JP2000027439A - Method for stopping placement of high-fluidity concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the efficiency of constructing high-fluidity concrete at a vertical jointing part by inhibiting the leakage of the high-fluidity concrete at a vertical placing joint part. SOLUTION: High-fluidity concrete is poured into a column part 1 separated by a vertical jointing part 11-11. Since the mesh of a retaining form 10 is closed by steel plates 12, 12 and an air fence 15, high-fluidity concrete and mortar do not leak. The air fence 15 is located between the steel plate 12 and a stirrup 6 to serve as a spacer restraining the movement of the steel plate 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for stopping high-flowable concrete at high-flowable concrete and ordinary concrete, or at a vertical joint or a vertical extension of high-flowable concrete.

[0002]

2. Description of the Related Art In the concrete construction of a concrete structure, a joint or an additional portion is usually formed on a horizontal surface and a vertical surface. Although the processing of the horizontal splicing part (stretching part) is relatively easy, the processing of the vertical splicing part (stretching part) often requires a great deal of labor, and the splicing part where proper processing is not performed Like the crack, the (struck portion) is likely to be a defective portion in terms of structure, water leakage, aesthetics, and the like.

[0003] Conventionally, in a vertically added portion of ordinary concrete, a flexible tube called an air fence is used, and this is installed vertically in a formwork provided with reinforcements.
A method of stopping concrete by filling the tube with air to expand and expand the air fence and cutting off the section of the struck portion is adopted.

[0004] When the above-mentioned air fence is used, when the rebar is thick or when the rebar is complicated,
A gap is likely to be created partially in the section of the striking part,
In the case of ordinary concrete, even if there are some gaps, the gaps formed are immediately closed by the engagement of the coarse aggregate, so that there is no problem of concrete leakage. However, in high-fluidity concrete, the composition is such that coarse aggregates do not mesh with each other, so that even a small gap leaks a considerable amount of concrete and cannot stop the concrete.

[0005] As another method, a method using a stop form having a mesh such as a lath has been practiced. In this case, in the case of ordinary concrete, the amount of mortar leaking from the mesh of the lath form is small only during the vibration compaction. However, in the case of high-fluidity concrete, the concrete leaks over a long period of time, leaving a gap between the coarse aggregates, and the original purpose of stopping the concrete cannot be achieved.

[0006] Further, as for the vertical joint, similarly to the above-mentioned vertical joint, if the concrete is ordinary concrete, the concrete can be stopped by using the stop form such as the air fence or lath. However, in high-fluidity concrete, as described above, concrete or mortar leaks violently, and such a simple stop form cannot be used.Therefore, it is necessary to form a plywood or steel form, Construction efficiency decreases.

[0007]

In recent years, high-performance high-fluidity concrete has been used for concrete structures. However, as described above, high-flowability concrete is not used for vertical joints or vertical reinforcements. In fact, there was no effective stopping method. Accordingly, an object of the present invention is to provide a tapping method capable of suppressing leakage of high-fluidity concrete in a vertically added portion.
Another object of the present invention is to provide a driving method that can increase the construction efficiency of high-fluidity concrete in a vertical joint.

[0008]

SUMMARY OF THE INVENTION According to the present invention, when joining or adding high-flowable concrete on a vertical surface, a stop form having a mesh is fixed to the joint or added portion, and a back surface thereof is fixed. It is characterized by applying high-fluidity concrete after hitting a steel plate avoiding the beam main bar. It is preferable that an air fence composed of a plurality of air tubes is installed on a back surface of the steel plate, and the air tubes are filled with air before the high-fluidity concrete is cast. Further, it is preferable that the mesh of the stop formwork is entirely closed by the steel plate.

[0009]

[Function] As described above, with the stop formwork and steel plate,
After partitioning the fill or joint, high-flow concrete is driven. Since the mesh of the stop formwork is closed by a steel plate and an air fence installed as required,
High fluidity concrete and mortar do not leak.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. In the present invention, “high-fluidity concrete” refers to concrete that is superior in flowability and filling property to ordinary concrete and can be poured in without compaction by vibration.

[0011] In the present invention, "adding" means that concrete is poured (pushed) into fresh concrete, and no seam is formed at the boundary of concrete. On the other hand, in the present invention, "joining" means that concrete is newly poured into the concrete end face after the concrete has hardened.

First, a description will be given of an embodiment relating to a method of driving high-fluidity concrete at a vertical reinforcing portion. FIG. 1 is a plan view of the column 1 and the beam 2 in the vicinity of a vertically added portion II-II before the high-flowable concrete is poured. In the present embodiment, the high-flowable concrete is poured into the column 1. Then, high-fluidity concrete having a strength different from that of the column 1 is cast into the beam 2. FIG.
(A) is a side view of the vertical addition part II-II seen from the beam part 2 side.

As shown in FIG. 1, a column main bar 4 is provided with a column main reinforcing bar 4 inside a formwork 3, and a beam main bar 5 and a stirrup 6 are provided with a beam unit 2. Prior to the placement of high-fluidity concrete, the stop formwork 10 having a mesh is fixed to the vertically added portion II-II. Such a stop form 1
As 0, a simple stop form such as a lath, expanded metal, or punched metal can be used.

Next, a steel plate 12 is applied to the outside of the stop mold 10, that is, to the beam 2 side. In this embodiment, as shown in FIG. 2A, a plurality of elongated steel plates (or iron plates) 12, 12 are inserted in the vertical direction while avoiding the beam main reinforcement 5. As shown in the modified example of FIG. 2B, the steel plates 12, 12 can be obliquely intersected to cover most of the mesh of the stop form 10, thereby stopping high-flow concrete well. be able to.

