JPH0343551A - Lattice-shaped reinforcing material for hydraulic substance - Google Patents

Abstract

PURPOSE:To improve the reinforcement and the execution workability by utilizing mechanical performance and toughness (Young's modulus), which are provided in fiber, and knitting the fiber to be woven in a knotless net to form a lattice state while performing impregnation work with resin. CONSTITUTION:A cord is constituted of an organic synthetic fiber filament of PVA or PA system, consisting of single fiber, or of a mixed fiber filament yarn which consists of the organic synthetic fiber filament and a filament of inorganic fiber of glass fiber, steel fiber, alumina fiber, etc. Here a single fiber denier of 0.5 to 25dr with tensile strength 9g/denier(dr) or more and Young's modulus 200g/dr or more is used further with a diameter of the cord in a range of 3 to 10mm. The fiber is knitted and woven to a knotless net of 20 to 200mm as a distance between points of intersection, impregnated with resin and hardened by performing heat treatment.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is a lattice-shaped reinforcing material that is self-supporting against hydraulic substances such as cement mortar and concrete, and is suitable for use as a civil engineering material in tunnels and slopes. The present invention relates to a lattice-shaped reinforcing material that can be used as a reinforcing material for linings, and as a reinforcing material for building materials such as boards.

<Prior Art and Problems to be Solved by the Invention> Reinforcing bars have traditionally been used as structural materials in civil engineering work, building construction work, or building materials, and are stipulated in JIS G3112 and JIS G3117.

Reinforcing bars have various features in terms of performance, construction, and economy, and are used in large quantities. However, there are major drawbacks in terms of current design and construction. If it shows the shortcomings from the material that require improvement.

This is because the reinforcing bars themselves have a high specific gravity, which makes them difficult to handle.Furthermore, when used as parts, reinforcing bars require a certain thickness of cover to prevent rusting, so they cannot be used as parts. The thickness of the material becomes thicker, and the weight of each member also increases.

26 Rust may occur. Rainwater due to micro cracks,
Deterioration of members occurs due to the formation of rust on the reinforcing bars due to the inflow of salt water, salt in the cement aggregate, and the generation of batteries at the poles due to the magnetic field and electric field at the ground level.

3. Has electrical conductivity and magnetization.

Also, if you show the drawbacks in terms of construction.

1. Reinforcement of lattice-like objects in planar construction takes a lot of effort to assemble, and is inferior in productivity and workability.

2. When extending for use inside tunnels or for slope lining, reinforcing bars have poor conformability in order to conform to the unevenness of the surface of the ground, requiring a great deal of labor and poor workability.

3. Since a cover thickness greater than a predetermined value is required, it is necessary to position it, and reinforcement assembly is required.

4. It is not easy to cut the reinforcing bars in the reinforcement and construction layers.

Special cutters and fusing are required.

5.7i, so safety during work is inferior.

Examples include.

Some lattice-like objects made of materials other than reinforcing bars are commercially available, in which straight glass fibers are bundled with resin. However, even though the glass #R1g is heavy, it is difficult to handle. Moreover, there remains a problem in alkali resistance in cement. Since the lattice-like material is made of solid glass fiber, it is rigid, so when used as a reinforcing material for lining the inner surface of tunnels and slopes, it does not conform to the unevenness of the ground like a reinforcing bar lattice-like material, so it is difficult to construct. The work at the time is also difficult. Furthermore, glass fiber is brittle and has poor impact resistance, and when lining the inner surface of a tunnel or slope with mortar spraying, the impact force of the aggregate will damage the joints, making it useless as a reinforcing material. It also has the disadvantage of

Means for Solving the Problems> The present inventors have conducted research on techniques to eliminate the drawbacks of grids using reinforcing bars and glass fibers.
Mechanical performance and hip strength (Young's modulus) of 5iua
Taking advantage of this, we knit them into a knotless net to form a lattice-like object, and then impregnated with resin, which gives it impact resistance and bending strength as a self-supporting reinforcing material, and is also light in terms of construction. We have discovered a grid-like reinforcing material for hydraulic materials such as cement mortar and concrete that has excellent workability and can be safely installed without damage during spraying work.

The present invention uses polyvinyl alcohol (hereinafter referred to as PV
A) type or fully aromatic polyester (hereinafter abbreviated as PA)
and other organic compounds such as polyester, polyolefin, polyamide, aramid, etc. +1 & 111. A cord consisting of a filament made of fibers, or a mixed filament yarn made of these organic synthetic fiber filaments and filaments of inorganic fibers such as glass fiber, carbon fiber, alumina fiber, steel fiber, etc.
A lattice-like reinforcing material for a hydraulic material comprising a knotless net whose cords have a diameter of 3 to 10 fi and a distance between intersections of 20 to 200 fi, and a binder resin impregnated into the cords and hardened. , preferably the tensile strength of the cord including the intersection point is 20 kf/- or more, and the Young's modulus is 100
This is a lattice-like reinforcing material for hydraulic materials having a resistance of 0 kf/- or more.

