JP2005307701A - Column steel frame supporting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent concrete from undergoing bearing fracture without damaging the degree of freedom in arrangement of column leg base and beautiful appearance. <P>SOLUTION: A wide width section 1b having a width larger than that of an upper section 1a of a column leg base concrete 1 is formed in a lower part of the column leg base concrete 1, the bottom end of an anchor bolt 2 is embedded to the wide width section 1b and a fixing board 4a resisting agaist pulling-out of the bolt 2 is installed on the bottom end. The position of placing the fixing board 4a is set to make the acting direction D of a stress extending conically upward from the fixing board 4a as a starting point pass through a side face of the side faces of the wide width section 1b which side face is most proximate to the bolt 2, and the size of the wide width section 1b is set to suppress the bearing fracture of the concrete at the position where the fixing board 4a is placed. By making the wide width section restrain the concrete from undergoing bearing fracture at the fixing section, the upper section 1a of the column leg base concrete can be formed in a slim shape. The concrete is prevented from undergoing bearing fracture without damaging the degree of freedom in arrangement of the column leg base and beautiful appearance. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for supporting a pillar steel frame of a building with a concrete foundation such as a steel column, a concrete steel pipe column, or a reinforced concrete steel pipe column.

  In general, a column steel frame of a building has a base plate attached to its lower end, and is fixed and supported to the column base foundation concrete by fixing this base plate to anchor bolts embedded in the column base foundation concrete. Some have been proposed (for example, Patent Documents 1 to 5).

JP 2001-20296 A JP 2001-207461 A Japanese Patent Laid-Open No. 10-8555 Japanese Patent No. 2570085 JP 2000-144902 A

  Here, a lateral load acts on the column steel frame due to an earthquake or the like, and this causes a pulling force to be applied to the anchor bolt. And by this drawing-out force, the stress which spreads conically upwards starts from the fixing | fixed part of an anchor bolt lower end acts on column base foundation concrete. For this reason, when the pulling force acts excessively, cracks occur in the column base concrete, and the concrete may be pulled out in a conical shape and destroyed, which is called cone-shaped fracture.

  Such cone-like fracture can be prevented by increasing the length of anchor bolts embedded in the column base concrete or by balancing with the compressive force acting from the base plate. Even if it does not lead to cone-like fracture, there may be a bearing failure in the concrete of the anchoring portion at the lower end of the anchor bolt. If this bearing failure occurs, the performance of the anchor bolt cannot be fully exhibited. In order to prevent this bearing failure, for example, it is possible to increase the cross-sectional area of the column base concrete. However, when the cross-sectional area is increased, the degree of freedom of arrangement of the column bases is impaired, and the aesthetics may be impaired. Furthermore, a large amount of concrete is required.

  On the other hand, a certain accuracy is required for the anchor bolt fixing position, and when a large external force is applied to the anchor bolt, it is also necessary to prevent the anchor bolt fixing portion from being caught outward. Furthermore, it is desirable that the workability is good when constructing the support structure for the column steel frame.

  Therefore, the first object of the present invention is to prevent bearing failure of concrete without impairing the degree of freedom and aesthetics of the arrangement of the column bases.

  A second object of the present invention is to easily improve the accuracy of the anchor bolt fixing position and to prevent the anchor bolt fixing portion from being caught outward.

  The third object of the present invention is to improve the workability in constructing a support structure for a column steel frame.

  According to 1st this invention, the wide part wider than the upper part of the said column base foundation concrete is formed in the lower part of column base foundation concrete. The lower end portion of the anchor bolt is embedded up to the wide portion, and a fixing plate that resists pulling out of the anchor bolt is provided at the lower end portion. Then, the direction of the stress that spreads conically upward from the fixing plate as the starting position of the fixing plate passes through the side surface of the wide portion that is closest to the anchor bolt. Thus, the size of the wide portion is set so as to suppress the concrete bearing failure at the portion where the fixing plate is disposed.

  In the present invention, the upper portion of the column base foundation concrete is slimmed down by bearing the fixing plate placement portion at the lower portion of the column base foundation concrete, that is, the suppression of concrete bearing failure at the fixing portion. Can do. Therefore, it is possible to prevent the bearing bearing failure of the concrete without impairing the degree of freedom and the appearance of the column bases. Furthermore, when anchor bolts are generally used as the main reinforcement of the column base concrete, the anchoring part of the anchoring part is liable to be subjected to bearing failure. However, in the present invention, the anchoring part is formed in the wide part and the bearing failure is suppressed. Bolts can be used as the main reinforcement of the column base foundation concrete, and the upper part of the column base foundation concrete can be further slimmed down.

