JP6515302B2 - Beam joint structure design method, beam joint structure manufacturing method and beam joint structure - Google Patents

Description

The present invention relates to a method of designing a beam joint structure, a method of manufacturing a beam joint structure, and a beam joint structure.
Priority is claimed on Japanese Patent Application No. 2017-027212, filed Feb. 16, 2017, the content of which is incorporated herein by reference.

Conventionally, a joint between a beam and a large beam in a beam joint structure in which an end of a beam (a beam) is joined to a large beam (supporting member) is generally designed as a rigid connection or a pin joint (e.g. 1 to 5 and non-patent documents 1 to 2).
In a rigid joint, for example, the beamlet flange is welded or welded to the large beam (hereinafter referred to as bolt connection) and the beamlet web is bolted to a shear plate provided on the large beam. Ru. On the other hand, at a joint of a pin joint, for example, a web of a beam is bolted to a shear plate provided on a large beam, but a flange of the beam is not connected to the large beam.

When bolting a web of beamlets, the beamlets are usually friction bonded using high strength bolts. However, in this case, the treatment of the friction surfaces of the beam and the shear plate, and the torque management of tightening of the high strength bolt are required.
On the other hand, when bearing connection is carried out as bolt connection, or when bearing connection is considered and designed as bolt connection, processing of a friction surface and torque management become unnecessary.

Japanese Patent Application Laid-Open No. 2002-285642 Japan JP 2009-052302 Japanese Unexamined Patent Publication No. 2015-68005 Japan JP 2015-68001 Japanese Patent Application Laid-open No. Hei 6-280310

Nishimoto Shingo, 4 others, "Rotary stiffness and slip resistance of steel beam end with high strength bolted joints Part 1 Outline of experiment", Proceedings of Annual Conference of the Architectural Institute of Japan, September 2010, p. 703-704 Yasuda Akira, et al., "Rotary Stiffness and Slip Strength of Steel Beam-to-Beam High-Strength Bolt Joints: Part 2 Analytical Study", Proceedings of Annual Conference of the Architectural Institute of Japan, September 2010, p.705-706

However, bolts used for bearing bonding do not contribute to friction bonding. In order to ensure the transmission of force due to bearing pressure, it is desirable to determine the dimensions of the bolt and the through hole so that there is no gap between the through hole into which the bolt is inserted and the bolt. The size of the through hole needs to be larger than the diameter of the bolt in order to absorb the For this reason, the bolt moves in the through hole without the shear force being applied for the length of the gap between the through hole into which the bolt is inserted and the bolt. Even if a bending moment acts on the floor slab joined above the beam, the joint between the large beam and the beam does not have resistance to the bending moment (rotational stiffness is zero). Therefore, there is a problem that this joint does not become a rigid joint and the floor slab is easily damaged.
The same problem arises when the joint is a pin joint.

  The present invention has been made in view of the above circumstances, and a method of designing a beam connection structure capable of preventing damage to a floor slab on the beam even when supporting members and beams are pressure-bonded, and a method of manufacturing the beam connection structure And a beam joint structure.

In order to solve the above-mentioned subject, the present invention adopts the following means.
(1) A method of designing a beam joining structure according to a first aspect of the present invention includes a support member, a beam whose end is joined to the support member, a floor slab joined above the beam, and A bolt for joining the end portion and the support member in a state where the first through hole at the end portion and the second through hole of the support member are inserted into a composite through hole formed by overlapping each other ; A method of designing a beam joint structure in which a gap is present between the first through hole and the bolt and between the second through hole and the bolt in the longitudinal direction of the beam, the floor slab being bent and deformed The bolt is moved relative to the first through hole and the second through hole in the longitudinal direction of the beam, and the inner surface of the first through hole and the second through hole are acting on the floor slab until bearing capacity joined state where the bolt is in contact with the inner surface That bending moment, the to be smaller than the bending strength of the floor slab, a method of designing a beam joining structure characterized by comprising the step of setting the bending strength of the floor slab.

(2) In the aspect described in the above (1), the floor slab is a concrete slab provided on the support member, and the flexural strength of the floor slab is the compressive strength of concrete used for the floor slab. It may be calculated based on.

(3) In the aspect of the above (1) or (2), the floor slab is a reinforced concrete slab provided on the support member, and the reinforcing bars in the floor slab are straddling the support member. The bending strength of the floor slab may be calculated based on the Young's modulus and the strength of the concrete used for the floor slab and the Young's modulus and the strength of the rebar, which extend in the longitudinal direction of the beam.

(4) In the aspect described in any one of (1) to (3) above, the floor slab is formed by placing concrete on a deck plate having a plurality of grooves extending in one direction in the longitudinal direction of the beam. The groove may be arranged to extend along a direction intersecting the longitudinal direction of the beam.

(5) In the aspect described in any one of (1) to (4) above, a plurality of the synthetic through holes are provided in the end portion and the support member, and the plurality of the synthetic through holes satisfy the equation (1). In each of the synthetic through holes, the inner surface of the synthetic through hole arranged farthest from the floor slab in the vertical direction, the inner surface of the second through hole in the longitudinal direction of the beam and the bolt And the total value g _b (mm) of the gap between the bolt and the inner surface of the first through hole remote from the support member, and the rotational rigidity K _slab (N mm / rad) of the floor slab, the floor slab The bending resistance M _{slab, Rd} (N mm), the distance x _n (mm) between the neutral axis of the floor slab subjected to bending deformation and the upper surface of the floor slab, and vertical among the plurality of synthetic through holes In the direction of the floor May determine the distance x _{b1 (mm)} of the upper surface of the floor slab and the central axis of the furthest said synthetic penetrating pores rubs.

(6) In the aspect described in (5), the distance between the inner surfaces of the first through holes in the longitudinal direction of the beam is d ₀₁ (mm), and the distance between the inner surfaces of the second through holes in the longitudinal direction of the beam Distance of d ₀₂ (mm), the outer diameter of the bolt d _b (mm), the central axis of the synthetic through hole closest to the floor slab among the plurality of synthetic through holes, and the top surface of the floor slab sum the distance x _b2 (mm), the length of the beam l (mm), the beam bending rigidity _EI S ^(Nmm 2), of the floor slab mass mass and the beam of the beam to support When the weight of the beam per unit length w (N / mm) is obtained by dividing the product of the sum of the mass and the gravitational acceleration by the length of the beam, the equation (2) is satisfied. The gap g _b may be determined.

(7) A method for manufacturing a beam joint structure according to a second aspect of the present invention is a beam joint structure designed in the aspect described in any one of (1) to (6) above, And bonding the beam.

(8) A beam joining structure according to an eighth aspect of the present invention comprises: a support member; a beam whose end is joined to the support member; a floor slab joined above the beam; A bolt for joining the end portion and the support member by inserting the first through hole and the second through hole of the support member into a composite through hole formed by overlapping, and including the longitudinal length of the beam Beam joint structure in which gaps exist between the first through hole and the bolt and between the second through hole and the bolt in the direction,
A plurality of the synthetic through holes are provided in the end portion and the support member, and the second through holes in the longitudinal direction of the beam of the synthetic through holes disposed farthest from the floor slab in the vertical direction total value g _b of the clearance from the support member of the gap and the first through-hole of the far side of the inner surface and the bolt from the beam and the far side of the inner surface and the bolt _(mm), rotational stiffness K _slab of the floor slab (N mm / rad), the flexural strength M _{slab, Rd} (N mm) of the floor slab, the distance x _n (mm) between the neutral axis of the floor slab subjected to flexural deformation and the upper surface of the floor slab , and the plurality The distance x _b1 (mm) between the central axis of the synthetic through hole farthest from the floor slab and the upper surface of the floor slab in the vertical direction among the synthetic through holes of the above satisfies the formula (3).

(9) In the aspect described in the above (8), said floor slab comprises a deck plate having a plurality of grooves extending in one direction, the groove but it may also extend along a direction intersecting the longitudinal direction of the beam .

(10 ) In the aspect described in ( 9 ), the distance between the inner surfaces of the first through holes in the longitudinal direction of the beam is d ₀₁ (mm), and the distance between the inner surfaces of the second through holes in the longitudinal direction of the beam Distance of d ₀₂ (mm), the outer diameter of the bolt d _b (mm), the central axis of the synthetic through hole closest to the floor slab among the plurality of synthetic through holes, and the top surface of the floor slab sum the distance x _b2 (mm), the length of the beam l (mm), the beam bending rigidity _EI S ^(Nmm 2), of the floor slab mass mass and the beam of the beam to support When the weight g (N / mm) per unit length of the beam is divided by dividing the product of the sum of the mass and the gravitational acceleration by the length of the beam, the gap g _b is (4) You may satisfy the formula.

( 11 ) In the aspect described in any one of (8) to ( 10 ), the lower flange of the beam extending in the longitudinal direction of the beam and the support member may not be joined to each other .

  According to the above aspects of the present invention, damage to the floor slab on the beam can be prevented even when the support member and the beam are supported by pressure.

It is the perspective view which permeate | transmitted a part of building in which the beam joined structure which concerns on 1st Embodiment of this invention is used. It is the figure which carried out the side view of the principal part of the said beam joint structure, Comprising: It is sectional drawing explaining rotation of the beam after concrete hardening of a floor slab. It is the figure which carried out the side view of the principal part of the said beam joint structure, Comprising: It is sectional drawing explaining rotation of the beam before concrete hardening of a floor slab. It is sectional drawing corresponded to the III-III line in FIG. 2A. It is a figure which shows the synthetic | combination through-hole of the beam joint structure, Comprising: It is a side view explaining the state in which the bolt is inserted in the synthetic | combination through-hole arrange | positioned above the neutral axis of a floor slab. It is sectional drawing which planarly viewed the synthetic | combination through-hole in FIG. 4A from the IV-IV line. It is a figure which shows the synthetic | combination through-hole of the beam joint structure, Comprising: It is a side view explaining the state in which the volt | bolt is inserted in the synthetic | combination through-hole arrange | positioned under the neutral axis of a floor slab. It is sectional drawing which planarly viewed the synthetic | combination through-hole in FIG. 5A from the VV line | wire. It is a figure which shows the synthetic | combination through-hole of the beam joint structure, Comprising: A bolt is inserted in the synthetic | combination through-hole arrange | positioned under the neutral axis of a floor slab in the state before the bending moment by loading load acts on a floor slab. It is a side view explaining the state which is. It is sectional drawing which planarly viewed the synthetic | combination through-hole in FIG. 6A from the VI-VI line. It is a figure which shows the synthetic | combination through-hole of the beam joint structure, Comprising: A bolt is inserted in the synthetic | combination through-hole arrange | positioned under the neutral axis of a floor slab in the state after the bending moment by loading load acting on a floor slab. It is a side view explaining an operating state. It is sectional drawing which planarly viewed the synthetic | combination through-hole in FIG. 7A from the VII-VII line. It is a flowchart which shows the design method of the beam joint structure which concerns on the embodiment. It is a figure which shows the synthetic | combination through-hole of the beam joint structure which concerns on the embodiment, Comprising: It is a side view explaining the state in which the volt | bolt is inserted in the synthetic | combination through-hole arrange | positioned under the neutral axis of a floor slab. It is the sectional view which carried out the side view of the principal part of the beam joint structure in the construction process of the beam joint structure, and shows the case where the beam has shifted below to the support member. It is the figure which expanded a part of synthetic | combination through-hole of FIG. 10A. It is a figure which shows the through-hole of 2nd Embodiment of this invention, Comprising: It is a side view explaining the state in which the volt | bolt is inserted in the through-hole arrange | positioned above the neutral axis of a floor slab. It is a figure which shows the through-hole of the embodiment, Comprising: It is a side view explaining the state in which the volt | bolt is inserted in the through-hole arrange | positioned under the neutral axis of the floor slab. It is a figure which shows the through-hole of 3rd Embodiment of this invention, Comprising: It is a side view explaining the state in which the volt | bolt is inserted in the through-hole arrange | positioned under the neutral axis of a floor slab. It is the sectional view which carried out the side view of the principal part of the beam joint structure in the construction process of the beam joint structure, and shows the case where the beam has shifted below to the support member. It is the figure which expanded a part of through-hole of FIG. 13A.

First Embodiment
Hereinafter, a first embodiment of a beam joint structure according to the present invention will be described with reference to FIGS. 1 to 7B. The beam joint structure 2 according to the present embodiment is used in the building 1 shown in FIG. The building 1 includes a column 11 extending along the vertical direction, a large beam 21 extending along the horizontal plane from the column 11, a beam 31 extending along the horizontal plane from the large beam 21, a beam 21 and a beam 31 And a floor slab 41 joined to the upper side of the When the beam 31 is connected to the large beam 21 using a shear plate, the large beam 21 and the shear plate are integrally referred to as a support member.
In addition, in FIG. 1, the floor slab 41 is shown by being permeated except for a first reinforcing bar 43 described later. The large beam 21 and the small beam 31 may be inclined with respect to the horizontal plane.

