JP5198668B1 - Column base joints and building structures - Google Patents

Abstract

An object of the present invention is to provide a column base joint bracket having improved deformability without greatly affecting the strength of the column base joint bracket, and a building structure that supports the column using such a column base joint bracket. To provide.
In a column base joint that is installed on a building foundation and supports the lower end of a column, a receiving plate and a base plate 4 that are spaced apart from each other vertically, a receiving plate 3 and A rectangular box portion 1 constructed by leg plates 5 arranged opposite to both ends of the base plate 4 and an upper position of the box portion 1 and formed between the leg plates 5 of the receiving plate 3. A notch-like recess 13 opened on the lower edge side was formed in the insertion plate 2 so as to be provided with the insertion plate 2 whose lower side was inserted and fixed with respect to the slit 10.
[Selection] Figure 1

Description

  The present invention relates to a column base joint for supporting a column on a foundation and a building structure that supports the column using such a column base joint.

  Conventionally, in order to support a column on a foundation, for example, a column base joint fitting as shown in Patent Document 1 has been proposed. The column base joint fitting in this patent document has a box portion constructed by a receiving plate 3 and a substrate 1 arranged above and below, and a leg plate 2 arranged oppositely between the receiving plate 3 and the substrate 1, and on the box portion. The connecting plate 4 is erected. As shown in FIG. 4, the base plate 1 is fixed to the foundation-side anchor bolt 61 by the nut 62, and the column is formed on the lower end side of the column base joint fitting fixed on the foundation in this way. The connecting plate 4 is installed on the receiving plate 3 so that the connecting plate 4 is inserted into the slit 51, and the connecting rod 43 is driven and joined from the lateral direction.

JP 2011-58235 A

When a column is installed on a column base attached directly to such a foundation, if an external force (specifically, for example, an earthquake or a typhoon) acts on the building, a pulling force (tensile force) is applied to this joint. Works. Considering the case where a large external force is applied due to an extremely rare earthquake or typhoon, it is necessary to improve the deformation capacity (energy absorption capacity) of the column base joint.
Therefore, it is conceivable to use a softer steel material or to reduce the thickness of the material so that it can be easily deformed when a pulling force is applied to the column. However, it is not preferable to greatly influence the strength of the column base joint fitting. Therefore, there has been a demand for means for improving the deformability without greatly affecting the strength of the column base joint fitting.
The present invention has been made in order to solve the above-mentioned problems, and the object thereof is to provide a column base joint fitting with improved deformability without greatly affecting the strength of the column base joint fitting, and the like. An object of the present invention is to provide a building structure that supports columns by using column-base joints.

In order to achieve the above object, in the invention according to claim 1, in the column base joint fitting which is installed on the building foundation and supports the lower end of the column, a receiving plate which is arranged at intervals in the vertical direction. A rectangular box portion constructed by a base plate and a leg member disposed opposite to both ends of the receiving plate and the base plate and rigidly joined to the receiving plate and the base plate, respectively. A column support plate which is erected at an upper position and is fixed by inserting a lower side of the slit formed between the leg members of the backing plate, and the box portion is closer to the center of the base plate mounting holes are formed in, while being secured to the anchor member of the basic side through the same mounting hole, the notch-like recess which is open on the lower edge side is formed in the pillar support plate, the notch-like recess It opens at a lower position than the backing plate, and its gist that the innermost part of the cutout-like recesses are extends upward position than the backing plate.
In addition, the gist of the invention of claim 2 is that, in addition to the configuration of the invention of claim 1, the leg members facing each other in the box portion are installed on the base plate and rigidly joined.
In addition to the configuration of the invention of claim 1 or 2, the gist of the invention of claim 3 is that the receiving plate is placed on the leg member facing and rigidly joined in the box portion. To do.
In addition, in the invention according to claim 4, in addition to the structure of any one of claims 1 to 3, both end edges into which the column support plate is inserted are rigidly joined to the inner surface of the leg member. Is the gist.
Further, the gist of the invention according to claim 5 is that the building structure is configured to support the column by using the column base joint metal fitting according to any one of claims 1 to 4.

