JP6182387B2 - Building structure with frame consisting of small RC pillars - Google Patents

Description

  The present invention relates to a building structure having a frame made of a small-diameter RC column.

In general, if a small RC column has a structure in which end portions are rigidly joined so as to resist horizontal force, the horizontal proof strength is small, so that there is a problem that the small RC column is greatly damaged. It was.
Therefore, a separate horizontal resistance member such as a wall is provided on the same plane, and the small-diameter RC column 2 'is expected to follow only the horizontal displacement during an earthquake, so that the column head and the column base are made semi-rigid joint 4'. It is generally done. By adopting a semi-rigid joint or pin joint 4 ′, the stress acting on the small-diameter RC column 2 ′ is reduced as much as possible to improve the horizontal displacement followability (see FIG. 7).

  However, in this conventional method, it is necessary to provide a separate horizontal resistance member on the same plane so that the horizontal force can be appropriately transmitted by a rigid slab, and this is subject to great restrictions on the plan of the building. Become.

Kazumasa Imai, Junji Muramatsu, Naoko Okada, Tomohiro Terashima, Satoshi Hattori, Tsutomu Komuro: Structural performance of RC long columns using ultra-high-strength concrete (Part 1 to Part 3), Abstracts of Annual Conference of Architectural Institute of Japan, pp. 319 – 324, 2010.9

  The present invention was created to solve the various problems described above, and is an architectural structure having a frame made of a small-diameter RC column and capable of resisting horizontal force without impairing the degree of freedom in plan planning. The object is to provide an object with a simple configuration.

  Another object of the present invention is to make it difficult to damage the small-diameter RC column by adjusting the degree of pressure bonding of the beam or the foundation beam so that the beam or the foundation beam is separated before the column is damaged. To do.

The invention according to claim 1, diameter RC column is precast prestressed preparative concrete member, the bonding member such as a column base and the beam of the small diameter RC column is semirigid junction or pin junction,
Crimping Column Joints of stigma side and precast prestressed beams of said small-diameter RC column is formed so that the posts through, and installed in parallel with the substantially central height position of the beam-column joints Gahari Seiko It was set as the building structure which has the frame crimped | bonded by the PC steel wire .
Here, the joining member such as the beam to be semi-rigidly or pin-joined includes a foundation beam, a floor slab, a column and the like in addition to the beam. Further, the crimping joining member such as a beam to be crimped so as to pass through a column includes a foundation beam, a floor slab, and the like in addition to the beam.
Therefore, the beam to be joined on the lower side of the small-diameter RC column and the beam to be joined on the upper side are joined as a joining member in the case of semi-rigid joining or pin joining, and crimp-bonded by the joining method with the small-diameter RC column. In this case, a small-diameter RC column and a frame are formed as a pressure bonding member.
In addition, in this specification, the small-diameter RC column means that the value obtained by dividing the column member length by the smallest column width is an RC column of 5 or more.

In the invention according to claim 2, the small-diameter RC column is a precast prestressed concrete member, and the column base of the small-diameter RC column and a column beam joint such as a precast prestressed beam are formed through the column, and The column beam joint is crimped by a crimping PC steel wire installed in parallel at the approximate center height of the beam, and the column head side of the small RC column and the precast prestressed beam are semi-rigidly joined or pin joined. The building structure has a frame .

In the invention according to claim 3, in the small-diameter RC column, all main bars of the column are made of tension material, and a pressure-bonding member such as a beam on the other end side is made of precast concrete. By crimping with the RC pillar, it is a frame that resists horizontal force. By changing the degree of crimping, the separation moment and post-separation rigidity of the crimping part are adjusted, and the small-diameter RC pillar is damaged. It is characterized in that the stress generated at one end of the small-diameter RC column is controlled so as not to occur.
In this specification, the PC steel material includes a PC steel wire, a PC steel strand, a PC steel bar, or a deformed reinforcing bar.

  The invention according to claim 4 is characterized in that the semi-rigid joint is configured such that a joining bar is embedded substantially at the center of a cross section of the thin RC column, and bending moment stress generated in the thin RC column is reduced. Yes.

