JP2003246655A - Frp rod as alternative to reinforcing steel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive FRP rod which has an high initial mechanical strength, whose mechanical strength hardly lowers even when an alkaline substance infiltrates into a matrix resin and which can be used as an alternative material to reinforcing steel without causing lowering of the mechanical strength of a PC structure. <P>SOLUTION: The FRP rod is obtained by using, as a reinforcing material, a glass fiber formed from glass characterized in that the ratio of the mass loss of the powder of the glass, having particle diameters of 300 to 425 μm, after being dipped in 10 mass % aqueous solution of sodium hydroxide and heated at 80°C for 16 h is ≤1.0 mass %, and the alkali elution amount is ≤0.10 mg when measured according to JIS R 3502. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a FRP (fiber reinforced plastic) rod using glass fiber as a reinforcing material, which is excellent in alkali resistance and in which alkali metal ions are difficult to elute. The present invention relates to an FRP rod suitable as a material.

[0002]

2. Description of the Related Art Precast concrete (P
C) Reinforcing bars have been widely used for reinforcement in structures, but such PC structures have problems such as reduction in mechanical strength due to corrosion of reinforcing bars and radio wave interference due to reinforcing bars which are metallic materials. However, since the recent demands for civil engineering materials and building materials are to reduce the weight and increase the strength of PCs, it has become impossible to satisfy the demands with reinforcing bars.

Under such circumstances, an FRP rod made of a thermosetting resin reinforced with fibers has been attracting attention as a substitute material for reinforcing bars. The FRP rod is more resistant to corrosion than rebar and has a high tensile strength, so that the mechanical strength of the PC structure can be increased, the specific gravity is small, so that the weight can be reduced, and the non-magnetic material does not cause radio interference.

By the way, as fibers usable in the FRP rod, there are carbon fiber, aramid fiber, glass fiber and the like which are excellent in tensile strength.

When E glass fiber, which is cheap and widely used among glass fibers, is used as a reinforcing material for FRP rods, the alkaline substance eluted from the cement component corrodes the glass fibers, so that the glass fibers and the matrix resin are separated from each other. Since the strength of the FRP rod is reduced by destroying the adhesion at the interface, the mechanical strength of the PC structure may be reduced if the FRP rod is used as a reinforcing bar substitute material.

On the other hand, alkali resistant glass fibers (AR glass fibers) containing about 10 mol% of ZrO ₂ (for example,
See Patent Document 1. ) Is proposed.

[0007]

[Patent Document 1] Japanese Patent No. 2042048

[0008]

Since the glass fiber disclosed in Patent Document 1 contains a large amount of ZrO ₂ , it has excellent alkali resistance and the glass is unlikely to be eroded by an alkaline substance eluted from cement. Since it contains about 17 mol% or more of oxides and alkali metal ions are easily eluted, when used as a reinforcing material for FRP rods, when the matrix resin of FRP is cured, the alkali metal ions that are often present on the glass fiber surface cause , The adhesion between glass fiber and matrix resin is hindered, and FR
There is a problem that the initial mechanical strength of the P rod becomes low. The initial mechanical strength of the FRP rod means the FRP rod before it is used in a PC structure or the like.
Refers to the mechanical strength of the rod itself.

The object of the present invention is that the mechanical strength of the FRP rod is high at the beginning, and even if an alkaline substance penetrates into the matrix resin, the mechanical strength of the FRP rod does not decrease.
Another object is to provide an inexpensive FRP rod in which the mechanical strength of the PC structure does not easily decrease even when used as a reinforcing bar substitute material.

[0010]

[Means for Solving the Problems] Reinforcing bar substitute FR of the present invention
The P rod is obtained by immersing glass powder having a particle size of 300 to 425 μm in a 10 mass% sodium hydroxide aqueous solution,
When the glass is treated at 80 ° C. for 16 hours, the mass reduction ratio of the glass is 1.0 mass% or less, and the alkali elution amount measured according to JIS R 3502 is 0.10 mg or less. It is characterized by being used as.

