JP2004346509A - Washer for anchoring column base - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a washer for anchoring a column base, which can be easily and inexpensively manufactured, and which enables the completion confirmation of air vent and filling in the injection of mortar. <P>SOLUTION: An upper end of an anchor bolt 12, which is embedded in base concrete 11, is protruded from a base plate 22 of the steel column base 20, and a nut 13 is screwed into a protruded part, so that the column base 20 can be anchored. The washer 15 is sandwiched between the base plate and the nut. The washer 15 is composed of a spring washer in an almost C-shape in a plan view, comprising an insertion hole 15a into which the anchor bolt is to be inserted, and a notch 15b which leads from an inner peripheral surface of the insertion hole 15a to an outer peripheral surface of the washer 15. The mortar 30, which is filled between the base plate and the base concrete, is discharged from the notch 15b via a bolt hole 22a of the base plate and the insertion hole 15a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure for fixing a steel column base to a foundation, and more particularly to a washer for a nut screwed into an upper end portion of an anchor bolt protruding from a base plate of the column base.
[0002]
[Prior art]
For example, according to the fixing method of the steel column base described in Patent Document 1, the upper end portion of the anchor bolt is protruded from the foundation concrete, and this is passed through the bolt hole of the base plate of the steel column base. Then, a washer is fitted and the nut is screwed. A concave groove is formed on the lower surface of the washer, and a through hole is formed from the concave groove to the upper surface of the washer.
[0003]
Next, among the plurality of washers corresponding to the plurality of anchor bolts, mortar is injected from the through hole of one washer. The mortar is filled in the gap between the base plate and the foundation through the concave groove and the gap between the bolt hole of the base plate and the anchor bolt. And it flows out from a through-hole through the concave groove of another washer.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 60-258345 (2nd page, FIG. 2)
[0005]
[Problems to be solved by the invention]
The washer described in the above document has to be formed with a ditch or through hole, and is not easy to manufacture and is expensive.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a column base fixing structure in which an upper end portion of an anchor bolt embedded in a foundation concrete is protruded from a base plate of a steel column base, and a nut is screwed into the protruding portion. In this case, a washer for fixing the column base sandwiched between the base plate and the nut, an insertion hole through which the anchor bolt passes, and a notch portion extending from the inner peripheral surface of the insertion hole to the outer peripheral surface of the washer. The mortar filled between the base plate and the foundation concrete has a gap between the inner peripheral surface of the bolt hole of the base plate and the anchor bolt, and an inner peripheral surface of the insertion hole. It is possible to discharge from the notch through a gap between the anchor bolt and the anchor bolt. As a result, the structure can be simplified, and it can be easily and inexpensively manufactured. In addition, it is possible to easily and surely confirm the completion of air venting and filling during mortar injection.
[0007]
The column base fixing washer according to the present invention is preferably formed of a spring washer. As a result, the nut can be surely prevented from loosening, and as a result, the fixing strength of the column base can be improved.
[0008]
The column base fixing washer according to the present invention may be constituted by a flat washer. As a result, the manufacturing can be further facilitated and the cost can be further reduced.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a fixing structure of the steel column base 20 to the foundation 10. A plurality of anchor bolts 12 (only two are shown in the figure) are embedded in the concrete 11 of the foundation 10 vertically. The upper end portion of the anchor bolt 12 protrudes from the upper surface of the foundation concrete 11.
[0010]
A steel column base 20 is built above the foundation concrete 11 via a level adjusting mortar 40. The column base 20 includes a vertical column base body 21 and a base plate 22 provided at the lower end of the column base body 21. The base plate 22 projects from the peripheral side portion of the column base body 21 in a flange shape. Bolt holes 22a are opened in the base plate 22, and the anchor bolts 12 are inserted into the bolt holes 22a. A nut 13 is screwed to the upper end protruding portion of the anchor bolt 12.
[0011]
A washer 15 is bitten between the nut 13 and the base plate 22. As shown in FIG. 2, the washer 15 has a central insertion hole 15a and a notch 15b extending from the insertion hole 15a to the outer peripheral surface, and has a C-shape in plan view. The inner diameter of the insertion hole 15 a is sufficiently larger than the outer diameter of the anchor bolt 12. The anchor bolt 12 is passed through the insertion hole 15a.
[0012]
