JP2003129493A - Concrete skeleton and continuous footing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To overcome a problem such that the beauty of a continuous footing is damaged or the durability of the continuous footing is decreased as the case may be, because zigzag cracks are caused around a ventilating hole in a radially spread manner by drying shrinkage attendant on curing of concrete, when the ventilating hole is provided in the continuous footing. SOLUTION: Crack inducing joints 23 are provided in a rising wall part 3 of the continuous footing 1 by making one end communicate with the ventilating hole 16; and the cracks, which are caused around the ventilating hole 16, are concentrated into the joints 23. Thus, the cracks are inhibited from being randomly spread, so that an appearance can be prevented from being deteriorated.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a concrete skeleton and a cloth foundation.

[0002]

2. Description of the Related Art A cloth foundation used as a foundation of a building or the like is generally formed in an L-shaped section or an inverted T-shaped section having a footing and a standing wall portion standing on the footing. It has a reinforced concrete structure (RC structure), and in many cases, reinforcing bars are embedded and reinforced in the concrete of the footing portion and the standing wall portion, respectively. In addition, this cloth foundation,
It is common to provide ventilation holes by penetrating the front and back surfaces of the standing wall portion at predetermined intervals in the longitudinal direction. The ventilation hole has a so-called hollow structure in which a rectangular opening is provided in the heightwise intermediate portion of the standing wall, or a so-called top-cut structure in which a recessed portion that opens toward the upper surface of the standing wall is opened. is there.

[0003]

In the ventilation hole of the hollow structure, there are four inner corners in the opening, but due to the dry hardening and shrinkage of concrete occurring after the construction of the cloth foundation,
In some cases, zigzag-like cracks are generated from some or all of the inner corners of these four locations in the diagonally outward direction (toward the four directions). In the ventilation hole with the upper punched structure, since the opening shape is a concave portion that opens upward, the inner corners are at the lower two places, so the cracks may be halved compared to the case of the hollowed structure. There is no substitute in terms of cracking.

When such cracks occur, carbon dioxide gas and other oxides in the air penetrate into the standing wall, which causes the alkalinity of the concrete to be lowered, and at the same time, this situation. If oxygen, water, or the like further penetrates through the cracks below, the reinforcing bars embedded in the standing wall portion may be corroded, and the durability of the cloth foundation will be reduced. Needless to say, even if the cracks are generated, the appearance of the cloth foundation becomes unsatisfactory. The present invention has been made in view of the above circumstances, in a concrete skeleton having a standing wall portion such as a cloth foundation, the appearance deteriorates due to cracks that occur around openings such as ventilation holes, and durability. It is an object of the present invention to provide a concrete skeleton and a cloth foundation that can prevent the deterioration of the water content.

[0005]

In order to achieve the above object, the present invention takes the following technical means. That is, the concrete skeleton according to the present invention has a standing wall portion and is provided with an opening penetrating the standing wall portion in the front and back direction thereof, and is at least the surface direction of the standing wall portion. One end is in communication with the opening on the wall surface, and a crack-inducing joint extending downward from the vicinity of the corner of the lower end of the opening is recessed.

By providing such crack-inducing joints, it is possible to concentrate the cracks caused by the drying shrinkage of concrete in the crack-inducing joints. That is, cracks generated on the wall surface of the standing wall often occur in any direction from the lower end corner portion of the opening, but if the above-mentioned crack generation joint is provided, the majority of such cracks will be along the joint. Since it is difficult to generate in one direction and spread to another direction, it is possible to suppress deterioration of the appearance of the standing wall portion due to the occurrence of a crack as much as possible. In the present invention, it is preferable to embed a backup material along the longitudinal direction of the crack-inducing joint and attach a waterproof tape in a state of covering the backup material. By doing so, it is possible to prevent carbon dioxide gas and other oxides in the air from penetrating into the standing wall portion from the cracks generated in the crack-inducing joints, so that it is not possible to reduce the alkalinity of concrete. I won't. Further, since oxygen, moisture, etc. do not directly permeate through the cracks, it is possible to prevent the reinforcing bars embedded in the standing wall portion from corroding.

The wall surface to which the waterproof tape is attached is further applied with a surface finishing material from above, and the surface finishing material includes a position corresponding to the outer edge on one side in the width direction of the waterproof tape. It is preferable to provide makeup joints in different positions. In this way, the crack generated at the crack-inducing joint cannot be seen from the outside. Also, even if a crack is generated on the surface finishing material side due to the crack generated at the crack-inducing joint,
Since the cracks generated in this surface finish material are along the makeup joint, this also makes them inconspicuous.

