JP2003138650A - Column base fixing structure and coupling device for building of steel construction - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance earthquake resistance by properly absorbing seismic energy, in a column base fixing structure and a component coupling device for a building of steel construction. SOLUTION: A base 3 is fixed to a lower end of a column base 1, and placed on a concrete foundation 2. A plurality of anchor bolts 4 are vertically embedded in the concrete foundation 2. An upper end of the anchor bolt 4 serves as a screw part 41, and passes through the base 3. A lower part of the screw part 41 is located below the top surface of the concrete foundation 2. The base 3 is fixed to the anchor bolts 4 in a state of being sandwiched between upper and lower nuts 51 and 52 into which the screw parts 41 are screwed. The downside nut 52 is embedded in the concrete foundation 2. In the anchor bolt 4, a sectional area of a part below the screw part 41 is made smaller than an effective sectional area of the screw part 41. Thus, a part, which is located below the screw part 41 near the screw part 41, serves as a region Y due to yield, which preferentially yields during earthquakes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a column base fixing structure for a steel structure and a connecting device having a common problem with the structure.

[0002]

2. Description of the Related Art As shown in FIG.
Is configured by connecting steel frames (H-shaped steel, steel pipes, etc.) that will be columns and beams. Each pillar 1 of this building A
It is fixed to a concrete foundation 2 (or foundation beam) via a base plate 3 (base) and a plurality of anchor bolts 4.

As shown in detail in FIG. 7, a base plate 3 is fixed to the lower end of the column base 1 by means of welding or the like to form the column base 1.
Horizontally overhangs and is placed on the top surface of the concrete foundation 2. A plurality of through holes 3 a are formed in the base plate 3. The anchor bolt 4 is vertically embedded in the concrete foundation 2. The upper end portion of the anchor bolt 4 projects from the concrete foundation 2, penetrates the through hole 3a of the base plate 3, and projects from the upper surface thereof. A screw portion 4a is formed on the upper end portion of the anchor bolt 4, and a nut 51 is screwed into the screw portion 4a, and the nut 51 is tightened toward the base plate 3 so that the base plate 3 is fixed via the anchor bolt 4. It is fixed to the foundation 2 and thus the column base 1 is the concrete foundation 2
Fixed to. The lower end portion of the anchor bolt 4 is bent to form a fixing portion 4b.

First, the operation of a general column base fixing structure without the lower nut 52 will be described. During an earthquake,
When the building A swings horizontally as shown by the arrow in FIG. 6, a moment acts on the column base 1, and this moment is transmitted to the anchor bolt 4 via the base plate 3. When the swing is large and the moment is large, the anchor bolt 4 yields at a portion embedded in the concrete foundation 2 in the vicinity of the upper surface of the concrete foundation 2 and this portion extends. When the column base 1 leans to the right, the left anchor bolt 4 extends, and when the column base 1 leans to the left, the right anchor bolt 4 extends.

In the column base fixing structure, tension,
The alternating load of compression could not be satisfactorily taken over by the anchor bolt 4, and seismic energy could not be absorbed well. That is, the anchor bolt 4 extends due to the first swing. However, even if the base plate 3 returns to a position where it comes into contact with the upper surface of the concrete foundation 2 thereafter, the nut 51 does not follow the base plate 3 and the anchor bolt 4 remains in an extended state. As described above, once the anchor bolt 4 extends, it loses the function of absorbing seismic energy unless larger shaking occurs.

Therefore, as shown in FIG. 7, the lower nut 5
A pedestal fixing structure with 2 is also being developed. The lower nut 52 is screwed into the screw portion 4 a of the anchor bolt 4 and embedded in the concrete foundation 2 to receive the lower surface of the base 2. According to this configuration, since the anchor bolt 4 that has once expanded receives the compressive load from the base plate 3 via the lower nut 52 and returns to its original state, it is repeatedly deformed while bearing the tensile and compressive loads, and seismic energy is reduced. It was expected to be absorbed.

[0007]

However, in the fixing structure of FIG. 7, when the anchor bolt 4 receives a tensile load, the screw portion 4a has a portion between the nuts 51 and 52 (that is, the through hole 3a of the base plate 3). Yield occurs in the part housed inside, and as a result, play is generated between the nuts 51 and 52 and the base plate 3, so that compression and tensile loads cannot be fully taken care of, and it was expected. It could not absorb seismic energy as well.