According to the first aspect of the present invention, prestress is introduced into the small-diameter RC column, and one end of the small-diameter RC column and a joining member such as a beam are semi-rigidly joined or pin-joined. By constructing the frame bonded with the pressure bonding member so that the other end and the column beam bonding portion of the pressure bonding member such as a beam are passed through the column, the frame of the building structure resists horizontal force. be able to.
In addition, since one end of the small-diameter RC column and a joining member such as a beam are semi-rigidly or pin-joined, a bending moment generated in the small-diameter RC column is reduced, and damage to the small-diameter RC column is suppressed. On the other hand, since the other end of the small-diameter RC column and the beam are pressure-bonded, they can resist horizontal force. A bending moment is generated in the small-diameter RC column depending on the degree of pressure bonding. However, since prestress is introduced into the small-diameter RC column, crack strength and bending strength are improved, and the column is not easily damaged. With this frame, there is no need to provide a separate horizontal resistance member as in the prior art, so the degree of freedom in building plan planning increases.

According to the invention according to claim 2, in the thin RC column, all or some of the main bars of the column are tension materials, and due to the adhesion between the main bars, the grout mortar in the sheath tube, the sheath tube and the concrete, Prestress is introduced into concrete. By using the main bar as the tension member, it is not necessary to separately arrange the tension member, so even when the cross section is small like a small-diameter RC column, the bar arrangement is simplified and not complicated. In particular, when using high-strength concrete, this method is extremely effective because the column cross section tends to be small.
In addition, when prestress is introduced by post-tension method using high-strength concrete, only the sheath tube having a small restraining force against the contraction of the concrete at the time of placing is disposed, and the main reinforcement having a large restraining force is provided. Since no is provided, it is possible to achieve an effect of reducing cracks and initial stress due to shrinkage of concrete.

  According to the invention of claim 3, the degree of pressure-bonding with the beam is adjusted by changing the tension force, the tension position of the PC steel material for pressure-bonding passing in the axial direction of the beam, and the beam length of the pressure-bonding portion. Since the stress generated in the small-diameter RC column can be controlled by the adjustment, the small-diameter RC column can be prevented from being damaged. In addition, since the pressure bonding member such as a beam is pressure-bonded to the small-diameter RC column, even if a gap is generated by separating the small-diameter RC column and the pressure bonding member such as the beam, the gap is closed again and separated. Will not continue.

According to the fourth aspect of the present invention, the semi-rigid joint for reducing the bending moment generated at the column end portion is to insert the joining bar into the joining bar sheath tube embedded in the approximate center of the small-diameter RC column section. Since the connecting bar is only arranged at the center of the cross section of the column, the cross section is small as in the case of the small-diameter RC column of the present invention, and it is easy even when the column main bar or tension bar is complicated. Can be arranged. In particular, when high-strength concrete of about 150 to 300 N / mm ² is used, the column cross-section becomes small. Therefore, a semi-rigid joint structure in which a joint bar is arranged at the approximate center of the cross-section of a small-diameter RC column is extremely effective. is there.

It is a frame conceptual diagram of the building structure of the present invention. It is the elements on larger scale of the frame of the Example of this invention. It is the elements on larger scale of the frame of the other Example of this invention. It is an AA arrow directional view of the small diameter RC pillar of FIG. It is a BB line arrow directional view of the small diameter RC pillar of FIG. It is CC arrow directional view of the small diameter RC pillar of FIG. It is a frame conceptual diagram of the building structure of a prior art.

The outline of the present embodiment will be described with reference to FIG. 1 conceptually illustrating the frame 1 of the building structure of the present embodiment.
Prestress is introduced into the small-diameter RC column 2, and the end surface of one end of the small-diameter RC column 2 is semi-rigidly bonded 4 or pin-bonded 4.
The other end portion is pressure-bonded to the beam, and a compression structure of the small-diameter RC column 2 and the beam 3 in which the beam-column joint portion 5 is formed as a column is formed (a compression structure 50 is shown in FIG. 2 to be described later). ).

