JP2735293B2 - Inorganic moldings reinforced with reticulated moldings - Google Patents

Description

The present invention relates to structures used in the field of civil engineering and construction, in particular roofs,
In connection with fiber-reinforced inorganic plates used as plate-like structures such as walls, floors, and pits, the adhesion of the reinforcing fibers to the matrix is improved without impairing the tensile properties such as the tensile strength and elastic modulus of the reinforcing fibers. The physical property of the fiber-reinforced inorganic molded article is measured by using a reticulated molded article capable of effectively exhibiting the tensile properties of fibers for use as a reinforcing material.

2. Description of the Related Art Conventionally, various proposals have been made for a fiber-reinforced inorganic plate, and as a reinforcing material, a fiber-reinforced inorganic plate in which short fibers are randomly oriented, and a fiber reinforcement in which continuous fibers are oriented in one direction or two directions and laminated. Inorganic plates are known (Kashima Institute of Construction Technology Annual Report No. 29, pp. 81-88, and 30
No. 57-68, JP-A-59-138647).

A fiber-reinforced inorganic plate cannot provide a reinforcing effect commensurate with the strength of the reinforcing material unless the bonding strength between the fiber as the reinforcing material and the inorganic material as the binder is sufficient. This problem is particularly important when high strength reinforcements or fiber bundles are used. That is, when used in a carbon fiber of 80 kgf / mm ² as low strength of short fiber monofilaments,
Since the surface area of the fiber is larger than the cross-sectional area of the fiber, the reinforcing effect is exerted until the fiber breaks when a tensile stress is applied. However, when high-strength fibers or fiber bundles are used, the fibers come off, and a reinforcing effect corresponding to the original tensile properties of the reinforcing fibers cannot be obtained.

In order to improve this, it has been proposed that a continuous high-strength fiber is formed into a net-like woven fabric having a strong intersection-binding force, for example, a tangled woven fabric, a resin-impregnated net-like molded body, and then placed in a cement mortar. (JP-A-63-1111045, 63
-22636). However, at present, the tensile properties of the fibers of the woven fabric, that is, the tensile strength, the elastic modulus, etc., have not been fully utilized.

Problem to be Solved by the Invention The present invention solves the drawbacks of the conventional fiber-reinforced inorganic molded article reinforced by a net-like woven fabric, and is reinforced with a net-like molded article so that the original tensile properties of the reinforcing material can be exhibited more. An object is to provide an inorganic molded article.

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that it can be achieved by using a special net-like woven fabric as described below. Was completed.

The present invention relates to a fiber-reinforced inorganic molded article containing, as a reinforcing material, a reticulated molded article in which the intersection of the reticulated textiles or the entire textile is fixed with a resin, and a reticulated molded article serving as a reinforcing material in a fiber-reinforced inorganic molded article having an inorganic cured material as a matrix. By using a woven fabric having at least a twist of 0.5 to 7 turns / inch in the number of twists of the yarn used for at least the weft and / or warp, a matrix is formed while taking advantage of the tensile properties of the reinforcing material. A fiber-reinforced inorganic molded article, characterized in that the adhesion to the fiber-reinforced inorganic molded article is improved.

In addition, as a net-like woven fabric, there are an entangling machine and a mosaic weave, and an entangling machine is a typical example.

That is, in the fiber-reinforced inorganic molded article of the present invention, a thread formed by twisting the fiber to such an extent that the tensile properties of the fiber is not impaired is used as a net-like woven fabric used for at least a weft and / or a warp, and a net-like molded article fixed with a resin is used. By using the reinforcing material, the adhesion of the reinforcing material to the matrix is improved, and the tensile properties are sufficiently exhibited, thereby improving the mechanical properties of the fiber-reinforced inorganic molded article.

Hereinafter, before describing the present invention, first, a tangled woven fabric, which is a typical example of a conventional net-like woven fabric, will be described.

In the weaving structure of the conventional entangled fabric, as shown in FIG. 4 (a), a pair of wefts 1 and 1 'are entangled with each other.
Further, as shown in FIG. 4 (b), the warp 3
1 'receives a force in the length direction and is crimped. Conventionally, a reticulated body used for a fiber-reinforced inorganic molded body is obtained by fixing such a reticulated fabric with a resin. When a load is applied to the molded body alone, the fiber is fixed with resin, so when the load increases, local strain and stress concentration are likely to occur in the bent portion, and the fiber does not exhibit 100% tensile properties. Destruction will occur at the bent part in the meantime.

