JP4483087B2 - Anchor bolt construction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anchor bolt construction method suitable for use when fixing a plate or the like on which a tensile force acts to a mounting surface of a reinforced concrete structure.
[0002]
[Prior art]
As is well known, when a reinforced concrete mounting part is integrally constructed on the foundation, etc., and a steel column or the like is erected on this mounting part, the head is placed at a predetermined position when the mounting part is placed in advance. Anchor bolts are embedded so that the male screw of the part protrudes, and the head of the anchor bolt is inserted into the bolt hole of the base plate provided on the column base of the steel column, and the nut is tightened, or the upper end An anchor bolt having a cap nut is embedded in the portion, and a bolt inserted from the bolt hole of the base plate is tightened into the cap nut, whereby a structure in which both are integrally coupled is adopted.
[0003]
[Problems to be solved by the invention]
By the way, in the conventional construction method in which such an anchor bolt is embedded in the mounting portion, when the concrete of the mounting portion is placed, the anchor bolt is displaced, and as a result, the anchor bolt is accurately placed. There was a problem that it was difficult to construct at a predetermined position.
[0004]
In particular, when fixing a plate or the like on which a tensile force acts, such as when fixing the base plate of a steel column base, as shown in FIG. It is necessary to embed the anchor bolt 3 with 2 and the anchor bolt 5 having the male screw portion 4 at the head. These anchor bolts 3 are bent in a hook shape in order to increase the tensile resistance, and have a sufficient fixing length. There is a problem that it is easy to occur and therefore it becomes more difficult to construct with high accuracy. To solve this problem, additional work such as positioning of the anchor bolts 3 and 5 using a separate fixing jig occurs. There were drawbacks.
[0005]
On the other hand, as a fixing member of this type, there is a seismic isolation device interposed in a foundation portion or an intermediate floor of the structure in order to improve safety at the time of an earthquake. In this seismic isolation device, it was designed on the premise that a vertical load is always applied from the upper structure both in normal times and during earthquakes, but the upper structure in which the seismic isolation device is interposed is high-rise, When the aspect ratio is large, or when the vertical motion component of the earthquake motion is large, regardless of the shape of the building, etc., it is assumed that a location where tensile force acts on the seismic isolation device may occur when an earthquake occurs Has been.
[0006]
Therefore, in such a case, it is necessary to fix the base plate for attaching the seismic isolation device to the foundation or the pillar using the anchor bolts 3 and 5 as shown in FIG. In this case, since high mounting accuracy is required, there is a strong demand for measures for ensuring positioning accuracy when the anchor bolts 3 and 5 are installed.
[0007]
The present invention has been made in view of such circumstances. When fixing a fixing member to a reinforced concrete structure mounting portion, the anchor bolt can be embedded in a predetermined position of the mounting portion easily and with high accuracy. The purpose is to provide a construction method.
[0008]
[Means for Solving the Problems]
An anchor bolt construction method according to the present invention as set forth in claim 1 is an anchor bolt construction method for fixing a fixing member to a reinforced concrete structure attachment portion via an anchor bolt, and a part of the attachment portion. In this case, the anchor bolt is fixed at one end and the width of the opening is wider than the thickness of the reinforcing bar to be inserted in the subsequent step. A step of embedding the sleeve formed with the opening so that the opening opens on the surface of the part, a cap nut protruding from the fixing member or a bolt protruding from the fixing member, and the cap nut or bolt Attaching the reinforcing bars integrally, and inserting the reinforcing bars into the sleeve and positioning the fixing member on the constructed part. In the step of filling the grout into the sleeve, by forming by Da設a concrete foundation portion of the fixing member in the attachment portion on the portion between the portion and the fixing member, the And a step of integrating the base portion with the portion.
[0009]
According to the anchor bolt construction method having the above-described structure, a part of the reinforced concrete attachment portion is first placed, and the sleeve and the anchor bolt attached thereto are buried, and a fixing member is provided in the wide-mouth opening of the sleeve. The fixing member and the anchor bolt are integrated by inserting a reinforcing bar extending from the core and filling and solidifying the grout in the sleeve, so when constructing a part of the mounting part, the position of the anchor bolt Even when a deviation occurs, the error due to the positional deviation can be absorbed by the clearance between the sleeve and the reinforcing bar.