[0011]

The function of the FRP rod for replacing the reinforcing bar of the present invention is 300-
A glass powder having a particle diameter of 425 μm is immersed in a 10 mass% sodium hydroxide aqueous solution and treated at 80 ° C. for 16 hours, and the mass reduction rate of the glass is 1.0 mass% or less. Since the glass fiber made of glass having an alkali elution amount of 0.10 mg or less measured according to 1. is used as the reinforcing material, the mechanical strength of the FRP rod does not decrease even when the alkaline substance comes into contact with the glass fiber. The initial mechanical strength of the rod is high,
Even if it is used as a reinforcing bar substitute material, the mechanical strength of the PC structure is unlikely to decrease, and it is inexpensive. That is, 300 to 42
A glass fiber made of glass having a glass mass reduction rate of more than 1.0% by mass when glass powder having a particle size of 5 μm is immersed in a 10% by mass aqueous sodium hydroxide solution and treated at 80 ° C. for 16 hours. When FRP is used as a reinforcing material for FRP rods, when the alkaline substance in the cement comes into contact with the glass fibers, the glass fibers are easily corroded,
The mechanical strength of the rod tends to decrease. Also, JIS
The alkaline elution amount measured according to R 3502 is 0.
FRP glass fiber consisting of more than 10 mg of glass
When used as a reinforcing material for a rod, when the matrix resin is hardened, the alkali metal ions present on the surface of the glass fiber often interfere with the adhesion between the glass fiber and the matrix resin, and the initial mechanical strength of the FRP rod tends to be low. Because.

The mass reduction rate of the glass after the immersion in the alkaline solution and the amount of the alkali elution are determined by crushing the block-shaped glass having a desired glass composition with an agate mortar and using a metal sieve to obtain 300, respectively. ~ 425 μm, 250 ~
The measurement was performed using glass powder having a particle size of 425 μm.

Further, since the FRP rod for reinforcing bar replacement of the present invention uses glass fiber, which is cheaper than carbon fiber or aramid fiber, as a reinforcing material, the manufacturing cost can be kept low.

In the FRP rod for substituting reinforcing bars of the present invention, the glass fiber is one of ZrO ₂ , NbO _5/2 and TiO ₂ which is a component for improving the alkali resistance of the glass in a mole percentage, and ZrO ₂ and NbO _{5 /} Made of glass containing ₂ to 15% by total amount, or 3 to 3% by total amount of ZrO ₂ and TiO _2.
When it is made of glass containing 25%, 300 to 425 μm
Of a powder having a particle size, was immersed in 10 wt% aqueous solution of sodium hydroxide, 80 ° C., 16 h treated when the glass mass loss rate of, be 1.0 mass% or less, also, Li ₂
A glass containing 0 + 15% of O + Na ₂ O + K ₂ O is preferable because the amount of alkali elution measured according to JISR 3502 is 0.10 mg or less. Zr
The more preferable range of O ₂ + NbO _5/2 is 3 to 12%, and the more preferable range of ZrO ₂ + TiO ₂ is 8 to 21.
%. Further, a more preferable range of Li ₂ O + Na ₂ O + K ₂ O is 0 to 10%, and a further preferable range is 0 to 1.
%.

N constituting the glass fiber used in the present invention
The specific composition of the glass containing b is, in mole percent, Si
_{O 2 40~65%, Li 2 O} + Na 2 O + K 2 O 0~1
5%, MgO + CaO + SrO + BaO 20-45
%, ZrO ₂ 0-8%, NbO _5/2 2-12%, Ti
O _{2 is} 3 to 20%, and more preferably SiO ₂ 4.
6 to 60%, Li ₂ O + Na ₂ O + K ₂ O 0 to 10%,
MgO + CaO + SrO + BaO 25-40%, Zr
O ₂ 0-5%, NbO _5/2 2-10%, TiO ₂ 5
~ 15%.

The reason why the composition of the glass containing Nb is limited is as follows.

SiO ₂ is a component constituting the skeleton of glass, and has the effect of improving the alkali resistance and acid resistance of glass, but if it is less than 40%, its effect is small and the devitrification temperature is high. As the spinning viscosity decreases, the glass filament easily breaks during spinning,
Further, it is not preferable because the chemical durability such as alkali resistance is deteriorated. On the other hand, when it is more than 65%, the viscosity of the glass melt becomes high and the melting of the glass becomes difficult, which is not preferable. A more preferable range is 46 to 60%.