In the above configuration, the column is erected on the column base joint fitting installed on the foundation, and the column is supported and fixed by the column support plate. When an upward pulling force (tensile load) is applied to the column, the column support plate is pulled upward as the column moves upward. At this time, since the receiving plate is joined to the leg members on both sides, the receiving plate is deformed so that the central portion is lifted. The column supporting plate is compressed in the width direction with the deformation. However, in the present invention, the column supporting plate is formed with a notch-shaped recess opened on the lower edge side. It is easy to be compressed. That is, the yield strength of the column support plate against the compressive load is reduced as compared with the conventional case. Therefore, the receiving plate is bent near the center with respect to the upward pulling load and allows the column supporting plate to move upward.
Also, since the tensile load also acts on the base plate via the leg member, if the base plate is fixed to the foundation inside the leg member, the outer side of the base plate can be lifted via the leg member. Deform. If this deformation is large, the tolerance of deformation of the entire leg joint fitting is improved.
With such a configuration, when a large upward pulling force is applied to the column, the stress can be distributed to other than the junction between the column and the column base joint.

The leg members facing each other in the box portion are preferably installed on the base plate and are rigidly joined in view of the strength of the column base joint fitting. Similarly, in the box portion, the receiving plate is preferably placed on the opposing leg member and rigidly joined, and both end edges of the column supporting plate inserted are rigidly joined to the inner surface of the leg member. preferable.
Here, the “notch-shaped recess” refers to the notch-shaped recess when the column-supporting plate is compressed in the left-right direction by making the lower side of the column-supporting plate notched and opening on the lower edge side. It is a dent that can be deformed so that opposing edge portions approach each other due to its compressive force, as if it were a dent formed in a bay shape that faces the sea. It is preferable that the depth direction is longer than the width direction. The notch-shaped recess may be formed by actually notching or may be formed by pressing into such a shape from the beginning without actually notching.
Moreover, the leg member arrange | positioned facing is not necessarily a left-right pair, and the leg member may be comprised by several parts. The shape of the notch-shaped recess is not particularly limited as long as it is a shape opened to the lower edge side. The notch-shaped recess is preferably formed at the center position in the width direction of the column support plate or at a position closer to the center, but is not necessarily formed at the center position in the width direction. May be. Further, there may be a plurality of notches.
As the column support plate, an insertion plate inserted into the slit formed at the lower end of the column side is assumed, but in addition to that, a column support that makes contact with the outer periphery of the column or holds the column between two plates It may be a plate for use.

  According to the invention described in each of the above claims, since the notch-shaped recess opened on the lower edge side is formed in the column support plate, the receiving plate supporting the column support plate is easily deformed. It is possible to provide a column base joint fitting in which the column support plate is easily pulled upward as the column moves upward, and energy can be absorbed with respect to a tensile load.

The front view of the joining fitting for column bases of embodiment of this invention. Sectional drawing in the AA in FIG. (A) is a top view of the column base joining metal fitting of the same embodiment, (b) is sectional drawing in the BB line in FIG. Explanatory drawing of the state which installed the column-base joining metal fitting of the same embodiment on the foundation, and made it stand upright on it. Explanatory drawing explaining the deformation | transformation image of the column base joining metal fitting when the upward pulling force acts in the state of FIG. Explanatory drawing explanatory drawing explaining the method to adjust the shift | offset | difference of the anchor bolt position at the time of installing the column-base joining metal fitting on a foundation. (A) is a bottom view of a washer, (b) is a side view of the same washer. Explanatory drawing explaining the method to join a column with respect to the column-base joining bracket installed on the foundation. The front view of the insertion board used for the same embodiment. The top view of the box part used for the same embodiment.

Hereinafter, a column base joint metal fitting according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1 to FIG. 3, the column base fitting is composed of an alloy box portion 1 and an alloy insertion plate 2 as a column support plate erected on the box portion 1.
The box part 1 is between the receiving plate 3 and the base plate 4 and the receiving plate 3 and the base plate 4 which are arranged at intervals in the vertical direction, and the left and right leg plates which are arranged on the outer sides of the receiving plate 3 and the base plate 4. 5 is formed in a substantially cubic box shape in which a passage is formed in the front-rear direction. The leg plate 5 is rigidly joined to the receiving plate 3 and the base plate 4 by welding. In the present embodiment, the overall height of the box portion 1 is 105.0 mm.
As shown in FIG. 3, the receiving plate 3 and the base plate 4 are plate bodies whose front, rear, left and right corners coincide with each other in plan view, and the base plate 4 is thicker than the thickness of the receiving plate 3 (in the present embodiment). The base plate 4 is doubled with respect to the thickness of the receiving plate 3 of 4.5 mm (9.0 mm). As shown in FIG. 3A, the receiving plate 3 and the base plate 4 have a square planar shape with a side of 119.0 mm. The leg plate 5 is a mirror-symmetric plate body that is curved so as to be concave outward so as to match the curved shape in the left-right direction of the receiving plate 3 in plan view. The thickness of the leg plate 5 in the present embodiment is 6.0 mm.