The drawback of the above-mentioned column base fixing structure is more universal when the anchor bolts 4, nuts 51, 52 are viewed as a connecting device for connecting the two components of the concrete foundation 2 and the base plate 3. Will be things.

[0009]

According to the present invention, (a) a base fixed to a lower end of a column base is mounted on a concrete foundation, and (b) a base having a plurality of through holes is vertically embedded in the concrete foundation. A plurality of anchor bolts penetrating through the through holes of the base and protruding from the base; and (c) a fixing means for fixing the base to the anchor bolt, wherein the fixing means is provided on the anchor bolt and In a column base fixing structure having a receiving portion that is embedded in a concrete foundation and receives the lower surface of the base, and a nut that is screwed into a screw portion of an anchor bolt formed above the receiving portion and tightens the base from above, In the anchor bolt, the anchor bolt is located below the receiving portion in the vicinity of the receiving load compared to the yield load of the portion between the nut and the receiving portion. Small-position of the yield load, site located this downward, characterized in that it is provided as the yield region where surrender preferentially than other parts of the anchor bolt during an earthquake.

According to the above construction, when the column base receives a moment in one direction during an earthquake, the anchor bolt receives a tensile load from the base via the nut, and the expected yielding area near the receiving portion yields. extend. When the column base receives a moment in the opposite direction, the anchor bolt receives a compressive load from the base plate via the receiving portion, whereby the once-expanded expected yield region is compressed and deformed and returns to its original length. At the time of yielding in the expected yielding area, the portion between the nut and the receiving portion does not yield, and backlash does not occur between the base and the nut and the receiving portion. As a result, the tensile and compressive loads from the base can be transmitted to the anchor bolts via the nuts and receiving parts, so that plastic deformation can be repeated while bearing the tensile and compressive loads in the expected yield region of the anchor bolts, and seismic energy Can be absorbed well.

Preferably, the receiving portion is formed longer than the elongation amount of the expected yielding region corresponding to the largest earthquake motion. As a result, even if the largest earthquake motion occurs,
By the contact between the receiving portion and the concrete, it is possible to bear the shear load, and the expected yielding region hardly receives the shear load and can stably bear the alternating load.
Preferably, the threaded portion of the anchor bolt extends to a position below the upper surface of the concrete foundation, the receiving portion is constituted by a lower nut screwed to the lower portion of the threaded portion, and the cutoff of the expected yielding area is performed. The area is smaller than the effective area of this thread. Thereby, the anchor bolt having the above-mentioned function can be easily manufactured. Preferably, in the anchor bolt, the cross-sectional area of the intermediate portion including the expected yielding area is smaller than the effective cross-sectional area of the screw portion and the cross-sectional area of the lower end portion, and the lower end portion is provided as a fixing portion to the concrete foundation. It As a result, the anchor bolt itself can have a fixing function, and the number of parts of the fixing structure can be reduced. More preferably, the bond strength between the expected yielding area of the anchor bolt and the concrete foundation is substantially zero. As a result, it is possible to more surely give priority to the breakdown in the expected breakdown region.

Further, the connecting device of the present invention is used for connecting the first constituent member and the second constituent member having the through hole, and is fixed to the first connecting member to penetrate the second constituent member. A connecting rod penetrating the hole, the connecting rod of the second
A threaded portion is formed at the end protruding from the component, a nut is screwed into the threaded portion, and a receiving portion facing the nut is provided on the connecting rod. The receiving portion and the nut form the second component. The second component is fixed to the connecting rod by being sandwiched. In the connecting rod, as compared with the yield load of the portion between the nut and the receiving portion, the second load in the vicinity of the receiving portion is increased.
The yield load of the part on the side opposite to the component is small,
The part opposite to the component is provided as a planned yielding region that yields preferentially over other parts of the connecting rod.

According to the above construction, when a tensile load and a compressive load are applied to the connecting rod, the expected yielding region is plastically deformed and the portion between the receiving portion and the nut does not yield, so that the second component material is used. There is no play between the receiving part and the nut.
As a result, it is possible to favorably absorb impact energy such as seismic energy while bearing the alternating load.

