JPH08105114A - Connection method of column and beam - Google Patents

Abstract

PURPOSE: To use low strength concrete in a beam body by supporting beams on beam receives in such a state that the side end face of a beam is positioned at the edge of the column section and placing high strength concrete in the joint of the column and the beam. CONSTITUTION: Beam receives 14, 14 are fixed to respective opposite parts of the upper side faces of a column body 22 in a concrete column 12. And one end of beam bodies 16, 16 of precast concrete beams 10, 10 is placed on respective beam receives 14, 14 in such a way that the end faces thereof are positioned at the sectional edges of the column 12, at the joint of the column and the beams. Then a form defining at least the column-beam joint is arranged and high strength concrete is placed in the form. In this way, the concrete of the beam body 16 is made low in the strength than the column body 22, and the column 12 is not required to make excessively thick.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining at least a pair of beam members made of precast concrete and a column member made of concrete at a beam-column joint portion.

[Prior art]

In a high-rise reinforced concrete building, a method is adopted in which the columns are made of high-strength concrete, and the beams are made of low-strength concrete lower than the concrete for columns. This method is practiced both in constructions where concrete is cast on site and in constructions using precast concrete members.

Therefore, in a structure using a precast concrete beam member, a precast concrete beam member made of the same low-strength concrete is used over the entire length range of the beam main body, and both ends of the beam main body are adjacent to each other. The pillar and the beam are joined by placing them on the pillar main part of the matching pillar member and placing high-strength concrete for the pillar at the pillar-beam joint, which is the joint between the pillar and the beam. There is.

However, in the above-mentioned precast concrete beam member, since a part of the beam main body enters into the cross section of the column at the beam-column joint, even if high-strength concrete is used for the beam-column joint. , The effective cross-sectional area of the column at the beam-column joint becomes narrow. For this reason, when using conventional precast concrete beam members,
The building must be designed with the cross-sectional area corresponding to the barrage being structurally invalid, and the column becomes unnecessarily thick.

In order to solve the above problems, if the precast concrete beam member is made of the same high-strength concrete as the column concrete, a large amount of expensive high-strength concrete is required, and therefore the precast concrete beam member is expensive. become.

From the above, as described in Japanese Utility Model Laid-Open No. 4-42502, a precast concrete beam in which the middle part in the longitudinal direction is made of low strength concrete and both ends are made of high strength concrete. It is preferably a member. However, such a beam member is cumbersome to manufacture and the beam member itself becomes expensive.

Further, by simply placing one end of the precast concrete beam member made of concrete of different strength on the pillar main body of the pillar member, the upper surface of the pillar main body becomes a complicated uneven surface having many unevenness. Therefore, a gap is formed between the upper surface of the column main body and the lower surface of the beam main body. If concrete is placed in the beam-column joint with such a gap formed, the placed concrete will not be sufficiently filled in the gap between columns and beams, leaving a gap between the beams in the beam-column joint. .

[0008] In this way, if a space remains between the columns and beams of the beam-column joint, it is possible to regard the so-called interference portion corresponding to the area of the beam main body placed on the column main body as effective for the structure of the column. It must be treated as a so-called puffed concrete part that cannot be done, resulting in a smaller effective cross-sectional area of the structural columns. In order to prevent this, when trying to increase the substantial effective area of the column in the beam-column joint, the cross-sectional area itself of the column main body must be increased,
The pillars become unnecessarily thick.

As one of the methods of joining columns and beams, a pedestal is attached to each upper side surface of a square columnar column member, and one end portion of each column member is placed on the pedestal and four column member end portions are attached. It has been proposed to pour concrete into the beam-column joints formed inside (JP-A-6-173339).
However, in this method, since one end of each beam member is placed on the gantry and the upper surface of the column main body, it is inevitable that a gap remains between the column and the beam.

The above-mentioned publication also mounts a pedestal on each side in the middle of a column member such as a steel frame penetrating a beam-column joint, mounts one end of each column member on the pedestal, and attaches the four beam members. It describes that concrete is placed at the beam-column joints formed inside the ends. However, in this method, since the auxiliary rebar and the plurality of joints are required for connecting the pair of beam main bars, the number of parts and the number of joints required for connecting the pair of beam main bars are large, which is expensive.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent the need for unnecessarily thickening a column even though the concrete of the beam main part can be made a concrete having lower strength than the concrete of the column main part. Is to

[0012]

According to a method of joining a pillar and a beam of the present invention, a beam receiver is attached to each of opposite portions of an upper side surface of a pillar main body of a concrete pillar member, and each beam receiver is made of precast concrete. One end of the beam main part of the beam member is placed with its end face being the edge of the cross section of the column in the beam-column joint, and at least a formwork forming the beam-column joint is arranged, and at least the column-beam joint Including high-strength concrete.