[0010]
As a result, the fixing member can be easily fixed at a predetermined position with high accuracy. In addition, by filling and solidifying the grout in the sleeve, the positioning of the fixing member is ensured, so that concrete is placed between a portion of the mounting portion and the fixing member to place the foundation portion of the mounting portion. Even in the construction, it is not necessary to use a jig for fixing the fixing member, and the work becomes easy.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a basic embodiment of an anchor bolt 11 embedded in a mounting portion 10 by the anchor bolt construction method according to the present invention, and FIG. The construction completion figure at the time of applying to the attachment part of the seismic device 12 is shown.
The above-described embodiment will be described sequentially based on FIGS. 3 to 5. First, as shown in FIG. 3, a part 10 a of the mounting portion 10 is constructed on the foundation in order to place the seismic isolation device 12.
[0012]
At this time, a predetermined reinforcing bar 13 is arranged in the portion 10a, and the sleeve 14 and the anchor bolt 11 are installed. The sleeve 14 has an anchor bolt 11 inserted at a lower end (one end), and an opening 15 having a wider opening than the thickness of a reinforcing bar 22 inserted in a later process is formed at the upper end (the other end). Has been. Further, the lower end side wall of the sleeve 14 is connected to the lower end portion of the grout injection pipe 16, and the lower end portion of the air venting and grout discharge pipe 17 is connected to the upper end side wall. The sleeve 14 is installed in a state where the opening 15 and the upper ends of the injection tube 16 and the discharge tube 17 are positioned above the placement surface of the portion 10a. Further, as shown in FIG. 2, the anchor bolt 11 has a predetermined fixing length, and its lower end is bent in a hook shape.
[0013]
And after constructing these rebar 13 and sleeve 14 grade | etc., The said part 10a is constructed | assembled by placing concrete 18.
On the other hand, as shown in FIG. 4, the base plate (fixing member) 20 for attaching the seismic isolation device 12 has a cap nut at a position corresponding to the bolt insertion hole 12 b formed in the lower flange 12 a of the seismic isolation device 12 in advance. 21 is fixed, and a reinforcing bar 22 is joined to the lower end of the cap nut 21. Then, a predetermined reinforcing bar 23 is arranged on the part 10 a constructed in the process shown in FIG. 3, the base plate 20 is faced, and the reinforcing bar 22 is inserted from the opening 15 of the sleeve 14 and positioned.
[0014]
In this way, by positioning the base plate 20, even when the sleeve 14 and the anchor bolt 11 are misaligned when the portion 10 a is constructed, the clearance between the wide-mouthed sleeve 14 and the reinforcing bar 22 is also used. Errors due to the above-mentioned positional deviation are absorbed. Then, the grout 24 is filled into the sleeve 14 from the injection tube 16 and solidified. Thereby, the base plate 20 is fixed on the said part 10a in the state in which the horizontal accuracy of the installation surface and the position accuracy of the cap nut 21 were ensured.
[0015]
Next, as shown in FIG. 5, concrete 25 is placed between the portion 10 a and the base plate 20, and the foundation portion 10 b of the mounting portion 10 is integrally constructed. Thereby, the basic form part for embedding the anchor bolt 11 as shown to the left of FIG. 1 is constructed | assembled.
Then, the seismic isolation device 12 is installed on the constructed mounting portion 10, and the bolt 26 inserted from the bolt insertion hole 12 b formed in the lower flange 12 a is fastened to the cap nut 21. To fix. FIG. 2 shows a state where the installation of the seismic isolation device 12 has been completed.
[0016]
As described above, according to the anchor bolt construction method having the above-described configuration, first, a portion 10a of the reinforced concrete mounting portion 10 is placed, and the anchor bolt 11 and the sleeve 14 having an opening formed in the wide mouth are embedded. Next, the base plate 20 is positioned by inserting the reinforcing bar 22 suspended from the cap nut 21 of the base plate 20 into the sleeve 14 and filling and solidifying the grout 24 in the sleeve 14. Even when the anchor bolt 11 is displaced when the part 10 a is constructed, the error caused by the displacement can be absorbed by the clearance between the sleeve 14 and the reinforcing bar 22.
