JPS62242053A - Construction method of precast reinforced concrete pillar - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of constructing a precast reinforced concrete column.

(Prior technology) Four or more large-diameter deformed reinforcing bars that will become the main reinforcing bars of a structure's columns are planted, and steel pipe sheaths that run vertically through the entire length of the columns are buried in corresponding positions of each reinforcing bar in the cross section of the column. A precast reinforced concrete in which a precast reinforced concrete column is dropped from above the large-diameter irregularly shaped reinforcing bars so that each of the reinforcing bars fits into each of the sheaths, and high-strength expansion mortar is injected and filled into the gap between each of the sheaths and each of the reinforcing bars. A method for constructing columns is proposed in Japanese Patent Publication No. 51-2724.

(Problems to be Solved by the Invention) In the conventional construction method, for each of the main reinforcing bars of the column planted from the lower structure, a sheath with a small cross section into which the reinforcing bars should be inserted is buried in the PC column. Therefore, it is not easy to insert the PC column into the column main reinforcement, and the gap between the inside of the sheath and the column main reinforcement is small, making it difficult to fill with grout.
Furthermore, since the sheath is fitted to the first half of the main column reinforcing bar, there are many places to fill with grout, which requires a lot of effort and time for construction.

(Means for Solving the Problems) The present invention was proposed to solve these problems, and in the section of the column where the main reinforcement bars are arranged,
A PC column, in which a sheath that bundles and envelops a plurality of column main reinforcing bars and is buried vertically through the column, is dropped from the top of the stockholder reinforcing bars that have been planted from the lower structure, and the above-mentioned After a sheath is fitted, the gap between the sheath and the shareholder reinforcing steel is filled with concrete or grout.The purpose of this is to use precast reinforced concrete, which has excellent workability and high structural reliability. The point is that it provides a method for constructing columns.

(Function) As described above, in the present invention, a sheath column with a large cross section that can bundle and envelop a plurality of shareholder reinforcing bars is buried vertically in the section of the column where the shareholder reinforcing bars are arranged, thereby forming a PC column. The PC column is dropped from the upper part of the stockholder reinforcing bars planted from the lower structure, and a plurality of column main bars are fitted into each of the sheaths.

At this time, since the sheath has a large cross section that can bundle and envelop a plurality of shareholder reinforcing bars, the P with respect to the shareholder reinforcing bars is
The C pillar can be easily lowered.

In this way, after the PC column is dropped into the shareholder reinforcing bar, the gap between the sheath and the shareholder reinforcing bar fitted into the sheath is filled with concrete or grout to integrate the PC column and the shareholder reinforcing bar, At this time, since a relatively large gap is formed between the sheath having a large cross section and the column reinforcing bars, filling with concrete or grout is easily performed.

In the reinforced concrete column constructed in this manner, the shareholder reinforcing bars are restrained by the sheath, so buckling is prevented when a load is applied.

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

(N is a PC column, which is made of steel with multiple shareholder reinforcing bars bundled and wrapped around each part in the section of the concrete column body (1) where the shareholder reinforcing bars are to be placed inside the column reinforcement (2). A sheath (3) is embedded through the pillar body (1) at a distance Ff1.

The sheath (3) may be formed to have a rectangular cross section as shown in FIG. 1, a triangular cross section as shown in FIG. 3, or any other arbitrary cross section.

In the figure (4) is a crack prevention line.

Then, at the position of the sheath (3) of the PC column (A)K, the stockholder reinforcing bar (5) is planted from the lower structure, for example, the floor (B) as shown in the figure, and the stockholder reinforcing bar (5) is placed above the stockholder reinforcing bar (5). Lower the PC column (A) and insert a plurality of shareholder reinforcing bars (5) into each sheath (3) of the stud, and then insert each sheath (3)
) is filled with concrete (6) or grout to integrate the stockholder reinforcing bars (5) and the PC column (gradient).

In the figure, (C) is a PC beam or cast-in-place concrete beam spanned over the PC column (A), and Q) is cast-in-place concrete placed between the column head and the beam.

According to the illustrated embodiment, as described above, a sheath (3) with a large cross section that bundles and envelops a plurality of passing iron a (5) is embedded in the PC column (A), so that the passing reinforcing steel PC pillars (3
) can be easily dropped into the sheath (3), and filling the inside of the sheath (3) with concrete (6) or grout is also easy, and the number of filling locations is also reduced.

Furthermore, since the sheath (3) directly restrains the shareholder reinforcing bars (5), buckling of the shareholder reinforcing bars (5) is prevented.

In addition, high-strength concrete (6) is placed inside the sheath (3).
Or by filling with grout, shareholder reinforcing steel (5
) and the sheath (3),
At this time, it is possible to fill with concrete (6) or grout even if the minimum spacing between the shareholder reinforcing bars (5) is smaller than usual.

Furthermore, by using a wire mesh-like member as the sheath (3), the integrity of the concrete column body (1) of the PC column (N) and the concrete (6) or mortar inside the sheath (3) is strengthened.

Although the present invention has been described above with reference to embodiments, the present invention is of course not limited to such embodiments, and the seed design may be modified without departing from the spirit of the present invention. be.

(Effects of the Invention) According to the present invention, as described above, in the section K of the cross section of the PC column where shareholder reinforcing bars are arranged, a sheath with a large cross section that can bundle and envelop a plurality of shareholder reinforcing bars runs longitudinally through the column [ Since the PC column is buried, it is easier to lower the PC column from the top of the column main reinforcing bar that is planted from the lower structure, compared to the conventional case where a one-piece sheath is placed for each passing reinforcing bar. In addition, the gap between the sheath and the group of shareholder reinforcing bars within the same sheath is larger than in the conventional case, making it easier to fill the sheath with concrete or grout, and there are fewer places to fill, improving workability and shortening the construction period. be shortened.

In addition, as mentioned above, since the gap between the sheath and the shareholder reinforcing bars in the same sheath is large, the concrete or mortar filled in the sheath adheres sufficiently to the main reinforcing bars of the column, and the main reinforcing bars of the column and the concrete or mortar are Increased unity,
Further, since the sheath directly restrains the column main reinforcing bars, buckling of the column main reinforcing bars is prevented, and structural reliability is increased.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional plan view showing the implementation status of one embodiment of the method for constructing precast reinforced concrete columns according to the present invention.
2 is a view from the arrow in FIG. 2. FIG. 2 is a front view showing the state of implementation of one embodiment of the method of the present invention, and FIG. 3 is a cross-sectional plan view showing the state of implementation of another embodiment of the method of the present invention. (8...pc pillar, (B)...floor, (1)...
・Concrete column body, (3)...sheath, (5)・
・・Column main reinforcement, (6)・・・Concrete agent
Patent attorney: Shige Okamoto (2 persons)

Claims (1)

[Claims] In the section of the column cross section where the main column reinforcing bars are placed, a PC column is embedded with a sheath that can bundle and envelop multiple main column reinforcing bars running through the column. A method for constructing a precast reinforced concrete column, the method comprising: lowering the sheath from the top of the column, fitting the sheath to the column's main reinforcing bars, and then filling the gap between the sheath and the column's main reinforcing bars with concrete or grout.