JP2003064690A - Work method for spraying short fibers for reinforcement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method enabling the easy mixing of reinforcing fibers into a cement or earth matrix to strengthen it without causing their uneven distributions there, and the continuous supply of a constant volume of such reinforcing fibers for mixing, and also provide a reinforced earth spray work method using such fiber mixed matrix. SOLUTION: A constant-volume reinforcing fiber supply method and a short- fiber mixed reinforced earth spray work method characterized by using the slivers of short fibers temporarily twisted and wounded into a cheese form, and having less than 100 dtex of average filament denier, 50-200 mm of average fiber length and 10,000 - two million dtex of total denier.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for quantitatively and continuously supplying fibers for reinforcing a matrix such as cement or soil, and a spray reinforcing method using the fiber mixed matrix.

[0002]

2. Description of the Related Art As one of the methods for forming embankments and other earth structures as stable structures, a method of mixing short fibers into a matrix to reinforce them has been carried out. That is, when the short fibers arranged between the matrices are appropriately entangled with each other, the binding force between the matrices is increased and an excellent reinforcing effect is exhibited. However, it takes a lot of time to uniformly mix a large amount of matrix and short fibers in the mixer, and the matrix mixed with short fibers is discharged from the mixer, and this is discharged through a heavy machine such as a backhoe at a construction site. It took a lot of time to carry it to the earth, and it was not possible to construct the earth structure efficiently. Moreover, even if the fibers and the matrix are simply put in a mixer and mixed, due to the extreme difference in specific gravity between the fibers, the fibers gather at the upper part of the matrix to form a so-called fiber ball (lump of fibers) or a uniform fiber. There was a problem that a mixed matrix could not be created.

[0003]

[Patent Document 1] Japanese Patent Laid-Open No. 9-78583
In Japanese Unexamined Patent Publication No. 9-78832 and Japanese Unexamined Patent Publication No. 9-78832, a non-twisted sliver having short fibers aligned is quantitatively applied to a spray nozzle according to the rotation speed of a roller while nipping or draft separating by a pair of upper and lower rollers. Methods such as feeding and mixing there with a matrix have been proposed. However, according to such a method, fiber dispersibility,
Although the processability is improved to some extent, the sliver strength is low and the sliver often breaks when it is supplied to the spraying machine, making it difficult to supply a fixed amount.In addition, a sliver with a low bulk density is put in a box or the like for civil engineering and construction sites. There was a problem that it took a lot of labor to carry it.

[0004]

[Means for Solving the Problems] As a result of intensive studies to solve the above problems, a predetermined amount of fibers can be continuously and easily supplied in a fixed amount by using a sliver of short fibers with false twist. We have found a method of supplying reinforcing fibers and a method of soil reinforcement by spraying a fiber-mixed matrix. That is, the present invention is a sliver supply method, characterized in that the sliver wound in a cheese shape by false twisting is quantitatively supplied to a mixer with an air nozzle,
Furthermore, the present invention has a single fiber fineness of 100 dtex or less, an average fiber length of 50 to 200 mm, and a total fineness of 10,000 to 2 million dte.
The present invention relates to a reinforcing method in which a sliver composed of x and supplied in a fixed amount by the above method is mixed with a matrix, and the fiber mixed matrix is discharged from a spray nozzle and sprayed.

The sliver referred to in the present invention is a bundle formed by aligning short fibers substantially in parallel, and is a drafting machine used for parlock spinning (the fibers are cut by drafting a tow with a roller. ) Or a card used for spinning, it is possible to create a sliver having a uniform thickness. In this case, scraps or recycled fibers after being used for cloth, carpet, etc. can also be used as a sliver. Alternatively, a sliver can be manufactured by drafting a bundle (tow) of continuous fibers between two or more pairs of roll grips having different rotation speeds or rotation directions to cut the fibers (parlock method). According to such a method, the sliver can be manufactured with a simple apparatus, and thus it is more preferably adopted.