In this example, the column 11 is made of CFT (Concrete Filled steel Tube). That is, in the column 11, concrete 13 is filled in the steel pipe 12. The first shear plate 14 is fixed to the steel pipe 12.
In the following, among the configurations of the building 1, the description will be given focusing on the large beam 21, the small beam 31 joined to the large beam 21, and the floor slab 41 joined to the small beam 31. The beam connection structure 2 is configured by including the large beam 21, the small beam 31, and the floor slab 41.

  As shown in FIGS. 2A to 3, for example, an H-shaped steel is used for the large beam 21. The girder 21 is disposed to extend along a horizontal plane, and has a web 22 and flanges 23 and 24. The flange 23 is located above the web 22 and the flange 24 is located below the web 22. In the following, the longitudinal direction of the large beam 21 is referred to as a first direction X, and from the large beam 21, along a horizontal plane, a second direction Y orthogonal to the first direction X, a vertical direction orthogonal to the first direction X and the second direction Y It is called 3 directions Z.

When the small beam 31 is connected to the large beam 21 using a shear plate, the second shear plate 25 is fixed to the large beam 21 by welding or the like. In this case, the girder 21 and the second shear plate 25 function as a support member. The second shear plate 25 protrudes in the second direction Y. The second shear plate 25 is formed with at least one through hole 25 a (second through hole). In FIG. 1A to FIG. 3, a plurality of through holes 25 a are formed in the second shear plate 25 along the third direction Z. Each through hole 25 a penetrates the second shear plate 25 in the first direction X. That is, the through holes 25 a are formed in a row in the second shear plate 25. The through holes 25a are not limited to one row formation. For example, it is also included in the present embodiment that the through holes 25a are arranged in two rows or in a zigzag. Further, at least one through hole 25a may be formed in one second shear plate 25, and a plurality of through holes 25a may be formed. Although four through holes 25a are provided as an example in the figure, the present invention is not limited to this. In addition, the case where a shear plate is not used is also included in the present embodiment, and in this case, the large beam 21 functions as a support member. The through hole of the large beam 21 is referred to as a through hole 25a (that is, a second through hole). In the following, in the case where the through hole 25a (the through hole 25a disposed at the uppermost position) closest to the floor slab 41 among the plurality of through holes 25a provided in the one second shear plate 25 is called the upper end through hole 25aA There is. Among the plurality of through holes 25a, the through hole 25a farthest from the floor slab 41 (the through hole 25a disposed the lowermost) may be referred to as a lower end through hole 25aB.
The end of the large beam 21 is joined to the first shear plate 14 of the column 11 by a bolt whose symbol is omitted, welding or the like.

For example, an H-shaped steel is used for the small beam 31. The beam 31 is disposed to extend along the second direction Y, and has a web 32 and flanges 33, 34. The flange 33 is located above the web 32 and the flange 34 is located below the web 32.
A plurality of studs 35 protruding upward from the flange 33 are fixed to the upper surface of the flange 33. The plurality of studs 35 are spaced apart from one another in the second direction Y.

The beam 31 is disposed so as to extend along the second direction Y in a natural state in which a bending moment due to external force or gravity does not act on the beam 31. As described later, the beam with an external force or the like acting downward bends downward. In detail, since both ends are joined to the support member, the small beam 31 is directed downward on the reference plane S parallel to the second direction Y and parallel to the vertical direction (third direction Z). It curves so as to be convex (see shape P1 in FIG. 2A). When the beam 31 is in the natural state, a plurality of bolts 36 are arranged and fixed along the third direction Z at each end of the beam 31. In this embodiment, at each end 37 of the web 32 of the beam 31 in the longitudinal direction, a through hole 32a (first through hole, see FIG. 3) of the beam 31 is formed at a position corresponding to the through hole 25a. ing. A through hole formed by overlapping the through hole 32 a (first through hole) of the beam 31 and the through hole 25 a (second through hole) of the second shear plate 25 may be referred to as a synthetic through hole 50. .
Hereinafter, among the plurality of bolts 36, those disposed above the neutral axis C3 of the small beam 31 may be referred to as bolts 36A, and those disposed below the neutral axis C3 may be referred to as bolts 36B. . The neutral axis C3 is a vertical center line of the beam 31 and is a neutral axis of the beam 31 before the concrete 44 of the floor slab 41 is hardened.

As shown in FIGS. 2A to 7B, bolt shafts 36 a of the bolts 36 are inserted into the through holes 25 a of the second shear plate 25. When the shear plate is not used, the through hole of the large beam 21 is used as the through hole 25a, and the through hole 25a of the large beam 21 and the through hole 32a of the small beam 31 are overlapped to form the synthetic through hole 50. When the beam 31 is in the natural state, the bolt shaft 36a of each bolt 36 is disposed at the position P3 (see FIGS. 4A and 5A), and is disposed coaxially with the through hole 25a of the second shear plate 25, for example. When the small beam 31 is in the natural state, the small beam is not deformed by its own weight, and when temporarily fixing the small beam 31 to the large beam 21, when the small beam 31 is lifted by a crane or the like, It means when the beam 31 is temporarily received from below. That is, in the natural state, there is a gap between each bolt 36 and the through hole 32a of the beam 31 and the through hole 25a of the second shear plate 25 so that the bending of the beam 31 by its own weight is not taken into consideration. It is.
An axis along a first direction X (a direction perpendicular to a second direction Y along the horizontal surface and along which the beam 31 extends) with respect to the beam 31 before the concrete 44 in the floor slab 41 is hardened. When it acts on the periphery, the through hole 32a of the beam 31 arranged above the neutral axis C3 is in the second direction Y (longitudinal direction of the beam 31) in a direction opposite to the beam side to which it is connected. It moves relative to the upper end through hole 25 a A of the 2 shear plate 25. The amount of movement in the second direction Y increases as the through holes 32a arranged on the upper side, the through holes 32a arranged on the uppermost side easily contact the surface of the bolt shaft 36a of the upper end bolt 36A in the second direction Y.
In addition, the external force said here means the force which acts on a structure from the outside, for example, seismic force, a wind load, an impact load, or loading load etc.
Similarly, when a bending moment due to an external force or the like acts around the axis along the first direction X with respect to the small beam 31 of the floor slab 41 before the concrete 44 hardens, the small beam arranged below the neutral axis C3. The 31 through holes 32a move relative to the lower end through holes 25aB of the second shear plate 25 toward the large beam side to which they are connected in the second direction Y (longitudinal direction of the small beams 31). The amount of movement in the second direction Y increases as the through holes 32a arranged downward, so the through holes 32a arranged the lowest tend to contact the surface of the bolt shaft 36a of the lower end bolt 36B in the second direction Y.

A nut 45 is fitted to the bolt shaft 36 a of the bolt 36. The bolt head of the bolt 36 and the nut 45 sandwich the second shear plate 25 in the first direction X. More specifically, the bolt shaft 36 a of the bolt 36 is inserted into the through hole 32 a of the beam 31 and the through hole 25 a of the second shear plate 25. The bolt head of the bolt 36 and the nut 45 fitted to the bolt 36 sandwich the web 32 of the beam 31 and the second shear plate 25 in the first direction X.
In addition, when using the bolt which carries out bearing pressure bonding generally, it is considered that a bolt and a shear plate do not carry out friction bonding (frictional force does not act between a bolt and a shear plate), and it designs. The large beam 21 and the end of the small beam 31 are joined by inserting the bolt 36 of the small beam 31 into the through hole 25 a of the second shear plate 25.

As shown in FIGS. 2A to 3, the floor slab 41 is formed by concrete 44 joined on the deck plate 42. Reinforcing bars are preferably contained in the concrete 44. For example, the floor slab 41 is manufactured by placing concrete 44 on the deck plate 42 after arranging the plurality of first reinforcing bars 43 and the second reinforcing bars not shown on the deck plate 42.
The groove 42a formed in the deck plate 42 is arranged to extend in one direction along the first direction X (direction intersecting with the longitudinal direction of the beam 31).
Referring to FIG. 1, each first reinforcing bar 43 is fixed so that the movement in the Y direction is restrained at the position of the support member, and, for example, each first reinforcing bar 43 straddles large beam 21 and the second It is preferable to extend along the direction Y and to be spaced apart from each other in the first direction X. Further, it is preferable that the respective second reinforcing bars (not shown) extend along the first direction X and be spaced apart from each other in the second direction Y.
The plurality of first reinforcements 43 and the plurality of second reinforcements are embedded in the concrete 44. The floor slab 41 is joined to the beam 31 and the beam 21.
The lower flange 34 of the beam 31 and the beam 21 (second shear plate 25) are not joined to each other. Specifically, although the beam 31 and the second shear plate 25 are joined by the bolt 36, the flange 34 of the beam 31 and the large beam 21 are not joined by the bolt 36 or welding. In this case, the width adjustment of the groove between the flange 34 and the large beam 21 and the bolt connection of the flange 34 of the small beam 31 to the large beam 21 are required when welding the flange 34 of the beam 31 to the beam 21 by welding. It is not necessary to adjust the dimensions of the base plate, which is required for the above, and it is possible to minimize the response to the dimensional error due to the construction. Furthermore, it is possible to reduce the number of welding operations and the use of bolts.

When a bending moment acts on the floor slab 41 of the beam joint structure 2 configured as described above, the small beam 31 in a natural state is curved so as to be convex downward on the reference plane S. The bending moment is a bending moment around an axis along the first direction X (a direction perpendicular to the second direction Y along the horizontal surface and along which the beam 31 extends). The neutral axis C1 is a neutral axis of the floor slab 41 after the concrete 44 of the floor slab 41 is hardened. The neutral axis of the floor slab 41 is above the flange 33 of the beam 31 in the third direction Z. An axis along a first direction X (a direction perpendicular to a second direction Y along the horizontal surface and along which the beam 31 extends) with respect to the beam 31 after the concrete 44 of the floor slab 41 is hardened. When it acts on the periphery, the through hole 32a of the beam 31 arranged below the neutral axis C1 of the floor slab 41 is connected to the large beam side to which it is connected in the second direction Y (longitudinal direction of the beam 31). It moves relative to the through hole 25 a of the 2 shear plate 25. The through holes 32a of the beam 31 arranged above the neutral axis C3 of the beam 31 move in the second direction from the direction in which the bending moment acting on the beam 31 moves before the concrete 44 of the floor slab 41 hardens. Move to the opposite side in Y. The total movement of the through holes 32a of the cross beam 31 before and after the concrete 44 of the floor slab 41 hardens relative to the through holes 25a of the second shear plate 25 is the second direction Y in the lower through holes 32a. Since the amount of movement toward the large beam side increases, the through hole 32a disposed at the lowermost position easily contacts the surface of the bolt shaft 36a of the lower end bolt 36B in the second direction Y.
In the present invention, the floor slab 41 acts when the bolt 36 contacts the inner surface of the through hole 32 a of the small beam 31 and the through hole 25 a of the second shear plate 25 in the longitudinal direction of the small beam 31. The bending moment to be produced is smaller than the bending strength of the floor slab 41 (in particular, the bending strength around the axis along the first direction X of the floor slab 41).
The bending strength of the floor slab 41 referred to here means, for example, the bending moment when the permanent deformation (non-elastic deformation) defined in the bending test occurs.

  Specifically, in the third direction Z, the moving distance in the second direction Y when the floor slab 41 is curved is longer as the through holes 32a arranged at positions farther from the neutral axis C1 of the floor slab 41. Therefore, of the plurality of through holes 32, the second direction Y (longitudinal direction of the small beam 31) of the lower end through hole 32a (the through hole 32a disposed at the lowermost position) disposed at the farthest position from the floor slab 41. The surface of the bolt shaft 36a of the bolt 36 comes in contact with the inner surface far from the girder 21 at first. After the bolt shaft 36a of the bolt 36 contacts the inner surface of the lower end through hole 32a in the second direction Y (longitudinal direction of the small beam 31) on the side far from the large beam 21, when the floor slab 41 is further curved, the through hole 32aB is a bolt 36 in the second direction Y (longitudinal direction of the small beam 31) while being in contact with the bolt shaft 36a, the second shear plate 25 is connected to the large beam side (the direction in which the small beam 31 becomes longer) It moves relatively to the lower end through hole 25aB. Eventually, the bolt shaft 36a of the bolt 36 contacts the inner surface of the through hole 25aB in the second direction Y (longitudinal direction of the beam 31) and the inner surface of the through hole 32aB and the bolt shaft 36a of the bolt 36 The bolt shaft 36a of the bolt 36 and the inner surface of the through hole 25aB come into contact with each other, and the force is transmitted from the small beam 31 to the large beam 21 along the second direction Y (longitudinal direction of the small beam 31), The bending moment acting on the beam 31 is transmitted between the end of the beam 31 and the beam 21 via the bolt 36.