Preferably, the first component is made of concrete, and the connecting rod is fixed to the first component with the expected yielding area and the receiving portion embedded in the concrete of the first component, The bond strength between the expected yielding area and the concrete is substantially zero, and the receiving portion is flush with the concrete surface. As a result, it is possible to reliably and preferentially yield the planned yield region. Further, since the receiving portion and the concrete come into contact with each other, it is possible to bear a shearing load, and this yielding scheduled region receives almost no shearing load, and can stably bear the alternating load.

Preferably, the threaded portion of the connecting rod is
The receiving portion is configured by another nut that extends from one end of the connecting rod to the opposite side through the second component, and is screwed to the threaded portion on the opposite side, and the receiving portion is formed, and the intermediate portion including the yielding region is formed. The cross-sectional area is smaller than the effective cross-sectional area of the screw part and the cross-sectional area of the other end, and the other end is provided as a fixing part to the concrete foundation. As a result, the connecting rod itself can have a fixing function, and the number of parts of the connecting device can be reduced.

Another connecting device of the present invention is used for connecting the first and second constituent members having through holes, and includes a connecting rod penetrating the through holes of the first and second constituent members. First and second screw portions are formed at both ends of the connecting rod projecting from the constituent material, and first and second nuts are screwed into the first and second screw portions, respectively. The connecting rod is provided with first and second receiving portions that face the first and second nuts, respectively, and the first receiving member and the first nut sandwich the first forming member so that the first forming member is connected to the connecting rod. The second component is fixed to the connecting rod by sandwiching the second component with the second receiving portion and the second nut. In the connecting rod, compared with the yield load of the portion between the first nut and the first receiving portion and the yield load of the portion between the second nut and the second receiving portion, the first and second receiving portions. The yield load of the portion between them is small, and the portion between the first and second receiving portions is provided as the expected yield region that yields preferentially over the other portions of the connecting rod.

According to the above construction, when a tensile load and a compressive load are applied to the connecting rod, the expected yielding region is plastically deformed and the portion between the receiving portion and the nut does not yield. There is no backlash between the component and the receiving part and the nut. As a result, it is possible to favorably absorb impact energy such as seismic energy while bearing the alternating load.

Preferably, the first and second connecting rods are provided.
Of the connecting rod extends from both ends of the connecting rod to the inside of the first and second components, and the other nuts screwed to the inside of the first and second screw portions are used to connect the first and second components. The second receiving portion is configured, and the cross-sectional area of the expected yielding area is the first and second
It is smaller than the effective area of the screw part. This can simplify the structure of the connecting rod having the above function.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. In this embodiment,
This is applied to the fixing structure of the column base 1 of the building A in FIG. 6, and the structure of the anchor bolt 4 and the structure of the fixing means 5 for fixing the anchor bolt 4 to the base plate 3 are different from the conventional fixing structure. However, the other configurations of the column base 1, the concrete foundation 2, and the base plate 3 are the same as the conventional ones, and thus detailed description thereof will be omitted.

The anchor bolt 4 of this embodiment is made of the same material such as rebar or high-strength steel over its entire length and extends vertically in the concrete foundation 2. The upper end and the lower end of the anchor bolt 4 are screw parts 41 and 43.
The root diameter of the screw portion 41 is larger than that of the conventional anchor bolt,
The diameter of the intermediate portion 42 is similar to or smaller than that of the conventional anchor bolt. That is, the diameter (cross-sectional area) of the intermediate portion 42
Is smaller than the root diameter of the screw portion 41 (effective cross-sectional area determined by the root diameter), and therefore the yield load of the intermediate portion 42 is smaller than the yield load of the screw portion 41. In the middle portion 42 of the anchor bolt 4, the diameter of the threaded portion 41 is increased.
A portion (neighboring portion) adjacent to the
Provided as. Since the viscosity and the tape are wound around the outer circumference of the expected yielding area Y, the adhesive strength between the expected yielding area Y and the concrete of the foundation 2 is substantially zero (the expected yielding area Y is On the other hand, it is not substantially attached and is unbonded).