The size of the wide portion that suppresses the bearing failure of the fixing portion is a circle whose radius is the length of the perpendicular from the intersection of the direction of application of the stress and the nearest side surface to the axis of the anchor bolt. The bearing area A0 defined by the area, the bearing area A1 defined by the area of the fixing plate, the concrete compressive strength σb of the wide portion, and the design bearing stress σm acting on the fixing plate are σm. ≦ σb√ (A0 / A1)
It is desirable that the size of the wide portion is set so as to satisfy the above.

  Further, in the first aspect of the present invention, the stress acting direction generated starting from the intersection point symmetrically with respect to a horizontal plane including the intersection point between the stress acting direction and the nearest side surface is the column base concrete. It is desirable that the column base concrete is designed so as to pass through the upper bottom portion.

  According to the second aspect of the present invention, there is provided a steel plate frame which is embedded in the column base concrete and is connected to each lower end portion of each anchor bolt. This steel plate frame has a hole through which each lower end portion of each anchor bolt is inserted. The anchor bolt and the steel plate frame are connected by screwing two upper and lower nuts sandwiching the steel plate frame to the anchor bolt. The lower nut is integrally provided with a fixing plate for fixing the anchor bolt to the column base concrete.

  In this invention, since the lower end part of an anchor bolt is connected with a steel plate frame, positioning of the lower end part of an anchor bolt becomes easy at the time of construction. Further, it is restricted by the steel plate frame, and it is possible to prevent the lower end portion of the anchor bolt constituting the fixing portion from protruding outward, thereby improving the fixing performance. Furthermore, among the two upper and lower nuts sandwiching the steel plate frame, at least one of the nuts is integrally provided with a fixing plate, so that the workability can be improved, and the supporting plate can take a bearing pressure for anchor bolt fixing. It is not necessary to expect the bearing pressure of the steel plate frame, and a thin steel plate frame is sufficient.

  In 2nd this invention, a horizontal reinforcing bar can also be arranged between the said steel plate frame and the upper surface of the said column base foundation concrete. According to this configuration, the strength against the splitting of the concrete is increased above the steel plate frame where the support pressure from the fixing plate acts, and the fixing performance can be improved.

  In the second aspect of the present invention, a reinforcing bar having a portion extending in the left-right direction below the steel plate frame and a portion rising upward at the side of the steel plate frame can be arranged. According to this configuration, the support pressure from the fixing plate is transmitted to the lower side of the column base foundation concrete, and the fixing performance can be improved.

  According to the third aspect of the present invention, the anchor bolt is composed of a screw-type reinforcing bar, and a hooked nut is screwed onto the upper end portion of the screw-type reinforcing bar protruding from the anchor hole of the base plate. And the filler which fills the said clearance gap is filled in the clearance gap between the upper end part of the said screw-fushi reinforcement, and the said nut with a hook.

  Columns with high leg rotation rigidity, which have no cross-sectional defects such as when using threaded steel bars as anchor bolts, have sufficient elongation capacity, and have improved adhesion to column foundation concrete. It becomes a leg structure. In the present invention, the anchor bolt is tightened by using the nut with a hook, so that a separate washer or the like is not required, so that the workability can be improved and the number of parts can be reduced. In addition, the screw fist rebar has a larger backlash of screwing of the nut than in the case of a threaded steel bar. However, in the present invention, the gap between the two is filled with the filler, so that the nut can be screwed more firmly. Further, the double nut for the detent is not necessary, and the necessary nut length of the screwed portion can be shortened. As the filler, a liquid filler that solidifies is desirable, and examples thereof include grout mortar.

  As described above, according to the first aspect of the present invention, concrete bearing failure can be prevented without impairing the degree of freedom of arrangement of the column bases and the appearance. Further, according to the second aspect of the present invention, it is possible to easily improve the accuracy of the anchor bolt fixing position, and it is possible to prevent the anchor bolt fixing portion from being caught outward. Furthermore, according to the third aspect of the present invention, it is possible to improve the workability in constructing the support structure for the column steel frame.

  Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is a structural diagram of a pillar steel support structure A according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line XX of FIG. The support structure A is provided with a plurality of anchor bolts 2 that are embedded in the column base concrete 1 and project upward from the upper surface of the column base foundation concrete 1 in the substantially vertical direction. The column steel frame 100 is supported by the column base concrete 1 by connecting the upper end of the column frame to the base plate 3 provided at the lower end of the column steel frame 100. A mortar 6 is installed between the base plate 3 and the column base concrete 1 to fill the gap. The mortar 6 is preferably a high strength non-shrink mortar.

  The anchor bolt 2 of this embodiment is comprised from a screw-fushi rebar. By adopting a threaded reinforcing bar as the anchor bolt 2, there is no cross-sectional defect as in the case of using a threaded steel bar, an external force such as an earthquake acts on the column steel frame 100, and a tensile load acts on the anchor bolt 2. Sufficient elongation capacity can be obtained. In addition, the presence of the screw-like fashi increases the adhesion to the column base foundation concrete 1 and can provide a column base structure with high leg rotation rigidity.

  A hooked nut 5 is screwed to the upper end portion of the anchor bolt 2, and the anchor bolt 2 is fastened by the hooked nut 5. FIG. 2A is a diagram showing a screwed structure of the hooked nut 5. As shown in the figure, the base plate 3 is provided with an anchor hole 3a, and the upper end portion of the anchor bolt 2 protrudes above the base plate 3 through the anchor hole 3a. Is screwed. The nut 5 with a hook is formed by integrally forming a wide hook 5a, which serves as a washer or the like. For this reason, a separate washer or the like is not required, so that the workability can be improved and the number of parts can be reduced.

  Here, in general, since the screw size is rougher than that of a threaded steel rod, the screw fuzzy reinforcing bar has a large backlash of the nut. Therefore, in this embodiment, the gap 8 between the anchor bolt 2 and the hooked nut 5 is filled with the grout mortar 7 as a filler, and this gap is filled. When the grout mortar 7 is solidified, the anchor bolt 2 and the hooked nut 5 are structurally integrated, and rattling is eliminated and the hooked nut 5 is firmly screwed. For this reason, for example, the double nut of the detent generally used conventionally becomes unnecessary. Furthermore, since a single nut is sufficient, the required nut length of the threaded portion at the upper end of the anchor bolt 2 can be shortened. In addition, as a filler with which the clearance gap 8 is filled, not only the grout mortar 7 but an adhesive agent etc. are employable. Further, in this embodiment, the grout mortar 7 which is a filler is injected and filled from above the hooked nut 5, but the injection method is not limited to this, for example, an intermediate portion of the hooked nut 5 Alternatively, a hole serving as an injection port may be perforated, and the hole may be injected and filled.

  Next, returning to FIG. 1, the column base concrete 1 of the present embodiment is formed with a wide portion 1 b having a width wider than the upper portion 1 a of the column base concrete 1 at the bottom. The lower end portion of the anchor bolt 2 is embedded in the wide portion 1b, and a hooked nut 4 is screwed to the lower end portion. A wide flange portion 4a is formed integrally with the nut 4 with the flange, and this flange portion 4a constitutes a fixing plate that resists pulling out of the anchor bolt 2 (hereinafter, the flange portion 4a is referred to as the fixing plate 4a). Also called). The fixing plate may be configured separately from the nut, but by integrating both, the number of parts can be reduced and the workability can be improved.

  The hooked nut 4 has a stress acting direction D that spreads conically upward from the fixing plate 4a (more precisely, the periphery of the fixing plate 4a) at the position where the fixing plate 4a is disposed. Among the side surfaces, the side surface is set so as to pass through the side surface closest to the anchor bolt 2. The action direction D exemplifies the direction of stress spreading in a conical shape, and the angle θ between the action direction D and the axial direction of the anchor bolt 2 is approximately 30 ° to 45 °.

  In the present embodiment, the fixing direction constituted by the fixing plate 4a is set by setting the position of the fixing plate 4a so that the action direction D passes the side surface closest to the anchor bolt 2 among the side surfaces of the wide portion 1b. The wide bearing portion 1b bears prevention of concrete bearing pressure failure at the portion so that the upper portion 1a of the column base foundation concrete 1 is not affected. Since the suppression of the bearing pressure is borne by the wide portion 1b, the upper portion 1a does not need to be wide. Therefore, the upper part 1a can be slimmed, and thus the aesthetics of the support structure A and the degree of freedom in arrangement can be improved.

