JP2004052389A - Panel zone constructing method and precast beam - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a panel zone constructing method which ensures the stability of the quality of hoops in a panel zone. <P>SOLUTION: (1) One beam member on which a screw nodal joint 40 is mounted at a mounting location of a first anchor reinforcement 23, is fixed to an upper bed 10a of a column member 10, as a primarily mounted beam member 20. (2) The other beam member 30 is fixed to the upper bed 10a of the column member such that the hoops 51, 52 which are temporarily fixed to a second lower anchor reinforcement 32a, are arranged on the periphery of extended portions of respective axial main reinforcements 11A to 12B of the column member. (3) The first anchor reinforcement is attached to the screw nodal joint on the primarily mounted beam member, and the temporarily fixed hoops are arranged at predetermined locations, respectively. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method of constructing a panel zone, which is a joint between a column member and a beam member, and in particular, on a top end surface of a reinforced concrete column member, a reinforced concrete beam formed as a separate body provided at an opposing position. The present invention relates to a method for constructing a panel zone for fixing members, and a precast beam (hereinafter, precast is referred to as “PCa”) used in the method.
[0002]
[Prior art]
2. Description of the Related Art In recent years, as a reinforced concrete structure (hereinafter, reinforced concrete is referred to as “RC”) has been raised in height, an RC laminated construction method has been implemented in order to construct a structure having an RC frame structure with high quality and rationally. In this RC laminating method, a plurality of RC columns are erected before a predetermined position, a PCa beam formed separately is fixed on the upper end surface, and a floor plate is erected between the PCa beams. In this method, cast-in-place concrete is applied to the upper surface of the floorboard and the panel zone, which is the joint between the RC column and the PCa beam, to form an integrated structure.
[0003]
In the panel zone in the RC laminating method, avoid the interference of the horizontal anchor reinforcing bars provided above and below the PCa beam, and surround the vertical axial main reinforcing bars (hereinafter, referred to as “vertical main reinforcing bars”) of the RC columns. It is necessary to arrange the hoop muscle.
For example, in the case where the left and right PCa beams are fixed on the upper end surface of the RC column, conventionally, both the left and right PCa beams are provided with the upper and lower anchor rebars. Using so-called split hoops formed by dividing into two, fixing the left and right PCa beams to RC columns, attaching the split hoops, and flaring the overlapped portion of the hoops as joints thereof. It was common to weld.
[0004]
[Problems to be solved by the invention]
However, the work of flare welding the split hoop streak is often performed in high places and in narrow places, and the welding posture of the operator and the torch during welding are likely to be unstable. However, there is a problem that the stability (reliability) of the product may remain uneasy.
In addition, since the flare welding work cannot be performed in rainy weather, there has been a problem that a delay in the work of arranging the hoop streak affects a delay in the entire construction period.
Furthermore, since the work of attaching the split hoop streak from the outer peripheral portion of the panel zone must be performed, there is a problem that the shape of the RC column in the panel zone and the series of construction procedures are restricted. .
[0005]
The present invention has been made in order to solve the above-mentioned problems, and it is possible to secure the stability of the quality of the hoop streak in the panel zone and to ensure the efficiency of work in the panel zone. It aims to provide a construction method for panel zones. Another object of the present invention is to provide a PCa beam used in the construction method.
[0006]
[Means for Solving the Problems]
In order to solve the above problems, the present invention includes the following steps, on the upper end face of a reinforced concrete column member, a reinforced concrete structure formed as a separate body provided at an opposed position. And a method for constructing a panel zone for fixing the beam member.
(1) A column member erection step in which the column member is erected in a state where an axial main reinforcing bar is extended to a predetermined height at an upper portion.
(2) A preceding beam member mounting step of fixing one of the beam members provided with a mechanical joint at a mounting position of a first anchor reinforcing bar on a side end surface of the column member side to an upper end surface of the reinforced concrete column member. .
(3) A state in which the other beam member having the second anchor reinforcing bar bent in the vertical direction is temporarily fixed to the second anchor reinforcing bar with a hoop bar having a closed cross section on the side end surface on the column member side. And fixing the hoop to the upper end surface of the reinforced concrete column member while disposing the hoop bar on the outer periphery of the extension of the main axial bar in the column member.
