JP2023100168A - Steel frame column-beam joint structure - Google Patents

Abstract

To provide a steel frame column-beam joint structure in which the required width of a through-diaphragm is specified so that a plasticized region is formed as designed in a steel frame beam.SOLUTION: A steel frame column-beam joint structure 1 in which a steel frame column 2 is connected to a steel frame beam 3 whose width is narrower than the column width includes: a through-diaphragm 4 that has a bracket part 42 that penetrates the inside of the steel frame column and protrudes to the outside; a splice plate 5 on which the width on the steel frame column side is widened and the steel frame beam side is formed on the beam width; and a plurality of high-strength bolts 6 for joining the steel frame column side end of the splice plate to the bracket part and joining the steel frame beam side end of the splice plate to the steel frame beam. A formula defines the required width of the through-diaphragm.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a steel frame column-to-beam connection structure for connecting a steel frame beam narrower than the column width to a steel frame column.

In steel-frame buildings, as disclosed in FIG. 7 of Patent Document 1, a method of arranging a through-diaphragm at a column-to-beam joint is known. In addition, in the column-to-beam joint in the general through-diaphragm type conventional construction method, the through-diaphragm and the flange of the beam-shaped short beam bracket are joined by full penetration welding. Furthermore, the column skin plates and the webs of the short beam brackets are joined by fillet welds. The short beam bracket and the beam member are joined by high-strength bolts via the splice plate.

In such a conventional construction method, manufacturing is carried out in a steel frame manufacturing factory until the column and the short beam bracket are welded together. That is, the welding work described above is performed at a steel frame manufacturing factory, and the joining work using high-strength bolts is performed at a construction site. Full penetration welding is a very good welding method in that the stress generated in the flange can be transmitted to the diaphragm through the flange until it breaks. On the other hand, since high performance is required, in order to ensure the quality of welds, it is necessary to secure welders who require advanced skills and check for defects by ultrasonic testing (UT test) on all welds. Advanced quality control such as confirmation is required.

Here, in the conventional construction method, the beam end of the beam member in contact with the column is the starting point of the plasticized region of the beam, and as the deformation of the beam progresses, the plasticized region moves from the end of the beam toward the center of the beam member. A plasticized region will be formed. In other words, full penetration welding, which requires a high degree of quality control, is used at the portion where the bending moment generated in the beam is generally the largest during an earthquake.

On the other hand, in Patent Document 1, the width of the through diaphragm is defined by a formula so that the bolt hole position of the high-strength bolt connection farthest from the column (hereinafter referred to as "first bolt position") is the starting point of the plasticized region. The invention is disclosed. In other words, when an earthquake load occurs, only the beam side is plasticized and the bracket side of the through-diaphragm is kept within the elastic range. I'm trying to be Here, the splice plate of the column-to-beam joint of Patent Document 1 has a rectangular plate shape with the same width over the entire length of the joint.

Further, Patent Document 2 also discloses an invention of a through-diaphragm type column-to-beam joint, but does not disclose a specific regulation regarding the width of the through-diaphragm.

Japanese Patent No. 4770096 JP 2020-94344 A

However, the collapse mechanism assumed by defining the width of the through-diaphragm by the formula described in Patent Document 1 does not impose the condition that the yield at the first bolt position of the beam always precedes the beam. There are no conditions to ensure the plastic deformation capability of the joint, and the splice plate has the same width over the entire length of the joint. Moreover, Patent Document 2 does not specify the width of the through-diaphragm.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a steel column-to-beam connection structure in which a required width of a through diaphragm is defined so that a plasticized region is formed in the steel frame beam as designed.

In order to achieve the above object, the steel column-to-beam connection structure of the present invention is a steel column-to-beam connection structure in which a steel frame beam narrower than the width of the column is connected to the steel frame column, and a A through-diaphragm having a bracket portion protruding to the outside, a splice plate whose width is widened on the steel frame column side and formed to the beam width on the steel frame beam side, and the end portion of the steel frame column side of the splice plate is joined to the bracket portion. and a plurality of high-strength bolts for joining the steel beam-side end of the splice plate to the steel beam, and the required width of the through-diaphragm is defined by the following formula.