  Next, setting of the size of the wide portion 1b for suppressing the concrete bearing pressure failure of the fixing portion will be described. When the tensile force from the anchor bolt 2 acts on the fixing portion, the above-described stress (supporting pressure) acts on the concrete from the fixing plate 4a. As described above, the support pressure spreads conically upward from the fixing plate 4a as the starting point. Therefore, the greater the area of the wide portion 1b that supports this support pressure, the greater the support strength. And if the bearing strength of the portion directly above the fixing plate 4a is equal to or greater than the bearing pressure of the portion immediately above, the concrete bearing failure of the fixing portion can be prevented.

  The support pressure with respect to the wide portion 1b spreads conically upward from the fixing plate 4a as described above, and the side surface closest to the anchor bolt 2 among the side surfaces of the action direction D and the wide portion 1b. It spreads to the intersection point. Accordingly, the bearing surface of the wide portion 1b is a circle centered on the axis of the anchor bolt 2 with the length r of the perpendicular from the intersection point to the axis of the anchor bolt 2 as a radius, as shown in FIG. It becomes the bearing surface of. FIG. 2B is a cross-sectional view taken along line YY in FIG. The line YY is at a position passing through the intersection position, and the support surface is a circle indicated by a broken line S as shown in FIG.

Accordingly, the area A0 (πr ² ) of the bearing surface S, the area A1 of the bearing surface of the fixing plate 4a (the area of the upper surface of the fixing plate 4a), the concrete compressive strength σb of the wide portion 1b, and the fixing plate 4a are affected. The design bearing stress σm is σm ≦ σb√ (A0 / A1)
If it is set so as to satisfy the above, it is possible to prevent the concrete bearing pressure failure of the fixing portion. This is because the bearing strength is considered to be proportional to the square root of the area ratio between the bearing surface S and the bearing surface of the fixing plate 4a. By setting in this way, even if a crack is generated along the action direction D having a conical shape, a compressive force can be transmitted on the inside thereof, so that the concrete bearing failure does not occur.

  Thus, in this embodiment, the upper part 1a of the column base foundation concrete 1 can be slimmed by bearing the suppression of the concrete bearing failure of the fixing part by the wide part 1b. Without destroying the aesthetic appearance, it is possible to prevent the concrete bearing pressure failure of the fixing portion. Furthermore, in general, when anchor bolts are used as the main reinforcement of the column base concrete, the fixing portion is liable to be subjected to bearing failure, but in this embodiment, the fixing portion by the fixing plate 4a is formed on the wide portion 1b, and the bearing failure occurs. Therefore, the anchor bolt 2 can be used as the main reinforcement of the column base concrete 1. This eliminates the need for a separate main bar and the like, and saves the labor of the bar arrangement and reduces the bar arrangement space, so that the upper part of the column base foundation concrete can be further reduced.

  The stress along the action direction D generates a stress in the action direction D ′ shown in FIG. 1A starting from the intersection position, symmetrically with respect to the horizontal plane including the intersection position. Therefore, when the stress acting direction D 'passes through the upper surface of the wide portion 1b (the portion without the upper portion 1a), the stress generated on the bearing surface S may not be supported. Therefore, as shown in FIG. 1A, the action direction D ′ passes through the bottom surface portion of the upper portion 1a (indicated by the broken line 1a in FIG. 1A), that is, the action direction D ′ is the upper portion 1a. If the column base concrete 1 is designed so as to pass through the boundary between the base portion 1 and the wide portion 1b, the stress generated in the bearing surface S can be transmitted to the lower surface of the upper portion 1a of the column base concrete 1 and the stress is transmitted. It can be fully supported.

<Other embodiments>
In the above embodiment, a plurality (eight) anchor bolts 2 are provided. However, when the number of anchor bolts 2 is increased, it is difficult to position the fixing plate 4a during construction. The position of the fixing plate 4a is important because it affects the prevention of the above-mentioned bearing failure. Therefore, in this embodiment, positioning is facilitated by connecting a steel plate frame to each lower end portion of the anchor bolt 2. FIG. 3A is a structural view of a column steel frame support structure B according to another embodiment of the present invention, and FIG. 3B is an explanatory view of attachment of the steel plate frame 9 and the anchor bolt 2. Hereinafter, the structure different from the support structure A will be described. In the support structure B, a steel plate frame 9 to which the lower ends of the anchor bolts 2 are connected is provided. This steel plate frame 9 has a hole 9a through which each lower end portion of the anchor bolt is inserted, and forms a rectangular frame plate whose inner side is hollowed out. In the case of this embodiment, since eight anchor bolts 2 are provided, eight holes 9a are also provided. The hole 9a is arranged such that the lower end portion of the anchor bolt 2 (that is, the fixing portion where the fixing plate 4a is located) is located at a predetermined position.