The thread diameter of the screw portion 43 of the anchor bolt 4 is the same as that of the intermediate portion 42, and the fixing nut 45 is screwed into the screw portion 43. The anchor bolt 45 is fixed to the concrete foundation 2 by projecting the anchor nut 45 in the radial direction of the anchor bolt 4.

The enlarged screw portion 41 of the anchor bolt 4 projects from the upper surface of the concrete foundation 2 and further penetrates the through hole 3a of the base plate 3 to project from the upper surface thereof. The lower portion of the screw portion 41 is located below the upper surface of the concrete foundation 2.

The fixing means 5 for fixing each anchor bolt 4 to the base plate 3 has a pair of upper and lower nuts 51 and 52. These nuts 51 and 52 are located above and below the base plate 3 and are located in the screw portion 41 of the anchor bolt 4.
It is screwed to. Each of the nuts 51 and 52 includes, for example, a washer that abuts on the base plate 3, a nut that is tightened to the base plate 3 through the washer, and another nut that locks the nut. Show as. Lower nut 5
2 (reception part) is embedded in the concrete foundation 2, the upper surface of which is in contact with the lower surface of the base plate 3 and is flush with the upper surface of the concrete foundation 2. In FIG. 1, a hole for accommodating the lower nut 52 is indicated by reference numeral 2a. The upper nut 51 is in contact with the upper surface of the base plate 3. The base plate 3 and the anchor bolt 4 are fixed by sandwiching the base plate 3 with the pair of upper and lower nuts 51 and 52. The axial length of the lower nut 52 is longer than the amount of extension (maximum amount of extension) that occurs in the expected yielding region Y during the maximum-scale earthquake motion defined by the Building Standards Act.

The fixing work is performed as follows, for example. The lower nut 5 is previously attached to the screw portion 41 of the anchor bolt 4.
2 is adjusted in height and screwed together, and the base plate 3
Is placed on the lower nut 52, and in this state, the upper nut 51 is screwed into the screw portion 41 and tightened toward the base plate 3. Although mortar is filled below the lower nut 52 after the level adjustment, this mortar becomes a part of the concrete foundation 2.

In the fixed structure of the column base 1, the building A
When is swayed by an earthquake, a large moment is applied to the column base 1 as in the conventional structure. At this time, the anchor bolt 4 yields as in the prior art, but the method of yielding the anchor bolt 4 is different.

More specifically, as shown in FIG. 2, when a moment acts so that the column base 1 leans to the right, a tensile load is applied to the left anchor bolt 4 from the base plate 3 via the upper nut 51. Granted. At this time, in the intermediate portion 42 of the anchor bolt 4, yielding occurs in the expected yielding region Y near the screw portion 41 and the lower nut 52. This is because the yield load of the threaded portion 41 of the anchor bolt 4 is larger than the yield load of the intermediate portion 42 below it.
At this time, since the expected yielding region Y is not attached to the concrete foundation 2, the yielding is surely performed preferentially. Since the lower part of the intermediate portion 42 is attached to the concrete and the tensile load is small, yielding hardly occurs.

As shown in FIG. 2, the anchor bolt 4 is
The lower nut 6 is pulled out from the concrete foundation 2 due to the elongation accompanying the yielding of the intermediate portion 42 in the expected yield area Y, but the above-mentioned yielding area Y remains in the concrete foundation 2. This can be ensured by setting the thickness of the lower nut 52 to be equal to or more than the withdrawal length (extension amount) of the anchor bolt 4 when an assumed maximum moment occurs. Conversely, when the column base 1 leans to the left, similar yielding occurs in the right anchor bolt 4.

During the process in which the pedestal 1 shifts from the rightward tilt to the leftward tilt, the base plate 3 is moved to the concrete foundation 2
Hit the top surface of. At this time, the screw portion 4 of the anchor bolt 4
Since the lower nut 52 is screwed into the screw 1, the compression load is applied from the base plate 3 to the anchor bolt 4 via the lower nut 52 (the pushing force works). Due to this compressive load, the expected yielding region Y of the anchor bolt 4 is compressed and deformed to return to the original length. In this way, with the rolling of the building A, in the expected yielding area Y of the anchor bolt 4,
Plastic deformation can be repeated while bearing tensile load and compressive load.