By adopting a configuration in which the other end of the small-diameter RC column 2 is pressure-bonded to the beam 3 through the column, the frame 1 of the building structure that resists horizontal force can be obtained.
A bending moment is generated at the other end of the small-diameter RC column 2 according to the degree of pressure bonding of the beam 3. In response to this, by introducing prestress to the small-diameter RC column 2, it is possible to improve the cracking strength and bending strength and to construct the frame 1 in which the column is not easily damaged.
In FIG. 1, the entire building is constructed with the frame 1 of the present invention. However, a part of the building is constructed with the frame 1 of the present invention, and the other part of the building is constructed with another frame. You can also.

  In the frame 1 of the present invention, even if a bending moment acts on the small-diameter RC column 2 and a crack is generated once, the crack is closed by the prestress introduced into the small-diameter RC column 2 and the crack is repaired. .

  Further, the separation moment of the beam 3 and the rigidity after separation are adjusted by changing the tension force, the tension position of the wire 32, the beam seizure of the crimping portion, etc. from the PC steel for crimping passing in the axial direction of the beam 3 described later. be able to. By adjusting the separation moment of the beam and the rigidity after separation, the stress generated in the small-diameter RC column 2 can be controlled, so that the small-diameter RC column 2 is not easily damaged. Further, since the beam 3 is pressure-bonded to the small-diameter RC column 2, even if the small-diameter RC column 2 and the beam 3 are separated and a gap is generated, the gap is closed again and the separated state does not continue. .

  On the other hand, the end surface of one end of the small-diameter RC column 2 is a semi-rigid joint 4, and the stress generated in the column 2 is reduced. With this frame 1, it is not necessary to provide a separate horizontal resistance member as in the prior art, so that the degree of freedom in building plan planning increases.

  A concrete building structure 1 is partially enlarged and shown in FIG. The column base of the small-diameter RC column 2 is semi-rigidly bonded 4, the column head side is crimped to the beam 3, the column-beam connecting portion 5 is through the column, and prestress is introduced into the small-diameter RC column 2. In this embodiment, the small-diameter RC column 2 is a precast prestressed concrete member, and the beam 3 is a precast member. In this embodiment, high-strength concrete is used for the small-diameter RC column 2.

The column base is connected to a joining member 43 such as a beam, a foundation beam, a floor slab, or a column by a joining bar 41 disposed in a joining bar sheath tube 42 embedded in a substantially central section of the thin RC column 2. It is rigidly joined.
Therefore, the bending moment generated in the column base is reduced, and damage to the small-diameter RC column 2 is suppressed. Since the joining bar 41 is only disposed at the substantially center of the cross section of the column 2, it is easily arranged even when the cross section is small and the bar main bar or the tension member 21 is complicated as in the small-diameter RC column 2 of the present invention. Can be streaked.
In particular, when a high-strength concrete of about 150 to 300 N / mm ² is used as in this embodiment, the column cross section becomes small. For this reason, the semi-rigid joint structure in which the joint bar 41 is disposed at the approximate center of the cross section of the small-diameter RC column 2 is extremely effective.

Since the small-diameter RC column 2 is composed of a precast member, a sheath tube 42 for insertion of the joining bar 41 is embedded in the stigma and pedestal, so that the column head and pedestal beam, foundation beam, floor slab, column, etc. The joint 6 with the joining member 43 and the inside of the sheath tube 42 are integrally filled with grout mortar.
The joining bars 41 are integrated with the column bases of the upper floor small diameter RC columns 2 and protrude below the columns 2 at the factory manufacturing stage of the small diameter RC columns 2. It is possible to adopt a form that is integrated with and protrudes above the pillar 2 or a form of another member that is not integrated with the small-diameter RC pillar 2.
Further, the semi-rigid joint structure of the small-diameter RC column 2 is not limited to the above example.
Further, a pin joint structure can be used instead of the semi-rigid joint.

  Prestress of the small-diameter RC column 2 uses all the main bars 21 of the column 2 as tension materials, and prestress is introduced into the concrete by the adhesion between the main bar 21, the grout mortar in the sheath tube 22, the sheath tube 22 and the concrete. Has been.