  The anchor bolt 2 and the steel plate frame 9 are connected by screwing two upper and lower nuts 4 and 12 sandwiching the steel plate frame 9 to the lower end portion of the anchor bolt 2. The nut 4 located on the lower side is a hooked nut having a fixing plate 4a. Accordingly, since a separate fixing plate is not required, the workability can be improved, and a supporting pressure for fixing the anchor bolt 2 can be taken by the fixing plate 4a. A thin frame 9 is sufficient. In the present embodiment, of the two nuts 4 and 12, the lower nut 4 is a hooked nut having a fixing plate 4a, but the upper nut may be a hooked nut having a fixing plate, Both nuts may be hooked nuts having a fixing plate, and at least one of them may be a hooked nut having a fixing plate.

  Thus, in this embodiment, when the lower end portion of each anchor bolt 2 is attached to the steel plate frame 9 and installed at a predetermined position in the casting form of the column base foundation concrete 1 in the construction, the fixing plate 4a is positioned. Is completed. Therefore, the positioning is greatly facilitated and the workability is improved as compared with the case where each anchor bolt 2 is positioned individually. Further, even if a load is applied to the anchor bolt 2, it is restricted by the steel plate frame 9, so that the lower end portion of the anchor bolt 2 constituting the fixing portion can be prevented from protruding outward, and the fixing performance can be improved. In the present embodiment, the steel plate frame 9 is a rectangular frame plate with the inner side cut out, but is not limited to this shape, and various shapes can be adopted. Although not shown, a Z metal fitting or the like may be fixed to the steel plate frame 9 to improve workability.

  In the support structure B, a plurality of horizontal reinforcing bars 11 are arranged between the steel plate frame 9 and the upper surface of the column base concrete 1. For this reason, the pulling force acts on the anchor bolt 2 and the support pressure from the fixing plate 4a acts. The strength against the split of the concrete is increased above the steel plate frame 9, and the fixing performance can be improved. Furthermore, in the support structure B, a U-shaped reinforcing bar 10 having a portion extending in the left-right direction below the steel plate frame 9 and a portion rising upward on the side of the steel plate frame 9 is arranged. In the case of the present embodiment, the reinforcing bar 10 has an intermediate portion extending substantially horizontally below the steel plate frame 9 and both ends have a steel plate frame 9 so as to share the tensile force generated by the support pressure from the fixing plate 4a. The fixing length is secured above and extends. By providing the U-shaped reinforcing bar 10, the support pressure from the fixing plate 4 a is transmitted to the lower part of the wide portion 1 b through the reinforcing bar 10, and the fixing performance can be improved.

  In the support structure B, the reinforcing bars 10 are formed in a U shape, but various shapes other than the U shape can be adopted. In the support structure B ′ of FIG. 4, instead of the U-shaped reinforcing bar 10, it has a portion extending in the left-right direction below the steel plate frame 9 and a portion rising upward on the side of the steel plate frame 9. The example which employ | adopted reinforcing bar 10 'which both ends fixed to the core part (part surrounded by the anchor bolt 2) of the wide part 1b is shown. Since both ends of the reinforcing bar 10 'are fixed to the core portion of the wide part 1b, the supporting pressure from the fixing plate 4a is further transmitted to the lower part of the wide part 1b via the reinforcing bar 10', thereby further improving the fixing performance. be able to. Although not shown in the drawings, hoop lines are arranged in the support structure B and the support structure B ′ so as to surround the outer periphery of the portion surrounded by the anchor bolt 2.

(A) is a structural diagram of the support structure A for pillar steel frames according to an embodiment of the present invention, (b) is a cross-sectional view taken along line XX of FIG. 1 (a). (A) is a figure which shows the screwing structure of the nut 5 with a hook, (b) is sectional drawing which follows the line YY of Fig.1 (a). (A) is structural drawing of the support structure B of the column steel frame which concerns on other embodiment of this invention, (b) is attachment explanatory drawing of the steel plate frame 9 and the anchor bolt 2. FIG. FIG. 6 is a structural diagram of a pillar steel support structure B ′ according to another embodiment of the present invention.