Listing the features of the reinforcing material of the present invention, from the point of view of reinforcing properties without residue, (1) the twisted cord of fibers with high strength and high Young's modulus is treated with resin, so it has good adhesion with cement and provides high reinforcement; Effects can be obtained. (2) Since it is a knotless network, the intersection strength is high and a high reinforcing effect can be obtained. (8) Since it is woven in a lattice pattern, a reinforcing effect in two directions can be obtained. Next, from the viewpoint of workability, (1) since the fibers have excellent impact resistance, spraying does not cause damage or deterioration due to aggregate in the concrete. (2) Workability during installation is good due to its excellent self-standing and shape-forming properties. (8) Since it is lightweight, transportation and installation are easy and safe. (4) The lattice-like object is self-supporting and can be handled as a scroll, making it easy to transport.
In addition, the storage space is small, and since it is endless, there is no need for complicated additions. (5) It can be easily cut with a simple cutting tool such as a saw or pliers.

There are many construction advantages. Furthermore, from an economic point of view, it can be easily produced in large quantities and is inexpensive. As described above, since it has features in terms of reinforcing properties, workability, safety, and economic efficiency, it can be suitably used as a reinforcing material for hydraulic substances.

The synthetic fiber used in the present invention has a tensile strength of 9 f/dr.
Above, the Young's modulus must be 2oOr/dr or more, and the tensile strength and Young's modulus must be less than 9y/dr, 200
If the ratio is less than y/d r, the reinforcing material cannot exhibit sufficient performance. The fineness of the synthetic fiber used in the present invention is in the range of 0.5 to 25 dr, preferably 1.5 dr.
~15 dr. If it is less than 0.5 dr, the impregnating property of the resin will deteriorate when it is made into a cord, which is unfavorable. On the other hand b2
If it exceeds 5 dr, fibers with high strength and high Young's modulus cannot generally be obtained, and cord strength and rigidity cannot be obtained.

Among the synthetic fibers used in the present invention, PVA fibers and PA fibers are particularly preferred.
A-type composite fibers are preferably those using PVA with a degree of polymerization of 1,000 to 20,000 and a degree of saponification of 98 moles or more, and naturally the tensile strength of the fibers is 9 y/dr or more and a Young's modulus of 200 y/dr. lir or higher is required. More preferably, it has a tensile strength of 13 to 305'/dr and a Young's modulus of 250 to 1000 y/dr.

A PA-based compound is an aromatic polyester that can be melt-processed by condensation of one or more aromatic hydroxy acids, optionally with an aromatic diol and/or an aromatic diacid, in which each component present It is a wholly aromatic polyester, which is called wholly aromatic in the sense that at least one aromatic ring of the A fiber made of aromatic polyester. Among these wholly aromatic polyesters, polyesters of hydroxybenzoic acid, especially p-hydroxybenzoic acid and 6-hydroxy-2-naphthoic acid, and polyesters copolymerized with p+T''-bisphenol as a third component. Besides, p-
Polyesters consisting of hydroxybenzoic acid, p, p'-biphenyl, terephthalic acid layers and/or high isophthalic acid are particularly useful, but are not limited to This does not preclude the introduction of other components into the polymer unless otherwise specified.

Generally, when these PA fibers are heat treated in air at 290°C for 24 hours, the filament strength is 15%.
F/dr or more, elongation 6% or less, Young's modulus 400y/4r
You can get more than that. In particular, monomers whose main component is a copolymer of p-hydroxybenzoic acid and 6.2-hydroxynaphthoic acid have a strength of 20 f/llr or more, an elongation of 4% or less, and a Young's rate 50
It is preferred in the present invention because it has a physical property of 0f/dr.

Other organic synthetic fibers include polyolefin synthetic fibers such as polyethylene fiber and polyethylene fiber, and polyamide synthetic fibers such as nylon 6 and nylon 6.
．． 6 and the like can be used as polyester-based synthetic fibers, industrial filaments such as polymerized polyester, and rose-based wholly aromatic polyamides represented by Kepler can be used as aramids. In the present invention, one synthetic fiber must be in the form of a filament, and short IIL fibers cannot achieve the desired purpose in terms of strength.

