JPH07331679A - Concrete casting to rise in basement in inverted construction method - Google Patents

Abstract

PURPOSE:To improve quality and efficiency in execution of work by a method wherein concrete in specific property is injected into forms for rises in a basement through injection pipes provided to through holes of an upstairs floor or injection pipes embedded in upstairs columns and beams. CONSTITUTION:Superplasticized concrete in slump value of 25-28cm, in slump flow value of 500-750mm and containing segregation reducing agent such as cellulose derivatives is used for casting. In execution of work, concrete 7A is injected into an injection pipe 6A that is for casting concrete for columns, and filling is made up to the underside of an existing column 1. Then concrete 7B is injected through the injection pipe 6B and filling is made up to the underside of the existing column 1. Furthermore, concrete 7C is injected through the injection pipe 6C and filling is made up to the underside of an existing beam 2. Then, additional pipes 11 are connected to the injection pipes 6A, 6B and 6C, and filling of concrete is made therethrough, and the placed concrete is pressurized to ensure the filling. Thereby, occurrence of gaps and segregation of material on horizontal construction joint of concrete can be prevented while improving efficiency in execution of work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving method for driving rising concrete on a basement floor by a reverse driving method.

[0002]

2. Description of the Related Art As a conventional method of driving upright concrete (column / wall concrete) on a basement floor by the reverse-placing method, the following method is adopted.

(A) A so-called sleeve construction method in which an existing upper floor is used as a working floor.

(A-1) A method in which a through hole is provided in an existing beam on the floor above the rising concrete driving portion, and concrete is driven through the through hole. (See Fig. 5 (a)) (A-2) A through hole is provided in the upper floor of the place slightly displaced from the rising concrete driving portion, and concrete is poured into the upper side surface of the rising concrete formwork on the basement floor through the through hole. A method of mounting pipes and driving concrete from the upper floor through concrete injection pipes. (See Fig. 5 (b)) (B) Construction method using the basement floor as a working floor.

(B-1) A construction method in which a morning glory is attached to the upper end of the formwork of the rising concrete driving section, and concrete is driven by the work on the scaffold assembled on the basement floor. (Fig. 5 (c)
(B-2) A method of attaching a concrete press-fitting pipe to the bottom surface of the formwork and press-fitting concrete upward from the press-fitting pipe. (See FIG. 5 (d)) And, as the concrete to be poured, the slump value 21
The thing of about cm is used.

[0006]

A drawback common to the conventional construction methods is that there is a great risk that breathing will occur in the concrete to be placed and that a gap will be created on the horizontal joint surface.

Since the work on the scaffold assembled on the basement floor of (B-1) has poor workability and is dangerous, there is a large possibility that the vibrator cannot be sufficiently hung on the entire surface of the body. In addition, the concrete injection time becomes long, the filling property deteriorates due to slump loss, and the occurrence of junkers and cold joints deteriorates the quality of concrete. Then, it is necessary to completely remove the concrete placed in the morning glory mounting portion after hardening.

In the case of the so-called sleeve construction method of (A), there is no danger in work, but as in the case of (B-1), since the vibrator cannot be sufficiently applied, the quality of concrete is deteriorated. In the case of (A-1), since the through hole has a cross-section loss, the design is changed to increase the size of the column or the beam width by the amount corresponding to the size, so-called "puff" portion. It is necessary to carry out additional construction, which is not preferable in terms of planning. In the case of the concrete press-fitting method of (B-2), there is no work risk and there is almost no deterioration in the quality of the concrete, but the amount of placement is affected by the number of injection pipes attached, and large-scale formwork work is performed. , Pipe installation work is required,
Inferior in workability and economy. These problems may be due to the construction method, but also due to the concrete used.

[0009]

The present inventors previously invented a high fluidity concrete without breathing (Japanese Patent Laid-Open No. 5-279101). This high fluidity concrete is used for the upstairs concrete by the upside down construction method,
As the construction method, by adopting the sleeve construction method which is a modification of the above (A-2) or (A-1) and does not require additional construction of the "puffed" portion, the above-mentioned various problems of the reverse construction method The present invention has been reached by discovering that the above can be solved.