Further, when this reticulated molded product is used for a fiber-reinforced inorganic molded product, the reticulated molded product arranged at the position receiving the tensile stress shares the tension. With the increase of the force, a force acts in the direction of arrow 5 in FIG. 4 (c), and a function to break the interface between the reticulated body and the matrix occurs. In other words, carbon fiber, aramid fiber, etc., which have excellent corrosion resistance, have the advantage that the cover thickness of the mortar can be reduced as compared with rebar, but as the tensile stress increases with respect to the reticulated molded body having a bent portion, The mortar peels off, and the fixing power of the reticulated molded product is reduced. As a result, the fiber-reinforced inorganic molded product is destroyed before the fiber exhibits sufficient tensile properties.

On the other hand, FIG. 1 (a) shows a case of a net-like woven fabric using a reticulated yarn in which the number of twists of yarn used for the weft is 0.5 to 7 turns / inch. It is shown in FIG.

Furthermore, the warp and the weft have a twist of 0.5 to 7 turns /
FIGS. 2 (a) and 2 (b) show the case of a net-like woven fabric using a stranded yarn in the inch range.

In this case, the warp of the reticulated molded body is composed of two or more kinds of yarns of high rigidity warp 1 and low rigidity warp 2 having different rigidities, and the weft is composed of a high rigidity weft twisted yarn 3.

When a non-twisted fiber bundle is used as in a conventional net-like woven fabric, the cross-section of the fiber bundle is sandwiched by warps and the cross-section of the fiber bundle becomes flat, resulting in a net-shaped molded body having a bent portion. Even afterwards, the cross section of the fiber bundle is rounded without flattening, the rigidity can be given to the fiber bundle itself, the bent part is reduced, and if the fiber bundle itself is subjected to a tensile tension by using a twisted yarn, the fiber bundle itself becomes Tend to tighten,
Unlike the case of the non-twisted yarn, a reticulated molded body with improved physical adhesion is obtained, instead of destroying the interface with the matrix.

Next, the number of twists of the twisted yarn will be described with reference to FIGS. 3 (a) and 3 (b).

Here, 3,000 carbon fibers having a tensile strength of about 280 [kgf / mm ² ] and a tensile elasticity of about 20 [tonf / mm ² ] (hereinafter 3
Using two non-twisted yarns (abbreviated as k), a twin-twisted yarn was prepared, and then impregnated with resin to prepare a stick for a tensile test and a stick for an adhesion test.

The tensile test was measured according to JIS R 7061 "Carbon fiber test method". For the adhesion test, a test piece (embedded length on the pull-out side: 10 mm, 4 sticks) as shown in Fig. 3 (a) was prepared and measured according to JCI-SF8 "Fiber adhesion test method". Was done. The adhesion strength was indicated by a load value per unit length. The result of the measurement is shown in FIG. In the case of this twin-twisted yarn, the tensile strength (■ mark) and the elastic modulus (●
(Mark) is 3 turns / inch or more, a remarkable decrease in physical properties was observed.

On the other hand, the adhesion strength (▲) was 3 turns / inch
Thus, the stick has been pulled out due to the shear fracture of the matrix.

That is, at 3 turns / inch or more, impact resistance (breaking energy) due to interfacial fracture between the matrix and the stick decreases.

Therefore, the case of the above-mentioned twin-twisted yarn of carbon fiber is given as an example of the ply twist, but the number of ply twists varies depending on the fiber used, the number of fiber bundles, the member used for the fiber-reinforced inorganic molded article, and the purpose. Is in the range of 0.5 to 7 turns / inch, preferably in the range of 1 to 4 turns / inch.

The high-rigidity yarn used for the reticulated molded body needs to have high strength, for example, high-strength carbon fiber, aramid fiber,
Examples include alkali-resistant glass fibers and high-strength vinylon fibers.

Further, the number of filaments and the number of strands of the above-mentioned carbon fiber, aramid fiber, alkali-resistant glass fiber, high-strength vinylon fiber, and the like, that is, the cross section of the stranded yarn are as shown in FIG. 3 (c). Cross-sectional structure. However, the limit of the cross-sectional diameter is
It depends on the capacity of the loom, that is, the cutting of the woven portion of the fabric, and the specifications of the guide section through which the yarn passes.However, the specifications of the loom can be changed depending on the member used and the purpose of the fiber-reinforced inorganic molded body. That is good.

The weave density of reticulated fabrics is generally coarse. For example, when an aggregate-containing cement is used as the inorganic material matrix, the opening is set to 3 to 50 mm, preferably about 3 to 30 mm in consideration of the fact that the particle size of the aggregate (2 to 25 mm) can pass through the reticulated molded body. It is desirable to set the interval.