Here, the width of the widened side of the splice plate does not yield when the steel beam yields at the bolt hole position of the high-strength bolt connection by the high-strength bolt furthest from the steel frame column, and It can be configured so that it does not break until it reaches plasticity. Further, the plasticized region can be formed closer to the steel frame beam than the joint portion of the high-strength bolts arranged on the beam width side of the splice plate.

In the steel frame column-to-beam connection structure of the present invention configured in this way, the required width of the through diaphragm is defined by a mathematical formula so that the plasticized region as designed is formed in the steel frame beam. Furthermore, by widening the splice plate and imparting sufficient rigidity and strength to the joint, the steel frame beam will reach full plasticity at the position of the first bolt, and the steel frame beam will have a predetermined plastic deformation capacity. can be demonstrated.

BRIEF DESCRIPTION OF THE DRAWINGS It is the perspective view which showed the structure of the steel-frame column beam connection structure of this Embodiment. It is the perspective view which showed the structure of a steel-frame column and a through-diaphragm. It is a perspective view for explaining the construction method of the steel frame column-to-beam connection structure of the present embodiment. FIG. 4 is an explanatory diagram for explaining mathematical formulas defined in the steel frame column-to-beam connection structure of the present embodiment; BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining numerical analysis performed to confirm the effect of the steel frame column-to-beam connection structure of the present embodiment; (b) is a perspective view of an analysis model of a beam-to-column joint of a conventional construction method as a comparative example. It is a graph explaining an analysis result. FIG. 5 is an explanatory diagram for explaining how to determine the width of the splice plate on the widened side; 2 is a plan view of Structural Example 1 of the steel frame column-to-beam joint structure described in Embodiment 1. FIG. 2 is a side view of Structural Example 1 of the steel frame column-to-beam joint structure described in Embodiment 1. FIG. 2 is a plan view of Structural Example 2 of the steel frame column-to-beam joint structure described in Embodiment 1. FIG. 3 is a plan view of Structural Example 3 of the steel frame column-to-beam joint structure described in Embodiment 1. FIG. 4 is a plan view of structural example 4 of the steel frame column-to-beam joint structure described in embodiment 1. FIG. FIG. 11 is a plan view of Structural Example 5 of the steel frame column-to-beam joint structure described in Embodiment 2;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing the configuration of a steel column-to-beam connection structure 1 according to the present embodiment. 2 is a perspective view showing the configuration of the steel frame column 2 and the through diaphragm 4, and FIG.

A steel column-to-beam connection structure 1 of the present embodiment is provided at an intersection where a steel column 2 is connected to a steel frame beam 3 having a beam width narrower than the column width. In FIGS. 1 to 3, only the intersecting portions of the steel columns 2 are extracted and illustrated.

For the steel column 2, a steel frame such as a square steel pipe having a substantially rectangular shape including a substantially square shape in a plan view, a circular steel pipe, or the like can be used. Alternatively, a concrete-filled steel pipe column (CFT: Concrete Filled Tube), which is a steel pipe filled with concrete, may be used as the steel frame column 2 .

At the intersection with the beam, the interior of the steel column 2 is blocked by a through diaphragm 4 made of steel plate. Through diaphragms 4 are spaced above and below the intersection. The intersections of the steel columns 2 provided with the through diaphragms 4, 4 may be ready-made products, or may be assembled by welding as described later.

For example, the steel column 2 at the intersection is arranged above the upper through-diaphragm 4, between the upper and lower through-diaphragms 4, 4, and below the lower through-diaphragm 4. It is divided into the part that is Each portion of the steel column 2 and the through diaphragm 4 are joined by robot welding.

Details of the through diaphragm 4 will be described with reference to FIG. The through-diaphragm 4 has a penetrating portion 41 penetrating through the inside of the steel frame column 2 and a bracket portion 42 projecting to the outside, which are formed of a single integral steel plate.

For example, in the through-diaphragm 4 formed of a steel plate having a substantially octagonal shape in plan view, the bracket portion 42 is an annular portion protruding to the side of the steel column 2 having a substantially square inner edge and a substantially octagonal outer edge.