That is, according to the present invention, "a through-hole penetrating up and down is provided in the upper floor, and a concrete injection pipe is attached to the upper side surface of a concrete formwork standing on the basement floor of the floor through the through-hole. , In the reverse construction method of injecting concrete from the upper floor through a concrete injection pipe, use high-fluidity concrete with a slump value of 25 to 28 cm and a slump flow value of 500 to 750 mm and containing a separation reducing agent. The method of driving upright concrete on the basement floor by the upside-down construction method "and the claim 2," A concrete injection pipe that vertically or diagonally penetrates an existing column and an existing beam at the upper edge of this floor is not damaged. And then insert it from the upper floor through the concrete injection pipe into the rising concrete formwork on the basement floor on this floor. In addition to adopting the reverse construction method of injecting concrete, the slump value is 25 as concrete.
~ 28 cm, slump flow value is 500-750 mm, and high-fluidity concrete containing a separation reducing agent is used.

The point of the present invention is that the reverse construction method by the sleeve construction method is performed by using high fluidity concrete without breathing.

The compounding and manufacturing method of the high fluidity concrete without breathing used in the present invention has been described in detail in the specification of the above invention, but the outline thereof will be described.

Cement amount 300 to 450 kg / m ³ , kneading water amount 175 to 190 kg / m ³ , water cement ratio 40 to 60%,
In addition to the separation reducing agent, the concrete high performance water reducing agent, water reducing agent, AE agent, AE water reducing agent, etc., which are surfactants, are usually added in appropriate amounts to the concrete mixed with the fine aggregate ratio of 45 to 60%. By uniformly kneading with the above method, the high fluidity concrete without breathing used in the present invention can be obtained.

As the separation reducing agent, high-performance water reducing agent, water reducing agent, AE agent, AE water reducing agent, etc., ordinary commercial products are used. The separation reducing agent is a water-soluble polymer compound, and typical examples thereof include cellulose derivatives such as cellulose ester and cellulose ether, and polyacrylic acid (salt) and its derivatives.

The slump value of the high-fluidity concrete used in the present invention is a value according to the slump test of JIS A 1101, and the slump flow value is a measurement value of the diameter of the concrete that has flowed on the flat plate during the slump test. .

The fluidity of the high-fluidity concrete used in the present invention is hardly reduced even after 120 minutes have passed after kneading, and breathing does not occur. In the meantime, there is no risk that the quality of the concrete will deteriorate and that there will be gaps in the horizontal joint surface. Therefore, according to the present invention, the problems of the conventional upside-down construction method can be solved at once.

The reverse construction method adopted in the present invention according to claim 2 eliminates various irrationalities that have occurred because the adoption of the conventional (A-1) construction method is decided after the design of the frame is completed. This is a modified construction method that takes into consideration embedding a concrete injection pipe in the beam at the time of design, including the material and shape of the injection pipe, and does not cause a cross-section loss by embedding the concrete injection pipe. is there. For this reason, a steel pipe having an appropriate shear connector attached to the inner and outer surfaces is used as the concrete injection pipe to be embedded, and if necessary, reinforcing bars are arranged around the steel pipe. The concrete injection pipe is finally filled with concrete and completely embedded in the concrete.

[0018]

EXAMPLES The present invention will be described below with reference to examples.

Using the materials shown in Table 1 below, concrete was prepared with the composition shown in Table 2. The slump value of the obtained concrete is 27 cm, the slump flow value is 660 mm,
The amount of breathing (test according to JIS A 1123) was 0.00 cm ³ / cm ² .

The value at 120 minutes after mixing was 2 each.
It was 6 cm, 650 mm, and 0.00 cm ³ / cm ² .

[0021]

[Table 1]

[0022]

[Table 2]

A construction method for constructing columns and walls on the basement floor by the sleeve construction method using this high-fluidity concrete will be described with reference to the drawings.

An example of the invention described in claim 1 will be described with reference to FIGS.

FIG. 1 shows an example of a state around the upper floor before concrete placing, (a) is a plan view, (b) is a vertical sectional view around a wall concrete placing injection pipe, and (c). [Fig. 3] is a vertical cross-sectional view in a direction orthogonal to (b), and (d) is a vertical cross-sectional view around the injection pipe for pouring concrete.

FIG. 2 is a process vertical sectional view showing a process of placing concrete.