On the other hand, the cloth foundation according to the present invention has a footing and a standing wall portion standing on the footing, and has a ventilation opening penetrating the standing wall portion in the front and back direction. A crack countermeasure structure having the above-described crack-inducing joint as a main part is adopted around the ventilation opening at least on the surface side of the standing wall portion.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment of a cloth foundation 1 according to the present invention. The cloth foundation 1 of the illustrated example has a footing 2 and a standing wall portion 3 standing upright on the footing 2 and is formed in an inverted T-shaped cross section. Reinforcing bars 4 are embedded and reinforced in the footing 2 and the standing wall portion 3, respectively. As shown in FIG. 2, in the present embodiment, the floor material 8 is laid on the upper part of the cloth foundation 1 with the floor base panel 6, the joists 7 and the like interposed therebetween. Further, an outer wall panel 10 is built in via a draining material 9, and the outer wall panel 1
The reinforcing material 11, the filler 12, and the interior material 13 are attached to the back surface side of 0.

The standing wall portion 3 is provided with an opening portion 16 as a ventilation hole penetrating through the front and rear surfaces thereof. In the illustrated example, the opening 16 is open upward (so-called top-out structure). A plurality of such opening portions 16 are provided at a predetermined distance in the longitudinal direction of the standing wall portion 3. A step portion 17 (see FIG. 1) generated by widening the opening space on the outside and narrowing the opening space on the inside is provided in the opening 16 at the center in the thickness direction of the standing wall portion 3. The ventilation plate 18 is fitted in such a manner that it is applied to the outside of the portion 17.

The ventilation plate 18 may be of vertical stripe type, horizontal stripe type, lattice type, porous distribution type, half type, or the like. A surface finishing material 20 such as mortar is applied to the surface side of the standing wall portion 3 (the surface on the outside of the building). The surface finish material 20 is also applied to the opening space portion outside the step portion 17 in the opening portion 16. As shown in FIG. 1, the cloth foundation 1
The standing wall portion 3 is provided with a crack-inducing joint 23 at least on the surface side wall.

The crack-inducing joint 23 has one end communicating with the opening 16, and is formed so as to extend downward from the vicinity of the corner of the lower end of the opening 16. In the illustrated example, the opening 16 extends vertically downward from the lower edge of the opening 16. Further, the crack-inducing joints 23 are provided at positions near both ends (either one side or both sides) of the opening 16 in the longitudinal direction and on both front and back surfaces of the standing wall portion 3. Therefore, one opening 1
6, a maximum of four crack-inducing joints 23 can be provided.

Although not shown, such a crack-inducing joint 23 is provided with a joint-forming material in the form (the inner surface of the weir plate before placing concrete) when the standing wall 3 is constructed. It can be formed by placing. As shown in FIGS. 3 and 4, the backup material 25 is embedded in the crack inducing joint 23 along the longitudinal direction thereof, and as shown in FIGS. 5 and 6, the backup material 25 is covered. It is preferable to attach the waterproof tape 26 in this state. As the backup material 25,
A flexible rod-shaped member made of rubber or resin having a predetermined performance (elasticity, waterproof property, corrosion resistance, etc.) can be used. It is preferable to use, as the backup material 25, a material that can be pushed into the crack-inducing joint 23 while being slightly press-fitted to fill the inside of the crack-inducing joint 23. In addition, a putty-like material (which may become an elastic body after being applied to the crack-inducing joint 23) may be used.

As the waterproof tape 26, one made of butyl rubber or the like and having adhesiveness on one side may be used. When the waterproof tape 26 is attached, the lower surface finishing material 20 is applied and applied to at least the surface side of the standing wall portion 3. In this case, the surface finishing material 20 is applied to one side in the width direction of the waterproof tape 26. It is preferable to provide the makeup joint 27 with the positioning including the outer edge corresponding position. The makeup joint 27 may be formed of a known dry joint material or may be formed of a known wet joint material.

In the cloth foundation 1 of the present invention having the above-mentioned structure, since the crack-inducing joints 23 are provided on the standing wall portion 3, when the standing wall portion 3 (cloth foundation 1) is installed, the concrete is dried and shrinks. It is possible to concentrate the cracks generated in association with the crack-induced joint 23. That is, a crack often occurs on the surface of the standing wall portion 3 from the lower end corner portion of the opening 16, but the crack generated on the surface of the standing wall portion 3 is likely to occur in the direction along the crack-inducing joint 23, and this joint It becomes difficult to spread to the part outside 23. Also,
In this embodiment, the crack-inducing joints 2 are formed on both front and back surfaces of the standing wall portion 3.
Since the cracks 3 are arranged so as to face each other, for example, as shown in FIG. 7, the cracks 30 are more likely to occur in a state in which the crack-inducing joints 23 on the front and back sides are connected to each other inside the standing wall portion 3. 30 is not a zigzag shape but is likely to be a substantially linear shape, and the crack-inducing joint 23
Since the tensile force due to the drying shrinkage of the concrete is absorbed by the cracks 30 that are concentrated on the cracks, the occurrence of cracks other than the crack-induced joints 23 can be suppressed. For this reason, it is possible to suppress deterioration of the appearance of the standing wall portion 3 (cloth foundation 1) as much as possible.