The bracket parts 42, 42 of the through-diaphragms 4, 4 projecting from above and below the intersection of the steel frame columns 2 are connected by a bracket web 43 formed of a steel plate having a substantially rectangular shape when viewed from the side.

The bracket web 43 has the same protrusion amount from the side surface of the steel frame column 2 as the bracket portion 42 and is arranged substantially at the center of each side surface of the steel frame column 2 in the width direction. The bracket web 43 is joined to the side surface of the steel column 2, the lower surface of the upper bracket portion 42, and the upper surface of the lower bracket portion 42 by fillet welding.

A plurality of bolt holes 44 for passing high-strength bolts or ultra-high-strength bolts are bored in the bracket portion 42 and the bracket web 43 . Details such as the number and positions of the bolt holes 44 will be described later.

As shown in FIG. 3, the bracket portion 42 and the bracket web 43 of the through diaphragm 4 are provided according to the positions of the respective portions of the steel beams 3 to be connected. The steel beam 3 is made of H-shaped steel, for example, and includes an upper flange 31, a lower flange 32, and a web 33 connecting them. Here, the thickness of the bracket portion 42 of the through diaphragm 4 is equal to or greater than the thickness of the flanges (31, 32) of the steel beam 3.

The bracket portion 42 of the upper through-diaphragm 4 is provided at a position to abut against the upper flange 31 of the steel beam 3, and the bracket portion 42 of the lower through-diaphragm 4 is provided at a position to abut against the lower flange 32 of the steel beam 3. be done. The bracket web 43 of the through-diaphragm 4 is provided at a position where it abuts against the web 33 of the steel beam 3 .

That is, the through-diaphragm 4 of the present embodiment has a general "function as a through-diaphragm" in the conventional technology and a "beam bracket function" for connecting the steel beams 3.

A plurality of bolt holes 34 for passing high-strength bolts or ultra-high-strength bolts are drilled in the upper flange 31, the lower flange 32, and the web 33 at the ends of the steel beam 3 in the axial direction. Details such as the number and positions of the bolt holes 34 will be described later.

The through-diaphragm 4 and the steel beam 3 which are butted in this way are joined via a splice plate 5 by high-strength bolts 6 including ultra-high-strength bolts. In short, the steel column side end of the splice plate 5 is joined to the bracket portion 42 of the through diaphragm 4 , and the steel beam side end of the splice plate 5 is joined to the steel beam 3 end.

Also, the splice plate 5 is formed of a steel plate so that the steel frame column side is widened and the steel frame beam side is the beam width. That is, the splice plate 5 spanned between the bracket portion 42 of the upper through-diaphragm 4 and the upper surface of the upper flange 31 of the steel frame beam 3 has the width of the edge portion adjacent to the steel frame column 2 expanded to about the width of the column, It is formed in a substantially trapezoidal shape in a plan view with the edge on the steel frame beam side having the width of the beam. The splice plate 5 that bridges between the bracket portion 42 of the lower through-diaphragm 4 and the lower surface of the lower flange 32 of the steel beam 3 is also formed in a similar trapezoidal shape in plan view.

On the other hand, the splice plate 5 and the splice plate 51 facing each other with the upper flange 31 or the lower flange 32 interposed therebetween have a width less than half the width of the splice plate 5 so that they can be arranged on both sides of the web 33 of the steel frame beam 3 . formed in width.

In addition, the web plate 52 that spans between both side surfaces of the bracket web 43 of the through-diaphragm 4 and the web 33 of the steel beam 3 has a height lower than that of the web 33 of the steel beam 3 and is generally rectangular in side view. Formed by steel plate.

A plurality of bolt holes 53 for passing high-strength bolts or ultra-high-strength bolts are bored in the splice plate 5, the attachment plate 51, and the web plate 52. As shown in FIG. Details such as the number and positions of the bolt holes 53 will be described later.