Here, in the beam joint structure 2 configured as described above, before and after the bending moment due to the loading load acts on the floor slab 41, the first one is disposed below the neutral axis of the bolt 36 and the floor slab The positional relationship between the respective through holes (the synthetic through holes 50) of the 2 shear plate 25 and the beam 31 will be described with reference to FIGS. 6A to 7B.
Before the concrete 44 hardens, the bending moment due to the load does not act on the floor slab 41. At this time, as shown in FIGS. 6A and 6B, the inner surface of the through hole 32a of the small beam 31 far from the large beam 21 in the second direction Y (longitudinal direction of the small beam 31) contacts the bolt shaft 36a of the bolt 36. Do. On the other hand, the inner surface of the through hole 25 a of the second shear plate 25 is not in contact with the bolt shaft 36 a of the bolt 36.
When the concrete 44 hardens and a bending moment due to the loading load acts on the floor slab 41, the floor slab 41 bends and the floor slab bends and deforms. At this time, as shown in FIGS. 7A and 7B, the inner surface of the through hole 32a of the small beam 31 far from the large beam 21 and the through hole of the second shear plate 25 in the second direction Y (longitudinal direction of the small beam 31). The inner surface (i.e., the inner surface of the synthetic through hole 50) of the side 25a remote from the cross beam 31 contacts the bolt shaft 36a of the bolt 36, and is in a state of supporting pressure. In other words, in the second direction Y (longitudinal direction of the small beam 31), the bolt shaft 36a is sandwiched from both sides by the through holes 32a and the through holes 25a, and thus a support pressure joint is achieved.

As described above, as the bending moment acting on the floor slab 41 increases, the floor slab 41 bends, and the bolt 36 approaches the inner surface of the through hole 25 a on the side farther from the cross beam 31. At this time, in the longitudinal direction of the beam 31 (second direction Y), the inner surface of the through hole 32a of the beam 31 far from the large beam 21 and the side of the through hole 25a of the second shear plate 25 far from the beam 31 The inner diameter of the through hole 25 a and the floor slab 41 are satisfied so that the bending moment acting on the floor slab 41 when the bolt 36 contacts and bears against the inner surface is smaller than the bending strength of the floor slab 41. The bending resistance etc. of are set.
In the natural state, there are gaps between the bolts 36 and the through holes 32 a of the beam 31 and the through holes 25 a of the second shear plate 25. When the small beam 31 bends due to the weight of the small beam 31, the through hole 32 a moves, but the self-weight of the small beam 31 does not result in a state of bearing connection.
As described above, according to the beam joint structure 2 according to the present embodiment, even if a bending moment acts on the concrete slab, the floor slab can be designed so that the concrete slab is not broken by the bending moment, Damage to the floor slab can be effectively suppressed.

In the method of designing a beam joint structure and the method of manufacturing a beam joint structure according to this embodiment, the following steps are performed as illustrated in the flowchart of FIG. The following design method is preferably realized by a computer (not shown) that executes a program recorded on a non-temporary, tangible recording medium (not shown) by a CPU (not shown). In this case, it is preferable that the computer device executes the following design method in response to a command from the input device operated by the worker, and outputs the design result so as to be visible via the output device. Hereinafter, with reference to FIG. 8, a method of designing a beam joint structure will be described in detail.
First, load conditions are determined (S1). Next, structural planning is performed to temporarily determine the arrangement of columns and beams (S2). Temporary determination of the cross-sectional dimensions of the support members, beams, and floor slabs and material strength is performed (S3), and temporary determination of slab arrangement bars, arrangement of bolts, arrangement of studs, and the like is performed (S4). Next, the bending strength ( _{Mslab, Rd} ), the rotational rigidity ( _Kslab ), the clearance between the inner surface of the through hole 25a in the second direction Y and the inner surface of the through hole 25a remote from the beam 31 and the bolt shaft 36a of the bolt 36 and the through hole The total value (g _b ) of the gap between the inner surface of the large beam 21a far from the large beam 21 and the bolt shaft 36a of the bolt 36 is calculated (S5). (1) The process ends when the equation is satisfied, and when not satisfied, the design conditions of S2 to S4 are changed and recalculation is performed. The condition determined in S5 is finally output.

The value finally output in the above design method is the design value, and this design value is used in the method of manufacturing the beam joint structure. That is, by performing the above process, the size and arrangement of columns, beams and floor slabs, number of bolts, dimensions of bolts, material strength, arrangement of slabs, arrangement of studs, dimensions of through holes are output as design results. Ru. When the beam structure is manufactured, the beam joint structure 2 according to the present invention is manufactured by advancing the small beam arrangement process and the floor slab placing process using the columns, beams, and bolts according to the design result.
In detail, the worker arranges the small beam 31 so as to extend along the horizontal plane from the large beam 21 by joining the end of the small beam 31 to the large beam 21 (small beam arrangement step). At this time, the large beam 21 and the end of the small beam 31 are joined by inserting the bolt 36 fixed to the small beam 31 into the through hole 25 a formed in the second shear plate 25.
The floor slab 41 is joined (placed) above the small beam 31 (floor slab placing step).
By manufacturing the beam joint structure 2 based on the above design result, the floor when the bolt 36 contacts the inner surface of the through hole 32 a of the small beam 31 and the through hole 25 a of the second shear plate 25 The bending moment acting on the slab 41 is smaller than the bending strength of the floor slab 41.

As described above, according to the beam joining structure 2 according to the present embodiment, when the bolt 36 contacts the inner surface of the through holes 32a and 25a, the bending moment acting on the beam 31 passes through the bolt 36 and the beam 31 Is transmitted between the end of the frame and the girder 21 (second shear plate 25). In the longitudinal direction of the small beam 31, the bending moment acting on the floor slab 41 when the bolt 36 contacts and supports the inner surface of the through hole 32a of the small beam 31 and the through hole 25a of the second shear plate 25 Because the bending strength of the floor slab 41 is smaller than that of the floor slab 41, the floor slab 41 is damaged even if a bending moment acts on the floor slab 41 even before the bolts 36 contact the inner surfaces of the through holes 32a and 25a. Can be suppressed.
Furthermore, when the bolt 36 contacts the inner surface of the through holes 32a and 25a, the large beam 21 and the small beam by the bolt 36 are smaller than the bending resistance of the floor slab 41 alone than the bending resistance of the floor beam 41 alone. Because of the bending resistance of the floor slab 41, higher rigidity and strength can be exhibited than the resistance of the joint with the beam 31 alone.

Next, details of the design method of the beam joint structure 2 according to the present invention will be described with reference to FIGS. 9 to 10B and FIGS. 2A to 7B described above.
In the beam joint structure 2, the moving amount of the bolt 36 when the bending moment acts on the floor slab 41 was quantitatively examined separately in each case.

[1. Method of calculating rotational rigidity and bending strength of floor slab 41]
_Assuming that the bending stiffness of the floor slab 41 is EI _slab (N mm ² ) and the effective length of the joint between the small beam 31 and the large beam 21 (here, the second shear plate 25) is l _{j, slab} (mm), the floor slab The rotational rigidity _Kslab (N mm / rad) of 41 is obtained by the equation (11).

[1.1. Calculation example of flexural rigidity and flexural strength of floor slab 41]
The flexural rigidity EI _{slab of} the floor slab 41 and the flexural strength M _{slab, Rd} (N mm) of the floor slab 41 can be calculated, for example, in each case according to the following equation:

[1.1.1. When the floor slab 41 is a concrete slab]
When the floor slab 41 is a concrete slab having no reinforcing bars such as the first reinforcing bar 43 and the second reinforcing _bar , the bending rigidity EI _{slab of} the floor slab 41 and the bending strength M _{slab and Rd} of the floor slab 41 are It is calculated by equations (14) and (15) using equation (13). However, Young's modulus of concrete E _c (N / mm ² ), effective width of floor slab 41 b _eff (mm), effective thickness of concrete slab t _slab (mm), compressive strength of concrete f _c ( _c N / mm ² )

f _{c, t} is the tensile strength of concrete, and the approximate value by equation (12) may be used, but it may be determined by a material test or another evaluation equation. Although the method of determining the effective width b _eff of the floor slab 41 is not particularly limited, for example, as shown in FIG. 3, the pitch P between the small beams 31 adjacent in the first direction X can be the effective width b _eff . That is, the pitch P between the beamlets 31 may be equal to the effective width b _eff . Further, the effective width b _eff is, for example, British Standards "Eurocode 4: Design of composite steel and concrete structures-Part 1-1: General rules and rules for buildings" or "Various synthetic structural design guidelines and explanations", It can be decided based on the Architectural Institute of Japan, etc.
When determining the effective width b _eff of the floor slab 41, the influence of the rigidity, the number, and the like of the second reinforcing bars may be taken into consideration.

The effective thickness t _slab of the floor slab 41 is, for example, a value obtained by subtracting the depth D _p −t of the groove 42 a of the deck plate 42 from the thickness D _s (mm) of the floor slab 41 as shown in FIG. it can be a _s -D _p + t). The grooves 42 a formed in the concrete 44 by the deck plate 42 extend in the first direction X. In the concrete 44, even if a convex portion is formed between the concave portion and the concave portion, this convex portion is not effective for bending moment around an axis parallel to the first direction X. For this reason, in the concrete 44, some or all of the heights of the protrusions are not considered.
If, for example, the groove 42a formed in the concrete 44 extends along the second direction Y, the effective thickness t _slab is less than the value of (D _s −D _p + t) of the floor slab 41 it may be close to the thickness D _s.

[1.1.2. In the case where floor slab 41 is a reinforced concrete slab (cracking of concrete is not acceptable)
In this case, the concrete maintains a tensile force. The flexural rigidity EI _slab of the floor slab 41 is calculated by equation (18) using equations (16) and (17).
However, the Young's modulus of the reinforcing bar (steel) is E _S (N / mm ² ), the effective sectional area of the first reinforcing bar 43 is a _r (mm ² ), the upper surface 41 a of the floor slab 41 and the central axis of the first reinforcing bar 43 A distance of D _r (see FIG. 2A) (mm), a Young's modulus ratio which is a ratio of a Young's modulus E _S of a reinforcing bar to a Young's modulus E _c of concrete is n _E.
For example, when a plurality of first reinforcing bars 43 are disposed within the effective width b _eff of the floor slab 41, the effective sectional area a _r of the first reinforcing bars 43 is the sectional area of the plurality of first reinforcing bars 43 And the sum of

The bending strength _{Mslab, Rd} of the floor slab 41 is calculated by equation (20) using equations (12) and (19).

[1.1.3. In the case where floor slab 41 is a reinforced concrete slab (cracks in concrete are acceptable)
In this case, the flexural rigidity EI _slab of the floor slab 41 is calculated by the equation (24) using the equations (21) to (23).

The bending resistance M _{slab, Rd} of the floor slab 41 is calculated by equation (27) using equations (25) and (26).
However, let f _sd (N / mm ² ) be the yield stress or tensile strength of the rebar. The function min (A, B) means the smaller value of A and B (however, the value of A when A and B are the same value).

As explained above, according to the beam joint structure 2 according to the present embodiment, when the floor slab is a concrete slab without rebar, even if a bending moment acts on the concrete slab, the concrete slab is cracked by the bending moment The floor slab can be designed so as not to damage the floor slab effectively.
In addition, it is possible to evaluate the bending strength of the floor slab when the floor slab is a concrete slab having reinforcing bars, and to effectively prevent the floor slab from being damaged.
Furthermore, by crossing the groove direction of the deck plate extending in one direction with the longitudinal direction of the beam, load and bending acting in the cross section intersecting the groove extending direction of the deck plate as compared with the case without the groove of the deck plate The strength for the moment can be increased.

[1.2. Calculation example of effective length l _{j, slab} of joint]
The effective length l _{j, slab} of the joint is, for example, the distance from the end of the flange 23 of the large beam 21 to the stud 35 a closest to the large beam 21 among the studs 35 provided on the small beam 31 in the second direction Y (See FIG. 2A). Alternatively, the effective length l _{j, slab} of the joint may be a distance from the central axis of the web 22 of the girder 21 to the central axis of the bolt row of the bolts 36 in the second direction Y. In this example, as shown in FIG. 2A, the distance from the end of the flange 23 to the stud 35a closest to the large beam 21 is calculated as the effective length l _{j, slab} .

[2. Derivation of a conditional expression that the bolt 36 contacts the inner surface of the through hole 25a]
[2.1. When a gap before the bending moment acts on the floor slab 41 is g _b
The gap between the inner surface of the through hole 25a in the second direction Y and the side remote from the small beam 31 of the through hole 25a in the second direction Y before the bending moment acts on the floor slab 41 and the bolt shaft 36a of the bolt 36 The total value of the gap between the inner surface of the bolt 36 and the bolt shaft 36 a of the bolt 36 is denoted by g _b (mm). When a bending moment acts on the floor slab 41, the floor slab 41 and the beam 31 bend and curve so as to be convex downward. At this time, in the longitudinal direction of the beam 31, the bolt shaft 36a of the bolt 36 contacts the inner surface of the through hole 32a and the lower end through hole 25aB. Further, depending on the conditions, in the longitudinal direction of the beam 31, the bolt shaft 36a of the bolt 36 contacts the inner surface of the through hole 32a and the upper end through hole 25aA.
When a load such as a load is applied and the floor slab 41 is subjected to bending deformation, the rotation angle of the end portion of the beam 31 which bends and deforms with the floor slab 41 is set as θ _j (rad (radian)). The rotation angle θ _j is a rotation angle around an axis along the first direction X. The condition for the bolt shaft 36a of the bolt 36 to contact the inner surface of the lower end through hole 25aB is the equation (31). However, as shown in FIG. 2A, the distance between the central axis of the lower end through hole 25aB and the upper surface 41a of the floor slab 41 is x _b1 (mm), and the distance between the neutral axis C1 of the floor slab 41 and the upper surface 41a of the floor slab 41 And x _n (mm).