No 41! Typical examples of fibers include glass fibers,
Examples include alkali-resistant glass fiber, general E-glass fiber, and high-strength glass fiber (T-glass). As the carbon fiber for the housing, PAN type or pitch type carbon fiber obtained from polyacrylonitrile can be used. Alumina fiber is S
It is a mixture of iOz and A-t203, but A1.20
Those with a high s content are Alxm fibers, and those with a high 5iOz content are silica fibers or slag fibers, and both of these can be used in the present invention. Steel fI1. As the fibers, drawn and thinned steel fibers can also be used. However, although these inorganic fibers are satisfactory in terms of high strength and high Young's modulus, they have problems with impact resistance, alkali resistance, rust, etc., and it is difficult to use them alone, so they can be mixed with organic synthetic fibers. It exhibits synergistic effects in terms of reinforcement, impact resistance, and lightness. The volume mixing ratio of inorganic fibers and organic synthetic fibers is 0 to 50:100, respectively, depending on the application.
50 is preferred.

In the present invention, the cord is usually formed by twisting a plurality of multifilament yarns, but the denier of the multifilament yarns is 50.
0 to 30,000 is preferable.

When knitting a knotless net, the diameter of the cord needs to be in the range of 3 to 10 square centimeters. If it is less than 3 gourds, it is not suitable from the viewpoint of reinforcing properties. If the length exceeds 10 m, it becomes difficult to weave a knotless net. The cord diameter referred to in the present invention is obtained by laying the cord under no tension, measuring the diameter without applying pressure, and calculating the average value. The number of twists for the first and second twists of the cord has a suitable range from the viewpoint of resin impregnation, intersection strength, and adhesive strength with cement due to irregularities on the cord surface, and the number of twists for the first twist is 30~ 250 times/m (times/m is 1
(number of twists per m) is preferably 50 or more, more preferably 50~
The number of first twists is preferably 30 to 200 times/m, more preferably 50 to 150 times/m.

The distance between the intersections of the knotless network is 20 to 200 parrots. Although the cord thickness varies depending on the application and the part of the member, it is preferable that within the above range, when the cord thickness is thin, the distance between the intersection points is small, and when it is thick, it is large. In addition, when using fine aggregate, it is preferable that the distance between the intersection points is less than
The above is preferable. When substituting reinforcing bars for side walls and the like in factory-produced concrete products, generally a method is used to increase the volume content of the reinforcing material by using a plurality of grids of the present invention or by reducing the distance between intersection points.

In addition, when used for lining the inside of a tunnel or a slope, the distance between the intersections that allows for the degree of unevenness of the ground surface and the contouring properties of the ground is used. There are various types of knotted structures for making cords into net-like objects, but in the present invention, the net must be knotless in terms of strength at the intersections.

Next, when impregnating the knotless net with resin and heat-treating it,
Resins used for impregnation include unsaturated polyester,
Examples include epoxy resins, vinyl ester resins, urethane resins, acrylonitrile resins, melamine-formalin resins, and phenol resins.

In particular, from the viewpoint of resin impregnation into the cord, low viscosity ones, such as those with a viscosity of 10 to 100 cm (at room temperature and B
(measured with a type viscometer) is better. ! unsaturated polyester,
It is possible to add a curing accelerator to epoxy-based, vinyl ester-based, urethane-based resins, and heat-cure them with hot air at 80 to 180°C or on hot rolls, but acronitrile-based, melamine-based resins Formalin-based, phenol-based, etc., require further heat curing after moisture drying.

Tree, □ Impregnation process. '& (Y, 6 □ 4.1 pieces. After impregnating the A-shaped fabric into a resin tank and controlling the amount of adhering resin with a squeezing roll, grip both edges of the resin-impregnated grid fabric and press it into the specified position. Heat treatment is performed under the tension of , and after cooling, the cord is wound up or cut into a predetermined length.The amount of resin adhered is preferably 20 or more with respect to the total volume of the cord and resin.If the rate of attachment is less than 20φ, the cord is formed. The adhesion between the fibers is low, and the strength of the knotless intersections is also poor, making it difficult to obtain self-supporting properties.
There are over 40. The tensile strength of the cord after resin impregnation is 20
kg/- or more is preferable from the point of view of reinforcing properties, and the elastic modulus is also preferably 900 kt/mj or more for the same reason.

<Function> The lattice-like reinforcement material for hydraulic materials of the present invention can be used to
As an alternative material for ## reinforcing grids, it has superior mechanical performance, durability, workability, safety, workability, and economy than these grids, and can be used as a flat material for various purposes. It can be used as a reinforcing material. In particular, for civil engineering and construction, reinforcement materials for shotcrete for inside tunnels and slope lining,
It can also be used as a reinforcing material for cast-in-place mortar concrete. It can also be used as a reinforcing material for factory production of secondary concrete products such as partitioning boards, siding materials, flooring materials, ceiling materials, etc.

When used in concrete structures such as rails for motor cars, it is particularly effective as it is non-magnetic, non-conductive, and non-rusting.
It can also be used for structures, marine civil engineering, etc. On the other hand, it can also be used as a reinforcing material for materials with low strength and high water permeability, such as lightweight concrete. Furthermore, it can also be used in combination with reinforcing bars.

