JPH04237731A - Constructing method for rc pillar with core reinforcement bar - Google Patents

Abstract

PURPOSE:To enhance the effectiveness in execution of works and simplify the procedure in constructing pillars in the substratum part of a multi-storey building of ferro-concrete, wherein the substratum part includes a core steel reinforcement. CONSTITUTION:The sheath part of each pillar is formed from a precast pillar member B due to centrifugal molding having built-in pillar main rods 2, which are equipped with sleeve joint 1, and a core steel reinforcement A is formed from mild steel rods preassembled at site. This core steel reinforcement A is joined with another core steel reinforcement C in the substratum part, and the precast pillar member B is fitted. Through the sleeve joint 1, the pillar main rods 2 of this precast pillar member B are joined with pillat main rods D of the substratum part, and concrete 6 is placed in the hollow of the precast pillar member B.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention applies to high-rise reinforced concrete (
(hereinafter referred to as RC) relates to a partial precast column construction method with core reinforcing bars that is applied to the construction of the lower floors of buildings.

0002

BACKGROUND OF THE INVENTION Columns applied to the lower floors of high-rise RC buildings are more complex to construct than columns of ordinary buildings. Figures 8 to 11 show the conventional on-site construction process of the column part, and the main reinforcement of the column a
The core reinforcing bars b are welded to the lower reinforcing bars c, the core hoop reinforcements d are reinforced to the bottom of the beam, the hoop reinforcements e are reinforced to the bottom of the beam, and the column formwork f is installed to form the beam. Pour concrete to the bottom edge. (See Figures 8 and 9) In the case of the pre-assembled method,
Column main reinforcement a and hoop reinforcement e, core reinforcement b and core hoop reinforcement d
are pre-assembled, the pre-assembled reinforcing bars g are placed in a predetermined position by a crane, and welded to the lower reinforcing bars c,
Install formwork f for the column part and pour concrete up to the bottom end of the beam. (See Figure 9) After concrete is poured to the bottom end of the beam, reinforcement is placed at the beam joint and slab reinforcement, and concrete is poured. (See FIG. 8) In the figure, h is a beam and i is a slab.

FIGS. 12 to 15 show the construction process of a conventional precast column.
is installed in a predetermined position, the lower reinforcing bar c is inserted into the sleeve joint, grout mortar is injected, and the main reinforcing bar a of the precast column k and the lower reinforcing bar c are joined, as in the previous case. Next, the joints with the beams and slab reinforcements will be placed and concrete will be placed.

0004

[Problem to be solved by the invention] However, the above-mentioned FIG.
In the case of on-site reinforcement shown in Figures 11 to 11, high-rise RC buildings use larger-diameter reinforcing bars than conventional RC buildings, and hoop reinforcement is densely arranged, so it takes less time to arrange and assemble reinforcing bars. Also, because the reinforcing bars are densely arranged, concrete placement becomes difficult.

Furthermore, in the case of the precast columns shown in FIGS. 12 to 15, since the core reinforcing bars are placed inside the main reinforcement, it is difficult to inject grout into the sleeves of the core reinforcing bar column legs, and it is difficult to confirm the grouting status. Have difficulty. The present invention has been proposed in view of the problems of the prior art, and aims to improve construction efficiency, save labor, and provide high-rise buildings with core reinforcing bars that are structurally highly reliable. The object of the present invention is to provide a method for constructing RC columns in the lower part of a building.

[0006]

[Means for Solving the Problems] In order to solve the above object, a method for constructing an RC column having core reinforcing bars according to the present invention includes:
In a method for constructing a reinforced concrete column having a core reinforcing bar on the lower floor of a high-rise reinforced concrete structure, the outer shell part of the column is a centrifugally formed precast column member containing a main column reinforcement with a sleeve joint attached to the end of the column base, and The core reinforcing bar part is used as the on-site assembly reinforcing bar, the concentric reinforcing bar is joined to the core reinforcing bar in the lower layer, and then the precast column member is inserted into the concentric reinforcing bar, and the main column reinforcement of the column member is attached to the lower layer through the sleeve joint. This involves pouring and filling concrete into the hollow part of the column member after joining it to the main column reinforcement of the column member.

[0007]

[Operation] According to the present invention, as described above, the outer shell portion of an RC column having a core reinforcing bar is composed of a centrifugally formed precast column member containing a column main reinforcement with a sleeve joint attached to the end of the column base. At the same time, the core reinforcing bars are made into field-assembled reinforcing bars, and the concentric reinforcing bars are connected to the core reinforcing bars in the lower layer, and then the hollow part of the centrifugally formed precast column member is fitted to the core reinforcing bars, and the main column reinforcement of the precast column member is are joined through a sleeve joint, and then concrete is cast and filled into the hollow part of the precast column member, thereby constructing an RC column in which the core reinforcing bar is integrally incorporated.