Outside the steel plates 12 (on the side of the beam 2),
Air fence 1 consisting of a plurality of air tubes 14
5 is installed. The air tubes 14, 14 are made of a material that is lightweight, flexible, and hard to adhere to concrete,
By supplying air into the air tubes 14, 14 with a mini-compressor (not shown),
4, 14 can be expanded and expanded. For this reason, it is possible to reliably close the mesh of the stop formwork 10 that could not be completely closed with the steel plates 12 and 12 alone.

However, as shown in FIG.
If the high fluidity concrete can be stopped by wrapping the steel plates 12 and 12 at an angle, it is not necessary to carefully install the air fence 15.

After partitioning the vertically added portion II-II as described above, high-fluid concrete is poured into the column portion 1. Since the mesh of the stop formwork 10 is closed by the steel plates 12, 12 and the air fence 15 installed as necessary, high-fluid concrete and mortar do not leak. Also,
The air fence 15 is located between the steel plate 12 and the stirrup 6 and serves as a spacer for suppressing the movement of the steel plate 12.

In order to add high-flowable concrete (or ordinary concrete) to the beam portion 2 after the high-flowable concrete has been poured into the column portion 1, concrete is poured into the beam portion 2 following the above operation. Immediately after casting, air tube 14
, And pull out the air fence 15. At this time, concrete is supplied while compacting as necessary so that the concrete of the beam portion 2 is filled in the portion where the air fence 15 is housed. After removing all the air fences 15, the steel plates 12 are sequentially pulled out while performing vibration compaction so that the concrete of the pillar portion 1 and the concrete of the beam portion 2 are integrated, and the operation is completed.

Next, a description will be given of an embodiment of a method for driving high-fluidity concrete at a vertical joint. FIG. 3 is a plan view near the vertical joint IV-IV of the column part 1 and the beam part 2 before the high-fluidity concrete is poured, and FIG. 4 is a vertical joint part viewed from the beam part 2 side. It is a side view of IV-IV. In the present embodiment, it is necessary to reliably stop the high-fluidity concrete poured into the column portion 1 at the vertical joint portion IV-IV.
In addition to the long steel plate 12 used in II, the steel plate 13 having a shape in which a part of the beam main bar 5 passes through is partially cut out and inserted in parallel from both left and right sides of the beam main bar 5 to form a stop formwork. All ten meshes are closed.

In the joint portion IV-IV, similarly to the contact portion II-II, the steel plate 12 (and / or the steel plate 1) is used.
Means for fixing the steel plate 12 (13) by receiving the lateral pressure of the cast concrete applied to 3) is required. The fixing means 16 may be the air tube 14, or any other fixing mechanism that can be inserted and removed between the steel plate 12 (13) and the stirrup 6. .

In this embodiment, high-fluidity concrete is poured into the column portion 1 and hardened as it is. The retaining form 10 is left embedded in the concrete, and the steel plates 12, 13
And the fixing means 16 are removed. When the fixing means 16 is constituted by the air tube 14, similarly to the embodiment of the striking portion II-II, the air can be easily pulled out by bleeding the air from the air tube 14, and at the same time, the steel plates 12, 13 are also removed. Can be easily pulled up.

[0022]

According to the first aspect of the present invention, it is possible to reliably suppress the leakage of the high-fluidity concrete at the vertically added portion. In the vertical joint,
Since a simple stop form can be used, the construction efficiency in the concrete joining operation can be improved.

According to the second and third aspects of the present invention, an excellent effect that leakage of high-fluidity concrete can be more reliably stopped can be exhibited.

[Brief description of the drawings]

FIG. 1 is a plan view of the vicinity of a vertically added portion II-II of a column portion and a beam portion.

FIG. 2 is a side view of a vertical striking portion viewed from a beam portion side.

FIG. 3 is a plan view of the vicinity of a vertical joint IV-IV between a column portion and a beam portion.

FIG. 4 is a side view of a vertical splicing portion viewed from a beam portion side.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Column part 2 Beam part 5 Beam main bar 6 Stirrup 10 Stop form 12, 13 Steel plate (iron plate) 14 Air tube 15 Air fence 16 Fixing means II-II Vertical extension part IV-IV Vertical joint part

Continued on the front page (72) Inventor Makoto Hamada 1043 Onigakubo, Tsukuba, Ibaraki Pref. Inside Kumagaya Gumi Technical Research Institute (72) Inventor Kenji Yoshimatsu 2-1, Tsukudo-cho, Shinjuku-ku, Tokyo In-house (72) Inventor Koichi Sato 2-1 Tsukudo-cho, Shinjuku-ku, Tokyo F-term (reference) 2E172 AA09 DD01 DE00

Claims (3)

[Claims] When joining or adding high-fluidity concrete on a vertical surface, a fastening form having a mesh is fixed to the joint or the added portion, and a steel plate is attached to the back surface of the concrete body while avoiding the main beam reinforcement. A method of driving high-fluid concrete, characterized by driving high-flow concrete after applying. 2. The method according to claim 1, wherein an air fence comprising a plurality of air tubes is installed on the back surface of the steel plate, and the air tubes are filled with air before the high-fluidity concrete is poured. . 3. The driving method according to claim 1, wherein the mesh of the stop form is entirely closed by the steel plate.