The present invention will be explained below with reference to Examples.

Examples 1 to 3 PVA with a degree of polymerization of 1700 and a degree of saponification of 99.9-r-le%
PVA shown in Table-1 by wet spinning from an aqueous solution
A fiber multifilament was obtained (referred to as filament A).

Similarly, the degree of polymerization is 4400. A PVA fiber multifilament shown in Table 1 was obtained by wet spinning from a PVA* solution with a saponification degree of 99.9 mol (filament B).
).

A molten liquid crystal polymer consisting of a copolymer of p-hydroxybenzoic acid and 6-hydroquine-2-naphthoic acid was melt-spun to obtain a spun yarn of 1500 dr/300 f. Further, heat treatment was performed in air at 290°C for 24 hours to obtain the aromatic polyester fiber multifilament shown in Table 1.
(referred to as filament C).

Table 1 Using the above filament A to C, the first twist b and the second twist were applied in the configuration shown in Table 2 to knit a knotless net with corners having a distance of 12 between intersections. Table 2 shows the total denier used, the diameter of the cord obtained, and the tensile strength, strength, and Young's modulus of the cord. Furthermore, the knotless network of each fiber obtained was coated with epoxy resin (Yuka Shell Epoxy Co., Ltd. Epicoat 82B).
It was impregnated in a tank containing a resin liquid with a viscosity of 30 centimeters and a curing accelerator added, and squeezed with a mangle. While holding the ears with a bottle cheater, it was heat-cured in hot air at 150°C for 5 minutes to form a lattice shape. I got something. The amount of resin deposited is shown in Table-3. Table 3 shows the tensile strength, strength, and Young's modulus of the obtained cord diameter cord.
J′
It was very light at 809. Therefore, it was easy to transport, and the grid-like objects could be easily cut with a saw or bench, making it very easy to handle.

For comparison, a 12 cIn square lattice was made from wire with a diameter of 4.4 m, but its average weight was 1700 y/d, which was about 6 times heavier than in Examples 1 to 3. It had to be cut with a saw, and was not handled well.

Examples 4-9. Comparative Examples 1 and 2 The reinforcing effects of the lattice-like materials of Examples 1 to 3 as reinforcing bars in the cement matrix and those (plain) in which no reinforcing bars were used as Comparative Examples 1 and 2 were investigated.

Cement mortar and lightweight cement mortar were used as the cement matrix. When measuring the bending strength, the reinforcing bars were arranged by placing two lattice-like members of Examples 1 to 3 at a thickness of 10 mm from the surface facing the tensile strength. The reinforcement ratio is shown in Table 4. The cement mortar composition includes 100 parts of early strength cement (abno early strength cement) (all parts by weight hereinafter), 300 parts of silica sand (inkstone silica sand No. 6.5), and 150 parts of gravel (Okayama Asahikawa 5 grain size or less). After weighing and dry-mixing for 1 minute using an omni mixer, 52 parts of water and 2.5 parts of a water reducing agent (Kako Mighty 150'') were added and mixed for 2 minutes to obtain a mortar.The composition of the lightweight cement mortar was as follows: Add 100 parts of early strength cement (Asano early strength cement), 10 parts of finely powdered pearlite (Ube 1 type), and an expanding agent (1!Denka C3A φ20, manufactured by Ki Kagaku Kogyo Co., Ltd.), and dry mix for 1 minute in an Omni 2 mixer. 3 parts of a foaming agent (Formix C2 manufactured by Hamano Kogyo Co., Ltd.) and 1 part of a water reducing agent were added and mixed for 2 minutes using an omnimixer to obtain a mortar.

For molding, a mold having a thickness of 10 cm, a length of 40 crm, and a width of 40 cm was used. That's what doesn't require reinforcement! The same formwork as S was used.

Pour the corresponding mortar milk into the mold and mold it, -
After being left to harden overnight, the molds were removed, and those containing cement mortar were cured in water for 4 weeks, and those containing lightweight cement mortar were left to cure for 4 weeks at 1\6% room temperature at 25°C.

The bending strength was measured using a Shimadzu universal testing machine. The span length is 30, and the maximum breaking load is the central loading method.
The deflection was measured. Bending strength (where P is load, L
is the span length, b is the width of the member, and t is the thickness of the member). It is shown in Table-4.

Table-4

Claims (1)

[Claims] It consists of cords with a diameter of 3 to 10 mm, and the distance between intersections is 20 mm.
A lattice-like reinforcing material consisting of a knotless net of ~200 mm and a binder resin impregnated into the cord and hardened, the cord has a tensile strength of 9 g/denier or more, a Young's modulus of 200 g/denier or more, and is a single fiber. Denier is 0.
A lattice reinforcement material for hydraulic materials composed of synthetic fiber filaments of 5 to 25 deniers.