As shown in FIGS. 2 and 3, a circular through-hole 7 is formed at the center of the base plate 4 so as to communicate with the upper and lower sides. The inner diameter of the through hole 7 is 40 mm in the present embodiment. A first anti-slip portion 8 having a knurled mesh is formed on the periphery of the through hole 7 on the upper surface of the base plate 4. Around the first anti-slip portion 8, four cylindrical positioning pins 9 are erected at predetermined intervals. The positioning pin 9 is disposed at a position where the diagonal line of the base plate 4 and the first anti-slip portion 8 just intersect. As shown in FIGS. 1 and 6, a center mark 6 is engraved at the front center position and the back center position of the base plate 4 so as to be collated with the center (core) position of the foundation described above in the vertical direction. .
The receiving plate 3 is formed with slits 10 parallel to the front and rear sides of the receiving plate 3. As shown in FIG. 10, the slit 10 is linearly formed between the inner side walls of the leg plate 5 at the narrowest position of the receiving plate 3 in the left-right direction, that is, at the center position in the front-rear direction of the receiving plate 3. In the present embodiment, the length of the slit 10 in the left-right direction is 76.0 mm, and the width is 6.0 mm.

As shown in FIG. 9, the insertion plate 2 is a battledore-shaped plate body that is slightly tapered toward the lower side as a whole. Right and left sides near the lower edge are formed with cutout corner portions 14 having a right angle. The corner portion 14 includes a horizontal contact edge 14a and a vertical contact edge 14b. The insertion plate 2 has a vertical length of 214.5 mm, an upper edge side lateral width of 108.0 mm, a lower edge lateral width (between the vertical contact edges 14b) of 76.0 mm, and a thickness of 6.0 mm. The insertion plate 2 is inserted into the slit 10 of the receiving plate 3 from above and placed on the receiving plate 3 by the left and right horizontal contact edges 14a. As a result, the amount of advancement in the vertical direction across the receiving plate 3 of the insertion plate 2 is accurately determined. Further, the compressive load from the insertion plate 2 is transmitted in a well-balanced manner to the entire column base joint through the receiving plate 3. The vertical contact edge 14 b extending downward from the slit 10 is in contact with the inner wall of the leg plate 5. The insertion plate 2 is fixed by welding between the receiving plate 3 constituting the adjacent slit 10 and the leg plate 5. In the present embodiment, illustration of welding marks (beads) is omitted.
Five pin holes 11 are formed on the upper body side of the insertion plate 2. On the lower body side of the insertion plate 2, a notch-shaped recess 13 is formed at the center position in the left-right direction and opened to the lower edge side. The notch-like recess 13 is a recess having a smooth long shape with chamfered corners (that is, the depth is considerably longer than the width), and is located above the receiving plate 3 from the lower edge when the insertion plate 2 is fixed. It extends to the position. In the present embodiment, the notch-shaped recess 13 has a width of 14.0 mm and a length from the upper edge to the innermost part of 48.5 mm.

Next, a method of using the column base joint fitting configured as described above will be briefly described.
The column base joint fitting is placed so as to cover the anchor bolt 16 protruding on the foundation 15. At this time, the anchor bolt 16 projects into the box portion 1 from the through hole 7 formed in the base plate 4. Next, as shown in FIG. 4 and FIG. 6, the washer 18 is placed on the base plate 4 so as to be disposed inside the one positioning pin 9, and the anchor position is confirmed by the core mark 6 before anchoring. The nut 19 is fastened to the bolt 16 to complete the installation of the column base joint fitting on the foundation.
The washer 18 used here is a disk-shaped plate body having a circular outer shape in which an oval through-hole 20 is formed as shown in FIGS. 7 (a) and 7 (b). The through-hole 20 is arranged in an eccentric state so that the major axis direction is arranged from the center toward one direction of the outer periphery. As shown in FIG. 7A, a second anti-slip portion 24 that meshes with the first anti-slip portion 8 is formed on the bottom surface of the washer 18. By using such a washer 18, for example, as shown in FIG. 6, even if the anchor bolt 16 is slightly deviated from the position of the core of the foundation, the washer 18 is rotated according to the protruding direction of the anchor bolt 16. Thus, the column base joint fitting can always be accurately positioned at a position on the foundation, and the column base joint bracket can be fixed together with the washer 18 by the nut 19 at the exact position. Therefore, even if the protruding position of the anchor bolt 16 is slightly shifted on the foundation, it is possible to always install the column accurately.