Li ₂ O, Na ₂ O and K ₂ O are preferable when the total amount thereof is 0 to 15% because the amount of alkali elution measured according to JISR 3502 is 0.10 mg or less. A more preferable range is 0 to 10%, and a further preferable range is 0 to 1%. However, if these alkali metal oxides are not contained, the alkali metal in the glass does not elute on the glass surface, so that the glass fiber and matrix It is particularly preferable because the adhesion with the resin is not hindered and the initial mechanical strength of the FRP rod is unlikely to decrease.

MgO, CaO, SrO and BaO are modified oxides having a glass structure and act as a fluxing agent, but if the total amount of these is less than 20%, the viscosity of the glass melt becomes high, and However, if it exceeds 45%, the devitrification temperature increases and the spinning viscosity decreases, so that the glass filament is easily broken during spinning, which is not preferable. A more preferable range is 25 to 40%.

ZrO ₂ is a component that remarkably improves the alkali resistance, but if it exceeds 8%, the devitrification temperature becomes high, which is not preferable.

NbO _5/2 is a component that improves alkali resistance and greatly lowers the devitrification temperature.
If it is less than 12%, the alkali resistance is difficult to improve and the devitrification temperature is unlikely to be lowered. If it is more than 12%, the devitrification temperature rises, which is not preferable. Further, it is preferable to use it in combination with ZrO ₂ because the alkali resistance can be efficiently improved without increasing the devitrification temperature.

TiO ₂ is a component that improves the acid resistance and alkali resistance and lowers the devitrification temperature, but when it is less than 3%, the acid resistance and alkali resistance of the glass decrease,
When it is more than 20%, the spinnability is deteriorated, which is not preferable. A more preferable range is 5 to 15%.

There are two types of glass that does not contain Nb which constitutes the glass fiber used in the present invention.
The specific composition of the glass not containing is
O ₂ 46-70%, Li ₂ O + Na ₂ O + K ₂ O 0-15
%, MgO 0-18%, CaO 0-18%, SrO
0-10%, BaO 0-15%, ZnO 0-10
%, MgO + CaO + SrO + BaO + ZnO 11 to 11
35%, ZrO ₂ 2-15%, TiO ₂ 5-18%, and more preferably SiO ₂ 46-65%, Li _2.
O + Na ₂ O + K ₂ O 2-10%, MgO 0-10
%, CaO 0-10%, SrO 0-8%, BaO
5-12%, ZnO 0-5%, MgO + CaO + Sr
O + BaO + ZnO 12~30%, ZrO 2 3~1
2% and TiO ₂ 5 to 15%.

The reason for limiting the composition of the glass not containing the first Nb is as follows.

SiO ₂ is a component constituting the skeleton of glass and has an effect of improving alkali resistance and acid resistance of glass, but if it is less than 46%, its effect is small and the devitrification temperature is high. As the spinning viscosity decreases, the glass filament easily breaks during spinning,
Further, the chemical durability such as alkali resistance is lowered, which is not preferable. On the other hand, when it is more than 70%, the viscosity of the glass melt becomes high and the melting of the glass becomes difficult, which is not preferable. A more preferable range is 46 to 65%.

Li ₂ O, Na ₂ O and K ₂ O are preferable when the total amount thereof is 0 to 15% because the amount of alkali elution measured according to JISR 3502 is 0.10 mg or less. Li ₂ O, Na ₂ O and K ₂ O are components that significantly lower the liquidus temperature in a system that does not contain NbO _5/2 , but if the content exceeds 15%, the alkali metal in the glass will elute on the glass surface. However, the adhesion between the glass fiber and the matrix resin is hindered and the initial mechanical strength of the FRP rod is lowered, which is not preferable. A more preferable range is 2
It is 10%.

MgO, CaO, SrO, BaO and Zn
O is a modified oxide having a glass structure and acts as a flux agent, but MgO is 18% (preferably 10%).
%), CaO 18% (preferably 10%), SrO 10% (preferably 8%), BaO 15% (preferably 5-12%) or ZnO 10% (preferably 5%).
If the amount is larger, the spinnability is deteriorated, and the total amount of these is 1
If it is less than 1%, the viscosity of the glass melt becomes high and the melting of the glass becomes difficult, which is not preferable.
When it is more than%, the devitrification temperature increases and the spinning viscosity decreases, and the glass filament is easily broken during spinning, which is not preferable. A more preferable range of the total amount of these oxides is 12 to 30%.