The upper floor 4 is provided with through holes 3 which penetrate vertically by embedding sleeves around the columns 1 and around the beams 2. The through hole 3 is usually provided at one place for one pillar 1, but may be omitted if the pillar interval is short. The through holes 3 around the beam 2 are provided at one or two places depending on the length of the span. In the example shown, the pillar 1,
It is provided at one place approximately in the middle of 1.

A concrete pouring pipe 6 is attached to the upper end side surface of the rising concrete formwork on the basement floor and opens near the lower end surface of the existing pillar 1 or beam 2 constructed in advance.
A funnel is installed on the through hole 3 of the upper floor 4, and the funnel and the concrete injection pipe 6 are connected by a flexible hose that passes through the through hole 3. In this specification, the concrete injection pipe 6 and the flexible hose connected thereto are collectively referred to as the concrete injection pipe 6, and the funnel is also sometimes integrally referred to as the concrete injection pipe 6.

The construction procedure will be described with reference to FIG.

(1) The high-fluidity concrete 7A is poured from the concrete transport pipe 8 into the column concrete pouring injection pipe 6A, and the pouring of basement rising concrete is started (FIG. 2 (a)). It is confirmed that the high-fluidity concrete 7A has been sufficiently filled up to the lower surface of the existing column 1 by the outflow of slag from the air vent hole 9 and the percussion of the dam plate.

(2) The concrete transport pipe 8 is replaced with the adjacent column concrete pouring injection pipe 6B and the pouring of the high-fluidity concrete 7B is started from the column concrete pouring injection pipe 6B (FIG. 2 (b)). ). Air vent hole 9 as in (1)
It is confirmed that the high-fluidity concrete 7B has been sufficiently filled up to the lower surface of the existing column 1 by the outflow of slag and the percussion of the dam plate. During the work of (2), when the high-fluidity concrete 7A injected earlier flows and an unfilled portion is generated between the high-fluidity concrete 7A and the lower surface of the existing pillar 1, the work of (1) is performed again. To do.

(3) High flowability concrete 7A and 7
After confirming that B has been sufficiently filled up to the lower surface of each existing pillar 1, the concrete transportation pipe 8 is replaced with a wall concrete pouring injection pipe 6C, and the flowability concrete is higher than that of the wall concrete pouring injection pipe 6C. The injection of 7C is started (FIG. 2 (c)). (1) Similar to (2), it is confirmed that the high-fluidity concrete 7A is sufficiently filled up to the lower surface of the existing beam 2 by outflow of slag from the air vent hole 9 and percussion of the dam plate. During the work of (3), the high-fluidity concrete 7A, 7B injected earlier flows and the high-fluidity concrete 7A,
If an unfilled portion occurs between 7B and the lower surface of the existing column 1, the work of (1) or (2) is performed again.

Air vent hole 1 formed in the corner of the mold
It is confirmed by 0 that the high fluidity concrete 7C has been filled up to the corner portion. By the operations of (1) to (3), the mold is filled with the highly fluid concrete 7.

(4) All of the injection pipes 6A, 6B, 6C or any one of them (in the present embodiment, 6 having a high opening position)
The additional pipe 11 is connected to the upper part of the C1 pipe, and the high-fluidity concrete 7 is filled in the additional pipe 11, and the pressure is applied to the already-placed concrete 7 by the weight of the concrete to ensure the filling. . (FIG. 2 (d)). (1)-(4)
This completes the placement of high-fluidity concrete for one span.

(5) After the concrete is hardened and the formwork is dismantled, the pouring pipe and the hardened concrete in the pouring pipe are removed by cutting or chipping.

In this way, the columns and walls of the basement for one span are constructed and moved to the next span. When the pillars / walls on the first basement floor are constructed, the pillars / walls on the second basement floor are constructed by the same operation with the first basement floor as the upper floor, and the third basement floor, the fourth basement floor ...
Proceed to.

Next, referring to FIG. 3 and FIG.
An example of the described invention will be described.

FIG. 3 shows an example of a state around the upper floors before pouring concrete, (a) is a plan view, (b) is a vertical cross-sectional view around a wall concrete pouring pipe, (c) , (D) is a vertical cross-sectional view around the injection pipe for placing concrete in a column.

FIG. 4 is a process vertical sectional view showing a process of placing concrete.

