JPH02194226A - Jointing method for precast concrete pillar with pillar beam - Google Patents

Abstract

PURPOSE:To have simple and certain execution of works and increase the strength of a pillar/beam junction part by installing an upper and a lower beam main rod in the beam joint position of a hollow PC pillar, in which a pillar main rod and a shear reinforcing rod are incorporated, in such a way that one end of each rod is protruding from the pillar surface. CONSTITUTION:An upper beam main rod 6 and a lower beam main rod 6' at whose one end a fixation part is formed by bending process are inserted in a beam main rod insert hole 5, which accommodates a pillar main rod 1 and a shear reinforcing rod 3 and is provided in a panel zone of a hollow PC- pillar A having a hollow 4, wherein the insert hole 5 is in communication with the hollow 4, in such a manner of insertion that their other ends are protruding. The PC-pillar A is put upright at site and a semi-PC beam B is placed, and the beam bottom rod 7 of this beam B and the beam top rod 8 of placed-in-site rod are welded W with the lower beam main rod 6' and upper beam main rod 6, respectively. After a stirrup 9 and a form are fixed, concretes C, C' are placed in the beam joint part and the hollow 4 so as to joint together the PC pillar/beam A, B.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method for joining a precast concrete column (hereinafter referred to as a PC column) and a semi-precast concrete beam (hereinafter referred to as a semi-PC beam), and a method used in the same method. This is related to the PC pillar.

(Conventional technology) Conventionally, PC columns were manufactured from the column base to the bottom end of the beam in a factory and erected on site, and concrete was not poured into the panel zone part of the column head of the PC column. After installing PC beams connected only by beam reinforcements and arranging shear reinforcing bars in the panel zone, the outer formwork for forming the panel zone was installed and concrete was poured.

At this time, the main beam reinforcements of the PC beams were joined by welding at the center of adjacent PC column surfaces.

Alternatively, the ends of a PC beam with beam bottom reinforcements protruding from both ends of the beam are placed on the head of a PC column, the reinforcement within the panel zone is arranged on site, the formwork for forming the panel zone is installed, and the concrete is placed. The columns and beams were connected by pouring.

(Problem to be solved by the invention) However, the former has the following problems.

(i) It is difficult to arrange shear reinforcing bars within the panel zone.

(!:) When placing concrete in the panel zone, it is difficult to place concrete densely enough because the equipment and direction of concrete placement are limited at the site.

(iii) The outer formwork forming the panel zone is 4 of the columns.
It is difficult to fix the formwork because it is only at the corner.

(iv) When welding the main reinforcements of PC beams from both sides at the center of adjacent PC column faces, since the beam main reinforcements are cast into concrete, thermal stress due to welding remains and the structure It has a negative effect on the body.

In the latter case, in addition to the problems (i) to (iii) above, there are the following problems.

(V) It is difficult to secure the anchorage length for the beam main reinforcement only within the panel zone.

The present invention has been proposed in view of the problems of the prior art, and its objectives are to provide a method for joining PC columns and beams that is easy and reliable in construction and has high structural reliability;
and to provide PC pillars that can be applied to the same construction method.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the method for joining PC columns and beams according to the present invention includes a method for joining studs in the panel zone of a hollow precast concrete column that incorporates main reinforcement and shear reinforcement. A beam main reinforcement insertion hole that communicates with the hollow part is provided, and the upper and lower beam main reinforcements are inserted into the parallel main reinforcement insertion holes so that their ends protrude from the column surface, and the columns are erected at a predetermined position, and then the semi-precast concrete beam is inserted. After joining the protruding ends of the lower beam reinforcement and the upper beam reinforcement from the column surface, the protruding end of the beam lower end reinforcement of the beam, and the beam upper reinforcement installed on site, This method is characterized in that joint concrete is placed in the joints of the beam reinforcements and in the hollow parts of the columns.

In this case, in order to increase the fixing force of the panel zone at the ends of the upper and lower beam main reinforcements, it is desirable that the fixing ends be curved.

Furthermore, in order to smoothly carry out the joining method of the PC columns and beams,
The PC column according to the present invention has a hollow hole in the center of the cross section of the column, and the beam main reinforcement insertion hole communicating with the hollow hole is provided in the panel zone portion.

(Function) According to the present invention, a hollow PC is provided with built-in main reinforcements and shear reinforcing bars, and in which upper and lower beam main reinforcements are inserted into beam main reinforcement insertion holes provided in the panel zone so that their ends protrude from the column surface.
A column is erected at a predetermined position, and then a half-PC beam is erected, and a beam bottom end reinforcement that protrudes from the end of the beam and a beam top end reinforcement that is installed on site are respectively made to protrude from the column surface of the PC column. By joining the main reinforcing bars and the upper main beam reinforcing bars and pouring concrete into the joints of each of the beam reinforcing bars and the hollow parts of the PC columns, the PC column beam joints are secured with sufficient anchorage length for the beam main reinforcing bars. Configure. At this time, since the beam main reinforcement inserted in the panel zone is not fixed, no stress due to thermal strain remains even if the beam is joined by welding to the beam lower end main reinforcement of the semi-PC beam.

(Example) The present invention will be described below with reference to the illustrated embodiments.

The prisoner is a hollow PC pillar, and its length is equal to the height of one floor from the top of the floor to the top of the upper floor.