As described above, yielding occurs preferentially in the expected yielding region Y of the anchor bolt 4, and the screw portion 41, particularly the portion between the nuts 51 and 52 (the portion accommodated in the through hole 3a of the base 3). You can avoid surrender at. Therefore, even if the tensile load and the compressive load are repeatedly applied, the nuts 51, 5
Since rattling does not occur between the base 2 and the base 3 and the tensile load and the compressive load from the base plate 3 can be reliably transmitted to the anchor bolt 4, it is possible to secure the plastic deformation in the above-mentioned yielding region Y and to improve the seismic energy Can be absorbed by As a result, the earthquake resistance of the building can be improved.

Although the lower nut 52 is partially pulled out from the concrete foundation 2 when a tensile load is applied, the expected yielding region Y is in the concrete foundation 2. The lower nut 52 and the peripheral surface of the accommodation hole 2a of the concrete foundation 2 can bear a horizontal shearing load, so that the expected yielding region Y receives almost no horizontal shearing load and the alternating load as described above. Can be stably managed.
Moreover, in the present embodiment, since the axial length of the lower nut 52 is longer than the extension amount of the expected yielding region Y that occurs during the largest earthquake motion, the lower nut 52 is prevented from completely coming off. Therefore, the above action can be secured.

The present invention is not limited to the above embodiment, and various forms can be adopted. In the embodiment of FIG. 3A,
The lower end portion of the anchor 4 has a larger diameter than the intermediate portion 42, and the lower end portion itself serves as the fixing portion 45A. The other configuration is similar to that of the first embodiment, and therefore the description is omitted.
In this embodiment, the screw portion 41, the intermediate portion 42, the fixing portion 4
5A is composed of one member, and the number of parts can be reduced.

In the embodiment of FIG. 3 (B), the anchor bolts 4 have substantially the same diameter over their entire length. That is, the root diameter of the screw portion 41B, the diameter of the intermediate portion 42B, and the root diameter of the lower end portion 43B are equal. However, the intermediate portion 42 including the expected yielding region Y
Unlike the other parts, the material of B has a low yield point. The other configuration is similar to that of the first embodiment, and therefore the description is omitted.

In the embodiment of FIG. 3C, the lower nut 5
2 is not used, but instead, a part of the anchor bolt 4 has a large diameter to provide the receiving portion 52C. The screw part 41 is
It is shorter than the first embodiment and is located above the receiving portion 52C. In this embodiment, the receiving portion 5 is provided in the intermediate portion 42.
2C is a site located below the planned yielding area Y
Becomes In the anchor bolt 4, the diameter (cross-sectional area, yield load) of the intermediate portion 42 is smaller than the root diameter (effective cross-sectional area, yield load) of the screw portion 42C. The other configuration is similar to that of the first embodiment, and therefore the description is omitted.

The anchor bolt fixing portion may or may not be formed by bending the lower end portion. When the anchoring portion is omitted, the lower end portion of the anchor bolt is fixed to the structure embedded in the concrete foundation. The anchor bolt may have no adhesion to concrete (may be unbonded) over the entire length below the lower nut or the receiving portion. In this case, the entire length of the unbonded area is the area to be yielded except for the bottom fixing portion. The present invention is also applicable to steel reinforced concrete structures and steel pipe concrete structures.

In the above embodiment, the concrete foundation 2 is the first constituent material, and the base 3 is the second constituent material.
It can be seen that the device for connecting the two includes the anchor bolt 4 (connecting rod), the upper nut 51, and the lower nut 52 (or the receiving portion 52C).

Another embodiment of the coupling device of the present invention will be described with reference to FIG. In this embodiment,
A wooden foundation beam 103 (first component) is placed on the concrete foundation 102 (second component). The coupling device is
Anchor bolt 104 made of the same material over the entire length
A (connecting rod) and upper and lower nuts 151 and 152 are provided. The anchor bolt 104 is vertically embedded in and fixed to the concrete foundation 102, and the upper end thereof penetrates through the through hole 103 a of the foundation beam 103 to form the foundation beam 1.
It projects above 03. The anchor bolt 104 is
The upper end has a screw portion 141, and the lower end has a fixing portion 145. Similar to the first embodiment, the diameter of the intermediate portion 142 has a smaller cross-sectional area than the root diameter of the screw portion 141 and the diameter of the fixing portion 145. In the intermediate portion 142, a portion in the vicinity of the screw portion 141 is an unbonded expected yield region Y. The screw portion 141 has a length from the upper end of the anchor bolt 104 to a position below the upper surface of the concrete foundation 102. The lower nut 152 (reception part) is housed in the recess 103 b of the foundation beam 103.