(4) The hoop for attaching the first anchor reinforcing bar to the mechanical joint of the preceding mounting beam member and arranging the temporarily fixed hoop bar at a predetermined position around the axial main reinforcing bar. Muscle arrangement process.
[0007]
Further, the present invention is a PCa beam for fixing on an upper end surface of a reinforced concrete column member, which is connected to an upper main reinforcing bar arranged on a beam main body, and from an end of the beam main body. An object of the present invention is to provide a PCa beam characterized in that a protruding anchor reinforcing bar is detachably formed so as to be able to be installed later.
Here, it is preferable to use a threaded reinforcing bar as the anchor reinforcing bar and to use a mechanical joint or a long nut so as to be detachable.
[0008]
Further, the column member may be made of RC, and may be applied to a full PCa column, a centrifugally formed hollow PCa column (PCF column), a cast-in-place RC column, and the like. Also, the beam member may be made of RC, and a full PCa beam, a half PCa beam, or the like can be used.
Further, it is necessary to provide the hoop rebar at the predetermined position where the hoop rebar exerts its action on the outer periphery of the extension of the axial main rebar.
For the mechanical joint, it is preferable to use a threaded joint such as a threaded joint or an end threaded joint, but a long nut may be used.
[0009]
In addition, this mechanical joint does not disturb the construction of the second anchor rebar and the hoop rebar of the other beam member to be installed later, and the first anchor rebar to the beam member to be constructed earlier by post-construction. What is necessary is just to be provided so that it can be attached. Therefore, it may be completely buried in the beam member to be constructed in advance, or may be provided so as to protrude from the end face portion by a predetermined length.
[0010]
In the present invention, the beam member to be constructed in advance is fixed to the column member in a state where the first anchor reinforcement is not attached, and the hoop reinforcement having a closed cross section is attached to the second anchor reinforcement of the beam member to be constructed later. Is temporarily fixed to the column member, and the first anchor reinforcing bar is attached to the beam member previously constructed via the mechanical joint. Therefore, since it is not necessary to perform flare welding or the like when arranging the hoop, the hoop can be constructed with high quality. In addition, since the hoop streak can be temporarily fixed to a beam member to be constructed later on the ground, work in high places can be reduced. can do.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described in detail with reference to the drawings.
In the following description, a PCa column and a Pca beam are used as the column member and the beam member, and are formed separately on the upper end surface of the PCa column at opposing positions on the left and right (see FIGS. 1 to 3). A method for constructing a panel zone for placing and fixing the PCa beam thus mounted will be described (reference numeral 1 indicates a panel zone).
[0012]
The method for constructing a panel zone according to the present invention comprises (1) a column member building step, (2) a preceding beam member placing step, (3) a trailing beam member placing step, and (4) a hoop rebar arrangement step. Have been.
[0013]
(1) Pillar Member Building Step This step is a step of performing an operation of erecting the Pca pillar 10, and can be performed by a known method (see FIG. 1A).
The PCa column 10 is provided with a plurality of vertical main reinforcing bars 11A to 12B protruding from the top end surfaces of the Pca beams 20 and 30 to be installed.
[0014]
(2) Preceding Beam Member Mounting Step In this step, the PCa pillar 20 (hereinafter, referred to as “preceding PCa beam”) on one side (the right side in FIG. 1B in this embodiment) precedes the PCa column. This is a step of performing the work of mounting and fixing the upper end face 10a on the right end of the upper end face 10a.
As shown in FIG. 4, a plurality of first upper main reinforcing bars 21 and first lower main reinforcing bars 22 are arranged in the beam main body of the preceding PCa beam 20 in the horizontal direction. The first lower main reinforcing bar 22 protrudes from the lower part of the side end surface 20a (left end surface) of the preceding PCa beam 20 on the PCa column 10 side, and is bent upward by about 90 degrees to form the first lower anchor reinforcing bar 22a. Have been.