Next, mathematical formulas defined in the steel frame column-to-beam connection structure 1 of the present embodiment will be described with reference to FIG. 4 .
FIG. 4 shows a schematic diagram of the steel frame column-to-beam connection structure 1 of the present embodiment, and the first bolt position (A cross section position) of the steel frame beam 3 (high-strength bolt connection by the high-strength bolt 6 farthest from the steel frame column 2). The bending moment distribution at yield and full plasticity at the bolt hole position )) is illustrated.

In the steel frame column-to-beam connection structure 1 of the present embodiment, the following conditions are applied to the width (required width) of the through-diaphragm 4 at the E cross-section position in order to ensure the yield strength and plastic deformation capacity of the steel frame beam 3. I am going to impose.

<Condition 1> When the steel frame beam 3 yields at the first bolt position When yielding at the first bolt position (A cross section position), the through diaphragm 4 at the E cross section position does not yield.
<Condition 2> When Steel Frame Beam 3 is Fully Plastic at First Bolt Position When fully plastic at the first bolt position (A cross section position), the through diaphragm 4 at the E cross section position does not break.

When the above two conditions are written down as a specific conditional expression, and expanded and organized, it is as follows.
<Condition 1> When the steel frame beam 3 yields at the first bolt position When yielding at the first bolt position (A cross section position), condition 1 that the through diaphragm 4 at the E cross section position does not yield is written as follows. become.

If the yield bending strength _{E My} of the through diaphragm 4 at the E cross section position on the left side of the above equation is expressed by the effective section modulus _E Z _e at the E cross section position and the yield strength _Jd σ _y , the following equation is obtained.

Then, the effective section modulus _E Z _e can be expressed by the following equation. Note that the beam-to-column joint depth _J D is the same as the beam depth of the steel frame beam 3 .

Furthermore, substituting the expression shown in (Equation 3) into the expression shown in (Equation 2), and arranging by the effective width _E b _e considering the loss of the bolt hole 44 of the through diaphragm 4 at the E cross section position, the following is obtained. can be expressed as

This effective width _{Eb e} is obtained by the following formula using the actually required width _Eb , the number of high-strength bolts 6 _E n at the position of the E cross section, and the hole diameter d of the bolt hole 44. can be represented.

Substituting this into the equation shown in (Equation 4) and arranging it, the condition of the required width _E b of the through diaphragm 4 required so that the through diaphragm 4 at the E cross section position does not yield when yielding at the first bolt position is The following formula is obtained.

<Condition 2> When the first bolt position of the steel frame beam 3 is fully plastic When the first bolt position (A cross section position) is fully plastic, the condition 2 that the through diaphragm 4 at the E cross section position does not break can be written as follows. become that way.

Here, _{E Mu} is the breaking strength of the through-diaphragm 4 at the E section position, _E M _d is the bending moment at the E section position during full plasticity at the A section position, and α is the joint modulus smaller than 1.0.

The left side of the above equation shown in (Equation 7) is the plastic section modulus ( _Ed Z _p , _Ew Z _p ) and tensile strength ( _Jd σ _u , _Jw σ _u ), it becomes as follows.

The plastic section modulus _{Ed Zp} of the through diaphragm 4 at the E cross section position can be expressed by the following equation.

Furthermore, substituting the expression shown in (Equation 9) into the expression shown in (Equation 8), and arranging by the effective width _E b _e considering the loss of the bolt hole 44 of the through diaphragm 4 at the E cross section position, the following is obtained. can be expressed as

This effective width _{Eb e} is expressed by (Equation 5) using the actually required width _Eb , the number _E n of the high-strength bolts 6 at the position of the E cross section, and the hole diameter d of the bolt hole 44. Since it can be expressed as in the above equation, by substituting it into the equation shown in (Equation 10) and arranging it, the through-thickness required to prevent the breakage of the through-diaphragm 4 at the E cross section position during the full plasticity at the first bolt position is As a condition for the required width _Eb of the diaphragm 4, the following equation is obtained.

That is, in the steel frame column-to-beam connection structure 1 of the present embodiment, the required width of the through diaphragm 4 at the E cross-section position shown in FIG. ing.