Further, the crack 30 generated at the crack-inducing joint 23 is in a state of being stopped by the backup material 25 filling the inside of the crack-inducing joint 23 and the waterproof tape 26 covering the backup material 25. It is possible to prevent carbon dioxide gas and other oxides in the air, oxygen, water and the like from penetrating into the standing wall portion 3 into the cracks 30. Therefore, deterioration of the alkalinity of the concrete due to the cracks 30 and corrosion of the reinforcing bar 4 that occurs thereafter are suppressed. Even if a crack is generated on the surface finishing material 20 side due to the crack 30 generated at the crack-inducing joint 23, this crack appears along the makeup joint 27 provided on the surface finishing material 20. , This crack is also unnoticeable.

By the way, the present invention is not limited to the above-mentioned embodiments, but the details can be changed as appropriate. For example, the opening 16 is not limited to the ventilation hole. That is, in the present invention, the standing wall portion 3 is not limited to that of the cloth foundation 1, but covers the entire concrete skeleton including the standing wall portion as the outer wall of the building, and thus is formed in this type of standing wall portion. Of course, all the openings you get (eg windows, doorways, etc.) are also covered.

The formation direction and arrangement of crack-inducing joints 23 with respect to the opening 16, the number of formed joints, and the dimensions such as joint width and joint depth are not particularly limited.

[0019]

As described above, according to the concrete skeleton and the cloth foundation according to the present invention, since the crack-inducing joints are recessed in the wall surface of the standing wall portion, the cracks generated in the standing wall portion become the crack-inducing joints. It is possible to concentrate and prevent deterioration of appearance. In addition, if a waterproof treatment such as a backup material is attached to the crack-inducing joints and a waterproof tape is applied, it is possible to prevent the corrosion-causing substance from penetrating from the cracks and prevent corrosion of the reinforcing bar. It is possible to effectively prevent a decrease in durability of the concrete skeleton or the cloth foundation due to the concentration of cracks.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a cloth foundation according to the present invention.

FIG. 2 is a side sectional view showing an actual construction situation of the cloth foundation of FIG.

FIG. 3 is a perspective view of an essential part showing how a backup material is attached to the cloth foundation of FIG.

4 is a cross-sectional view taken along the line AA of FIG.

5 is a perspective view of relevant parts showing a state in which a waterproof tape is further attached through the operation of FIG.

6 is a cross-sectional view after attachment of the waterproof tape, which is shown corresponding to line BB in FIG.

FIG. 7 is an enlarged cross-sectional view illustrating the state of occurrence of cracks corresponding to the line CC of FIG.

FIG. 8 is a perspective view showing only the cloth foundation extracted from FIG.

[Explanation of symbols]

1 cloth foundation 2 footing 3 standing wall 16 openings 20 Surface finish 23 Crack-induced joints 25 backup material 26 waterproof tape 27 Makeup Joint

Continued front page    (72) Inventor Motoki Tanaka             3-12-12 Minamisenba, Chuo-ku, Osaka-shi, Osaka Prefecture               Kubota House Co., Ltd. (72) Inventor Shuichi Inoue             3-12-12 Minamisenba, Chuo-ku, Osaka-shi, Osaka Prefecture               Kubota House Co., Ltd. F-term (reference) 2D046 BA00                 2E001 DB02 DH34 EA02 FA21 FA51                       NA03 NB01 ND01

Claims (4)

[Claims] 1. A standing wall portion (3) and said standing wall portion (3).
In the concrete skeleton provided with an opening (16) penetrating in the front and rear direction with respect to the vertical wall (3)
A crack-inducing joint (23) having one end communicating with the opening (16) and extending downward from the vicinity of the corner of the lower end of the opening (16) is recessed on the wall surface of the. A concrete skeleton characterized by that. 2. A backup material (25) is embedded in the crack-inducing joint (23) along the longitudinal direction thereof, and a waterproof tape (26) is attached so as to cover the backup material (25). The concrete skeleton according to claim 1, which is attached. 3. The wall surface to which the waterproof tape (26) is attached is further applied by a surface finishing material (20) from above, and the waterproof tape (26) is applied to the surface finishing material (20). 3. The concrete frame according to claim 2, wherein the makeup joint (27) is provided so as to include a position corresponding to the outer edge on one side in the width direction. 4. A footing (2) and the footing (2)
A standing wall portion (3) standing upright and provided with a ventilation opening (16) penetrating the standing wall portion (3) in the front and back direction thereof. Around the ventilation opening (16) on the wall surface of (3),
The crack-inducing joint (2) according to any one of claims 1 to 3.
A cloth foundation characterized in that a crack countermeasure structure including 3) is adopted.