2 at the time of the earthquake first acts on the second anchor bolt 85. Therefore, all or most of the shearing force S2 can be applied to the second anchor bolt 85 located far from the end portion 62 of the foundation 60.

Further, since the first anchor bolt 81 on the side of the end portion 62 of the foundation 60 is directly below the column 10, the tensile force T1 resulting from the pulling-out force P1 of the column 10 first acts on the first anchor bolt 81. Therefore, all or most of the tensile force T1 can be applied to the first anchor bolt 81.

In this way, the clearances G1 and G2 between the anchor holes 71 and 72 formed in the base plate 70 and the anchor bolts 81 and 85 are changed between the anchor bolt 81 directly below the pillar 10 and the anchor bolt 85 inside thereof. By doing so, it is possible to separate the anchor bolts that bear the shearing force S2 acting through the column 10 and the tensile force T1.

Since the first anchor bolt 81 near the end 62 of the foundation 60 does not mainly bear the shearing force S2, the risk of splitting fracture along the splitting fracture surface D at the end of the foundation 60 due to the shearing force S2 is reduced. be able to. This makes it possible to reduce the end clearance C between the first anchor bolt 81 and the end 62 of the foundation 60 as small as possible. As described above, according to the joint structure 100, the anchor bolts 81 and 85 resist both the shearing force S2 caused by the horizontal force H2 and the tensile force T1 caused by the pulling force P1 at the time of the earthquake, while the anchor bolts 81, It is possible to make the end clearance C of 85 and the end portion 62 of the foundation 60 as small as possible.

Actually, the first anchor bolt 81 does not bear the entire tensile force T1 and a part of the tensile force T1 is transmitted to the second anchor bolt 85 through the base plate 70, and the second anchor bolt 85 also has the tensile force T1. Can bear some. If reinforcing ribs (not shown) are attached to the pedestal block 17 and the base plate 70 overhanging from the pedestal block 17, the flexural rigidity of the base plate 70 is increased by the reinforcing ribs. More tensile force may act on the second anchor bolt 85 when T1 acts.

However, in the joint structure 100 of the illustrated example, since such a reinforcing rib is not applied, it is possible to mainly bear the tensile force T1 on the first anchor bolt 81. However, if it is desired to reduce the tensile force borne by the first anchor bolt 81 and reduce the anchor diameter, the thickness of the base plate 70 may be increased or the reinforcing ribs described above may be applied to reduce the tensile force T1. The second anchor bolt 85 may be made to bear a larger proportion.

Further, since the load bearing wall 50 having the joining structure 100 shown in the figure is a load bearing wall having a width of about 1P and its height is higher than the width of the load bearing wall 50, the pulling force is generally larger than the shearing force caused by the horizontal force. The tensile force due to the tendency to be superior. In such a case, the anchor diameter of the first anchor bolt 81, which mainly bears the tensile force, may be relatively increased. For example, M22 can be applied to the first anchor bolt 81 and M16 can be applied to the second anchor bolt 85. By setting the second anchor bolt 85 to have a relatively small diameter in this way, for example, when the mounting position of the two anchor bolts 81 and 85 is deviated from the design position, the relative work is performed during the realignment work. Further, it is possible to bend a part of the small-diameter second anchor bolt 85 and adjust the horizontal position thereof, which makes it possible to easily perform the re-building work on site.

When M22 is applied to the first anchor bolt 81 and M16 is applied to the second anchor bolt 85, the first anchor hole 71 of the base plate 70 has a diameter of 27 mm (the maximum value of the first clearance G1 is 5 mm). Can be set to about 18 mm (the maximum value of the second clearance G2 is 2 mm). At this time, the hole diameter of the anchor ruler for positioning the anchor is smaller than the difference 3 mm (5 mm-2 mm) between the maximum values of the first clearance G1 and the second clearance G2 of the base plate 70, for example, about 0.5 mm. It is better to set to.

[Joint structure of pillar and foundation according to the second embodiment]
Next, with reference to FIG. 4, an example of the joint structure of the pillar and the foundation according to the second embodiment will be described. Here, FIG. 4 is a vertical cross-sectional view of an example of a joint structure of a pillar and a foundation according to the second embodiment.

In the illustrated joint structure 100A, a counterbore 63 is provided in a range from the top end of the base 60 to a predetermined depth t2 around the first anchor bolt 81 in the base 60, and the elastic member 90 is provided in the counterbore 63. It is buried.

Here, the elastic material 90 is formed of, for example, a foaming resin or rubber having a relatively high firing rate. Further, the predetermined depth t2 is set to, for example, about 50 mm to 150 mm from the top end 61 of the foundation 60.

When a part of the shearing force due to the horizontal force at the time of the earthquake acts on the first anchor bolt 81 and the end free space C is small, there is a risk of splitting breakage of the foundation end. On the other hand, in the joint structure 100A, the elastic material 90 is embedded in the range from the top end 61 of the base 60 to the predetermined depth t2 around the first anchor bolt 81 in the base 60, so that the elastic deformability is increased. Inside the material 90, the first anchor bolt 81 can absorb the shearing force while being elastically or plastically deformed. Therefore, it is suppressed that a reaction force of the first anchor bolt 81 due to a shearing force is applied to the foundation on the end side of the first anchor bolt 81, and the splitting fracture of the foundation end portion due to this reaction force is suppressed. can do.

There may be other embodiments in which other components are combined with the configurations and the like described in the above embodiments, and the present invention is not limited to the configurations shown here. This point can be changed without departing from the spirit of the present invention, and can be appropriately determined according to the application form.

10, 20: Pillar, 30: Beam, 40: Brace, 41: Gusset plate, 50: Bearing wall, 60: Foundation, 61: Top end (base top end), 62: End part, 70: Base plate, 71: No. One anchor hole (anchor hole), 72: second anchor hole (anchor hole), 81: first anchor bolt (anchor bolt), 82: nut, 83: washer, 85: second anchor bolt (anchor bolt), 86 : Nut, 87: Washer, 90: Elastic material, 100, 100A: Joint structure (joint structure of column and foundation), G1: First clearance, G2: Second clearance, C: End free space, H1, H2: Horizontal force , P1: pull-out force, P2: push-in force, T1: tensile force, T2: compressive force, S1, S2: shear force, D: split fracture surface

Claims (3)

A joint structure of a pillar and a foundation, in which a pillar in which one end of a brace is attached to a pillar base is joined to a concrete foundation,
The top end of the foundation is provided with a first anchor bolt on the end side of the foundation and directly below the pillar, and a second anchor bolt on the brace side of the first anchor bolt. Is
A base plate in which the column base is joined to the top end of the foundation is arranged,
The base plate is provided with a first anchor hole through which the first anchor bolt is inserted, and a second anchor hole through which the second anchor bolt is inserted,
The base plate is joined to the foundation by the first anchor bolt and the second anchor bolt,
A column-foundation joint structure, wherein a second clearance between the second anchor bolt and the second anchor hole is smaller than a first clearance between the first anchor bolt and the first anchor hole. The joint structure of a pillar and a foundation according to claim 1, wherein the first anchor bolt is arranged on a pillar core of the pillar. The pillar and the foundation according to claim 1 or 2, wherein an elastic material is embedded in a range from a top end of the foundation to a predetermined depth around the first anchor bolt in the foundation. Construction.

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