The beam receiver is constructed by, for example, screwing a plurality of mounting bolts into screw holes provided in the upper portion of the pillar main body, or a plurality of anchors provided in the upper portion of the pillar main body. It is attached to the column main body by a bolt and an attachment nut screwed to the anchor bolt.

Each beam member is maintained in a state where the end surface on the side of the column member is the edge of the cross section of the column at the beam-column joint, and is not located within the cross-sectional area of the column at the beam-column joint. For this reason,
Even if there are no voids in the beam-column joints, and even if the beam main body is made of concrete with lower strength than the column main body, the columns of the column-beam joint are made of concrete of higher strength than the beam main body. It is formed. As a result, the area of the total cross-sectional area of the column in the beam-column joint can be regarded as an effective portion of the column structurally, and the effective area of the column in the beam-column joint becomes large.

As described above, according to the present invention, each beam member is supported by the beam receiver with the end surface on the side of the column member being the edge of the cross section of the column at the beam-column joining portion. Since the high-strength concrete is cast in the beam joint, the concrete of the beam main portion can be made to have lower strength than the concrete of the column main portion, but the column need not be unnecessarily thick.

The opposing beam main bars are preferably threaded grouts, threaded joints, mechanical joints such as sleeve joints, or welded prior to placing concrete, preferably prior to placing the formwork, preferably thread grouts or screws. It is connected by a screw type joint such as a joint.

The beam receiver may be, for example, a plate-shaped first portion that abuts the upper outer surface of the column main body and a plate-shaped second portion that extends substantially horizontally from the upper edge of the first portion. And a receiving member disposed in the pillar main body, and a vertical direction formed below the height position of the second portion and spaced in the width direction of the beam main body in the first portion. It is possible to use a device including a plurality of elongated holes.

[0018]

1 to 5, a pair of beam members 10 made of precast concrete and a column member 12 made of concrete are joined at a beam-column joint using a pair of beam receivers 14. .

Each beam member 10 includes a beam main body 16 having a rectangular column shape.
And a plurality of lower end streaks 18 extending in parallel through the lower part of the beam main body in the longitudinal direction, and a plurality of stirrup streaks 20 arranged at intervals in the longitudinal direction of the beam main body 16. Includes reinforced concrete beam members. Beam main body 16
At the end of the recess, a cotter 21
Are formed.

Each lower end reinforcement 18 is one of the beam main reinforcements, and also protrudes from both end faces of the beam main body 16. Beam main body 1
The length dimension of the protruding portion of the lower end streak 18 from 6 is preferably such that the lower end streak of the beam members facing each other in the beam-column joint can be connected to each other. The beam main body 16 may have a groove which is open on the upper surface thereof and extends in the longitudinal direction. Most of each stirrup streak 20 is embedded in the beam main body 16 with a part thereof protruding upward from the beam main body 16.

The column member 12 is composed of a columnar columnar main body 22 made of concrete, a plurality of column main bars 24 extending vertically from the column main body, and protruding further upward from the column main body 22. A plurality of hoop muscles (not shown) embedded in the pillar main body portion 22 at intervals in the direction,
It is a reinforced concrete pillar member. Each column main bar 24 extends beyond the beam-to-column joint and above the floor slab height position 26.

In the beam member 10, a plurality of lower end reinforcements 18 are arranged in a predetermined form in a predetermined form, and then concrete is poured into the formwork to a level at which the upper portion of each stirrup reinforcement 20 protrudes by a predetermined amount. It can be manufactured by solidifying. The pillar member 12 may be made of precast concrete or may be made of cast-in-place concrete.

As shown in FIGS. 3 and 4, each beam receiver 14 includes a receiving member 30 arranged on the pillar main body portion 22. The receiving member 30 includes an elongated plate-shaped first portion 32 that is in contact with the upper outer surface of the pillar main body portion 22, and an elongated plate-shaped second portion that extends substantially horizontally from the upper edge of the first portion. Three
4 and an elongated plate-shaped third portion 36 extending substantially horizontally from the lower end edge of the first portion 32 on the same side as the second portion 34.

The receiving member 30 has a substantially U-shaped cross section by the first, second and third portions 32, 34 and 36, and the ribs 38 are provided at a plurality of portions spaced in the longitudinal direction. It is reinforced by.

The beam receiver 14 also includes a second member of the receiving member 30.
A plurality of holes 40 formed at intervals in the longitudinal direction of the portion 34, a plurality of elongated holes 42 formed at a distance in the width direction of the receiving member 30 in the first portion 32, and a second Part 3
4, a plurality of nuts 44 fixed to 4, and a bolt 46 screwed into each nut 44 from the lower side of the second portion 34,
A thin plate 48 disposed on the upper end of each bolt 46.