Assuming that the rotation angle when an equal sign is established in equation (31) is θ _{j, t} (rad), the rotation angle θ _{j, t} is calculated by equation (32).

On the other hand, the condition that the magnitude of the bending moment does not exceed the bending resistance M _{slab, Rd} of the floor slab 41 until the bolt shaft 36 a of the bolt 36 contacts the inner surface of the lower end through hole 25 aB is equation (33). However, let the bending moment generated in the floor slab 41 when the rotation angle of the end of the beam 31 be θ _{j, t be} M _{slab, t} (N mm).

  Substituting equation (32) into equation (33) and rearranging, equation (34) is obtained.

As described above, according to the beam joint structure 2 according to the present embodiment, among the plurality of synthetic through holes (the through hole 32a and the lower end through hole 25aB) along the neutral axis of the floor slab and the vertical direction, the vertical Consider the gap with the bolt in the longitudinal direction of the composite through hole beam farthest from the floor slab in the direction. As a result, the conditions under which the bending moment is transmitted between the end of the beam and the support member via the bolt can be quantitatively evaluated, and damage to the floor slab can be effectively suppressed.

[2.2. When the gap g _b is determined in consideration of the rotation angle of the end of the beam 31 before the floor slab 41 is hardened]
The beam 31 and the floor slab 41 are constructed, for example, by the following process.
(1) Temporarily fasten the end of the girder 31 to the girder 21 with a bolt 36.
(2) Join the deck plate 42 above the beam 31.
(3) The first reinforcing bar 43 and the second reinforcing bar are arranged on the beam 31 via a spacer (not shown).
(4) The concrete before hardening is placed on the deck plate 42.
(5) The concrete is hardened to obtain hardened concrete 44. Thus, the floor slab 41 is formed on the beam 31.

In the steps (1) to (4), the gravity acting on the beam 31 is supported only by the beam 31. Then, only when the concrete is hardened by performing the step (5), it is integrated with the small beam 31 and the concrete 44 to become a synthetic beam. The beam 31 acting as a composite beam and the gravity acting on the floor slab 41 are supported by the beam 31 and the floor slab 41.
Therefore, before the beam 31 and the floor slab 41 become a composite beam, the gravity or the like acts on the beam 31 to rotate the end of the beam 31.

Here, it is assumed that the small beam 31 before becoming a composite beam is supported at both ends by pin joints (pin bearings). The length of the small beam 31 is l (mm), the sum of the mass of the small beam 31 and the mass of the floor slab 41 supported by the small beam 31 is obtained, and the product of the calculated mass and the gravitational acceleration is the length of the small beam 31 W (N / mm), the distance between the inner surfaces of the through holes 32a in the second direction Y, and d ₀₁ in the second direction Y The distance between the inner surfaces of the through holes 25a is d ₀₂ (mm), the outer diameter of the bolt shaft 36a of the bolt 36 is d _b (mm), and the distance between the central axis of the upper end through holes 25aA and the upper surface 41a of the floor slab 41 is x _b2 (mm), the flexural rigidity of the beams 31 and _EI S (Nmm ^2).
For example, when the mass of the small beam 31 is 0.02 (kg) per 1 (mm), the mass of the small beam 31 converted to the load per unit length of the small beam 31 is (0.02 It becomes 0.196 (N / mm) from the formula of 9.8 9.8).
In this way, it is assumed that an equally distributed load acts on the beam 31.

A clearance between the inner surface of the through hole 25a in the second direction Y and the inner surface of the through hole 25a remote from the beam 31 and the bolt shaft 36a of the bolt 36 and a clearance between the inner surface of the through hole 32a remote from the large beam 21 and the bolt shaft 36a of the bolt 36 The total value g _b (mm) of is calculated by equation (35) (see FIG. 4A). When viewed in the first direction X, the through holes 25a and the bolt shafts 36a are circular. The gap g _b (mm) is the maximum value of the gap that can occur between the through hole 25 a and the bolt shaft 36 a.

Before the bending moment acts on the floor slab 41, when the beam 31 is bent by the gravity acting on itself, the end of the beam 31 is the rotation angle θ _j, calculated from the equation (36) ₀ (rad) rotate.
The distance between the lowermost bolt 36 and the neutral axis C3 of the beam 31 is the value of the equation {(x _b1 −x _b2 ) / 2}. For this reason, the through holes 32a of the beam 31 disposed at the lowermost position are closer to the beam 21 in the second direction Y than the lower end through holes 25aB (in a direction in which the beam 31 becomes longer). It moves by Δg (mm) obtained from the equation (37) (see FIG. 9).

Although Δg is determined based on a value obtained by converting the mass of the small beam 31 into a load per unit length of the small beam 31, the mass of the small beam 31 and the mass of the floor slab 41 before the concrete is hardened are determined. The value of Δg may be determined by setting the value converted to the load per unit length of the beam 31 as w. In this case, Δg becomes large.
The bolt 36 disposed at the uppermost position may move Δg (mm) inward in the second direction Y with respect to the upper end through hole 25aA.
Thereby, before the bending moment acts on the floor slab 41, when the beam 31 is bent by its own weight, the inner surface of the through hole 25a in the second direction Y and the bolt 36 on the side far from the beam 31 The total value g _b (mm, see FIG. 9) of the gap between the bolt shaft 36a and the gap between the inner surface of the through hole 32a far from the large beam 21 and the bolt shaft 36a of the bolt 36 is calculated by equation (38) .

Furthermore, when the small beam 31 is temporarily fixed with the bolt 36 in the above-described process of installing the small beam 31 and the floor slab 41, as shown in FIG. 10B, the through hole 25a and the small beam provided in the second shear plate 25. The through holes 32a (see also FIG. 3) provided in the web 32 of 31 are displaced downward by the value of the equation (d ₀ −d _b ) by the weight of the beam 31. 10B is an enlarged view of a part of the synthetic through hole of FIG. 10A.
The gap g _b ′ in the second direction Y at this time is smaller than the gap g _b calculated by the equation (38). Therefore, by setting the bending strength of the floor slab 41 so as to satisfy to the (34) with a gap g _b calculated in equation (38), the safe side of the design.

When the plurality of through holes 25a (bolts 36) are provided at a constant pitch, the vertical pitch of the plurality of through holes 25a is p _v (mm), the number of the plurality of through holes 25a (a plurality of bolts 36) Assuming that the number n is n, equation (39) holds. Substituting equation (39) into equation (38) yields equation (40).

As described above, according to the beam joining structure 2 according to the present embodiment, before the floor slab on the beam hardens, the bent state of the beam due to the gravity acting on the beam is considered. For this reason, the gap between the synthetic through hole (the through hole 32a and the lower end through hole 25aB) in the longitudinal direction of the beam and the bolt can be quantitatively evaluated, and damage to the floor slab can be more effectively suppressed.

〔Example〕
Hereinafter, Examples and Comparative Examples of the present invention will be specifically shown and described in more detail, but the present invention is not limited to the following Examples.
In all the following examples and comparative examples, dimensions, physical property values and the like are as follows.
Young's modulus of the reinforcing bars _{E S} is ^{205000 (N / mm 2),} ( see FIG. 2A) plate thickness t of the deck plate is 1.2 (mm), the Young's modulus of the concrete _{E c} is 14000 (N / ^mm 2), the floor Slab thickness D _s is 190 (mm), floor slab effective width b _eff is 2000 (mm), distance between first rebars (pitch) p _R is 100 (mm), upper surface of floor slab and first rebar the distance _{D r} between the center axis 25 (mm), the length l of the beam 10400 (mm), the flexural rigidity of the beam EI _S is ^{76875 × 10 9 (Nmm 2)} , an inside diameter _{d 01} and the through hole of the through hole 32a The inner diameter d ₀₂ of 25 a is 26 (mm), the outer diameter d _{b of the} bolt is 24 (mm), and the mass w of the beam converted to the load per unit length of the beam is 30 (N / mm).

Thereby, Young's modulus ratio n _E which is a ratio of Young's modulus E _S of reinforcing bars to Young's modulus E _c of concrete becomes 14.64. The number n _{R of} first rebars is 19 according to the equation (b _eff / p _R −1).

[1. When the floor slab is a concrete slab (without rebar)
Table 1 shows an example of the dimensions and physical property values, etc. of the comparative example and the examples 1 to 3. In this case, even if a bending moment acts on the concrete slab, the floor slab is designed such that the bending moment does not break the concrete slab. Therefore, the tensile strength of the concrete determines whether the concrete slab is damaged or not.

In the comparative example, the compressive strength f _{c of} concrete is 40 (N / mm ² ). Using the compressive strength f _{c of} concrete, the value of the tensile strength f _{c, t} (N / mm ² ) can be obtained from the equation (12). The height D _p of the convex portion of the deck plate is 50 (mm). For the first rebar, the yield stress or tensile strength f _sd is 400 (N / mm ² ), and the outer diameter D _R (mm) is 16 (mm). In this case, the effective cross-sectional area _a r a first reinforcing bar (mm ²⁾ is calculated to be ^{_{(πn R D R 2/4}} ) 3820 from the formula of (mm ^2). Here, π is the circle ratio.
The rebar ratio will be described later.
When the floor slab is a concrete slab, the floor slab does not have the first rebar. However, the values for the first reinforcing bar were determined for the other cases described later.

The distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 620 (mm) and the distance x _b2 between the central axis of the upper end through hole and the upper surface of the floor slab is 260 (mm) The rotation angle θ _{j, 0} generated at the end of the beam when the beam is deflected by gravity acting on itself is 0.0183 (rad), and the second penetration in the beam length direction total value g _b of the gap from the support member of the gap and the first through-hole of the far side of the inner surface and the bolt from the beams and the far side of the inner surface and bolt holes is 0.7 (mm).

The effective thickness t _slab of the concrete _slab is calculated to be 141.2 (mm) from the equation (D _s −D _p + t). As described above, the effective thickness t _slab may be calculated from the equation (D _s −D _p ).
Reinforcement ratio described _above, the equation of _{{a r / (b eff ·} (t slab -D r))}, is calculated to be 0.64 (%). The distance x _n between the neutral axis of the floor slab and the top surface of the floor slab is calculated to be 70.6 (mm) according to the equation (t _slab / 2).

Flexural rigidity _{EI slab} of the floor slabs _is calculated as ^{_{{(b eff t slab 3/}} 12) · E c / 10 9} 6569 the equation of (kNm ^2). Using the effective width b _eff of the floor slab and the effective thickness t _slab of the concrete slab, the value of the section modulus Z _c of the floor slab can be obtained as 6645813 (mm ³ ) from the equation (13).
The flexural strength M _{slab, Rd} of the floor slab can be calculated as 23.5 (kNm) according to equation (15).
Although not shown in Table 1, the variable φ ₁ is the curvature of the floor slab, which is calculated as 3.58 × 10 ⁻⁶ (mm ⁻¹ ) from the formula of (M _{slab, Rd} / EI _slab / 10 ³ ).
The effective length l _{j, slab} of the joint is 200 (mm).
Although not shown in Table 1, the rotation angle φ ₂ is calculated to be 0.0007 (rad) from the equation (φ ₁ · l _{j, slab} ).

The rotational stiffness K _slab of the floor _slab is calculated as 32844 (kNm / rad) according to the formula {EI _slab / (l _{j, slab} / 10 ³ )}.
Bending Strength _{M slab} for rotational stiffness _{K slab} in the floor _slab, the ratio of the _Rd (hereinafter referred to as bending strength _ratio), from formula _{(M slab, Rd / K slab} ), is calculated to be 0.00072.
The ratio of the gap g _b to the difference between the distance x _b1 and the distance x _n (hereinafter referred to as the gap ratio) is calculated as 0.00129 from the equation {g _b / (x _b1 −x _n )}.

The above-mentioned equation (34) can be reworded as a condition in which the bending resistance ratio is equal to or higher than the gap ratio. That is, the embodiment becomes an example when the bending resistance ratio is equal to or more than the gap ratio, and the comparison example becomes when the bending resistance ratio is smaller than the gap ratio.
In the comparative example in Table 1, the bending moment of the floor slab acting on the floor slab when the bending strength ratio is smaller than the gap ratio and the bolt contacts the inner surface of the through hole and carries out pressure bonding is more than the bending strength of the floor slab It was also found to be large.