The resin for fixing the net-like woven fabric is impregnated into the woven fabric by an appropriate means, for example, dipping, spraying or the like.
It is preferable to use a known prepreg manufacturing apparatus. As the resin, a thermosetting resin is preferable, and specifically,
Epoxy resin, urethane resin, phenol resin, polyimide resin and the like can be mentioned. When a cement is present as a component of the inorganic material used as the matrix, it is preferable that the cement has long-term durability against alkalinity, and furthermore, the strength is less reduced even after autoclaving at about 180 ° C. for about 5 hours. Is preferred. The impregnated resin is subjected to a thermosetting treatment, but since this is performed to maintain the form of the woven fabric, it is necessary that at least the resin does not flow, that is, a so-called C stage state,
Complete curing is not necessary. However, from the viewpoint of product stability, it is preferable that the curing has progressed as much as possible.

As the inorganic hardening material used to constitute the matrix in the present invention, Portland cement, ordinary cements such as blast furnace cement, calcium silicate-based compounds composed of calcareous and siliceous, gypsum (semihydrate gypsum, anhydrous gypsum and the like), Blast furnace slag and various binders such as granulated slag-based hydraulic material such as a mixture of slag crushed slag and gypsum, and water, if necessary, natural or artificial aggregate (particle size: 2 to 25m)
m), an admixture, and a mixture obtained by kneading the admixture.

The reticulated woven fabric obtained as described above is arranged at a position where a tensile stress is applied to the inorganic molded article as a product, and a matrix material is poured and cured to obtain a fiber-reinforced inorganic molded article. The type, the strength, the elastic modulus, the number of filaments, the number of strands, and the like of the high-rigidity fibers to be used may be determined according to the target strength of the molded product. As the molded article of the present invention, a plate-like article in which a net-like molded article is embedded near the surface is particularly preferable.

As in the case of the fiber-reinforced inorganic molded article of the present invention, a twisted yarn that does not impair the tensile properties of the fiber is used as a net-like woven fabric used at least for the weft and / or the warp,
By using a reticulated molded body fixed with resin as a reinforcing material,
By improving the adhesion of the reinforcing agent to the matrix and sufficiently exhibiting the tensile properties, the mechanical properties of the fiber-reinforced inorganic molded body are improved.

Examples Example 1 As a high rigidity fiber, the tensile strength is about 380 [kgf / m].
m ² ], a carbon fiber with a tensile modulus of about 20 [tonf / mm ² ]
Using two 2,000 (hereinafter abbreviated as 6k) twin-twisted yarns with a twist of 2 turns / inch, the weaving density is 3.3 yarns / 25mm together with the warp and weft, and FIG. And (b)
A net-like woven fabric having the structure shown in Table 1 was produced. The woven fabric was impregnated with an epoxy resin having the following formulation, and dried and cured at 150 ° C. for 15 minutes. The amount of the resin was about 40% based on the weight of the cured molded body.

Bisphenol A type epoxy resin (GY-260, manufactured by Ciba Geigy) 100 parts Dicyandiamide 10 parts Imidazole type accelerator (Curesol 2P4MHZ, manufactured by Shikoku Kasei Co., Ltd.) 2 parts Solvent (methyl cellosolve) 120 parts Net obtained in this manner The molded body contains two warps or wefts, and the matrix material having the following composition is weighed so as to be at the center position of 10 mm in thickness, and the matrix paste obtained by kneading is poured into a mold and molded. Was carried out to prepare a tensile test piece (parallel portion thickness: 10 mm, length: 50 mm) as shown in FIG. The obtained molded body is
Cured in water at 20 ° C for 14 days.

Matrix composition: Normal Portland cement 100 parts by weight No. 8 silica sand 50 parts by weight Water 50 parts by weight In the tensile test, the loading speed was 0.5 mm / min, and the displacement meter was a 20 mm pie type displacement meter attached to the parallel part.

Further, for comparison, a tensile test piece was prepared from a mesh fabric as shown in FIG. 4 (a) in the same manner as described above, and a tensile test was performed.

The load-displacement curves obtained in the tensile test are shown in FIGS. 6 (a) and 6 (b). The four curves 11, 12,
13 and 14 correspond to:

11: The mesh fabric of the present invention in which the warp is in the pulling direction 12: The mesh fabric of the present invention in which the weft is in the pulling direction 13: The conventional mesh fabric having the warp in the pulling direction 14 ··································································· The fiber-reinforced inorganic molded article using the reticulated fabric of the present invention in the warp direction (11) or weft direction (12)
In any case where the tension is set in the tensile direction, the fiber has sufficient tensile properties without delamination failure between the mesh and the matrix, compared to the molded body (13, 14) using the conventional mesh fabric as a reinforcing material. And exhibited high tensile strength.