Each hole 40 vertically penetrates the second portion 34. Each long hole 42 is a part of the first portion 32.
It penetrates a portion below the height position of the second portion 34 and is long in the vertical direction. Each plate 48 is rotatably attached to the tip of the bolt 46. The plate 48 is provided to prevent the beam member 10 from being damaged by the tip of the bolt 46. Therefore, the plate 48 may be provided on the beam member 10 or the plate 48 may not be provided.

Each nut 44 corresponds to the hole 40, and is fixed to the lower surface of the second portion 34 by welding or the like so that the axis matches the axis of the corresponding hole 40. Therefore, the female screw hole of each nut 44 acts as a through hole that vertically penetrates the second portion 34 together with the hole 40, and also acts as a female screw portion of the through hole. However, instead of providing the nut 44, the hole 40 itself may be a screw hole, or a female screw may be formed in a part of the hole 40.

In the beam receiver 14, mounting bolts 50 are passed through the elongated holes 42, and the bolts 50 are provided in the upper side surface of the pillar main body 22 at predetermined intervals in the width direction of the beam member 10 in advance. By being screwed onto 52, it is attached to the column main body 22 so as to extend in the horizontal direction. Each screw hole 52
Can be formed by embedding a female screw member such as a screw bush in the column main body portion 22.

When the pair of beam members 10 are joined at the column-beam joint, the pair of beam receivers 14 are attached to the opposite side surfaces of the column main body 22. At this time, in each beam receiver 14, the receiving member 30 is moved in the vertical direction with respect to the mounting bolt 50 to adjust the tightening position of the mounting bolt 50 with respect to the elongated hole 42, so that the upper surface of the receiving member 30 is mainly a pillar. The height position is adjusted so that the height position is almost the same as the upper surface of the portion 22.

The pair of beam members 10 to be joined have one end of the beam main body 16 mounted on the beam receiver 14 arranged so as to face the upper outer surface of the column main body 22. The other end of each beam member 10 is placed on a beam receiver provided on another column member. Each beam receiver 14 receives the lower surface of the beam member 10 on the plate 48 at the upper end of the height adjusting bolt 46. At this time, each beam member 10 is in a state in which the end surface of the beam main body 16 is the edge of the cross section of the column in the beam-column joint, that is, the end surface of the beam main body 16 is the first of the column main body 22 and the beam receiver 14. It is placed on the beam receiver 14 so as to be substantially coincident with the boundary surface of the first part 32.
However, the other end of the beam member 10 may be supported by a column or the like.

In the above state, each bolt 46 for height adjustment
The height position of the beam member 10 is adjusted (see FIG. 3) so that the axis lines of the lower end streak 18 to be connected with each other are adjusted by adjusting the screwing amount of the lower end streak 18 with the same axial line.
The ends of are joined together in a one-to-one fashion by mechanical joints 54 in the beam-column joint. In this way, if the lower end reinforcements 18 to be joined are aligned with each other by the mechanical joint 54 in a state where the axes of the lower end reinforcements 18 are aligned,
A mechanical joint such as a screw grout, a screw joint, and a sleeve joint, particularly, a screw joint can be used for easy connection.

Next, a plurality of upper end streaks (not shown) are passed through the stirrup streak 20 from one beam member 10 side to the other beam member side, and are arranged above the both beam members.
Floor rebars are placed in the casting space for the floor slabs, additional hoop or stirrup bars are placed at the beam-column joints, and a given formwork (not shown) is placed in a given condition. It

Prior to or after placement of the formwork,
As the bolts 46 for adjusting the height of the beam receiver 14 are unscrewed, each beam member 10 is placed on the receiving member 30 at one end of the beam main body 16 as shown in FIG. Even in this state, each beam member 10 is maintained in a state in which the end surface of the beam main body portion 16 becomes the edge portion of the cross section of the column in the column beam joint.

Thereafter, concrete is poured into the beam-column joint, the casting space for the floor slab, and the remaining casting space above the beam member 10. Accordingly, the concrete of the beam main body 16 and the column main body 22 is directly integrated with the concrete of the beam-column joint, the concrete of the remaining casting space above the beam member 10, and the concrete for the floor slab. To be joined to.

The concrete cast at least in the beam-column joint is a concrete having a higher strength than the concrete of the beam main body 16, preferably, a concrete having the same strength as the concrete of the beam main body 22.

As described above, each beam member 10 is connected to the column member 12
If the high-strength concrete is placed in the beam-column joint with the end surface on the side of the column-beam joint being supported by the beam receiver 14 in a state where it becomes the edge of the cross-section of the column in the beam-column joint, No void is formed, and even if the beam main body 16 is the pillar main body 2
Even if it is made of concrete having a strength lower than 2, the portion of the pillar in the beam-column joint is made of high strength concrete.