Examples of the procedure for introducing prestress into the small-diameter RC column 2 include the following method.
a. Concrete is placed in a state in which the hollow sheath tube 22 is disposed at the position of all the main bars 21.
b. After the concrete is hardened, the main bar 21 is inserted into the column main bar sheath tube 22.
c. The main muscle 21 is tensioned and its end is assumed to be worn with a nut or the like.
d. Fill the sheath tube 22 with grout mortar.
e. After the grout mortar has hardened, the assumed attachment of the nut or the like is released, and prestress is introduced into the concrete of the small-diameter RC column 2 by the adhesion between the main reinforcement 21, the grout mortar, the sheath tube 22 and the concrete. The main reinforcement 21 protruding from the end of the small-diameter RC column 2 is cut.

  According to the method in which the prestress is introduced into the small-diameter RC column 2 using all the main bars 21 of the column 2 as the tension material, there is no need to separately arrange the tension material, so that the cross section is small like the small-diameter RC column 2. Even in this case, the reinforcement is not complicated. In particular, when using high-strength concrete, this method is extremely effective because the column cross section tends to be small.

  In addition, when using the above high-strength concrete, only the sheath tube 22 having a small restraint against the contraction of the concrete at the time of placing is disposed, and the main bar 21 having a large restraining force is not disposed. The effect which the crack and the initial stress by shrinkage | contraction of concrete are relieved can be show | played.

In this embodiment, all the main muscles are used as tendons, but some main bars may be used as tendons.
Moreover, the prestress introduction | transduction procedure of the small diameter RC pillar 2 is not limited to said example.
Furthermore, the tension material for introducing the prestress into the small-diameter RC column is not limited to the main reinforcement shown in the present embodiment, and although not shown, a PC steel wire, a PC steel strand, a PC steel rod, etc. Good.

The column beam joint 5 is crimped to the beam 3 by a wire 33 from a crimping PC steel. By setting it as this structure, it becomes the frame 1 of the building structure which resists horizontal forces, such as an earthquake.
Thereby, since it is not necessary to provide a horizontal resistance member separately, the freedom degree of the plan of a building increases.

The precast beam 3 and the column beam joint 5 are individually provided with a sheath tube 34 of a crimped PC steel strand 33, and the crimped PC steel strand 33 is inserted, tensioned and fixed in the sheath tube 34, and the sheath tube 34 and the joint 6 between the beam 3 and the small-diameter RC column 2 are filled with grout mortar.
In addition, the grout mortar is also filled in the joint 6 between the small-diameter RC column 2 and the small-diameter RC column 2 (in the lowermost column base, between the joint members).

In the present embodiment, the degree of pressure bonding is appropriately determined, and the separation moment and post-separation rigidity of the pressure bonding portion are adjusted.
Thereby, the stress generated at the head of the thin RC column 2 is controlled so that the thin RC column 2 is not damaged.

The degree of pressure bonding is determined according to the relationship between the resisting horizontal force and the column strength.
When resisting a large horizontal force, it is necessary to increase the separation moment of the crimping portion. However, the separation moment and the rigidity after separation are required to be as small as possible so that the stress acting on the column does not exceed the proof stress of the column.
The separation moment and the post-separation rigidity can be adjusted by the crimping force, the crimping position, the beam of the crimping portion, and the like.

Since the beam 3 is crimped to the beam-to-column joint 5, even if the beam-to-column joint 5 and the beam 3 are separated and a gap is formed between them, the gap is closed by the tension of the wire 33 from the crimping PC steel. .
Note that the PC steel material for crimping the small-diameter RC column 2 and the beam 3 is not limited to the PC steel wire as in the above example, but may be a PC steel bar or a deformed reinforcing bar, although not shown.