In the beam joint structure of Example 1, in the beam joint structure of the comparative example, the compressive strength f _{c of} concrete is 100 (N / mm ² ), and the effective length l _j of the joint is 250 (mm). By changing the compressive strength f _c and the effective length l _{j, slab} , values from the value of the tensile strength f _{c, t} to the bending resistance ratio and the gap ratio are calculated in the same manner as described above.
In the beam joint structure of the first embodiment, the bending strength ratio is equal to or higher than the gap ratio, and the bending moment of the floor slab acting on the floor slab when the bolt contacts the inner surface of the through hole It was found to be smaller than the bending resistance.

Beam junction structure of Example 2, the beams joining structure of the comparative example, the height D _p of the convex portion of the deck plate was 120 (mm). The beam joining structure of the third embodiment is the beam joining structure of the comparative example, in which the distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 640 (mm), and the central axis of the upper through hole and the upper surface of the floor slab And the distance x _b2 between them was 240 (mm).

  Also in the beam joint structures of Example 2 and Example 3, the bending moment of the floor slab acting on the floor slab when the bending strength ratio is equal to or higher than the gap ratio and the bolt contacts the inner surface of the through hole But it was found to be smaller than the flexural strength of the floor slab.

[2. When the floor slab is a reinforced concrete slab (concrete cracking is not acceptable)
Table 2 shows an example of the dimensions, physical property values and the like of the comparative example and the example 1 to the example 3. In this case, as in the case where the floor slab is a concrete slab, the floor slab is designed such that even if a bending moment acts on the floor slab, the bending moment does not break the concrete of the floor slab.

In the comparative example, the compressive strength f _{c of the} concrete is 40 (N / mm ² ), and the height D _p of the convex portion of the deck plate is 50 (mm). For the first rebar, the yield stress or tensile strength f _sd is 400 (N / mm ² ), and the outer diameter D _R is 10 (mm).
The distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 620 (mm) and the distance x _b2 between the central axis of the upper end through hole and the upper surface of the floor slab is 260 (mm) The rotation angle θ _{j, 0} generated at the end of the beam when the beam is deflected by gravity acting on itself is 0.0183 (rad), and the second penetration in the beam length direction total value g _b of the gap from the support member of the gap and the first through-hole of the far side of the inner surface and the bolt from the beams and the far side of the inner surface and bolt holes is 0.7 (mm). The effective length l _{j, slab} of the joint is 200 (mm).
By changing the compressive strength f _{c of the} concrete, the height D _p of the convex part of the deck plate, the outer diameter D _R of the first reinforcing bar, etc. _, the value from the tensile strength f _{c, t} to the bending strength ratio and the gap ratio Values are calculated as above.

In this case, the distance x _n between the neutral axis of the floor slab and the upper surface of the floor slab is calculated to be 67.3 (mm) according to equation (16). Second moment _{I Uncracked} is calculated as (17) than 34,922,635 (mm ^4). The flexural rigidity EI _slab of the floor _slab is calculated as 7159 (kNm ² ) according to equation (18).
From the equation (19) _, the value of the cross section coefficient Zc _{, r} of the floor slab can be obtained as 7595494 (mm ³ ) using the second moment of area I _uncracked , Young's modulus ratio n _E and distance x _n . The flexural strength M _{slab, Rd} of the floor slab is calculated to be 26.90 (kNm) according to equation (20).

  In the beam connection structure of the comparative example, the bending strength ratio (0.00075) is smaller than the gap ratio (0.00128), and the bending strength of the floor slab is when the bolt contacts the inner surface of the through hole and carries out pressure bonding It has been found that the bending moment of the floor slab acting on the floor slab of is larger than that of the floor slab.

In the beam joint structure of Example 1, in the beam joint structure of the comparative example, the height D _p of the convex portion of the deck plate is 100 (mm), and the outer diameter D _R of the first reinforcing bar is 16 (mm). The beam joining structure of Example 2 is the beam joining structure of the comparative example, in which the distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 640 (mm), and the central axis of the upper through hole and the upper surface of the floor slab And the distance x _b2 between them was 240 (mm). The beam joining structure of Example 3 is the beam joining structure of the comparative example, and the compressive strength f _{c of} concrete is 60 (N / mm ² ), the outer diameter D _R of the first reinforcing bar is 16 (mm), and the lower end through hole Distance x _b1 between center axis and top surface of floor slab 630 mm, distance x _b2 between center axis of top through hole and top surface of floor slab 250 mm, effective length of joint l _{j, slab} Was set to 190 (mm).
In the beam joint structure of Examples 1 to 3, the bending strength ratio is equal to or higher than the gap ratio, and the bending moment of the floor slab acting on the floor slab when the bolt contacts the inner surface of the through hole and performs bearing connection , It was found that it is smaller than the bending strength of the floor slab.

[3. When the floor slab is a reinforced concrete slab (cracks in concrete are acceptable)
Table 3 shows an example of the dimensions, physical properties and the like of the comparative example and the examples 1 to 3. In this case, it is also assumed that when a bending moment acts on the floor slab, the concrete in the floor slab is cracked due to the bending moment.

In the comparative example, the compressive strength f _{c of the} concrete is 40 (N / mm ² ), and the height D _p of the convex portion of the deck plate is 50 (mm). For the first rebar, the yield stress or tensile strength f _sd is 400 (N / mm ² ), and the outer diameter D _R is 10 (mm).
The distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 580 (mm), and the distance x _b2 between the central axis of the upper end through hole and the upper surface of the floor slab is 300 (mm) The rotation angle θ _{j, 0} generated at the end of the beam when the beam is deflected by gravity acting on itself is 0.0183 (rad), and the second penetration in the beam length direction total value g _b of the gap from the support member of the gap and the first through-hole of the far side of the inner surface and the bolt from the beams and the far side of the inner surface and bolt holes is 1.4 (mm). The effective length l _{j, slab} of the joint is 100 (mm).
By changing the outer diameter D _R of the first rebar, yield stress or tensile strength f _sd , height D _p of the convex part, etc. _, the value from the value of tensile strength f _{c, t to} the ratio of bending strength and gap ratio Is calculated in the same manner as above.

However, in this case, using the effective cross-sectional area a _r of the first rebar, the effective width b _eff of the floor slab, the Young's modulus ratio n _E , and the effective thickness t _slab of the concrete slab, equivalent rebar The value of the ratio p _s is determined to be 0.077. The distance x _n between the neutral axis of the floor slab and the upper surface of the floor slab is calculated to be 100.6 (mm) according to equation (22). The geometrical moment of inertia I _cracked is calculated as 11575694 (mm ⁴ ) from the equation (23). The flexural rigidity EI _slab of the floor slab 41 is calculated to be 2373 (kNm ² ) according to equation (24). Distance x _n , distance D _r between top surface 41 a of floor slab 41 and central axis of first reinforcing bar 43, effective thickness t _{slab of} concrete slab, effective width b _{eff of} floor slab, compressive strength f _{c of} concrete, rebar Using the yield stress or tensile strength f _sd and the effective cross-sectional area a _r of the first rebar _, the value of the flexural strength M _c, R _{d of the} floor slab determined by the concrete according to equation (25) is 166.9 (kNm) From the equation (26), the flexural strength M _{r, R d of the} floor slab determined by the reinforcing bar is determined to be 61.3 (kNm).
The flexural strength M _{slab, Rd} of the floor slab is calculated to be 61.3 (kNm) according to equation (27).

  In the beam joint structure of the comparative example, the floor which acts on the floor slab when the bending strength ratio (0.0026) is smaller than the gap ratio (0.0030) and the bolt contacts the inner surface of the through hole and performs pressure bonding It was found that the bending moment of the slab was greater than the bending capacity of the floor slab.

The beam joint structure of Example 1 has an outer diameter D _R of the first reinforcing bar of 16 (mm) in the beam joint structure of the comparative example. In the beam joint structure of Example 2, in the beam joint structure of the comparative example, the yield stress or tensile strength f _sd of the first reinforcing _bar is 500 (N / mm ² ). Beam junction structure of Example 3, the beam joining structure of the comparative example, the height D _p of the convex portion of the deck plate was 70 (mm).
In the beam joint structure of Examples 1 to 3, the bending strength ratio is equal to or higher than the gap ratio, and the bending moment of the floor slab acting on the floor slab when the bolt contacts the inner surface of the through hole and performs bearing connection , It was found that it is smaller than the bending strength of the floor slab.

As described above, according to the beam joining method of the beam joining structure 2 according to the present embodiment, the manufacturing method of the beam joining structure 2 and the beam joining structure 2, the bending strength M _{slab, Rd of} the floor _slab 41 and the floor slab 41 of rotational stiffness _{K slab,} the through hole 25a and the bolt gap _{g b} of the bolt shaft 36a of 36, the lower end through the central axis of the hole 25aB and the distance x _b1 of the upper surface 41a of the floor slab 41, and the neutral axis of the floor slab 41 The distance x _n between C 1 and the upper surface 41 a of the floor slab 41 satisfies the equation (34). Thereby, the state where the bending moment is transmitted between the end of the small beam 31 and the large beam 21 via the bolt 36 is quantitatively evaluated to effectively suppress the floor slab 41 from being damaged. it can.
Also, consider using the value of the gap g _b (38) where the deflected state the joists 31 by the gravity acting on the joists 31 before the floor slab 41 is cured on the joists 31 in, the gap g _b of the bolt shaft 36a of the through hole 25a and the bolt 36 quantitatively evaluated, the floor slab 41 can be more effectively prevented from being damaged.

As mentioned above, although 1st Embodiment of this invention was explained in full detail with reference to drawings, a specific structure is not limited to this embodiment. Modifications, combinations, deletions and the like of configurations can be made without departing from the scope of the present invention. Furthermore, it goes without saying that each of the configurations shown in each embodiment can be used in combination as appropriate.
For example, in the first embodiment, the through hole 25 a is formed in the second shear plate 25 of the large beam 21, and the bolt 36 is fixed to the small beam 31. However, the bolt 36 may be fixed to the large beam 21 and a through hole may be formed in the small beam 31.
Although the through holes 25 a may be formed in the second shear plate 25 which is a component of the large beam 21, the through holes may be formed in the web 22 and the flanges 23, 24 of the large beam 21.
The supporting member is the large beam 21, and the beam is the small beam 31. However, the support member may be a column and the beam may be a large beam.

  So far, the support member and the synthetic through-hole formed in the beam have been described, but the through-hole in the shear plate and the through-hole in the small beam have the same dimensions, and a bending moment due to external force or gravity acts on the small beam. In the case of a natural state where there is no natural condition, it is assumed that the through hole of the shear plate and the through hole of the girder are at the same position in a plane orthogonal to the central axis of the bolt. The form will be described below.

Second Embodiment
Hereinafter, a second embodiment of a beam joint structure according to the present invention will be described with reference to FIGS. 1 to 3 and FIGS. 11A to 11B. The beam joint structure 2 of this embodiment is used for the building 1 shown in FIG. The building 1 includes a column 11 extending along the vertical direction, a large beam (supporting member) 21 extending along the horizontal plane from the column 11, a beam 31 extending along the horizontal plane from the large beam 21, and a large beam 21 And a floor slab 41 joined to the upper side of the beam 31.
In addition, in FIG. 1, the floor slab 41 is shown by being permeated except for a first reinforcing bar 43 described later. The large beam 21 and the small beam 31 may be inclined with respect to the horizontal plane.

In this example, the column 11 is made of CFT (Concrete Filled steel Tube). That is, the column 11 is configured such that the concrete 13 is surrounded by the steel pipe 12. The first shear plate 14 is fixed to the steel pipe 12.
In the following, among the configurations of the building 1, the description will be given focusing on the large beam 21, the small beam 31 joined to the large beam 21, and the floor slab 41 joined to the small beam 31. The beam connection structure 2 is configured by including the large beam 21, the small beam 31, and the floor slab 41.

  As shown in FIGS. 2A to 3, for example, an H-shaped steel is used for the large beam 21. The large beam 21 is disposed so that the flanges 23 and 24 are located above and below the web 22 and extend along the horizontal surface. Hereinafter, the longitudinal direction of the large beam 21 is referred to as a first direction X.

The second shear plate 25 is fixed to the large beam 21 by welding or the like. The second shear plate 25 protrudes from the large beam 21 in a second direction Y that is along the horizontal surface and orthogonal to the first direction X. A plurality of through holes 25 a are formed in the second shear plate 25 so as to be aligned in the vertical direction. Each through hole 25 a penetrates the second shear plate 25 in the first direction X. That is, through holes 25 a are formed in a line in the second shear plate 25. Below, the through-hole 25a closest to the floor slab 41 (through-hole 25a arrange | positioned at the highest) among several through-holes 25a may be called upper end through-hole 25aA. Among the plurality of through holes 25a, the through hole 25a farthest from the floor slab 41 (the through hole 25a disposed the lowermost) may be referred to as a lower end through hole 25aB.
The end of the large beam 21 is joined to the first shear plate 14 of the column 11 by a bolt whose symbol is omitted, welding or the like.

For example, an H-shaped steel is used for the small beam 31. The small beam 31 is disposed so that the flange 33 and the flange 34 are located above and below the web 32, respectively, and extend along the second direction Y.
A plurality of studs 35 protruding upward from the flange 33 are fixed to the upper surface of the flange 33. The plurality of studs 35 are spaced apart from one another in the second direction Y.