[0015]
A threaded joint 40 is attached to an end of the first upper main reinforcing bar 21 (screwed bar) embedded in the concrete 25 forming the preceding PCa beam 20. As shown in FIG. 5, the threaded joint 40 includes a coupler 41 in which a screw portion 41a into which the first upper main reinforcing bar 21 and the first upper anchor reinforcing bar 23 are screwed is formed. And lock nuts 42 and 43 for fastening both reinforcing bars. In the threaded joint 40, one end 41b of the first upper main reinforcing bar 21 of the preceding PCa beam 20 is fastened to the coupler 41 by one lock nut 42, and the other end 41c of the coupler 41 is It is in an open state. The threaded joint 40 is buried in a state where a part of the coupler 41 protrudes from an upper portion of the side end face 20 a of the preceding PCa beam 20 on the PCa column 10 side.
As a result, the first upper anchor reinforcing bar 23 is detachable from the first upper main reinforcing bar 21 via the threaded joint 40, and is formed so as to be capable of post-installation.
[0016]
(3) Trailing Beam Member Placement Step In this step, the other (in the present embodiment, the left side in FIG. 2) PCa beam 30 (hereinafter, referred to as “trailing PCa beam”) is placed on the upper end surface of the PCa column 10. This is a step of performing an operation of placing and fixing the sheet 10a on the left end thereof.
On the succeeding PCa beam 30, a second upper main reinforcing bar and a second lower main reinforcing bar (not shown) are arranged in the horizontal direction. The second upper main reinforcing bar and the second lower main reinforcing bar project from the side end surface 30a (right end surface) of the succeeding PC beam 30 on the PCa column 10 side, and bend downward and upward by about 90 degrees, respectively. Thus, a second upper anchor reinforcing bar 31a and a second lower anchor reinforcing bar 32a are formed.
[0017]
In this step, the predetermined vertical main reinforcing bars 11A to 12B of the PCa column 10 extend while the plurality of hoop bars 51 and 52 are temporarily fixed to the second lower anchor reinforcing bar 32a of the succeeding PCa beam 20. The following PCa beam 30 is placed and fixed on the upper end face 10a of the PCa column 10 while the hoop streaks 51 and 52 are positioned so as to cover the outer periphery of the section.
The hoops 51, 52 are formed so as to have a substantially rectangular closed cross section, and the closed cross section is oriented in the same direction as the upper end surface 10a of the PCa column 10, and the hoops 51, 52 are formed. 52 so as to cover the outer periphery of the predetermined vertical main reinforcing bars 11A to 12B (in FIG. 3, the left inner vertical main reinforcing bar 12A, the right outer vertical main reinforcing bar 11A, the right inner vertical main reinforcing bar 11B, and the left outer vertical main reinforcing bar. (Two kinds of hoop streaks 51 and 52 are arranged so as to surround 12B).
[0018]
(4) Hoop Rebar Arrangement Step In this step, after attaching the first upper anchor reinforcement 23 to the threaded joint 40 of the preceding PCa beam 20 (see FIG. 3A), the periphery of the vertical main reinforcements 11A to 12B. Next, there is a step of arranging (mainly providing) the temporarily fixed hoop streaks 51 and 52 at predetermined intervals in the height direction (see FIG. 3B).
The first upper anchor rebar 23 is an L-shaped threaded rebar bent 90 degrees downward, and its end is inserted into the end 41 c of the coupler 41 of the threaded joint 40, and the lock nut 43 is inserted. Are joined by applying torque to them and tightening them.
[0019]
After this step, the PCa pillar 10 and the left and right PCa beams 20 and 30 are integrated by placing concrete (not shown) in the panel zone 1 and performing wet joining.
[0020]
As described above, in the panel zone construction method of the present invention, the preceding PCa beam 20 is fixed to the PCa column 10 in a state where the first anchor reinforcing bar 23 is not attached, and the second lower anchor reinforcing bar 32a has a closed cross section. With the hoops 51 and 52 temporarily fixed, the subsequent PCa beam 30 is fixed, and the separate first upper anchor reinforcing bar 23 is attached to the preceding PCa beam 20 via the screw joint 40. . Therefore, since it is not necessary to perform flare welding or the like when arranging the hoops 51, 52, the hoops 51, 52 can be constructed with high quality. In addition, since the work of attaching the hoops 51 and 52 is not affected by the weather, it is possible to prevent the work from being adversely affected on the prescribed construction period. Further, since the hoop streaks 51 and 52 can be temporarily fixed to the following PCa beam 30 on the ground portion, work at high places or the like can be reduced.