Next, as shown in FIG. 8, the column 22 having the column connection slit 21 formed on the lower end surface is inserted into the column connection slit 21 so that the insertion plate 2 is inserted into the fixed column base joint. Place on the backing plate 3. Since the pillars 22 are formed with connecting holes 23 corresponding to the five pin holes 11 on the receiving plate 3 side, the corresponding connecting holes 11 and 23 are collated with each other by installing the pillar 22 on the receiving plate 3. A tunnel is formed in a direction orthogonal to the fiber direction of the column 22. Five drift pins 25 are driven into the tunnel from the side to complete the connection between the insertion plate 2 and the column 22.
When a large upward pulling force acts on a building structure in which the column 22 is fixed to the column base joint fitting installed on the foundation 15 as described above, the column base is pulled by the column and used for the column base. The joint fitting is deformed. Specifically, it will be deformed as shown by the solid line in FIG. A two-dot chain line (virtuality) is a state before deformation.
The deformation state of FIG. 5 will be described in more detail as follows. As the column 22 moves upward, the insertion plate 2 is drawn upward. At this time, since the receiving plate 3 is joined to the leg plate 5 on the left and right outer sides, the receiving plate 3 is deformed so that the central portion is lifted. As the receiving plate 3 is deformed, the insertion plate 2 is compressed in the width direction because the interval between the slits 10 and the interval between both leg plates 5 are reduced. At this time, since the notch-shaped recess 13 is formed in the insertion plate 2, the receiving plate 3 is easily compressed (the deformation of the receiving plate 3 by the insertion plate 2 is restricted by the notch-shaped recess in the inserting plate 2. 13 is mitigated). Further, as the insertion plate 2 is compressed, the leg plate 5 is moved inward and deformed. In addition, the base plate 4 is deformed so that the outer side of the base plate 4 is turned up from the foundation by being drawn to the leg plate 5 as the leg plate 5 is deformed. This action also contributes to the upward movement of the insertion plate 2.
As described above, according to the column base joint fitting of the present embodiment, since the notch-shaped recess 13 is formed in the insertion plate 2, the receiving plate 3 is easily deformed, and as a result, it is pulled upward. The deformation capacity of the entire column base joint fitting with respect to the load is improved, and the tolerance for the insertion plate 2 to move up is increased.

It should be noted that the present invention can be modified and embodied as follows.
-The structure of the column base joining metal fitting of the said embodiment is an example, and can also be implemented with another form.
-For example, it is also possible to apply to the column base joining metal fitting which does not have the washer 18 which has the function of adjusting the position shift of the anchor bolt as described above.
The above-described shape of the notch-shaped recess 13 of the insertion plate 2 is an example. The width and length can be changed as appropriate. Moreover, you may comprise so that two or more notch-shaped recessed parts may be provided, and it does not necessarily need to form in the left-right direction center of the insertion board 2 like the said embodiment.
-Inclusions such as packing for seismic isolation may be installed between the foundation 15 and the column base joints.
In addition, the present invention can be freely modified and implemented without departing from the spirit of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Box part, 2 ... Insertion plate as a column support plate, 3 ... Receiving plate, 4 ... Base plate, 5 ... Leg plate, 7 ... Through-hole as an attachment hole, 10 ... Slit, 13 ... Notch-shaped recessed part, 15 ... foundation, 16 ... anchor bolt as an anchor member, 22 ... pillar.

Claims (5)

In the column base joint fitting that is installed on the foundation for construction and supports the lower end of the column,
It is constructed by a receiving plate and a base plate that are arranged at intervals in the vertical direction, and leg members that are arranged opposite to both ends of the receiving plate and the base plate and are rigidly joined to the receiving plate and the base plate, respectively. A rectangular box,
A column support plate that is erected at an upper position of the box portion and that is inserted and fixed to a slit formed between the leg members of the receiving plate,
The box portion has a mounting hole formed near the center of the base plate, and is fixed to the anchor member on the foundation side through the mounting hole, and the column support plate has a notch-shaped recess opened on the lower edge side. The notch-shaped recess opens at a position lower than the backing plate, and the innermost part of the notch-shaped recess extends to a position above the backing plate . Joining bracket.   2. The column base joint fitting according to claim 1, wherein the leg members facing each other in the box portion are installed on the base plate and rigidly joined to each other.   3. The column base joint fitting according to claim 1, wherein in the box portion, the receiving plate is placed on the opposing leg member and is rigidly joined. 4.   The both ends of the said column support plate inserted are rigidly joined to the inner surface of the said leg member, The column base joining bracket in any one of Claims 1-3 characterized by the above-mentioned.   The building structure which supports a pillar using the joining bracket for pillar bases in any one of Claims 1-4.

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