Explanation of symbols

A, B, B ′ Support structure for column steel 100 Column steel 1 Column base concrete 1a Upper part 1b Wide part 2 Anchor bolt 3 Base plate 4 Nut 4a collar (fixing plate)
5 Nut with hook 6 Mortar 7 Grout mortar 8 Clearance 9 Steel plate frame 10, 10 'Rebar 11 Horizontal rebar 12 Nut

Claims (9)

In the support structure of the column steel that supports the column steel by connecting the upper end of the anchor bolt protruding upward from the upper surface of the column base concrete to the base plate provided at the lower end of the column steel,
In the lower part of the column base foundation concrete, a wider part wider than the upper part of the column base foundation concrete is formed,
The lower end portion of the anchor bolt is embedded to the wide portion, and a fixing plate that resists pulling out of the anchor bolt is provided at the lower end portion.
The location of the fixing plate is
The direction of action of the stress spreading conically upward from the fixing plate as a starting point is set so as to pass through the side surface closest to the anchor bolt among the side surfaces of the wide portion,
The size of the wide part is
A support structure for a pillar steel frame, which is set so as to suppress a concrete bearing failure at a portion where the fixing plate is disposed. The size of the wide part is
Defined by the bearing area A0 defined by the area of a circle whose radius is the length of the perpendicular from the intersection of the acting direction of the stress and the closest side surface to the axis of the anchor bolt, and the area of the fixing plate The supported bearing area A1, the concrete compressive strength σb of the wide portion, and the design bearing stress σm acting on the fixing plate are σm ≦ σb√ (A0 / A1)
The column steel frame support structure according to claim 1, wherein the structure is set so as to satisfy   The action direction of stress generated starting from the intersection point symmetrically with respect to a horizontal plane including the intersection point between the action direction of the stress and the nearest side surface passes through the bottom surface portion of the upper part of the column base concrete. The support structure for a column steel frame according to claim 1 or 2, wherein a column base concrete is designed. In the construction method of the support structure of the column steel, the upper end of the anchor bolt protruding upward from the upper surface of the column base concrete is connected to the base plate provided at the lower end of the column steel to support the column steel,
In the lower part of the column base foundation concrete, a wider part wider than the upper part of the column base foundation concrete is formed,
The lower end portion of the anchor bolt is embedded to the wide portion, and a fixing plate that resists pulling out of the anchor bolt is provided at the lower end portion.
The arrangement position of the fixing plate,
The action direction of the stress spreading in a conical shape starting from the fixing plate is set so as to pass through the side surface closest to the anchor bolt among the side surfaces of the wide part,
The size of the wide portion is
A method for constructing a support structure for a column steel structure, which is set so as to suppress a concrete bearing failure at an arrangement site of the fixing plate. In the support structure of the column steel that supports the column steel by connecting the upper ends of the plurality of anchor bolts protruding upward from the upper surface of the column base concrete to the base plate provided at the lower end of the column steel,
A steel plate frame embedded in the column base concrete and connected to each lower end of each anchor bolt;
The steel plate frame has a hole through which each lower end of each anchor bolt is inserted,
The anchor bolt and the steel plate frame are connected by screwing the upper and lower two nuts sandwiching the steel plate frame to the anchor bolt,
A support structure for a column steel structure, wherein at least one of the nuts is a nut integrally provided with a fixing plate for fixing the anchor bolt to the column base concrete.   6. The support structure for a column steel frame according to claim 5, wherein the anchor bolt is composed of a screw-type reinforcing bar.   The support structure for a column steel frame according to claim 5 or 6, wherein a horizontal reinforcing bar is arranged between the steel plate frame and the upper surface of the column base foundation concrete.   The reinforcing bar having a portion extending in the left-right direction below the steel plate frame and a portion rising upward at the side of the steel plate frame is arranged. Support structure for pillar steel frame. In the support structure of the column steel that supports the column steel by connecting the upper end of the anchor bolt protruding upward from the upper surface of the column base concrete to the base plate provided at the lower end of the column steel,
The anchor bolt is composed of a threaded reinforcing bar,
A nut with a hook is screwed onto an upper end portion of the screw-fushi reinforcing bar protruding from the anchor hole of the base plate, and a filling material for filling the gap is filled in a gap between the upper end portion of the screw-fushi reinforcing bar and the nut with the hook. A support structure for pillar steel frames characterized by

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