FIG. 5 shows still another embodiment of the coupling device of the present invention. In this embodiment, the floor side projection 201
(First component) and the protrusion 20 of the table on which various devices are mounted
2 (second component) is connected by the connecting rod 203 and the four nuts 211 to 214. Threaded portions 231 and 232 (first and second threaded portions) are provided at both ends of the connecting rod 203.
Are formed. The diameter (cross-sectional area, yield load) of the intermediate portion 233 is smaller than the root diameter (effective cross-sectional area, yield load) of the screw portions 231 and 232. The intermediate portion 233 is relatively short, and the entire length thereof is the yield-yield region Y.
The screw portion 231 penetrates the through hole 201 a of the protrusion 201. A nut 211 (first nut) and a nut 212 (another nut, a receiving portion) are screwed into the screw portions 231 on both sides of the protrusion 201, and the protrusion 201 is sandwiched between these nuts 211 and 212 to connect them. Rod 203 and protrusion 2
01 is fixed. The screw portion 232 penetrates the through hole 202a of the protrusion 202. A nut 213 (second nut) and a nut 214 (another nut, a receiving portion) are screwed into the threaded portions 231 on both sides of the protrusion 202. The rod 203 and the protrusion 202 are fixed.

In the connecting rod 203, the nut 2
Yield does not occur in the region between Nos. 12 and 212 and between the nuts 213 and 214, and plastic deformation is repeated preferentially in the expected yield region Y, so that seismic energy can be absorbed well.

The leg fixing structure and the connecting device of the present invention are not limited to the above embodiment, and various forms can be adopted. For example, when reducing the cross-sectional area of the expected yielding region, the cavity may be formed without changing the outer diameter.

[0040]

As described above, according to the column base fixing structure of the present invention, seismic energy can be absorbed well, and the earthquake resistance of the building can be improved. Further, according to the connecting device of the present invention, impact energy such as seismic energy can be favorably absorbed.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a column base fixing structure that constitutes an embodiment of the present invention.

FIG. 2 is a longitudinal cross-sectional view exaggeratingly showing a state at the time of an earthquake in the column base fixing structure.

3A to 3C are vertical sectional views showing other embodiments of the present invention.

FIG. 4 is a cross-sectional view showing an embodiment of a connecting device of the present invention.

FIG. 5 is a cross-sectional view showing another embodiment of the coupling device of the present invention.

FIG. 6 is a schematic view showing a steel structure to which the column base fixing structure of the present invention is applied.

FIG. 7 is a longitudinal sectional view showing a conventional column base fixing structure for a steel structure.

[Explanation of symbols]

Y Yield area 1 column base 2 Concrete foundation (first component) 3 Base plate (base, second component) 4 Anchor bolt (connecting rod) 41 Connection 42 Middle part 45 fixing unit 45A 5 fixing means 51 Upper nut 52 Lower nut (receiving part) 102 Concrete foundation (first component) 103 Foundation beam (second component) 104 Anchor bolt (connecting rod) 141 screw part 145 fixing unit 142 middle part 151 nuts 152 Nut (receiving part) 201 Protrusion (first component) 202 Protrusion (second component) 203 Connecting rod 231, 232 First and second screw parts 233 Middle part 211, 213 First and second nuts 212, 214 Other nuts (receiving part)

Continued front page    (72) Inventor Masato Koshiji             520 Yokokura Shinden, Oyama City, Tochigi Prefecture Tokyo Steel             Within the corporation F-term (reference) 2D046 AA01 AA17

Claims (10)