The beam 31 is disposed so as to extend along the second direction Y in a natural state in which a bending moment due to external force or gravity does not act on the beam 31. As described later, when an external force or the like acts downward on the small beam 31, the small beam 31 becomes downwardly convex on the reference plane S parallel to the second direction Y and parallel to the vertical direction. As curved (see shape P1 in FIG. 2A). When the beam 31 is in a natural state, a plurality of bearing bolts 36 are aligned and fixed in the vertical direction at each end of the beam 31. In the present embodiment, at each end of the web 32 of the beam 31, through holes 32 a (see FIG. 3) are formed at positions corresponding to the through holes 25 a.
Hereinafter, among the plurality of bearing bolts 36, the one disposed above the neutral axis C3 of the small beam 31 is referred to as a bearing bolt 36A, and the one disposed below the neutral axis C3 is the bearing bolt. It may be called 36B. The neutral axis C3 is the center line of the beam 31 in the vertical direction.

As shown in FIGS. 2A to 2B and FIGS. 11A to 11B, the bolt shafts 36 a of the bearing bolts 36 are inserted into the through holes 25 a of the second shear plate 25. For example, when the beam 31 is in a natural state, the bolt shafts 36a of the bearing bolts 36 are disposed at the position P3 and coaxially with the through holes 25a of the second shear plate 25. When the beam 31 is in a natural state, it means that the beam 31 is lifted by a crane or the like when temporarily securing the beam 31 to the beam 21 as described later.
When a bending moment due to an external force or the like acts on the small beam 31 before the concrete 44 in the floor slab 41 is hardened, the bearing bolt 36A disposed above the neutral axis C3 is from the large beam 21 in the second direction Y It moves in the direction of separation (the direction in which the length of the small beam 31 becomes short). The amount of movement in the second direction Y increases as the pressure receiving bolt 36A disposed above increases, so the bolt shaft 36a of the pressure receiving bolt 36A disposed at the top most easily contacts the inner surface of the upper end through hole 25aA.
Similarly, the bearing bolt 36B disposed below the neutral axis C3 moves in a direction approaching the large beam 21 in the second direction Y (a direction in which the length of the small beam 31 becomes longer). The amount of movement in the second direction Y increases as the pressure receiving bolt 36B is disposed lower, so the bolt shaft 36a of the pressure receiving bolt 36B disposed at the lowermost position easily contacts the inner surface of the lower end through hole 25aB.

Although not shown, a nut is fitted to the bolt shaft 36 a of the bearing bolt 36. The bolt head of the bearing bolt 36 and the nut sandwich the second shear plate 25 in the first direction X. More specifically, the bolt shafts 36 a of the bearing bolts 36 are respectively inserted into the through holes 32 a of the beam 31 and the through holes 25 a of the second shear plate 25. The bolt head of the bearing bolt 36 and the nut fitted to the bearing bolt 36 sandwich the web 32 of the beam 31 and the second shear plate 25 in the first direction X.
In general, when using a bearing bolt, the bearing bolt and the shear plate are designed not to be frictionally bonded (no frictional force acts between the bearing bolt and the shear plate).
The large beam 21 and the end of the small beam 31 are joined by inserting the bearing bolt 36 of the small beam 31 into the through hole 25 a of the second shear plate 25.

As shown in FIGS. 2A to 3, for example, the floor slab 41 places concrete 44 on the deck plate 42 after arranging the plurality of first reinforcing bars 43 and the second reinforcing bars not shown on the deck plate 42. Manufactured by
The deck plate 42 is arranged such that the recess 42 a formed in the deck plate 42 extends in the first direction X.
The first reinforcing bars 43 extend along the second direction Y and are spaced apart from each other in the first direction X. On the other hand, while each 2nd reinforcement extends along the 1st direction X, it mutually spaces apart in the 2nd direction Y, and is arrange | positioned.
The plurality of first reinforcements 43 and the plurality of second reinforcements are embedded in the concrete 44. The floor slab 41 is joined to the beam 31 and the beam 21.

When a bending moment acts on the floor slab 41 of the beam joint structure 2 configured as described above, the small beam 31 in a natural state is curved so as to be convex downward on the reference plane S. The bending moment is a bending moment around an axis along the first direction X (a direction perpendicular to the second direction Y along the horizontal surface and along which the beam 31 extends).
The bending strength of the floor slab 41 (in particular, the bending strength around the axis along the first direction X of the floor slab 41) is determined by the bending moment acting on the floor slab 41 and the bolt shaft of the bearing bolt 36 on the inner surface of the through hole 25a. It is equal to or greater than the magnitude of bending moment when 36a contacts.
The bending strength of the floor slab 41 referred to here means, for example, the bending moment when the permanent deformation (non-elastic deformation) defined in the bending test occurs.

  Specifically, in the third direction Z, the moving distance in the second direction Y when the small beam 31 is curved by about the pressure receiving bolt 36 disposed at a position separated from the neutral axis C1 of the floor slab 41. Is long. Therefore, among the plurality of through holes 25a, the bolt shaft 36a of the bearing bolt 36 is provided on the inner surface of the lower end through hole 25aB (the lowermost through hole 25a) disposed at the farthest position from the floor slab 41. Get in touch first. When the bolt shaft 36 a of the bearing bolt 36 contacts the inner surface of the through hole 25 a, the bending moment acting on the beam 31 is transmitted between the end of the beam 31 and the beam 21 via the bearing bolt 36.

As the bending moment acting on the floor slab 41 increases, the floor slab 41 bends, and the bearing bolt 36 approaches the inner surface of the through hole 25a. At this time, the inner diameter of the through hole 25a and the bending of the floor slab 41 are satisfied so that the bending strength of the floor slab 41 satisfies the condition that the bending moment when the bearing bolt 36 contacts the inner surface of the through hole 25a. Resistance is set.
In other words, in the beam joint structure 2, the through hole is formed so that the magnitude of the bending moment acting on the floor slab 41 does not exceed the bending strength of the floor slab 41 until the bearing bolt 36 contacts the inner surface of the through hole 25 a. The inner diameter of 25a, the bending strength of the floor slab 41, and the like are set.

In the beam joining method of the present embodiment, the following steps are performed.
First, the worker places the small beam 31 so as to extend from the large beam 21 along the horizontal plane by joining the end of the small beam 31 to the large beam 21 (small beam arrangement step). At this time, the support beam 36 fixed to the small beam 31 is inserted into the through hole 25 a formed in the large beam 21 and joined together with the large beam 21 and the end of the small beam 31.
The floor slab 41 is joined (placed) above the small beam 31 (floor slab placing step). The bending strength of the floor slab 41 is equal to or greater than the bending moment when the bending moment acts on the floor slab 41 and the bolt shaft 36a of the bearing bolt 36 contacts the inner surface of the through hole 25a.
Beam joint structure 2 is manufactured by performing the above process.

As described above, according to the beam joining structure 2 and the beam joining method of the present embodiment, when the bearing bolt 36 contacts the inner surface of the through hole 25a, the bending moment acting on the beam 31 causes the bearing bolt 36 to The beam is transmitted between the end of the beam 31 and the beam 21 via the beam. The bending strength of the floor slab 41 is equal to or greater than the bending moment when the bearing bolt 36 contacts the inner surface of the through hole 25a due to the bending moment acting on the floor slab 41, thereby providing the inner surface of the through hole 25a. Even before the bearing bolt 36 contacts, even if a bending moment acts on the floor slab 41, damage to the floor slab 41 can be suppressed.
Furthermore, when the bearing bolt 36 contacts the inner surface of the through hole 25a, the bearing slab 36 uses the bearing bolt 36 for the resistance of the connection between the large beam 21 and the beam 31 by the bearing bolt 36 rather than the bending resistance of the floor slab 41 alone. The bending resistance of the floor slab 41 can exert higher rigidity and strength than the resistance of the joint between the large beam 21 and the small beam 31 alone, respectively.

Third Embodiment
Next, a third embodiment of the present invention will be described with reference to FIGS. 12 to 13B, and FIGS. 2A to 2B and FIGS. 11A to 11B described above. The reference numerals will be added and the description thereof will be omitted, and only different points will be described.
In the present embodiment, in the beam joint structure 2, the moving amount of the bearing bolt 36 when the bending moment acts on the floor slab 41 is quantitatively examined separately in each case.

[1. Method of calculating rotational rigidity and bending strength of floor slab 41]
_Assuming that the flexural rigidity of floor slab 41 is EI _slab (Nmm ² ) and the effective length of the joint between beam 31 and girder 21 is l _{j, slab} (mm), the rotational stiffness of floor slab 41 K _slab (Nmm / rad) is obtained by equation (A11).

[1.1. Calculation example of flexural rigidity EI _slab and flexural strength of floor slab 41]
The flexural rigidity EI _{slab of} the floor slab 41 and the flexural strength M _{slab, Rd} (N mm) of the floor slab 41 can be calculated, for example, in each case according to the following equation:

[1.1.1. When the floor slab 41 is a concrete slab]
When the floor slab 41 is a concrete slab having no reinforcing bars such as the first reinforcing bar 43 and the second reinforcing _bar , the bending rigidity EI _{slab of} the floor slab 41 and the bending strength M _{slab and Rd} of the floor slab 41 are It is calculated by the equations (A14) and (A15) using the equation (A13).
However, Young's modulus of concrete E _c (N / mm ² ), effective width of concrete slab b _eff (mm), effective thickness of concrete slab t _slab (mm), compressive strength of concrete f _c (N / Mm ² )

Although the method of determining the effective width b _eff of the concrete slab is not particularly limited, for example, as shown in FIG. 3, the pitch between the small beams 31 adjacent in the first direction X can be the effective width b _eff . Also, the effective width b _eff is, for example, British Standards "Eurocode 4: Design of composite steel and concrete structures-Part 1-1: General rules and rules for buildings", or "Various synthetic structural design guidelines and explanations", It can be decided based on the Architectural Institute of Japan, etc.
In determining the effective width b _eff of the concrete slab, the influence of the rigidity and the number of second reinforcing bars may be taken into consideration.

For example, as shown in FIG. 2A, the effective thickness t _slab of the concrete _slab is a value obtained by subtracting the height D _p of the convex portion of the deck plate 42 from the thickness D _s (mm) of the floor slab 41 (D _s −D _p ) can be. The recess formed in the concrete 44 by the deck plate 42 extends along the first direction X. In the concrete 44, even if a convex portion is formed between the concave portion and the concave portion, this convex portion is not effective for bending moment around an axis parallel to the first direction X. For this reason, in the concrete 44, some or all of the heights of the protrusions are not considered.
For example, when the recess formed in the concrete 44 extends along the second direction Y, the thickness t _slab of the floor slab 41 is more than the value of (D _s −D _p ). It may be a value close to D _s .

[1.1.2. In the case where floor slab 41 is a reinforced concrete slab (cracking of concrete is not acceptable)
In this case, the concrete maintains a tensile force. The flexural rigidity EI _slab of the floor slab 41 is calculated by equation (A18) using equations (A16) and (A17).
However, the Young's modulus of the reinforcing bar (steel) is E _S (N / mm ² ), the effective sectional area of the first reinforcing bar 43 is a _r (mm ² ), the upper surface 41 a of the floor slab 41 and the central axis of the first reinforcing bar 43 A distance of D _r (see FIG. 2A) (mm), a Young's modulus ratio which is a ratio of a Young's modulus E _S of a reinforcing bar to a Young's modulus E _c of concrete is n _E.
The effective sectional area a _r of the first reinforcing bar 43 is, for example, the sectional area of the plurality of first reinforcing bars 43 when the plurality of first reinforcing bars 43 are arranged within the effective width b _eff of the concrete slab. It will be the sum.

The bending strength _{Mslab, Rd} of the floor slab 41 is calculated by the equation (A20) using the equations (A12) and (A19).

[1.1.3. In the case where floor slab 41 is a reinforced concrete slab (cracks in concrete are acceptable)
In this case, the flexural rigidity EI _slab of the floor slab 41 is calculated by the equation (A24) using the equations (A21) to (A23).

The bending strength _{Mslab, Rd} of the floor slab 41 is calculated by the equation (A27) using the equations (A25) and (A26).
However, let f _sd (N / mm ² ) be the yield stress or tensile strength of the rebar. The function min (A, B) means the smaller value of A and B (however, the value of A when A and B are the same value).

[1.2. Calculation example of effective length l _{j, slab} of joint]
The effective length l _{j, slab} of the joint can be, for example, the distance from the center of the web 22 of the girder 21 to the center of the bolt row of the bearing bolt 36 in the second direction Y (see FIG. 2A).