Further, in order to handle the sliver and facilitate the constant supply of the sliver, a fiber spraying system as shown in FIG. 1 is used. First, the obtained sliver is false twisted to make sliver cheese 1, and from here 2
While the twist of the sliver is untwisted by the untwisting machine 3 at the entrance of the air nozzle, the compressed air of 4 passes quantitatively through the 5 air nozzles of the sliver, and is continuously fed to the mixer 9. It is fed by air and mixed with the matrix in the mixer. By discharging the matrix in which the fibers are mixed from the spray nozzle 6, the sliver can be easily handled and the sliver can be supplied in a fixed amount. As a method of applying false twist to a sliver, for example, using a device generally called Gilreducer,
Examples include a method of false twisting by drafting a sliver between two or more rollers having different rotation speeds. The false twist number of the sliver used in the present invention is 5
It is 100 t / m, and when it is less than 5 t / m, the sliver is broken and it is difficult to supply a fixed amount, and when it is more than 100 t / m, untwisting becomes difficult. More preferably 10 to 80 t /
m.

The fineness and the average fiber length of the fibers supplied as the sliver of the present invention vary depending on the machine for forming the sliver, but those having a fineness of 100 dtex or less and an average fiber length of about 50 to 200 mm can be used. When the fineness exceeds 100 dtex or the fiber length is longer than 200 mm, the dispersibility of the fibers in the soil and the reinforcing property are deteriorated, and the sliver becomes difficult to handle. On the other hand, if the fiber length is shorter than 50 mm, fiber balls are likely to be formed, which may deteriorate the dispersibility. The fineness is preferably in the range of 5 to 20 dtex and the fiber length is in the range of 70 to 150 mm.

As the fibers constituting the sliver of the present invention, any fibers such as natural fibers and organic synthetic fibers can be used. Examples thereof include polyvinyl alcohol fiber, acrylic fiber, polyester fiber, polyarylate fiber, polyamide fiber, and aramid fiber. From the viewpoint of reinforcement, it is preferable to use polyvinyl alcohol fiber. Furthermore, the total fineness of the sliver is 10,000 to 2,000,000 dt.
It must be ex. Total fineness of sliver is 10,000 dt
If it is smaller than ex, the sliver breaks and it becomes difficult to supply a fixed amount. On the other hand, if the total fineness of the sliver exceeds 2 million dtex, the dispersibility of the fiber deteriorates. It is preferably in the range of 30,000 to 1,000,000 dtex.

The matrix referred to in the present invention includes not only cement but also earth and sand used for embankments and other earth structures. The spray reinforcement construction method of the present invention can be used for all purposes such as embankment, structures, slope stabilizers, and the like. Hereinafter, the present invention will be described in detail, but the present invention is not limited to the embodiments.

[0010]

[Example] [Example 1] (1) Average single fiber fineness of 2.2 dtex, total fineness of 5300
0 dtex polyvinyl alcohol fiber tow
With a checker in Kuk spinning (manufactured by Kuraray Co., Ltd.)
Fiber 2.2 dtex, average fiber length 111 mm single fiber
Sliver with a total fineness of 42000 dtex
It was This sliver has Gilreducer (HL-5 type, large
20 t / m of false twist is applied by Saka Kiko Co., Ltd.
I chose Iber Cheese 1. (2) The spray matrix is the park compost (Olga Soi
No. 1) 67.5% by weight, beet moss (Canadian) 1
8.1 wt%, plant seed 0.1 wt% and chemical fertilizer
(Kyowa Oil Birdie) 0.8% by weight, ordinary Portland
Mix 13.5% by weight of cement with a van mixer 7,
Created. First, the matrix-mixed material
-7, knead for about 2 minutes, then belt conveyor
It was charged into the mixer 9 at 8. (3) At the same time, the sliver cheese 1 was rolled up.
The sliver 11 is separated by the sliver drawing roll 2,
Sliver 11 with untwisting machine 3 at the entrance of air nozzle 5
While untwisting the fiber, at a fiber feed rate of 100 g / min,
Supply 1% by weight of fiber to the air nozzle 5
It The fibers supplied to the air nozzle 5 are compressed air pressure 3.
5 kg / cm^TwoWhile passing through the air nozzle 5 with the pressure of
The matrix and the fibers are mixed by air feeding into the mixer 9,
Matrix from the nozzle 6 spraying fiber mixture matrix
Spray amount 6m^Three/ Hr. Air pressure at 4kg / c
m ^TwoSpraying was performed on the slope with compressed air 13. (4) The spraying operation can be continuously operated for 8 hours.
It was The dispersibility of the fibers was determined by visual observation.
As a result, fibers and fibers are uniformly dispersed, and fiber balls are not seen.
The mixture with the matrix was uniform.