In the steel column-to-beam joint structure 1 of the present embodiment, the splice plate 5, which is widened on the steel frame column side and formed to have a beam width on the steel frame beam side, is attached to the upper surface of the upper flange 31 and the lower surface of the lower flange 32 of the steel beam 3. They are placed facing each other. Therefore, the results of analytical examination of the effect obtained by widening the splice plate 5 will be described.

FIG. 5 shows an analysis model of numerical analysis performed to confirm the effect of the steel frame column-to-beam connection structure 1 of the present embodiment. FIG. 5(a) is a perspective view showing an enlarged main portion of an analysis model of the steel frame column-to-beam connection structure 1 of the present embodiment, and FIG. 5(b) is a conventional model analyzed for comparison. It is a perspective view of the analysis model of the beam-to-column joint of the construction method.

Here, in the analysis model of the conventional construction method, the beam cross section is modeled by two types of H-shaped steel indicated by H-600 × 300 × 12 × 25 and H-600 × 300 × 12 × 22, respectively. In the analysis model of the steel frame column-to-beam connection structure 1 of the form, the H-shaped steel represented by H-600×300×12×22 was modeled as the beam cross section of the steel beam 3 . In other words, an analysis model for the conventional construction method was also created using H-shaped steel with a flange thickness of 25 mm, which is one size thicker.

The analysis was carried out by a loading method in which the load was applied to the free end of the beam as forced displacement. Fig. 6 shows the relationship between the shear force (kN) at the free end of the beam and the member angle (rad). The analysis result of the analysis model of the steel frame column-to-beam connection structure 1 of the present embodiment is No. 3 indicated by the solid line. On the other hand, No.2 (dotted line) shows the analysis result of the conventional construction method (H-600×300×12×25) with a flange thickness one size thicker, and No.1 (dashed line) shows the steel frame of this embodiment. The analysis results of the conventional construction method (H-600×300×12×22) with the same flange thickness as the column-to-beam connection structure 1 are shown.

Looking at the analysis results in Fig. 6, in the analysis model (No.3) of the steel frame column-to-beam connection structure 1 of this embodiment, although the flange thickness is thinner than the model of the conventional construction method (No.2), , It can be seen that the same rigidity and strength as the conventional method (No. 2) are exhibited. Furthermore, when compared with the conventional construction method (No. 1) with the same flange thickness, the analysis model (No. 3) of the steel frame column-to-beam connection structure 1 of this embodiment exhibits higher rigidity and strength. I understand. It can be said that this is the result of the increased width of the splice plate 5 contributing to the improvement of member rigidity and strength.

Next, how to determine the width of the widened side of the splice plate 5 will be described with reference to FIG.

The width of the splice plate 5 that contacts the upper surface of the upper flange 31 and the lower surface of the lower flange 32 of the steel beam 3 is determined so as to satisfy the following two conditions.
<Width determination condition 1>
The width is determined so that when the steel frame beam 3 yields at the first bolt position (A section position), the splice plate 5 at the B section position and the D section position does not yield.
<Width determination condition 2>
The width is determined so that the splice plate 5 at the positions of the B cross section and the D cross section does not break when the steel beam 3 is fully plastic at the first bolt position (A cross section position).

Next, the operation of the steel frame column-to-beam connection structure 1 of the present embodiment will be described.
In the steel frame column-to-beam connection structure 1 of the present embodiment configured in this way, the required width of the through diaphragm 4 is expressed by the formula (Equation 6, Equation 11 ).

Further, since the joint portion is provided at a location where a large bending moment is input to the beam, by widening the splice plate 5, sufficient rigidity and strength are imparted to the joint portion. Furthermore, in order for the steel frame beam 3, which is a steel frame structure, to exert its plastic deformation ability, it is important to secure a plasticized region. It is designed so that the steel frame beam 3 yields at a position offset from the side of the column by ensuring a sufficient yield strength for the joint.

Specifically, as shown in FIG. 4 , the yielding of the steel beam 3 occurs starting from the bolt hole 34 (first bolt position) farthest from the side of the column. Formulas (Formula 6 and Formula 11) are defined so that the softening region is formed from the position of the first bolt toward the center side of the steel frame beam 3 .

In short, by widening the splice plate 5 and imparting sufficient rigidity and yield strength to the joint portion, the steel beam 3 will surely reach full plasticity at the position of the first bolt. It can demonstrate transforming ability.