Other examples

In the above-described embodiment, the columnar base of the small-diameter RC column 2 is semi-rigidly bonded and the column head is bonded to the beam 3, but the other embodiment is partially enlarged in FIG. As shown in the figure, the side of the stigma is a semi-rigid joint 4 and the column base is crimped to the beam, contrary to the embodiment.
That is, the column head of the small-diameter RC column 2 is semi-rigidly joined 4, the column base is crimped to the beam 3 or the foundation beam 7, the column-beam joint 5 is through the column, and the small-diameter RC column 2 is prestressed. Has been introduced.
Also in the present embodiment, the thin RC column 2 is a precast prestressed concrete member, the beam 3 and the foundation beam 7 are precast members, and the thin RC column 2 is made of high-strength concrete. This is the same as the embodiment described above.

  According to this, since the column base of the small-diameter RC column is pressure-bonded to the foundation beam through the column as in the embodiment, it can be a frame of a building structure that resists horizontal force. A bending moment is generated in the column base of the small-diameter RC column 2 according to the degree of pressure bonding of the beam 3 or the foundation beam 7. By introducing prestress to the small-diameter RC column 2, the crack strength and the bending strength are improved. Thus, it is possible to construct a frame in which the pillar is not easily damaged.

  Even if a bending moment acts on the small-diameter RC column 2 and a crack is generated once, the crack is closed by the prestress introduced into the small-diameter RC column 2 and the crack is repaired.

  Furthermore, the degree of pressure bonding with the beam can be adjusted by changing the tension of the wire from the PC steel for pressure bonding passing in the axial direction of the beam 3 or the foundation beam 7. Since the stress generated in the small-diameter RC column 2 can be controlled by adjusting the degree of pressure bonding, the small-diameter RC column 2 is hardly damaged. Furthermore, since the beam 3 or the foundation beam 7 is pressure-bonded to the small-diameter RC column 2, even if the small-diameter RC column 2 and the beam 3 or the foundation beam 7 are separated to form a gap, the gap is closed again and separated. This condition will not continue.

On the other hand, the end face of the head of the small-diameter RC column is semi-rigidly joined, and the stress generated in the small-diameter RC column is reduced.
With this frame, there is no need to provide a separate horizontal resistance member as in the prior art, so the degree of freedom in building plan planning increases.

1 Building Structure 2 Small RC Column 21 Column Main Reinforcement (Tension Material for Prestress Introduction)
22 Sheath tube 23 for column main reinforcement Column shear reinforcement 3 Beam (becomes a bonding member or a pressure bonding member depending on the frame configuration)
31 Beam Main Bar 32 Beam Shear Reinforcement 33 Crimping PC Steel Strand 34 Crimping PC Steel Strand Wire 4 Semi-rigid Joint (Pin Joint)
41 Joining bar 42 Joining sheath sheath tube 43 Joining member 5 Column-to-beam joint 50 Column-to-beam crimping structure 6 Joint 7 Foundation beam (becomes a crimping joining member or joining member depending on the frame configuration)

Claims (4)

Diameter RC column is precast prestressed preparative concrete member, the bonding member such as a column base and the beam of the small diameter RC column is semirigid junction or pin junction,
Crimping Column Joints of stigma side and precast prestressed beams of said small-diameter RC column is formed so that the posts through, and installed in parallel with the substantially central height position of the beam-column joints Gahari Seiko A building structure with a frame crimped with PC steel strands. The small-diameter RC column is a precast prestressed concrete member, and the column base of the small-diameter RC column and a column beam joint such as a precast prestressed beam are formed to be a column-through, and the column beam joint is a beam. A building structure having a frame which is crimped by a crimping PC steel wire installed in parallel at a substantially central height position, and the head side of the small-diameter RC column and the precast prestressed beam are semi-rigidly joined or pin-joined . In the thin RC column, all main bars of the column are used as tendons,
The column beam joint is made of precast concrete, and is bonded to the small RC column with a PC steel material for crimping, thereby forming a frame that resists horizontal force, and by changing the degree of crimping, 3. The stress generated at one end of the small-diameter RC column is controlled by adjusting the separation moment and the post-separation rigidity so that the small-diameter RC column is not damaged. Building structure described in 1.   2. The semi-rigid joint is configured such that a joining bar is embedded in a substantially center of a cross section of the small-diameter RC column, and bending moment stress generated in the small-diameter RC column is reduced. The building structure described in any one of 3.