[2. Derivation of a conditional expression in which the bearing bolt 36 contacts the inner surface of the through hole 25a]
[2.1. When the gap before the bending moment acts on the floor slab 41 is g _bb
A gap between the through hole 25a and the bolt shaft 36a of the bearing bolt 36 before the bending moment acts on the floor slab 41 is represented by _gbb (mm). When a bending moment acts on the floor slab 41, the floor slab 41 and the beam 31 bend. At this time, the bolt shaft 36 a of the bearing bolt 36 contacts the inner surface of the lower end through hole 25 aB. Further, depending on the conditions, the bolt shaft 36a of the bearing bolt 36 contacts the inner surface of the upper end through hole 25aA.
When a load such as a load is applied and the floor slab 41 is subjected to bending deformation, the rotation angle of the end portion of the beam 31 which bends and deforms with the floor slab 41 is set as θ _j (rad (radian)). The condition for the bolt shaft 36a of the bearing bolt 36 to contact the inner surface of the lower end through hole 25aB is the (A31) type. However, as shown in FIG. 2A, the distance between the central axis of the lower end through hole 25aB and the upper surface 41a of the floor slab 41 is x _b1 (mm), and the distance between the neutral axis C1 of the floor slab 41 and the upper surface 41a of the floor slab 41 And x _n (mm).

Assuming that the rotation angle when an equal sign is established in the equation (A31) is θ _{j, t} (rad), the rotation angle θ _{j, t} is calculated by the equation (A32).

On the other hand, the condition that the magnitude of the bending moment does not exceed the bending resistance M _{slab, Rd} of the floor slab 41 until the bolt shaft 36 a of the bearing bolt 36 contacts the inner surface of the lower end through hole 25 aB is equation (A33) is there. However, let the bending moment generated in the floor slab 41 when the rotation angle of the end of the beam 31 be θ _{j, t be} M _{slab, t} (N mm).

  Substituting the equation (A32) into the equation (A33) and rearranging, the equation (A34) is obtained.

[2.2. In the case of determining the gap g _{bb in} consideration of the rotation angle of the end of the beam 31 before the floor slab 41 is hardened]
The beam 31 and the floor slab 41 are constructed, for example, according to the following procedure.
(1) Temporarily fasten the end of the small beam 31 to the large beam 21 with a bearing bolt 36.
(2) Join the deck plate 42 above the beam 31.
(3) The first reinforcing bar 43 and the second reinforcing bar are arranged on the beam 31 via a spacer (not shown).
(4) The concrete before hardening is placed on the deck plate 42.
(5) The concrete is hardened to obtain hardened concrete 44. Thus, the floor slab 41 is formed on the beam 31.

In the steps (1) to (4), the gravity acting on the beam 31 is supported only by the beam 31. Then, only when the concrete is hardened by performing the step (5), it is integrated with the small beam 31 and the concrete 44 to become a synthetic beam. The beam 31 acting as a composite beam and the gravity acting on the floor slab 41 are supported by the beam 31 and the floor slab 41.
Therefore, before the beam 31 and the floor slab 41 become a composite beam, the gravity or the like acts on the beam 31 to rotate the end of the beam 31.

Here, it is assumed that the small beam 31 before becoming a composite beam is supported at both ends by pin joints (pin bearings). The mass (small weight) of the small beam 31 obtained by converting the length of the small beam 31 to l (mm), the load per unit length of the small beam 31 w (N / mm), the inner diameter of the through hole 25a is d ₀ ( mm), the outer diameter of the bolt shaft 36a of the bearing bolt 36 is d _b (mm), the distance between the central axis of the upper end through hole 25aA and the upper surface 41a of the floor slab 41 is x _b2 (mm) _{Let the} stiffness be EIS (Nmm ² ).
For example, when the mass of the small beam 31 is 0.02 (kg) per 1 (mm), the mass of the small beam 31 converted to the load per unit length of the small beam 31 is (0.02 It becomes 0.196 (N / mm) from the formula of 9.8 9.8).
In this way, it is assumed that an equally distributed load acts on the beam 31.

The gap g _bb (mm) between the through hole 25a and the bolt shaft 36a of the bearing bolt 36 is calculated by the equation (A35) (see FIG. 11A). When viewed in the first direction X, the through holes 25a and the bolt shafts 36a are circular. The gap g _bb (mm) is the maximum value of the gap between the through hole 25a and the bolt shaft 36a.

Before the bending moment acts on the floor slab 41, when the beam 31 is bent by the gravity acting on the floor slab 41, the end of the beam 31 is the rotation angle θ _j calculated from the equation (A36) _{. 0} (rad) rotate.
The distance between the bearing bolt 36 disposed at the lowermost position and the neutral axis C3 of the beam 31 is the value of the equation {(x _b1 −x _b2 ) / 2}. Therefore, the bearing bolt 36 disposed at the lowermost position moves by Δg (mm) obtained from the (A37) formula to the outside in the second direction Y with respect to the lower end through hole 25aB (see FIG. 12).

Although Δg is determined based on a value obtained by converting the mass of the small beam 31 into a load per unit length of the small beam 31, Δg is the mass of the small beam 31 and the floor slab 41 before the concrete is hardened. The weight of the small beam 31 may be determined based on a value converted to the load per unit length of the beam 31. In this case, Δg becomes large.
The bearing bolt 36 disposed at the uppermost position may move Δg (mm) inward in the second direction Y with respect to the upper end through hole 25aA.
Thereby, before the bending moment acts on the floor slab 41, when the beam 31 is bent by its own weight, a gap g _bb (mm,) between the lower end through hole 25aB and the bolt shaft 36a of the bearing bolt 36. 12) is calculated by equation (A38).

Furthermore, in the construction procedure of the above-mentioned beam 31 and floor slab 41, when the beam 31 is temporarily fixed by the bearing bolt 36, as shown in FIG. 13A to FIG. 13B, the penetration provided in the second shear plate 25. The through holes 32a (see also FIG. 3) provided in the holes 25a and the web 32 of the beam 31 are shifted by the value of the equation (d ₀ -d _b ) in the vertical direction by the weight of the beam 31. FIG. 13B also shows a partially enlarged cross-sectional view.
The gap g _bb ′ in the second direction Y at this time is smaller than the gap g _bb calculated by the equation (A38). Therefore, if the bending strength of the floor slab 41 is set so as to satisfy the equation (A34) using the gap g _bb calculated by the equation (A38), the design on the safety side is achieved.

When the plurality of through holes 25a (the bearing bolts 36) are provided at a constant pitch, the vertical pitch of the plurality of through holes 25a is p _v (mm), and the number of the plurality of through holes 25a (a plurality of support holes Assuming that the number of pressure bolts 36 is n, equation (A39) holds. Substituting the equation (A39) into the equation (A38) yields the equation (A40).

Hereinafter, the above embodiment will be described based on examples and comparative examples.
In all the following examples and comparative examples, dimensions, physical property values and the like are as follows.
Young's modulus of the reinforcing bars _{E S} is ^{205000 (N / mm 2),} ( see FIG. 2A) plate thickness t of the deck plate is 1.2 (mm), the Young's modulus of the concrete _{E c} is 14000 (N / ^mm 2), the floor Slab thickness D _s is 190 (mm), floor slab effective width b _eff is 2000 (mm), distance between first rebars (pitch) p _R is 100 (mm), upper surface of floor slab and first rebar The distance D _r to the central axis is 25 (mm).

Thereby, Young's modulus ratio n _E which is a ratio of Young's modulus E _S of reinforcing bars to Young's modulus E _c of concrete becomes 14.64. The number n _{R of} first rebars is 19 according to the equation (b _eff / p _R −1).

[1. When the floor slab is a concrete slab (without rebar)
The dimensions and physical property values and the like of Comparative Example A and Examples A1 to A3 are shown in Table 4. In this case, even if a bending moment acts on the concrete slab, the floor slab is designed such that the bending moment does not break the concrete slab. Therefore, the tensile strength of the concrete determines whether the concrete slab is damaged or not.

In Comparative Example A, the compressive strength f _{c of the} concrete is 40 (N / mm ² ). Using the compressive strength f _{c of} concrete, the value of the tensile strength f _{c, t} (N / mm ² ) can be obtained from the formula (A12). The height D _p of the convex portion of the deck plate is 50 (mm). For the first rebar, the yield stress or tensile strength f _sd is 400 (N / mm ² ), and the outer diameter D _R (mm) is 10 (mm). In this case, the effective cross-sectional area _a r a first reinforcing bar (mm ²⁾ is calculated to be ^{_{(πn R D R 2/4}} ) 1492 from the formula of (mm ^2). Here, π is the circle ratio.
The rebar ratio will be described later.
When the floor slab is a concrete slab, the floor slab does not have the first rebar. However, the values for the first reinforcing bar were determined for the other cases described later.

The distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 590 (mm), and the gap g _bb between the through hole and the bolt axis of the support bolt is 0.5 ( mm).

The effective thickness t _slab of the concrete _slab is calculated to be 141.2 (mm) from the equation (D _s −D _p + t). As described above, the effective thickness t _slab may be calculated from the equation (D _s −D _p ).
Reinforcement ratio described _above, the equation of _{{a r / (b eff ·} (t slab -D r))}, is calculated to be 0.64 (%). The distance x _n between the neutral axis of the floor slab and the top surface of the floor slab is calculated to be 70.6 (mm) according to the equation (t _slab / 2).

Flexural rigidity _{EI slab} of the floor slabs _is calculated as ^{_{{(b eff t slab 3/}} 12) · E c / 10 9} 6569 the equation of (kNm ^2). Using the effective width b _eff of the floor slab and the effective thickness t _slab of the concrete slab, the value of the cross section coefficient Z _c of the floor slab can be obtained as 6645813 (mm ³ ) from the equation (A13).
The flexural strength M _{slab, Rd} of the floor slab can be calculated as 23.5 (kNm) from the formula (A15).
Although not shown in Table 4, the variable φ ₁ is calculated to be 3.58 × 10 ⁻⁶ (m ⁻¹ ) according to the formula of (M _{slab, Rd} / EI _slab / 10 ³ ).
The effective length l _{j, slab} of the joint is 200 (mm).
Although not shown in Table 4, the rotation angle φ ₂ is calculated to be 0.0007 (rad) from the equation (φ ₁ · l _{j, slab} ).

The rotational stiffness K _slab of the floor _slab is calculated as 32844 (kNm / rad) according to the formula {EI _slab / (l _{j, slab} / 10 ³ )}.
The ratio of flexural strength _{Mslab, Rd} to rotational stiffness _Kslab in the floor slab (hereinafter referred to as the flexural strength ratio) is calculated to be 0.0007 from the equation ( _{Mslab, Rd} / _Kslab ).
The ratio of the gap g _bb to the difference between the distance x _b1 and the distance x _n (hereinafter referred to as the gap ratio) is calculated as 0.0010 from the equation {g _bb / (x _b1 −x _n )}.

The aforementioned equation (A34) can be rephrased as a condition in which the bending resistance ratio is equal to or greater than the gap ratio. That is, the embodiment becomes an example when the bending resistance ratio is equal to or more than the gap ratio, and the comparison example becomes when the bending resistance ratio is smaller than the gap ratio.
In Comparative Example A in Table 4, the bending strength ratio is smaller than the gap ratio, and the bending strength of the floor slab is bending when a bending moment acts on the floor slab and the bolt axis of the bearing bolt contacts the inner surface of the through hole. It was found to be less than the magnitude of the moment.

In the beam joint structure of Example A1, in the beam joint structure of Comparative Example A, the compressive strength f _{c of} concrete is 60 (N / mm ² ), and the effective length l _j of the joint is 250 (mm). . By changing the compressive strength f _c and the effective length l _{j, slab} , values from the value of the tensile strength f _{c, t} to the bending resistance ratio and the gap ratio are calculated in the same manner as described above.
In the beam joint structure of Example A1, the bending strength ratio is equal to or higher than the gap ratio, and the bending strength of the floor slab is determined by the bending moment acting on the floor slab and the bolt shaft of the bearing bolt contacting the inner surface of the through hole. It turned out that it is more than the size of bending moment.

In the beam joint structure of Example A2, in the beam joint structure of Comparative Example A, the height D _p of the convex portion of the deck plate was 90 (mm). In the beam bonded structure of Example A3, in the beam bonded structure of Comparative Example A, the compressive strength f _{c of} concrete is 100 (N / mm ² ), and the distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 690 (mm), the gap g _bb between the through hole and the bolt shaft of the bearing bolt was 1.0 (mm), and the effective length l _{j, slab} of the joint was 300 (mm).

  Also in the beam joint structure of Example A2 and Example A3, the bending strength ratio is equal to or more than the gap ratio, and the bending strength of the floor slab is determined by the bending moment acting on the floor slab and the bolt of the bearing bolt on the inner surface of the through hole. It turned out that it is more than the magnitude | size of a bending moment when an axis | shaft contacts.

[2. When the floor slab is a reinforced concrete slab (concrete cracking is not acceptable)
The dimensions and physical property values and the like of Comparative Example A and Examples A1 to A3 are shown in Table 5. In this case, as in the case where the floor slab is a concrete slab, the floor slab is designed such that even if a bending moment acts on the floor slab, the bending moment does not break the concrete of the floor slab.