A concrete pouring pipe 12 penetrating vertically or obliquely is embedded in the pillar 1 and the beam 2 around the pillar 1. A concrete injection pipe 12 that penetrates vertically is embedded in the middle beam 2. The concrete injection pipe 12 is usually provided at one place for one pillar 1, but may be omitted if the pillar interval is short. The intermediate concrete injection pipe 12 is provided in one or two places depending on the length of the span. In the illustrated example, one location is provided approximately in the middle of the pillars 1, 1.

A funnel is installed on the concrete injection pipe 12, and a rising concrete mold assembled under the existing pillars 1 and beams 2 constructed by preceding the high-fluidity concrete through the funnel and the concrete injection pipe 12. It is injected into the frame.

Generally, since an upper floor pillar has already been constructed above the existing pillar 1, in order to inject concrete from the upper floor, the column concrete pouring injection pipe 12 is provided as shown in (c). It is necessary to bury the existing beam 2 and the existing pillar 1 so as to penetrate diagonally, but the upper floor pillar above the existing pillar 1 is not constructed as in the case of the first floor construction by the upside down construction method. In this case, it is preferable from the viewpoint of construction that the existing pillar 1 is embedded so as to vertically penetrate therethrough as shown in (d). Also,
The end of the injection pipe 12 for pouring concrete is the existing pillar 1.
Need not be opened immediately below, and may be embedded so as to vertically penetrate the existing beam 2 in the vicinity of the existing pillar 1.

Since the construction method according to claim 2 is slightly different from the construction method according to claim 1 in the concrete pouring place,
The construction procedure is the same as the case of FIG. 2, but FIG. 4 is taken as an example when the injection pipe 12 for pillar concrete placing is buried obliquely.
Will be described with reference to.

(1) When the upper floor 4, the beam 2 and the pillar 1 are constructed in advance, concrete injection pipes 12A, 12B, 12 are provided with steel pipes with shear connectors at predetermined positions of the beam 2 and the pillar 1.
It is buried as C. Concrete injection pipe 12A, 1
Install the funnel on top of 2B and 12C.

(2) High-fluidity concrete 7A is poured from the concrete transport pipe 8 into the injection pipe 12A for pillar concrete placement.
To start pouring concrete on the basement floor (Fig. 4 (a)). High-fluidity concrete 7A was added to the existing pillar 1 due to spillage from the air vent hole 9 and percussion on the dam plate.
Make sure that the bottom surface of is fully filled.

(3) The concrete transport pipe 8 is replaced with the adjacent column concrete pouring injection pipe 12B and the injection of the high-fluidity concrete 7B is started from the column concrete pouring injection pipe 12B (FIG. 4 (b)). ). Similarly to (1), it is confirmed that the high-fluidity concrete 7B has been sufficiently filled up to the lower surface of the existing column 1 by the outflow of slag from the air vent hole 9 and the percussion of the dam plate. During the work of (3), if the high-fluidity concrete 7A injected earlier flows and an unfilled portion occurs between the high-fluidity concrete 7A and the lower surface of the existing pillar 1, perform the work of (2) again. To do.

(4) High flowability concrete 7A and 7
After confirming that B has been sufficiently filled up to the lower surface of each existing pillar 1, the concrete transport pipe 8 is replaced with a wall concrete pouring injection pipe 12C, and the flowability concrete is higher than that of the wall concrete pouring injection pipe 12C. The injection of 7C is started (FIG. 4 (c)). (2) Air vent hole 9 as in (3)
It is confirmed that the high-fluidity concrete 7A has been sufficiently filled up to the lower surface of the existing beam 2 by the outflow of slag and the percussion of the dam plate. During the work of (4), the high-fluidity concrete 7A, 7B injected earlier flows and the high-fluidity concrete 7
When an unfilled portion occurs between A and 7B and the lower surface of the existing column 1, the work of (2) or (3) is performed again. It is confirmed that the high-fluidity concrete 7C is filled up to the entering corner by the air vent hole 10 opened in the corner of the mold.
By the operations of (2) to (4), the mold is filled with the highly fluid concrete 7.