On the other hand, in the case where the reticulated woven fabric according to the present invention shown in FIGS. 2 (a), (b) and (c) is used as a reinforcing material, delamination destruction between the reticulated molded body and the matrix is performed in the same manner as in Example 1. The fiber exhibited the tensile properties sufficiently and exhibited high tensile strength without occurrence.

Furthermore, not only in the case of the twin twisted yarn, even when the reinforcing material is a net-shaped molded body using three or more brittle yarns,
As in Example 1, the fibers used sufficiently exhibited the tensile properties and exhibited high tensile strength without causing delamination between the reticulated body and the matrix.

Effect of the Invention The reinforcing material is a net-like molded product obtained by fixing a net-like woven fabric using a yarn twisted to such an extent that the tensile properties of the fibers are not impaired with a resin, and the fiber-reinforced inorganic molded product of the present invention is a matrix of a reinforcing material. To improve the mechanical properties of the molded article.

[Brief description of the drawings]

FIGS. 1 (a), 1 (b) and 1 (c) are a plan view, a cross-sectional view and an action diagram of a force when a reticulated body is subjected to a tensile stress, of an example of a reticulated woven fabric according to the present invention. 2 (a), 2 (b) and 2 (c) are a plan view, a cross-sectional view and an action diagram of a force when a net-like molded body is subjected to a tensile stress, as an example of a net-like woven fabric according to the present invention. FIGS. 3 (a), (b) and (c) are schematic diagrams of test pieces for determining the number of twisted yarns of the present invention, tensile strength, elastic modulus, and cement of twisted sticks according to the number of twisted yarns. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the adhesive strength with respect to a matrix, and a figure which shows the cross-section example of a friable twisted yarn. FIGS. 4 (a), (b) and (c) are a plan view and a sectional view of a conventional net-like woven fabric, and an action diagram of a force when the net-like molded body receives a tensile stress. FIG. 5 is a schematic view of a tensile test piece. FIGS. 6 (a) and (b) are load-displacement curves in a tensile test of a fiber-reinforced inorganic molded article reinforced with a net-like molded article. 1, 1 '... high rigidity warp yarn (Fig. 1), high rigidity warp yarn (Fig. 2), 2 ... low rigidity weft yarn, 3 ... high rigidity weft yarn (Figs. 1 and 2) , A high-stiffness weft thread (Fig. 4), 4 ... a tensile stress acting on the reticulated body, 5 ... a stress direction generated when a tensile stress is applied to the reticulated body, 6 ...
... twin twist stick, 7 ... cement matrix, 8
...... Teflon plate, 9 ...... Reticulated molded article of the present invention and conventional reticulated woven fabric fixed with resin, 11 ...... Reticulated woven fabric of the present invention with warp pulled in direction, 12 ...... Reticulated woven fabric of the present invention 13: a conventional mesh-like woven fabric having a warp in a pulling direction, 14: a conventional mesh-like woven fabric having a weft in a pulling direction.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kanji Yamada 1618 Ida, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture New Technology Research Institute No. 1 (72) Inventor Shinichi Inaba 1548 Kamikoizumi, Oizumi-cho, Okura-gun, Gunma Prefecture No. 109 (72) Inventor Yasuyuki Shinto 1820 Yoshida, Oizumi-cho, Euraku-gun, Gunma Prefecture (72) Inventor Shiro 2343, Yoshida, Oizumi-cho, Ouraku-gun, Gunma Prefecture (72) Inventor Hironori Naganuma 5-chome Kitaurawa, Urawa City, Saitama Prefecture 15 No. 39, No. 819 (56) Reference JP-A-2-243546 (JP, A)

Claims (2)

(57) [Claims] An inorganic molded article containing a reticulated molded article in which a reticulated woven fabric is fixed with a resin as a reinforcing material and reinforced with a reticulated molded article having an inorganic cured material as a matrix, used for the weft and / or warp of the reticulated woven fabric. An inorganic molded article reinforced with a net-like molded article, characterized in that the number of twists of the pliable yarn is in the range of 0.5 to 7 turns / inch. 2. A method according to claim 2, wherein a part or all of the yarns constituting the net-like woven fabric are carbon fibers, aramid fibers, alkali-resistant glass fibers,
The inorganic molded article reinforced by the reticulated molded article according to claim 1, wherein the inorganic molded article is made of at least one of high-strength vinylon fibers.