[Comparative Example 1] (1) Average single fiber fineness of 2.2 dtex, total fineness of 5
A tow of 3000 dtex polyvinyl alcohol fiber was sliver with a thickness of 42000 dtex composed of monofilament 2.2 dtex and monofilament having an average fiber length of 111 mm by a drafting machine (made by Kuraray Co., Ltd.) in Parlock spinning, and false twisting was performed. It was stored in a sliver storage can without hanging. (2) The spraying matrix is 67.5% by weight of Park compost (Olga Soil No. 1), beet moss (Canadian) 1
8.1% by weight, 0.1% by weight of plant seeds, 0.8% by weight of chemical fertilizer (birdie made by Kyowa Oil), and 13.5% by weight of ordinary Portland cement were mixed in a bun mixer 7.
Created. First, the matrix-blended material was charged into the van mixer 7, kneaded for about 2 minutes, and then charged into the mixer 9 by the belt conveyor 8. (3) At the same time, a fiber supply amount of 100 g / min, and a fiber amount of 1% by weight with respect to the matrix, using the air nozzle 5,
Compressed air pressure is 3.5 kg / cm ² and is fed into the mixer 9 by air to mix the matrix and the fibers, and the spraying amount of the matrix is 6 m ³ / hr. Was sprayed on the slope with compressed air 13 with air pressure of 4 kg / cm ² at a speed of, but not only a great amount of labor was required to transport the sliver storage can, but also the sliver was cut off and quantitative supply became difficult. In many cases, spraying became difficult in 2 hours.

[0012]

According to the present invention, by using a sliver of short fibers which is false twisted, it becomes easy to quantitatively and continuously supply the short fibers, and the short fibers are dispersed more than ever before. Since it becomes uniform, the reinforcing effect of earth and sand can be further improved. Furthermore, it becomes possible to supply a fixed amount of fibers on site with a very simple device, and it becomes easy to carry out the spraying work outdoors on tunnels, slopes, etc.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a fiber spraying system used in the present invention.

[Explanation of symbols]

1: Sliver cheese 2: Sliver drawer roll 3: Untwisting machine 4: Compressed air 5: Air nozzle 6: Spray nozzle 7: Van mixer 8: Belt conveyor 9: Mixer 10: Main hose 11: Sliver 12: Plastic hose 13: Compressed air 14: Cement, soil, etc.

Claims (2)

[Claims] 1. A sliver supply, characterized in that the sliver wound into a cheese shape by false twisting is supplied to a mixer through an air nozzle while being divided by one or more pairs of upper and lower rollers. Method. 2. A single fiber fineness of 100 dtex or less, an average fiber length of 50 to 200 mm, and a total fineness of 10,000 to 2,000,000 dtex.
A reinforcing construction method comprising the steps of: mixing a sliver, which is constituted by 1. and is quantitatively supplied by the method according to claim 1, with a matrix, and discharging the fiber-mixed matrix from a spray nozzle;