In addition, in the steel frame column-to-beam connection structure 1 of the present embodiment, as explained in the analysis results of FIG. be able to

In addition, since there is no need to perform full penetration welding between the beam flange and the through-diaphragm as in the conventional construction method, the mechanical performance of the beam can be ensured regardless of the quality of the welded portion. Moreover, since the plasticized region of the beam is formed at a position offset from the side surface of the column, the mechanical performance of the beam is not affected by the quality of the weld. Furthermore, it is possible to reduce the number of welding man-hours in the steel frame manufacturing factory and also reduce the number of test points for ultrasonic testing (UT testing), thereby saving labor and improving productivity in steel frame manufacturing.

Also, what is manufactured at the steel frame manufacturing factory is a compact member in which the bracket portion 42 of the through diaphragm 4 protrudes as short as about 200 mm from the side surface of the steel frame column 2 at the intersection, as shown in FIG. For example, since the length of the bracket overhanging the pillar of the conventional construction method is about 1,000 mm, only two members manufactured at the factory of the conventional construction method could be loaded on one trailer, but this embodiment By using a short bracket as shown in , the number of pillars that can be loaded can be doubled, and transportation efficiency can be improved.

A specific configuration (structural example) of the steel frame column-to-beam connection structure 1 of the embodiment described above will be described below with reference to FIGS. 8 to 12. FIG. It should be noted that the same terminology or the same reference numerals will be used to describe the same or equivalent portions as those described in the above embodiment.

8 is a plan view of Structural Example 1 of the steel frame column-to-beam joint structure described in Embodiment 1, and FIG. 9 is a side view of Structural Example 1. FIG. In Structural Example 1, steel columns 2 are made of square steel pipes of 550×550×19, and steel beams 3 are made of H-shaped steel of H-600×300×12×22.

In this structural example 1, the bending moment generated in the steel beam 3 is high enough to prevent slippage between the splice plate 5 at the joint and the base material (steel beam 3 or bracket portion 42) at the time of primary design. The number of force bolts 6 is determined.

Specifically, 14 high-strength bolts 6 are required for each of the bracket side and the beam side. Fourteen high-strength bolts 6 are arranged in the bracket part 42 so that the maximum width of the splice plate 5 is the column width. At this time, the amount of protrusion of the bracket portion 42 (the distance from the side surface of the column to the tip) is 200 mm.

For example, the interval between the side of the steel frame 2 and the high-strength bolt 6 closest to the steel frame 2 is set to 100 mm, and the interval between the two rows of high-strength bolts 6 is set to 60 mm. If the width of the bridge is 40mm, add them up to get 200mm. The oblique extension c of the bracket portion 42 is 108 mm.

Here, the method of arranging the high-strength bolts 6 in the first embodiment is based on the following rails.
<Rule 1>
The standard number of rows of the high-strength bolts 6 arranged in the bracket portion 42 in the beam axis direction is two or less.
<Rule 2>
The upper limit of the maximum width of the splice plate 5 is the column width of the steel frame column 2, and if the high-strength bolts 6 cannot be arranged in this width, the high-strength bolts 6 in the beam axis direction are arranged in more than two rows. . At this time, the amount of protrusion of the bracket portion 42 is greater than 200 mm.

FIG. 10 shows the steel beam-to-column joint structure 1 of Structural Example 2 in which the steel beam 3 of Structural Example 1 is H-600×200×12×22. That is, in Structural Example 2, square steel pipes of 550×550×19 are used for the steel columns 2, and H-section steels of H-600×200×12×22 are used for the steel beams 3.

When the number of high-strength bolts 6 is determined in the same manner as in Structural Example 1, 10 high-strength bolts 6 are required for each of the bracket side and the beam side. FIG. 10 shows the arrangement result. Here, the oblique protrusion c of the bracket portion 42 is 66 mm.