In Comparative Example A, the compressive strength f _{c of the} concrete is 40 (N / mm ² ), and the height D _p of the convex portion of the deck plate is 50 (mm). For the first rebar, the yield stress or tensile strength f _sd is 400 (N / mm ² ), and the outer diameter D _R is 10 (mm). The distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 580 (mm), and the gap g _bb between the through hole and the bolt axis of the support bolt is 0.5 ( mm). The effective length l _{j, slab} of the joint is 200 (mm).
By changing the compressive strength f _c , the height D _p of the convex portion, and the like, values from the value of the tensile strength f _{c, t} to the bending resistance ratio and the gap ratio are calculated in the same manner as described above.

However, in this case, the distance x _n between the neutral axis of the floor slab and the upper surface of the floor slab is calculated to be 67.3 (mm) from the formula (A16). Second moment _{I Uncracked} is calculated as (A17) from equation 34922635 (mm ^4). The flexural rigidity EI _slab of the floor _slab is calculated as 7159 (kNm ² ) according to equation (A18).
From the equation (A19) _, the value of the cross section coefficient Zc _{, r} of the floor slab can be obtained as 7595494 (mm ³ ) using the moment of inertia of area I _uncracked , Young's modulus ratio n _E and distance x _n . The flexural strength _{Mslab, Rd} of the floor slab is calculated to be 26.90 (kNm) from the equation (A20).

  In the beam joint structure of Comparative Example A, the bending strength ratio (0.0008) is smaller than the clearance ratio (0.0010), and the bending strength of the floor slab is such that a bending moment acts on the floor slab and the inner surface of the through hole It turned out that it is less than the magnitude | size of a bending moment when the bolt shaft of a bearing bolt contacts.

In the beam joint structure of Example A1, in the beam joint structure of Comparative Example A, the height D _p of the convex portion of the deck plate was 100 (mm), and the outer diameter D _R of the first reinforcing bar was 19 (mm). In the beam bonded structure of Example A2, in the beam bonded structure of Comparative Example A, the compressive strength f _c of the concrete was 80 (N / mm ² ). In the beam joint structure of Example A3, in the beam joint structure of Comparative Example A, the effective length l _{j, slab} of the joint was 300 (mm).
In the beam connection structure of Example A1 to Example A3, the bending strength ratio is equal to or more than the gap ratio, and the bending strength of the floor slab is determined by the bending moment acting on the floor slab and the bolt shaft of the bearing bolt on the inner surface of the through hole. Was found to be greater than or equal to the magnitude of the bending moment at the time of contact.

[3. When the floor slab is a reinforced concrete slab (cracks in concrete are acceptable)
The dimensions and physical property values and the like of Comparative Example A and Examples A1 to A3 are shown in Table 6. In this case, it is also assumed that when the bending moment acts on the floor slab, the concrete of the floor slab breaks due to the bending moment.

In Comparative Example A, the compressive strength f _{c of the} concrete is 40 (N / mm ² ), and the height D _p of the convex portion of the deck plate is 50 (mm). For the first rebar, the yield stress or tensile strength f _sd is 400 (N / mm ² ), and the outer diameter D _R is 10 (mm).
The distance x _b1 between the central axis of the lower end through hole and the upper surface of the floor slab is 350 (mm), and the gap g _bb between the through hole and the bolt axis of the support bolt is 1.5 ( mm). The effective length l _{j, slab} of the joint is 200 (mm).
By changing the compressive strength f _c , the height D _p of the convex portion, and the like, values from the value of the tensile strength f _{c, t} to the bending resistance ratio and the gap ratio are calculated in the same manner as described above.

However, in this case, using the effective cross-sectional area a _r of the first rebar, the effective width b _eff of the floor slab, the Young's modulus ratio n _E , and the effective thickness t _slab of the concrete slab, the equivalent rebar is obtained according to equation (A21) The value of the ratio p _s is determined to be 0.077. The distance x _n between the neutral axis of the floor slab and the top surface of the floor slab is calculated to be 100.6 (mm) according to equation (A22). The cross-sectional second moment I _cracked is calculated as 11575694 (mm ⁴ ) from the formula (A23). The flexural rigidity EI _slab of the floor slab 41 is calculated as 2373 (kNm ² ) from the equation (A24).
Distance x _n , distance D _r between top surface 41a of floor slab 41 and central axis of first reinforcing bar 43, effective thickness of concrete slab t _slab , effective width of concrete slab b _eff , concrete compressive strength f _c , rebar Using the yield stress or tensile strength f _sd and the effective cross-sectional area a _r of the first rebar _, the value of the flexural strength M _c, R _{d of the} floor slab determined by concrete according to the equation (A 25) is 166.9 (kNm) From the equation (A26) _, the value of the flexural strength M _{r, R d of the} floor slab determined by the reinforcing bar is determined to be 61.3 (kNm).
The flexural strength M _{slab, Rd} of the floor slab is calculated to be 61.3 (kNm) from the equation (A27).

  In the beam joint structure of Comparative Example A, the bending strength ratio (0.0052) is smaller than the clearance ratio (0.0060), and the bending strength of the floor slab is such that a bending moment acts on the floor slab and the inner surface of the through hole is formed. It turned out that it is less than the magnitude | size of a bending moment when the bolt shaft of a bearing bolt contacts.

In the beam joint structure of Example A1, in the beam joint structure of Comparative Example A, the outer diameter D _R of the first reinforcing bar was 16 (mm). In the beam bonded structure of Example A2, the yield stress or tensile strength f _sd of the first reinforcing bar in the beam bonded structure of Comparative Example A was 500 (N / mm ² ). In the beam joint structure of Example A3, in the beam joint structure of Comparative Example A, the height D _p of the convex portion of the deck plate was 70 (mm).
In the beam connection structure of Example A1 to Example A3, the bending strength ratio is equal to or more than the gap ratio, and the bending strength of the floor slab is determined by the bending moment acting on the floor slab and the bolt shaft of the bearing bolt on the inner surface of the through hole. Was found to be greater than or equal to the magnitude of the bending moment at the time of contact.

As described above, according to the beam joint structure 2 and the beam joint method of the present embodiment, the bending strength M _{slab, Rd of} the floor slab 41, the rotational rigidity K _slab of the floor slab 41, the through hole 25a and the bearing bolt 36 gap _{g bb,} distance _{x n} and the upper surface 41a of the neutral axis C1 and the floor slab 41 of the distance x _b1, and floor slabs 41 between the central axis and the upper surface 41a of the floor slab 41 of the lower through-holes 25aB and the bolt shaft 36a Satisfies the equation (A34). As a result, the state where the bending moment is transmitted between the end of the beam 31 and the large beam 21 via the bearing bolt 36 is quantitatively evaluated, and damage to the floor slab 41 is effectively suppressed. be able to.
Also, using the equation (A38) for the value of the gap g _bb , consider the state in which the beam 31 is bent by the gravity acting on the beam 31 before the floor slab 41 on the beam 31 is cured. Thus, the gap g _bb between the through hole 25 a and the bolt shaft 36 a of the bearing bolt 36 can be quantitatively evaluated, and damage to the floor slab 41 can be more effectively suppressed.

  According to the present invention, when the support member and the beam are bearing-bonded using bolts, damage to the floor slab can be suppressed even if a bending moment acts on the floor slab, and before the floor slab is damaged. By contacting the bolt, it is possible to exert higher rigidity and load resistance than the floor slab alone or the bolted joint alone.

2 Beam connection structure 21 Large beam (supporting member)
25a through hole 31 beam (beam)
36 bolt 41 floor slab 41a upper surface 50 synthetic through hole C1 neutral axis M _slab, bending strength of _Rd floor slab

Claims (11)

A support member,
A beam whose end is joined to the support member;
A floor slab joined above the beams;
A bolt for joining the end portion and the support member in a state in which the first through hole at the end portion and the second through hole of the support member are inserted into a composite through hole formed by overlapping each other;
Equipped with
A design method of a beam joint structure in which gaps exist between the first through hole and the bolt and between the second through hole and the bolt in the longitudinal direction of the beam,
By giving bending deformation to the floor slab, the bolt moves relative to the first through hole and the second through hole in the longitudinal direction of the beam, and the inner surface of the first through hole and Bending of the floor slab so that the bending moment acting on the floor slab becomes smaller than the bending strength of the floor slab until the bearing jointing state is reached in which the bolt contacts the inner surface of the second through hole A method of designing a beam joint structure, comprising the step of setting a proof stress. The floor slab is a concrete slab provided on the support member,
The method for designing a beam joint structure according to claim 1, wherein the bending strength of the floor slab is calculated based on the compressive strength of concrete used for the floor slab. The floor slab is a reinforced concrete slab provided on the support member, and reinforcing bars in the floor slab are extended in the longitudinal direction of the beam so as to straddle the support member,
The beam joint according to claim 1 or 2, wherein the bending strength of the floor slab is calculated based on Young's modulus and strength of concrete used for the floor slab and Young's modulus and strength of the reinforcing bar. How to design the structure.   The floor slab has a structure in which concrete is cast on a deck plate having a plurality of grooves extending in one direction in the longitudinal direction of the beam, and the grooves are arranged to extend along a direction intersecting the longitudinal direction of the beam The method for designing a beam joint structure according to any one of claims 1 to 3, wherein: A plurality of the synthetic through holes are provided in the end portion and the support member, and among the plurality of synthetic through holes, the synthetic through holes are arranged farthest from the floor slab in the vertical direction so as to satisfy the equation (1). A clearance between the inner surface of the second through hole in the longitudinal direction of the beam and a distance between the bolt and the inner surface of the first through hole in the longitudinal direction of the beam; Total value of clearances g _b (mm), rotational rigidity of the floor slab K _slab (N mm / rad), bending resistance of the floor slab M _{slab, Rd} (N mm), neutral axis of the floor slab subjected to bending deformation And a distance between the top surface of the floor slab x _n (mm) and a central axis of the composite penetration hole farthest from the floor slab in the vertical direction among the plurality of composite through holes and the top surface of the floor slab When Distance x _{b1 (mm)} design method for beam joining structure according to claim 1, characterized in that to determine.

The distance between the inner surfaces of the first through holes in the longitudinal direction of the beam is d ₀₁ (mm), the distance between the inner surfaces of the second through holes in the longitudinal direction of the beam is d ₀₂ (mm), the outside of the bolts A diameter d _b (mm), a distance between a central axis of the synthetic through hole closest to the floor slab among the plurality of synthetic through holes and an upper surface of the floor slab x _{b 2} (mm), a length of the beam l (mm) a is the flexural rigidity EI S of the beam _(Nmm ^2), calculates the sum of the mass of the floor slab mass and the beam of the beam to support, the product of the sum and the gravitational acceleration of the mass When the weight w (N / mm) per unit length of the beam is divided by the length of the beam, the gap g _b is determined so as to satisfy the equation (2). The design method of the beam joint structure of claim 5.

  The beam joint structure designed by the design method according to any one of claims 1 to 6, further comprising a step of joining the support member and the beam. A support member;
A beam whose end is joined to said support member;
A floor slab joined above the beams;
A bolt for joining the end portion and the support member in a state in which the first through hole at the end portion and the second through hole of the support member are inserted into a composite through hole formed by overlapping each other;
Equipped with
A beam joint structure in which gaps exist between the first through hole and the bolt and between the second through hole and the bolt in the longitudinal direction of the beam,
A plurality of the synthetic through holes are provided in the end portion and the support member;
A clearance between the inner surface of the second through hole farthest from the beam in the longitudinal direction of the beam and the bolt and the first through hole of the combined through hole arranged farthest from the floor slab in the vertical direction The total value g _b (mm) of the gap between the inner surface of the hole remote from the support member and the bolt, the rotational stiffness K _slab (N mm / rad) of the floor slab, and the bending resistance M _{slab, Rd of the} floor slab (N mm), the distance x _n (mm) between the neutral axis of the floor slab subjected to bending deformation and the upper surface of the floor slab , and, from among the plurality of synthetic through holes, the floor slab most in the vertical direction The distance x _b1 (mm) between the central axis of the farthest synthetic through hole and the upper surface of the floor slab satisfies the formula (3);
Beam joint structure characterized by

The floor slab comprises a deck plate having a plurality of grooves extending in one direction,
The beam joint structure according to claim 8, wherein the groove extends along a direction intersecting a longitudinal direction of the beam. The distance between the inner surfaces of the first through holes in the longitudinal direction of the beam is d ₀₁ (mm), the distance between the inner surfaces of the second through holes in the longitudinal direction of the beam is d ₀₂ (mm), the outside of the bolts A diameter d _b (mm), a distance between a central axis of the synthetic through hole closest to the floor slab among the plurality of synthetic through holes and an upper surface of the floor slab x _{b 2} (mm), a length of the beam l (mm) a is the flexural rigidity EI S of the beam _(Nmm ^2), calculates the sum of the mass of the floor slab mass and the beam of the beam to support, the product of the sum and the gravitational acceleration of the mass When the weight per unit length w (N / mm) of the beam is divided by the length of the beam, the gap g _b satisfies the equation (4)
Beam structure according to claim 9, characterized in that.

The beam joint structure according to any one of claims 8 to 10 , wherein a lower flange of the beam extending in a longitudinal direction of the beam and the support member are not joined to each other.

Images