ZrO ₂ is a component that remarkably improves the alkali resistance, but if it is less than 2%, the alkali resistance is not improved, and if it exceeds 15%, the devitrification temperature becomes high, which is not preferable.

TiO ₂ is a component that improves acid resistance and alkali resistance and lowers the devitrification temperature, but if it is less than 5%, the acid resistance and alkali resistance of the glass decrease, and
When it is more than 8%, the spinnability is deteriorated, which is not preferable. A more preferable range is 5 to 15%.

In addition to the above components, Al ₂ O ₃ ,
It is possible to add up to 5% of B ₂ O ₃ , Ta ₂ O ₅ , La ₂ O ₃ , CeO ₂ , MnO _2, etc., respectively.

The specific composition of the second glass not containing Nb is such that the glass fiber is SiO ₂ 5 in mol percentage.
_{0~60%, Li 2 O + Na} 2 O + K 2 O 0~1%, M
20 to 45% gO + CaO + SrO + BaO, ZrO
₂ 0.1-10%, TiO ₂ 0.5-20%, Al ₂ O ₃
0.1-10%, BaO / CaO in a molar ratio of 0.3-
1.6, and more preferably, the glass fiber has a molar percentage of SiO ₂ 50 to 60%, Li ₂ O + Na ₂ O +.
K ₂ O 0-0.5%, MgO + CaO + SrO + Ba
23-40% O, 0.5-6.5% ZrO ₂ , Ti
_{O 2 6.5~11.5%, Al 2 O} 3 0.2~7.5
% And BaO / CaO are 0.75 to 1.45 in terms of molar ratio.

The reason for limiting the composition of the second glass not containing Nb is as follows.

SiO ₂ is a component that forms the skeleton structure of glass, and its content is 50 to 60 mol%. Fifty
When it is less than 60 mol%, the mechanical strength of the glass is remarkably reduced, and when it is more than 60 mol%, devitrification is likely to occur and glass fiber formation becomes difficult, which is not preferable.

The alkali metal oxide of Li ₂ O, Na ₂ O or K ₂ O is a component for improving the meltability of the glass and a component for adjusting the viscosity of the glass, but their total amount is 0. ˜1%, preferably 0.5%. If the total amount of these exceeds 1%, the elution of alkali metal ions from the glass increases, which is not preferable.

The alkaline earth oxide of MgO, CaO, SrO or BaO is a component that improves the meltability, lowers the viscosity of the glass, and facilitates fiber formation of the glass.
The total amount of MgO, CaO, SrO and BaO is 20 to 4
It is 5%, preferably 23 to 40%. If the total amount of these is less than 20%, the meltability will be poor and the viscosity of the glass will be high, making it difficult to melt the glass. 45
When it is more than%, the devitrification temperature becomes high and it becomes difficult to form glass into fibers, which is not preferable.

The content of MgO is 0 to 15%, preferably 0 to 11%, CaO is 1 to 15%, preferably 4 to 12.5%, and SrO is 0 to 15%, preferably 5.
5-11.5%, BaO 1-15%, preferably 5.
It is 5 to 12%. MgO, CaO, SrO or BaO
If the content of each of these is more than 15%, the devitrification temperature becomes high, and it becomes difficult to form glass into fibers, which is not preferable. Further, when the content of each of CaO and BaO is less than 1%,
It is not preferable because the meltability becomes poor, the viscosity of the glass becomes high, and it becomes difficult to fiberize the glass.

ZrO ₂ is a component which improves alkali resistance and mechanical strength of glass. This content is 0.1
It is -10%, preferably 0.5-6.5%. ZrO
_If the content of ₂ is less than 0.1%, the alkali resistance and mechanical strength of the glass cannot be obtained, and if it is more than 10%, the devitrification temperature becomes high, and it becomes difficult to fiberize the glass. Therefore, it is not preferable.

TiO ₂ is a component which improves acid resistance, alkali resistance and mechanical strength of glass. This content is 0.5 to 20%, preferably 6.5 to 11.5%. When the content of TiO ₂ is less than 0.5%,
The acid resistance, alkali resistance and mechanical strength of the glass cannot be obtained, and if the content is more than 20%, the devitrification temperature becomes high, and it becomes difficult to fiberize the glass, which is not preferable.

