JP3249017B2 - Concrete crack prevention method using sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention uses the sheet over preparative, on Concrete Cracking method using the sheet over bets so that the pouring surface of the concrete does not cause cracking.

[0002]

2. Description of the Related Art As is well known, ready-mixed concrete having sufficient fluidity is naturally dried in a state of being left naturally and solidified at a predetermined time. It evaporates with the passage of time and solidifies firmly while drying and shrinking. However, if the ready-mixed concrete is left in an environment where it is poured on a horizontal surface and dried rapidly, or if the ready-mixed concrete is improperly kneaded and there is a difference in the moisture density inside the poured ready-mixed concrete, If the moisture concentration of the concrete is not appropriate, there is a problem that cracks occur on the surface of the solidified concrete. Such a phenomenon tends to be particularly noticeable in summer when the temperature is high. For example, as shown in FIG. 5, when constructing a structure such as a building, various foundations 2 such as a cloth foundation are placed on the ground 1.
After the installation of the concrete, the fresh concrete 3 is poured into the enclosure of the foundation 2 for the purpose of improving the stability of the floor structure, moisture-proofing under the floor, improving the safety of the building construction pirate, improving the beautification, etc. After the building, the skeleton work and the finishing work are sequentially performed, and cracks 7 are also generated in the slab concrete for the reason described above.

Conventionally, in order to prevent cracks 7 from occurring on the surface of the solidified concrete, conventionally, a tension material such as a reinforcing bar or a wire mesh is included inside the ready-mixed concrete 3 to suppress drying shrinkage of the ready-mixed concrete. The surface of the ready-mixed concrete 3 may be covered with a sheet or a non-woven sheet, or water may be applied to the surface of the ready-mixed concrete 3 to reduce the evaporation rate of the water contained in the ready-mixed concrete. I have.

[0004]

However, according to the above-mentioned prior art, not only is there a problem that the cracks 7 cannot be completely prevented although the respective devices are devised, and the reinforcing steel is provided inside the ready-mixed concrete 3. When a tensile material such as wire or wire mesh is used, there is a problem that the cost increases.

[0005] When the surface of the ready-mixed concrete 3 is covered with a sheet or a non-woven sheet, it must be removed when the ready-mixed concrete 3 is solidified. There is a problem that traces and colors of the slim and stitchless sheets remain on the solidified concrete surface. In addition, there is also a problem that since the sheet without the stiffness or the stitch does not adhere to the surface of the ready-mixed concrete 3, it is turned up by an external force such as wind force and cannot be used for the purpose.

Further, when water is applied on the surface of the ready-mixed concrete 3, there is a problem that water cannot be supplied at a site where no water is supplied since water needs to be supplied.

[0007] The present invention solves the above-mentioned problems, and an object of the invention is to reduce the evaporation rate of water contained in ready-mixed concrete and reduce the amount of evaporation.
And, by using a suppressing sheet over preparative drying shrinkage of fresh concrete, is to provide a concrete crack prevention method using the nonwoven fabric sheet can be prevented from cracking that occurs when the fresh concrete is solidified.

[0008]

Means for Solving the Problems To solve the above-mentioned problems, a means for solving the above-mentioned problems is that a plurality of thin resin layers made of synthetic resin or the like are formed on the surface of the poured ready- mixed concrete .
Knit the long and short bands at right angles into a coarse mesh
The specified contact surface between the long and short strips is integrated by fusing or bonding.
To overmolded linked the sheet to the surface of the fresh concrete, by pressing by a pressing machine thereon, does not appear to have the sheet to the surface of fresh concrete sinks inside slightly from the surface of at least fresh concrete stand out In this state, the ready-mixed concrete is solidified under the condition.

[0009]

In the above method, first, a plurality of thin long strips and short strips made of synthetic resin or the like are formed on the surface of ready-mixed concrete.
Knit it into an open mesh at right angles, intersecting long and short bands
Surface of a predetermined contact surface fused or adhesion or the like so as to laid by adhering sheet <br/> over preparative linked integrally with, but here, the <br/> sheet of fresh concrete and deposited were laid in the above, overmolded said sheet to the surface of the fresh concrete,
By pressing with a pressing machine earthen swatter like thereon, or both of the surface sinks the sheet at least on the surface of fresh concrete is its thickness component is flush with, and more preferably, the sheet raw sinks inside slightly from the surface of the concrete, it refers to a state that does not appear out came floating on the surface of the raw concrete. In such state, gradually evaporates with the lapse of time since the void of the mesh of the sheet in an amount less than water normal evaporation contained in the fresh concrete. Along with that, ready-mixed concrete will dry and shrink at a slower rate than usual,
Contraction of the fresh concrete will be suppressed by attachment of the sheet.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the drawings.

[0011] Concrete Cracking method using the sheet over bets according to the present invention, for example, as shown in FIG. 1, when describing a concrete to pouring onto a horizontal plane as earthen concrete, the ground 1 according to the usual construction process After arranging the foundation 2 such as a cloth foundation, the ready-mixed concrete 3 is poured into the enclosure of the foundation 2 so as to have a predetermined thickness, and the surface of the ready-mixed concrete 3 is finished to some extent flat. in a way to lay the sheet over preparative 4 having a predetermined width W which is detailed in FIG. 2 over the surface of the fresh concrete 3.

[0012] sheet over preparative 4 above, synthetic resin or the like formed in the thin plurality of are perpendicular to the long band 4a and Tan'obi 4b knitted coarse net of eyes, long band 4a and Tan'obi 4b crossing A predetermined contact surface is integrally connected by fusing, bonding, or the like. The sheet over DOO 4 is quick and easy to perform the laying work when made to have a predetermined width W, as easy to handle keep the take-up roll form cylinder core 5 of cardboard or the like. Note that over DOO is not particularly limited to the illustrated shape as long as it has a tensile force, also the material there is no intention to be limited to the synthetic resin.