[Claims] 1. A base fixed to a lower end of a column base and mounted on a concrete foundation and having a plurality of through holes,
(B) a plurality of anchor bolts vertically embedded in the concrete foundation and projecting from the base by penetrating through the through holes of the base; and (c) fixing means for fixing the base to the anchor bolt. The fixing means is provided on the anchor bolt and is embedded in the concrete foundation to receive the lower surface of the base, and the screw portion of the anchor bolt formed above the receiving portion is screwed to move the base upward. In a column base fixing structure of a steel structure having a nut to be tightened from, in the anchor bolt, compared to the yield load of the portion between the nut and the receiving portion, the anchor bolt is positioned below the receiving portion in the vicinity thereof. Yield load is small in the part to be anchored, and the part located below this part yields preferentially over other parts of the anchor bolt during an earthquake. Column base fixing structure Steel of buildings, characterized in that it is provided as a constant region. 2. The column base fixing of a steel structure according to claim 1, wherein the receiving portion is formed to have a length longer than an extension amount of the expected yielding region corresponding to the largest earthquake motion. Construction. 3. A threaded portion of the anchor bolt extends to a position below the upper surface of the concrete foundation, and the receiving portion is constituted by a lower nut that is screwed into the lower portion of the threaded portion, and the expected yielding area is formed. The cross-sectional area of the thread is smaller than the effective cross-sectional area of the threaded portion.
The column base fixing structure of the steel structure described in. 4. In the anchor bolt, a cross-sectional area of an intermediate portion including the expected yielding area is smaller than an effective cross-sectional area of the screw portion and a cross-sectional area of a lower end portion, and the lower end portion serves as a fixing portion to a concrete foundation. The column base fixing structure for a steel structure according to claim 3, which is provided. 5. The steel-framed building according to claim 1, wherein the bond strength between the expected yielding area of the anchor bolt and the concrete foundation is substantially zero. Column base fixed structure. 6. A connecting device used for connecting a first component and a second component having a through hole, wherein the through hole of the second component is fixed to the first connecting member. A threaded portion is formed at an end of the coupling rod protruding from the second component, a nut is screwed into the threaded portion, and the coupling rod is provided with a receiving portion facing the nut. In the connecting device in which the second component is fixed to the connecting rod by sandwiching the second component with the receiving portion and the nut, in the connecting rod, a yield load of a portion between the nut and the receiving portion is applied. Compared with this, the yield load of the portion on the side opposite to the second component in the vicinity of the receiving portion is small, and the portion on the side opposite to the second component yields preferentially over the other portions of the connecting rod. It is provided as a planned surrender area That the coupling device. 7. The first component is made of concrete, and the connecting rod is fixed to the first component with the expected yielding region and the receiving portion embedded in the concrete of the first component, and the yielding is performed. 7. The adhesive strength between the planned region and concrete is substantially zero, and the receiving portion is flush with the concrete surface.
The connection device according to. 8. The threaded portion of the connecting rod extends from one end of the connecting rod to the opposite side through the second component, and the other portion is screwed to the threaded portion on the opposite side, whereby the receiving portion is received. The cross-sectional area of the intermediate part including the expected yielding area is smaller than the effective cross-sectional area of the screw part and the cross-sectional area of the other end, and the other end is provided as a fixing part to the concrete foundation. The connection device according to claim 6 or 7, characterized in that. 9. A connecting device used for connecting first and second components having through holes, comprising a connecting rod penetrating the through holes of the first and second components, First and second screw portions are formed at both ends protruding from the constituent material of the connecting rod, and first and second nuts are screwed into the first and second screw portions, respectively, and further, the connecting rod. Are provided with first and second receiving portions that face the first and second nuts, respectively, and the first component is fixed to the connecting rod by sandwiching the first component with the first receiving portion and the first nut. In the connecting device, the second component is fixed to the connecting rod by sandwiching the second component with the second receiving portion and the second nut. In the connecting rod, between the first nut and the first receiving portion. Compared with the yield load of the part and the yield load of the part between the second nut and the second receiving part The yield load of the portion between the first and second receiving portions is small, and the portion between the first and second receiving portions is provided as a yield-scheduled region that yields preferentially over other portions of the connecting rod. A coupling device characterized by the above. 10. The first and second screw portions of the connecting rod extend from both ends of the connecting rod to the inner side of the first and second constituent members, and are provided at portions inside the first and second screw portions. The other nuts screwed together constitute the first and second receiving portions,
The coupling device according to claim 9, wherein a cross-sectional area of the expected yielding area is smaller than an effective cross-sectional area of the first and second screw portions.