[0008]

[Embodiment] A is a pre-assembled core reinforcing bar, and B is a centrifugally formed precast column member, which incorporates a column main reinforcement 2 with a sleeve joint 1 attached to the end of the column base. C and D are core reinforcing bars and column main reinforcing bars that protrude from the lower layer. After erecting the pre-assembled core reinforcing bars A and welding them to the core reinforcing bars C in the lower layer, the center part of the precast column member B is fitted to the outer periphery of the core reinforcing bars A and C (Figs. 2 and FIG. 5) Connect the column main reinforcement 2 of the precast column member B to the column main reinforcement D in the lower layer via the sleeve joint 1 and the grout mortar injected into the sleeve joint 1, and connect the precast beam E to the precast column reinforcement 2. Hoop reinforcement 3 at the column-beam joint by installing it on the capital of column member B
, arrange the formwork 5 and slab formwork at the same joint, and arrange the beam upper end reinforcements 4 and slab reinforcements. (See FIGS. 3 and 6) Next, concrete 6 is poured into the hollow portion of the precast column member B sequentially from the column base, and the column-beam joint and the slab are simultaneously poured with concrete. (See Figures 4 and 7)

[0009]

According to the present invention, as described above, the column outer shell portion is composed of a centrifugally molded precast column member containing a column main reinforcement with a sleeve joint attached to the column base end,
The core reinforcing bar part is composed of pre-assembled reinforcing bars on site, and the concentric reinforcing bars are joined to the core reinforcing bars in the lower layer, and then the hollow part of the centrifugally formed precast column member is fitted into the core reinforcing bars, and the core reinforcing bars are inserted through the sleeve joint. The main column reinforcement of the precast column member and the main column reinforcement of the lower layer are connected, and then concrete is poured into the hollow part of the column member to construct an RC column in which the column member and the core reinforcing bar are integrated. As a result, reinforcing steel work is shortened, formwork work is reduced, and workability is improved. Furthermore, since the core reinforcing bars are constructed on-site, the joints of the main reinforcements are welded together, making construction easier than when using the conventional precast columns.

Furthermore, according to the present invention, most of the columns are manufactured in a factory, and the quality of the concrete can be maintained constant. Furthermore, by devising the details of the beam main reinforcement, it is possible to change the core reinforcing bar portion to a core steel frame.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing a first step of an embodiment of a method for constructing an RC column having a core reinforcing bar according to the present invention.

FIG. 2 is a longitudinal sectional view showing a second step of the present invention.

FIG. 3 is a longitudinal cross-sectional view showing the third step of the present invention.

FIG. 4 is a longitudinal sectional view showing a fourth step of the present invention.

FIG. 5 is a view taken along the arrow A--A in FIG. 2;

FIG. 6 is a rolling diagram in the direction of the arrows in FIG. 3;

FIG. 7 is a plan view of FIG. 4;

FIG. 8 is a longitudinal cross-sectional view showing an example of a conventional construction method.

FIG. 9 is a longitudinal sectional view showing the implementation status of another example of the conventional construction method.

FIG. 10 is a longitudinal cross-sectional view showing a state in which reinforcement of a column portion has been completed using a conventional construction method.

FIG. 11 is a cross-sectional plan view of FIG. 10;

FIG. 12 is a longitudinal sectional view showing the first step of another example of the conventional construction method.

FIG. 13 is a longitudinal sectional view showing the second step of the conventional construction method.

FIG. 14 is a longitudinal sectional view showing the third step of the conventional construction method.

FIG. 15 is a cross-sectional plan view of FIG. 13;

[Explanation of symbols]

A Core reinforcing bar B Centrifugally formed concrete column member C Lower core reinforcing bar D　Lower column main reinforcement 1 Sleeve joint 2 Column main reinforcement 6. Concrete

Claims (1)

[Claims] Claim 1: A method for constructing a reinforced concrete column with a core reinforcing bar on the lower floor of a high-rise reinforced concrete structure, in which the outer shell of the column is a centrifugally formed precast column with a built-in column main reinforcement with a sleeve joint attached to the end of the column base. In addition to using it as a member, the core reinforcing bar part is used as an on-site assembly reinforcing bar,
After joining the concentric reinforcing bars to the core reinforcing bars in the lower layer, then inserting the precast column member into the concentric reinforcing bars and joining the main column reinforcing bars of the column member to the main column reinforcing bars in the lower layer via the sleeve joint, pouring concrete into the hollow part of the column member;
A method for constructing an RC column having a core reinforcing bar characterized by filling.