[0013] shows a specific example of laying the sheet over door 4 on the surface of the base 2 of the enclosure was poured into the ready-mixed concrete 3, the corner of one end of the enclosure of the foundation 2, that is, ready-mixed concrete 3 one edge of the digit flights or as to Komu laid first column of the sheet over preparative 4 along the Harima. At this time, the operation can be performed simply and quickly by using a pressing machine such as the soil bamboo 6 shown in FIG. The dip beat 6 includes a pair of support portions 6b having a curved grip portion 6a.
Each end which was fitted with a pressing portion 6d having a fin 6c, the wound roll of sheet over bets 4 mentioned above of,
Its sheet over bets 4 is attached in a state located at the lower side of the support portion 6b so as to be freely drawer. As the use, for example, so as to press the drawer was over <br/> surface of bets 4 by the pressing portion 6d of the earthen swatter 6 while pulling the sheet over preparative 4 by the operator A. In this case, it is necessary to deposit in a state where the surface of the fresh concrete 3 was pressed against the sheet over bets 4.

As shown in an enlarged cross section in FIG. 4, the state of the adhesion is as follows with respect to the height position of the surface of the ready-mixed concrete 3.
Sheet over the height position of the upper surface of the long band 4a and Tan'obi 4b bets 4 or at least as a flush state, more preferably, slightly inside near the height position is lower surface of the fresh concrete 3 of the upper surface subduction, shea over door 4 whole its raw concrete 3
Optimally, it does not appear from the surface. This is done by raising lead to components of the fresh concrete 3 from the mesh of the air gap 4c of sheets over preparative 4 is pressed against the strengthened slightly shea over bets 4.

[0015] After this manner laying of the first row of the sheet over bets 4 is completed, cutting the predetermined portion with a cutting means such as a cutter knife. Then, applying the laying work in a state of parallel second row of sheet over preparative 4 and the first row of the sheet over preparative 4 thereof, with respect to sheet over preparative 4 of the second row, below, Third
Th column sheet over preparative 4, the fourth column of the sheet over preparative 4, other laying subsequent sheet over preparative 4 sequentially, laying the sheet over preparative 4 by a plurality of parallel state over the surface of fresh concrete 3 To do it.
And then it is sufficient to solidify air-dried as it laid state without detaching the sheet over preparative 4 from the raw concrete 3. The corners of the ready-mixed concrete 3 can be more easily formed by pressing with a small tool such as a trowel. Further, when laying the sheet over preparative 4 on the surface of fresh concrete 3 is ultimately only to be laid shea over preparative 4 over the surface of fresh concrete 3, the laying means and laying sequence or the like to It is not limited.

[0016] By covering covers the sheet over bets 4 this manner over the surface of fresh concrete 3, moisture contained in the fresh concrete during 3 of the sheet over preparative 4 mesh void 4c
Therefore, it is possible to reduce the evaporation rate of water, and it is possible to suppress rapid evaporation and evaporation amount. Then, over <br/> preparative 4 generation of cracks becomes tensile modulus material is suppressed with respect to the drying shrinkage of the fresh concrete 3.

Thereafter, the solidified concrete is subjected to a normal surface finish, and a skeleton work for mounting various building materials such as a floor bundle and a subsequent finishing work may be performed according to a normal construction method.

Although the method for preventing cracking of concrete cast on a horizontal plane has been described above, the present invention can also be applied to a balcony floor, and furthermore, it is possible to apply a slight gradient to a movie theater or a theater. The present invention can be applied to a case where solidified concrete poured on an inclined surface is solidified, as in the case of sloping floor concrete.

[0019]

In [Effect of the Invention] Concrete Cracking method using the sheet over bets according to the present invention, the amount of evaporation it becomes possible to slow down the evaporation rate of the water contained in the fresh concrete during a cheap and simple light work Thus, the shrinkage of the ready-mixed concrete can be suppressed and the concrete can be prevented from cracking.

[Brief description of the drawings]

FIG. 1 is a partially omitted perspective view showing an embodiment of the present invention.

Figure 2 is a perspective view showing an example of a sheet over bets used in an embodiment of the present invention.

[3] the earth floor bashing a perspective view partially omitted showing a kneeling how sheet over preparative using.

FIG. 4 is an enlarged view of a part of the cross section taken along line XX of FIG. 1;

FIG. 5 is a partially omitted perspective view showing when cracks occur on the surface of soil concrete.

[Explanation of symbols]

3 raw concrete 4 over door

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Ryuji Okugawa 1-1-88 Oyodonaka, Kita-ku, Osaka Sekisui House Co., Ltd. (56) References JP-A-60-5263 (JP, A) 50-86824 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E04G 21/02 E04F 15/12

Claims (1)

(57) [Claims] 1. A plurality of thin long strips and short strips made of synthetic resin or the like on a surface of a poured ready- mixed concrete.
Are crossed at right angles to form a coarse mesh, intersecting long and short bands
The surface of the ready-mixed concrete, which is integrally connected by fusing or bonding the predetermined contact surface with it, is covered over the surface of the ready-mixed concrete, and pressed by a pressing machine from above, so that at least the surface of the ready-mixed concrete is slightly sunk inside is laid in a state where the sheet on the surface of the fresh concrete does not appear to stand out, concrete cracking prevention method using the sheet over you want to so as to solidify the raw concrete under that state.