As a result of the above, the area of the total cross-sectional area of the column in the beam-column joint can be regarded as an effective portion of the column structurally, and the effective area of the column in the beam-column joint becomes large. Although it is possible to use the above concrete with lower strength than the concrete of the column main body, it is not necessary to unnecessarily thicken the column.

Each beam receiver 14 is removed at an arbitrary time after the concrete is solidified. Each beam receiver 14 can be removed by removing the mounting bolt 50. At this time, since the mounting bolts 50 are passed through the elongated holes 42 extending in the vertical direction, by releasing the tightening by the mounting bolts 50, the receiving member 30 moves downward by its own weight and the beam receiving 14 is separated from the beam member 10 to facilitate the work of removing the beam receiver 14.

Instead of attaching the beam receiver 14 to the pillar member 12 with the bolt 50 and the screw hole 52, the pillar main body portion 22 is used.
May be attached to the column member 12 by a plurality of anchor bolts provided in advance on the upper part of the above and an attachment nut screwed to each anchor bolt. Each anchor bolt is provided on the pillar main body so as to project substantially horizontally from the upper side surface of the pillar main body.

When using anchor bolts and nuts,
The beam receiver 14 is attached to the pillar main body by inserting an anchor bolt provided in the pillar main body into the elongated hole and screwing a nut on each anchor bolt. Also in this case, the beam receiver can be removed by removing the nut. Also, since the anchor bolt is passed through the elongated hole that extends in the vertical direction, by releasing the tightening with the nut, the receiving member moves downward, the beam receiver is separated from the beam member, and the beam receiver can be removed. It will be easier.

When a sleeve joint, welding or the like is used as a means for joining the opposing lower end ribs 18, that is, when it is not necessary to adjust the height of the opposing beam member 10, the height adjusting bolt 46 is not provided. May be.

When the beams are crossed at the beam-column joints in a cross shape, first, as shown in FIG.
Is attached to the outer surface of the upper portion of the pillar main body 22. Then
A pair of beams which are placed on the beam receiver 14 so that the ends of the pair of beam members 10 are opposed to each other, and the lower end streaks 18 which are opposed to each other are coupled by a joint 54, and then the other pair of beam members 14 are arranged in advance. The member 10 and the beam-column joint are placed on the beam receiver so as to intersect in a cross shape and face each other, and the lower end ribs 18 which face each other are joined by the joint 54, and then the upper end ribs are arranged.

If the cotter 21 is provided on the end face of the beam main body 16 as in the above-described embodiment, a part of the concrete cast at the beam-column joint portion enters the cotter 21,
The beam main body 16 is firmly integrated with the beam-column joint. However, such a cotter 21 may not be provided on the end surface of the beam main body 16.

Similarly, a groove which is open on the upper surface of the beam member and extends in the longitudinal direction of the column member may be formed in the beam member. In this way, after the beam member is assembled to the beam-column joint, by placing concrete for the floor slab, part of the concrete enters the groove and solidifies, so that the beam member and the floor slab The relative positional relationship of is maintained.

The present invention is not limited to the above embodiment. For example, the present invention can be applied to a beam member having a semicircular cross-sectional shape, and can also be applied to a column member having a circular cross-sectional shape. Further, instead of removing the beam receiver after the concrete is solidified, the beam receiver may be left in a buried state in the concrete depending on the type and shape of the formwork.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a beam-column joining portion for explaining a joining method of the present invention, and is a front view showing a state where a pair of beam members are joined at an upper portion of the column member.

FIG. 2 is a plan view of FIG.

3 is an enlarged front view showing the vicinity of the beam receiver in FIG. 1, and is a front view showing a state in which height adjustment is performed.

FIG. 4 is a side view showing the vicinity of the beam receiver in FIG. 1 in an enlarged manner.

FIG. 5 is a plan view showing an embodiment in which beams are crossed in a cross shape.

[Explanation of symbols]

 10 Beam member 12 Column member 14 Beam receiver 16 Beam main part 18 Lower end bar 22 Column main part 24 Column main bar

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomoaki Tsujimura 2-1, Tsukudocho, Shinjuku-ku, Tokyo Kumagai Gumi Tokyo Head Office

Claims (1)

[Claims] 1. A method for joining at least a pair of beam members made of precast concrete having a beam main body and a concrete column member having a column main body at a beam-column joint above the column main body. , A beam receiver is attached to each of the facing portions of the upper side surface of the pillar main body,
One end of the beam main body is placed on each beam receiver with its end face being an edge of a cross section of a column in the column-beam joint, and at least a form forming the column-beam joint is arranged, A method for joining columns and beams, which includes placing high-strength concrete at the beam-column joints.