[0017]
As a result, the base plate 20 can be easily fixed at a predetermined position with high accuracy. In addition, by filling and solidifying the grout 24 in the sleeve 14, the base plate 20 is reliably positioned, so that the concrete 25 is placed between the portion 10 a of the mounting portion 10 and the base plate 20. Even when the base portion 10b of the portion 10 is constructed, it is not necessary to use a jig for fixing the base plate 20, the work becomes easy and the economy is excellent.
[0018]
In the above-described embodiment, the sleeve 14 has been described as having a shape in which the anchor bolt 11 is inserted into the lower end portion. However, the present invention is not limited to this, and a female screw is formed at the lower end portion. It is also possible to apply a type in which both are screw-fixed by forming a male screw at the upper end of the bolt.
As the anchor bolt 11, in addition to the above-described bent hook shape, for example, an anchor plate attached, or other various anchor bolts having a large fixing length can be applied.
[0019]
Further, the fixing member is not limited to the base plate 20, and instead of the cap nut 21 and the reinforcing bar 22, a male screw 28 as shown on the right side of FIG. You may use the volt | bolt 29 which functions as.
Further, the reinforcing bars 13 and 23 in the part 10a and the base part 10b of the reinforced concrete structure 10 are not limited to the arrangement and procedure as shown in the embodiment, but may be arranged in an appropriate form as necessary. If rebars can be applied and further not required, the rebars 13 and 23 can be omitted.
[0020]
【The invention's effect】
As described above, according to the anchor bolt construction method of the present invention described in claim 1, even when the anchor bolt is misaligned when the part of the mounting portion is constructed, the sleeve and the reinforcing bar The clearance between the fixing member and the fixing member can absorb the error due to the above-described positional deviation, and thus the fixing member can be easily fixed at a predetermined position with high accuracy. When constructing the foundation portion of the mounting portion by placing concrete on the base, it is not necessary to use a jig for fixing the fixing member, and an effect of facilitating the work can be obtained.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a state of an anchor bolt embedded in a mounting portion according to an embodiment of an anchor bolt construction method according to the present invention.
FIG. 2 is a longitudinal sectional view showing a completed state when the construction method of FIG. 1 is applied to a mounting portion of a seismic isolation device.
3 is a longitudinal sectional view showing a state in which the construction of a part in which a sleeve is embedded is completed in the construction process of FIG. 2;
4 is a longitudinal sectional view showing a state in which a base plate is installed on a part of FIG. 3. FIG.
FIG. 5 is a longitudinal sectional view showing a state in which a base portion is constructed between the base plate and a part of FIG. 4 and a base isolation device is attached to the base plate.
FIG. 6 is a longitudinal sectional view showing a state of an anchor bolt embedded in a mounting portion by a conventional anchor bolt construction method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Attachment part 10a Part 10b of attachment part 11 Base part 11 Anchor bolt 12 Seismic isolation device 14 Sleeve 15 Opening part 16 Grout injection pipe 17 Air venting and grout discharge pipe 20 Base plate (fixing member)
21 Cap nut 22 Reinforcement 29 Bolt (rebar)

Claims (1)

An anchor bolt construction method for fixing a fixing member to a reinforced concrete structure attachment portion via an anchor bolt,
A part of the mounting part is placed at a distance from the fixing member. At this time, an anchor bolt is fixed to one end part of the part, and a reinforcing bar inserted into the other end part in a later process A step of embedding the sleeve in which the opening having a wider opening than the thickness is formed so that the opening opens on the surface of the part;
A step of integrally attaching the cap nut or the bolt protruding from the fixing member to the fixing member, and the reinforcing bar continuous to the cap nut or the bolt;
On the constructed part, inserting the rebar into the sleeve to position the fixing member and filling the sleeve with grout;
Forming concrete between the part and the fixing member to form a base part of the fixing member in the mounting portion on the part, thereby integrating the base part with the part. An anchor bolt construction method characterized by that.

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