Al ₂ O ₃ is a component that stabilizes the glass and suppresses devitrification, and the content thereof is 0.1 to 10 mol%, preferably 0.2 to 7.5 mol%. When it is less than 0.1 mol%, devitrification is likely to occur, and when it is more than 10 mol%, alkali resistance is deteriorated, which is not preferable.

The total amount of Nb ₂ O ₅ and La ₂ O ₃ is 0 to
It is 1%, and it is preferable that Nb ₂ O ₅ and La ₂ O ₃ are not substantially contained. If the total amount of these exceeds 1%, the manufacturing cost of the glass increases, the glass becomes brittle, and the tensile strength decreases, which is not preferable.

Ratio of BaO to CaO, BaO / C
aO is a molar ratio of 0.3 to 1.6, preferably 0.75.
˜1.45. If the molar ratio of BaO / CaO is smaller than 0.3 or larger than 1.6, the devitrification temperature of the glass becomes high, and it becomes difficult to fiberize the glass, which is not preferable.

Ratio of SrO to CaO, SrO / C
aO is a molar ratio of 0.3 to 2.0, preferably 0.55.
Is about 2.0. If the molar ratio of SrO / CaO is smaller than 0.3 or larger than 2.0, the devitrification temperature of the glass becomes high, and it becomes difficult to make the glass into fibers, which is not preferable.

Ratio of MgO to CaO, MgO / C
aO is a molar ratio of 0 to 2.0, preferably 0.3 to 1.
It is 6. If the molar ratio of SrO / CaO is more than 2.0, the devitrification temperature of the glass becomes high, and it becomes difficult to make the glass into fibers, which is not preferable.

The thermosetting resin used in the present invention is not particularly limited, but epoxy resin, unsaturated polyester resin and vinyl ester resin are suitable in view of moldability and material cost, and vinyl ester resin is particularly preferable. ,
It is preferable because it has excellent alkali resistance and is not easily deteriorated by the alkaline substance in the cement. The glass fiber content with respect to the thermosetting resin is preferably 30 to 70% by volume. That is, when the glass fiber content is less than 10% by volume, the reinforcing effect of the glass fiber cannot be sufficiently obtained, while
This is because if it is more than 70% by volume, the impregnating property of the resin is deteriorated and the productivity is lowered.

As a method of manufacturing the FRP rod for replacing the reinforcing bar of the present invention, a plurality of glass rovings are introduced into a resin tank to impregnate the resin, and then the glass roving is drawn into a cylindrical hardening mold to obtain a rod-shaped molded product. The pultrusion molding thus obtained is preferable because it enables continuous production and has high productivity.

[0046]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the FRP rod of the present invention will be described in detail based on Examples.

Tables 1 to 4 show examples of the present invention (Sample No. 1).
~ 20), and Table 5 shows comparative examples (Sample Nos. 21 and 22).
Indicates. By the way, the sample No. 21 is E glass fiber, N
o. 22 is FRP using AR glass fiber as a reinforcing material
It shows a rod.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

[0051]

[Table 4]

[0052]

[Table 5]

Each sample was prepared as follows.

First, a long glass fiber (diameter 16 μm) having each composition shown in the table was spun, and 2000 filaments were bundled to prepare a DWR (direct wound roving). Then, 24 DWRs were bundled and a vinyl ester resin (RIPOXY R802 manufactured by Showa High Polymer Co., Ltd.) was used as a matrix resin to have a diameter of 5 mm.
Of the FRP rod was pultruded. The glass fiber content of this FRP rod was 50% by volume.

The amount of alkali elution and the mass reduction rate of the glass after the immersion in the alkaline solution were determined based on the method described above.

The initial mechanical strength of the FRP rod is JI
According to SK 6911, a three-point bending test was performed with a span of 50 mm and a crosshead speed of 0.5 mm / min.
evaluated.

The tensile strength retention of the glass fiber was evaluated by immersing the glass fiber in an alkaline solution and measuring the tensile strength before and after the immersion. That is, the tensile strength retention rate was 1% with a 10 mass% NaOH solution at 80 ° C. for a glass strand having a fiber diameter of 13.5 μm and 400 filaments.
The tensile strength before and after the treatment for 6 hours is JIS R 3420.
It was obtained by measuring based on the tensile strength measuring method of the glass yarn described in.