The washer 15 is composed of a spring washer. That is, the washer 15 is made of an elastic material such as spring steel. As shown in FIG. 3, the height of the washer 15 when not deformed gradually changes along the circumferential direction. On the other hand, as shown in FIG. 1, the washer 15 sandwiched between the nut 13 and the base plate 22 by tightening the nut 13 is deformed flat.
The washer 15 has a uniform thickness along the circumferential direction.
[0013]
The gap between the base plate 22 and the foundation concrete 11, the gap between the inner peripheral surface of the bolt hole 22a and the anchor bolt 12, the gap between the inner peripheral surface of the insertion hole 15a and the anchor bolt 12, and the notch 15b. The mortar 30 is filled with bedding.
[0014]
A construction method of the column base fixing structure having the above-described configuration will be described.
First, the base 10 is constructed such that the upper end of the anchor bolt 12 protrudes from the concrete 11. The level adjusting mortar 40 is placed on the upper surface of the foundation concrete 11. Then, the column base 20 is installed, and the anchor bolt 12 is inserted into the bolt hole 22 a of the base plate 22. A washer 15 is fitted to the upper end portion of the anchor bolt 12, and the nut 13 is screwed and tightened. By this tightening, the washer 15 is elastically deformed until it becomes flat. As a result, the nut 13 can be reliably prevented from loosening, and as a result, the fixing strength of the column base 20 can be improved.
[0015]
Next, the mold frame 50 is abutted against the peripheral end surface of the base plate 22 and is installed so as to surround a gap between the base plate 22 and the foundation concrete 11. A mortar injection groove 50 a is formed on one inner surface of the mold 50. The groove 50 a extends downward from the upper end surface of the mold 50 and continues to a gap between the base plate 22 and the foundation concrete 11.
[0016]
A mortar injection nozzle 60 is inserted into the upper end opening of the groove 50a, and the mortar 30 is discharged from the nozzle 60. Thereby, the mortar 30 is filled in the gap between the base plate 22 and the foundation concrete 11 through the groove 50a. At this time, the air in the gap sequentially passes through the gap between the inner peripheral surface of the bolt hole 22a and the anchor bolt 12, the inner peripheral surface of the insertion hole 15a and the gap between the anchor bolt 12, and the notch 15b. Can escape.
[0017]
Thereafter, the mortar 30 is filled in the gap between the inner peripheral surface of the bolt hole 22a and the anchor bolt 12, and further, the gap between the inner peripheral surface of the insertion hole 15a and the anchor bolt 12 is filled. And it comes out through the notch 15b. Thereby, it can be confirmed that the mortar filling is completed.
[0018]
As described above, according to the present invention, by using the C-shaped washer 15, it is possible to easily and surely confirm the completion of air venting and filling during mortar injection. The C-shaped washer 15 has a very simple structure and can be manufactured very easily by a press or the like. Thereby, the manufacturing cost can be greatly reduced.
[0019]
The present invention is not limited to the above embodiment, and various forms can be adopted.
For example, the washer may be a plain washer (C-shaped flat plate) instead of the spring washer.
The outer peripheral shape of the washer is not limited to a circle, but may be a non-circular shape such as a square shape.
[0020]
【The invention's effect】
As described above, according to the washer for fixing a column base according to the present invention, it is possible to reliably confirm the completion of air venting and filling at the time of mortar injection, despite the extremely simple structure. As a result, the manufacturing can be facilitated, and the manufacturing cost can be greatly reduced.
[Brief description of the drawings]
FIG. 1 is a front cross-sectional view showing a column base fixing structure according to an embodiment of the present invention in a state when a mortar injection operation is completed.
FIG. 2 is a plan view of the washer of the column base fixing structure.
FIG. 3 is a side view of the washer.
[Explanation of symbols]
10 foundation 11 foundation concrete 12 anchor bolt 13 nut 15 washer 15a insertion hole 15b notch 20 steel column base (steel column base)
21 Column base 22 Base plate 30 Laying mortar

Claims (3)

The upper end of the anchor bolt embedded in the foundation concrete protrudes from the base plate of the steel column base, and is sandwiched between the base plate and the nut in the column base fixing structure in which a nut is screwed into the protrusion. A washer having an insertion hole for passing the anchor bolt and a notch extending from the inner peripheral surface of the insertion hole to the outer peripheral surface of the washer, and having a substantially C shape in plan view. The mortar filled with the concrete can be discharged from the notch through the gap between the inner peripheral surface of the bolt hole of the base plate and the anchor bolt and the gap between the inner peripheral surface of the insertion hole and the anchor bolt. A washer for fixing the column base. 2. The washer for fixing a column base according to claim 1, wherein the washer is constituted by a spring washer. The column washer fixing washer according to claim 1, comprising a flat washer.

Images