(5) All of the injection pipes 12A, 12B, 12C or any one of them (in the present embodiment, the middle 12
The additional pipe 11 is connected to the upper part of the C1 pipe, and the high-fluidity concrete 7 is filled in the additional pipe 11, and the pressure is applied to the already-placed concrete 7 by the weight of the concrete to ensure the filling. . (FIG.4 (d)). (2)-(5)
This completes the placement of high-fluidity concrete for one span.

(6) Addition pipe 11 after hardening of concrete
And remove the funnel.

In this way, one span of basement floor rising concrete is constructed and moved to the next span.
When the rising concrete on the first basement floor is constructed,
By using the same operation as the upper floor, the rising concrete of the second basement floor is constructed by the same operation, and proceeds to the third basement floor, the fourth basement floor ...

[0051]

【The invention's effect】

(1) Since high-fluidity concrete that does not cause breathing is used, no gap is created on the horizontal casting joint surface.

(2) Since the high-fluidity concrete retains its fluidity for a long time, it is possible to improve the degree of adhesion with the already-placed concrete by the pressure of the weight of the concrete in the additional pipe.

(3) Since the high-fluidity concrete retains its fluidity for a long time and does not cause material separation, it does not cause a junker or a cold joint even if it is not compacted by a vibrator, etc. Never invite.

(4) The work can be performed with a small amount of piping, the workability is improved, and the work of removing the injection pipe and the concrete in the injection pipe after the installation is reduced.

(5) As a result of the above, it is possible to construct a high-quality building without requiring a skilled concrete operator.

[Brief description of drawings]

1 shows an example of a state around the upper floor before pouring concrete when pouring concrete from the upper side of the formwork, (a) is a plan view, (b) is a wall concrete pouring pipe FIG. 3 is a vertical cross-sectional view of the periphery, FIG. 6C is a vertical cross-sectional view in a direction orthogonal to FIG.

FIG. 2 is a process vertical cross-sectional view showing a process of placing concrete when pouring concrete from the upper end side surface of the formwork.

FIG. 3 shows an example of a state around the upper floor before pouring concrete when pouring concrete from above the formwork,
(A) is a plan view, (b) is a longitudinal cross-sectional view around the wall concrete pouring injection pipe, (c), (d) is a vertical cross-sectional view around the pillar concrete pouring injection pipe.

FIG. 4 is a process vertical sectional view showing a process of placing concrete when pouring concrete from above the formwork.

FIG. 5 is a vertical cross-sectional view showing various conventional reverse construction methods.

[Explanation of symbols]

1 ・ ・ Existing pillars 2 ・ ・ Existing beams 3 ・ ・ Upper floor penetration hole 4
..Upper floors, 5 ... Basement floors, 6, 6A, 6B, 6C
・ Concrete injection pipes, 7, 7A, 7B, 7C ・ ・ High-fluidity concrete, 8 ・ ・ Concrete transport pipes, 9 ・ ・
Air vent hole, 10 ... Air vent hole, 11 ... Additional pipe, 1
2, 12A, 12B, 12C ··· Concrete injection pipe.

Front page continuation (72) Inventor Akira Abe 1-3-8 Moto-Akasaka, Minato-ku, Tokyo Inside Kashima Construction Co., Ltd. Tokyo branch (72) Inventor Hiromasa Hara 1-3-8 Moto-Akasaka, Minato-ku, Tokyo Kashima Construction Co., Ltd.Tokyo Branch

Claims (2)

[Claims] 1. A through hole is provided in the upper floor to vertically penetrate the floor.
A concrete injection pipe is attached to the upper side of the rising concrete formwork on the basement floor of this floor through this through hole, and when the concrete is injected from the upper floor via the concrete injection pipe, the slump value of concrete is 2
A method for driving concrete upright on the basement floor by a reverse-casting method, which is characterized by using high-fluidity concrete having a slump flow value of 5-28 cm and a slump flow value of 500-750 mm and containing a separation reducing agent. 2. A concrete injection pipe that vertically or diagonally penetrates an existing column and beam on the upper edge of the floor so as not to cause a cross-sectional defect, and is passed through the concrete injection pipe from the upper floor to the basement floor of this floor. It is characterized by adopting the reverse casting method of injecting concrete into the rising concrete formwork, and using as the concrete high-fluidity concrete with a slump value of 25 to 28 cm and a slump flow value of 500 to 750 mm and containing a separation reducing agent. The method of driving concrete upright on the basement floor by the reverse method.