Attach joint hardware such as splice sleeves (2) to the legs of the column main reinforcement (1), set it in the PC column mold so that the column main reinforcement (1) protrudes at the column head, and attach the column main reinforcement (1)
Arrange the required shear reinforcing bars (3). Also, install the formwork material for forming the opening for inserting the beam main reinforcement in the panel zone in the specified position.

As mentioned above, concrete is poured into the formwork with the specified reinforcement, joint hardware, and formwork materials arranged, and the formwork is rotated to perform centrifugal compaction, creating a hollow in the center of the column cross section. (4
) and is provided with a beam main reinforcement insertion hole (5) that communicates with the hollow part (4) in the panel zone.

Opposing main beam reinforcement insertion hole (4) in the hollow PC column
The upper beam main reinforcement (6) has a fixed part bent at one end.
and the lower beam main reinforcement (6') are inserted so that the other end protrudes from the column surface, and the PCl3 (A) in this state is erected on site, then the half-PC beam (marked) is erected, and the same beam (B Beam bottom reinforcement (7) protruding from the end and beam top reinforcement (8) placed on-site.
are welded and connected to the lower beam main reinforcement (6') and the upper beam main reinforcement (6), respectively. In the figure, (b) shows this welded joint. At this time, the beam main reinforcing bars (6) (6'l) inserted in the panel zone are not buried in concrete, so there is no thermal distortion due to welding. There is no residual thermal stress.

Note that a pressure welding method may be adopted for joining the beam reinforcements.

Next, after attaching the stirrup bars (9) and formwork at the beam joint, the beam joint and the hollow section (3) of the PC column (2) are installed.
Concrete (c) (c') is poured into the concrete and the PC columns and beams are connected. Note that in the figure, 0 indicates temporary support.

(Effects of the Invention) According to the present invention, as described above, the ends of the upper and lower beam main reinforcements are inserted into the beam main reinforcement insertion holes that communicate with the hollow part provided in the panel zone of the studs, so that the ends of the hollow PC columns protrude from the column surface. Then, a half-PC beam is erected, the end protrusion of the lower beam main reinforcement of the beam is connected to the lower beam main reinforcement, and the reinforcement is arranged on site. By joining the beam upper end reinforcement and the upper beam main reinforcement, and placing joint concrete in the joint of each beam reinforcement and the hollow part of the PC column,
PC columns and beams are joined together, and in this case, it is easy to secure the fixing length of the main beam reinforcement, and the strength of the joint between the columns and beams is improved.

Furthermore, since the complicated reinforcing bars in the panel zone are not carried out on-site but in the factory, the reinforcing bars are reliably fitted.

Furthermore, since the main beam reinforcing bars inserted in the panel zone are not fixed, no stress due to thermal strain remains even if they are joined by welding to the beam bottom reinforcing bars of the semi-PC beam.

Furthermore, as mentioned above, since the beam main reinforcement inserted in the panel zone is not fixed, the position can be freely adjusted to match the lower end beam main reinforcement embedded in the semi-PC beam, making construction easier. can.

According to the second aspect of the present invention, the fixing force of the main beam reinforcement to the panel zone is increased by curving an anchoring portion at the end of the main beam reinforcement.

The invention of claim 3 provides a hollow hole in the center of the column cross section of the PC column, and a beam main reinforcement insertion hole communicating with the hollow hole in the panel zone part, and facilitates the PC column beam joining method using the PC column. It is Uruchino who will carry out the work.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing the implementation status of one embodiment of the precast concrete column and beam joining method according to the present invention, Fig. 2 is a longitudinal sectional view of the precast concrete column, and Fig. 3 is its transverse plan view. FIG. 4 is a perspective view thereof. Prisoner... PC column, (c) (c') - Concrete, (3) - m- Shear reinforcement, (5) - Main reinforcement insertion hole, (6') - Lower beam main reinforcement, (7).・・Lower end beam main reinforcement of half-PC beam, (8)−・Beam upper end reinforcement. (Seal: Half-PC beam, (1)-11 main reinforcement, (4)-m-hollow section, (6)--1 section beam main reinforcement, Agent: Patent attorney Shige Okamoto, 2 other people

Claims (3)

[Claims] (1) In the panel zone of a hollow precast concrete column containing column main reinforcement and shear reinforcing bars, provide a beam main reinforcement insertion hole that communicates with the hollow part of the column, and insert upper and lower beam main reinforcement into the beam main reinforcement insertion hole so that the ends of the upper and lower beam main reinforcements are respectively The column is inserted so as to protrude from the column surface, and the column is erected at a predetermined position, and then a semi-precast concrete beam is erected, and each of the protruding ends of the lower beam reinforcement and the upper beam reinforcement from the column surface and the beam A precast characterized in that, after the protruding end of the beam bottom reinforcement and the beam top reinforcement installed on site are joined, joint concrete is poured into the joint of each of the beam reinforcements and the hollow part of the column. Connection method for concrete columns and beams. (2) The method for joining precast concrete columns and beams according to claim 1, wherein fixed ends are curved at the ends of the main reinforcements of the upper and lower beams. (3) A precast concrete column having a hollow hole in the center of the cross section of the column, and a beam main reinforcement insertion hole communicating with the hollow hole in the panel zone.