FIG. 11 shows a structural example 3 in which a square steel pipe of 550×550×36 is used for the steel column 2 and an H-shaped steel of H-800×300×14×25 is used for the steel beam 3 . Also in Structural Example 3, the high-strength bolts 6 are arranged in three rows on the bracket side so that the maximum width of the splice plate 5 is equal to or less than the column width according to the above rule. Here, the oblique protrusion c of the bracket portion 42 is 195 mm.

By the way, the structural example 1-3 described above is a case where the high-strength bolt 6 is used. A different structure can be achieved by using super-high-strength bolts whose tightening axial force is about 1.5 times that of high-strength bolts.

For example, in Structural Example 1, the diagonal overhang c of the bracket portion 42 was 108 mm, and the maximum width of the splice plate 5 was 550 mm, which is the same as the column width. As shown in Structural Example 4, the oblique overhang c of the bracket portion 42 is set to 73 mm, and the maximum width of the splice plate 5 is made smaller than the column width, thereby reducing the amount of steel material.

Other configurations and effects are substantially the same as those of the above-described embodiment and other examples, so description thereof will be omitted.

A specific configuration (structural example) of the steel frame column-to-beam connection structure 1 of the embodiment described above will be described below with reference to FIG. 13 . It should be noted that the same terms or the same reference numerals will be used to describe the same or equivalent parts as those described in the embodiment or the first embodiment.

Structural Example 5 of the steel frame column-to-beam connection structure described in Example 2 differs from Structural Example 1-4 described in Example 1 above, in that the maximum width of the splice plate 5 is made wider than the column width of the steel frame column 2. there is In this structural example 5, as in structural example 3 explained with reference to FIG. of H-shaped steel is used.

As in Structural Example 3, 18 high-strength bolts 6 are required on the bracket side and the beam side, respectively. The standard number of rows of the high-strength bolts 6 in the beam axis direction is two or less.”, the high-strength bolts 6 on the bracket side were arranged.

As a result, as shown in FIG. 13, the maximum width of the splice plate 5 exceeded the column width of the steel frame column 2 . Also, the oblique extension c of the bracket portion 42 was 168 mm.

That is, in Structural Example 3, the high-strength bolts 6 are arranged in three rows on the bracket side in order to make the maximum width of the splice plate 5 equal to or less than the column width. By arranging the high-strength bolts 6, the maximum width of the splice plate 5 can be made wider than the column width of the steel column 2. - 特許庁

Other configurations and effects are substantially the same as those of the above-described embodiment and other examples, so description thereof will be omitted.

Although the embodiments of the present invention have been described in detail above with reference to the drawings, specific configurations are not limited to these embodiments or examples, and design modifications that do not deviate from the gist of the present invention are possible. are included in the present invention.

For example, in the above embodiments and examples, the configuration in which the steel beams 3 are connected to the four sides of the steel column 2 has been mainly described as an example, but the configuration is not limited to this, and at least one steel beam 3 is connected to the steel frame column 2, the steel frame column-to-beam connection structure 1 of the present embodiment can be provided.

1: Steel frame column beam joint structure 2: Steel frame column 3: Steel frame beam 34: Bolt hole 4: Through diaphragm 42: Bracket part 5: Splice plate 6: High strength bolt

Claims (3)

A steel column-to-beam connection structure in which a steel beam narrower than the width of the column is connected to the steel column,
a through-diaphragm having a bracket part that penetrates the inside of the steel frame column and protrudes to the outside;
a splice plate whose steel frame column side is widened and whose steel frame beam side is formed with a beam width;
a plurality of high-strength bolts for joining the steel frame column side end of the splice plate to the bracket portion and joining the steel frame beam side end of the splice plate to the steel frame beam,
A steel frame column-to-beam connection structure, wherein the required width of the through-diaphragm is defined by the following formula.
The width of the widened side of the splice plate does not yield when the steel beam yields at the bolt hole position of the high-strength bolt connection by the high-strength bolt furthest from the steel column, and the steel beam reaches full plasticity. The steel frame column-to-beam connection structure according to claim 1, characterized in that it is set so as not to break up to. The steel frame column-to-beam connection structure according to claim 1 or 2, wherein a plasticized region is formed closer to the steel frame beam than the connection point of the high-strength bolts arranged on the beam width side of the splice plate. .