[0021]
Further, since the construction work is performed with the hoop streaks 51 and 52 temporarily fixed, work from the outer peripheral portion of the panel zone 1 does not occur, so that the structure of the work scaffold can be simplified and the PCa pillar 10 of the panel zone 1 can be simplified. It is possible to prevent the restriction of the shape of the (column member) and the series of construction steps.
[0022]
In the foregoing, an example of the preferred embodiment has been described for the present invention. However, the present invention is not limited to the above-described embodiment, and the design of each of the above-described components can be appropriately changed without departing from the spirit of the present invention.
In particular, in the above description, the two-way PCa beams provided at left and right opposing positions were described as beam members placed on the upper end surface of the column member. However, the present invention is also applicable to a case where the PCa beams are placed and fixed in four directions of left, right, up and down in plan view, and a case where the PCa beams are placed and fixed in three directions of left, right, up and down in plan view. It goes without saying that it can be applied.
Further, in the above embodiment, the PCa column is used as the column member, but another type of column member may be used. In addition, it is necessary to appropriately determine the structure of the mechanical joint, the type and size of the anchor reinforcing bar, and the like according to the application site.
Furthermore, there is no particular limitation on the mounting position of the anchor reinforcing bar in each beam member, its shape, and the like.
[0023]
【The invention's effect】
To provide a panel zone construction method capable of securing the stability of hoop streak quality in the panel zone and ensuring efficient work in the panel zone by using the PCa of the present invention. Can be.
[Brief description of the drawings]
1A and 1B are side views showing a panel zone construction method according to the present invention, wherein FIG. 1A shows a column member building process, and FIG. 1B shows a preceding beam member mounting process.
FIGS. 2A and 2B are side views showing a method for constructing a panel zone according to the present invention, and FIGS. 2A and 2B both show a subsequent beam member mounting step.
FIGS. 3A and 3B are side views showing a panel zone construction method according to the present invention, wherein both FIGS.
FIG. 4 is a side sectional view showing a preceding PCa beam of the present invention.
FIG. 5 is a side view of the threaded joint.
[Explanation of symbols]
1 Panel zone 10 Pca pillar (pillar member)
11A to 12B Vertical main reinforcing bar 20 Preceding PCa beam (one beam member)
21 First upper main reinforcing bar 22 First lower main reinforcing bar 22a First lower anchoring bar 23 First upper anchoring bar 40 Thread joint 41 Coupler 41b, 41c End 42, 43 Lock nut 30 Trailing PCa beam (the other beam) Element)
31a Second upper anchor reinforcing bar 32a Second lower anchor reinforcing bar 51, 52 Hoop bar

Claims (2)

Characterized by including the following steps,
A method of constructing a panel zone for fixing a reinforced concrete beam member formed at an opposite position on an upper end surface of a reinforced concrete column member.
(1) A column member erection step in which the column member is erected in a state where the main axial reinforcing bar is extended to a predetermined height at an upper portion.
(2) One of the beam members provided with a mechanical joint at a mounting position of the first anchor reinforcing bar on the side end surface on the column member side,
A step of placing the preceding beam member on the upper end surface of the reinforced concrete column member.
(3) The other beam member having the second anchor reinforcing bar bent in the vertical direction on the side end surface on the column member side,
In a state in which the hoop bar, which is a closed cross section, is temporarily fixed to the second anchor bar,
A subsequent beam member mounting step of fixing the hoop bar to an upper end surface of the reinforced concrete column member while arranging the hoop bar on an outer periphery of an extension of the main axial bar in the column member.
(4) The first anchor rebar is attached to the mechanical joint of the preceding mounting beam member,
A hoop rebar arrangement step of arranging the temporarily fixed hoop rebar at a predetermined position around the axial main rebar. A precast beam for fixing on the upper end surface of a reinforced concrete column member,
An anchor reinforcing bar connected to the upper main reinforcing bar arranged on the beam main body and protruding from an end of the beam main body is formed so as to be detachable so as to be able to be post-installed. Precast beams.

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