Regarding the damage of the FRP rod, first,
Cut a FRP rod to a length of 550 mm, tie both ends with a cotton thread, and prepare a sample that is curved in an arch shape (semicircular shape) so that the distance between both ends of the rod is 400 mm. Over 60 mm at 60 ° C, 1N
It was evaluated by immersing it in a (normal) sodium hydroxide (NaOH) solution and measuring the time until the sample was broken (broken).

As can be seen from Tables 1-4, Examples 1-2
0, ZrO ₂ and NbO _5/2 in the glass or ZrO,
_Since it contains a large amount of ₂ and TiO ₂ , the mass reduction rate of the glass after immersion in an alkaline solution is low, the alkali resistance of the glass fiber itself is excellent, and the FRP rod is immersed in a 1N sodium hydroxide solution at 60 ° C for 700 hours. It does not break even when immersed, and since the content of alkali metal oxides in the glass is low or does not contain alkali metal oxides,
Alkali metal ions were little eluted or alkali metal ions were not eluted, and the initial mechanical strength of the FRP rod was high.

On the other hand, as can be seen from Table 5, in Comparative Example 21 using E glass fiber, since alkali metal oxide was not contained in the glass, alkali metal ions did not elute, and the initial FRP rod Although it has high mechanical strength, it does not contain ZrO ₂ or NbO _5/2 in the glass, or contains only a small amount of TiO ₂ , so the mass reduction rate of the glass after immersion in an alkaline solution is high and the glass fiber itself has a high resistance. Poor alkalinity, use FRP rod at 60 ℃, 1N
When it was soaked in the sodium hydroxide solution of, it broke in 160 hours.

Comparative Example 2 using AR glass fiber
No. ₂ contains a large amount of ZrO ₂ in the glass, so the mass reduction rate of the glass after immersion in an alkaline solution is low, the alkali resistance of the glass fiber itself is excellent, and the FRP rod is
Although it was not damaged even if it was immersed in a 1N sodium hydroxide solution at 700C for 700 hours, it contained a large amount of alkali metal oxides in the glass, so the amount of alkali elution was large and FR
The initial mechanical strength of the P rod was low.

[0062]

INDUSTRIAL APPLICABILITY As described above, the FRP for reinforcing bar substitution of the present invention
The rod is made of glass fiber that has little alkali metal elution and excellent alkali resistance.
Since the initial mechanical strength of the rod is high and the mechanical strength of the FRP rod does not easily decrease even when an alkaline substance penetrates into the matrix resin, it is suitable as a substitute material for reinforcing bars used for reinforcing concrete.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C04B 14/44 C04B 14/44 Z 16/04 16/04 C08J 5/24 CEZ C08J 5/24 CEZ // C08L 101: 00 C08L 101: 00 (72) Inventor Shinji Nishibori 2-7-1, Harerashi, Otsu-shi, Shiga Nihon Denki Glass Co., Ltd. (72) Inventor Toshikatsu Tanaka 2-7-1 Harashirashi, Otsu, Shiga No. F-term in Nippon Denki Glass Co., Ltd. (reference) 4F072 AA04 AA07 AB09 AB22 AD08 AD24 AD38 AG03 AG13 AK17 AL17 4G062 AA05 BB01 BB03 CC10 DA05 DA06 DB01 DC01 DD01 DE01 DF01 EA01 EA02 EC02 EC01 EC02 EB02 EC01 EB02 EC03 EB02 EC02 EB02 EC03 EB02 EC02 EB02 EC02 EB02 EC02 EB03 EB03 ED02 ED03 ED04 ED05 EE01 EE02 EE03 EE04 EE05 EF01 EF02 EF03 EF04 EF05 EG01 EG02 EG03 EG04 EG05 FA01 FB01 FB02 FB03 FB04 FC01 FC02 FC03 FD01 FE01 FF01 FG03 FG04 FH01 FJ01 FK01 FL01 GA01 GA10 GB01 GC01 GD01 GE01 HH01 HH03 HH05 HH07 HH09 HH11 HH13 HH15 HH17 HH20 JJ01 JJ03 JJ05 JJ07 JJ10 KK01 KK03 KK05 KK07 KK10 MM01 MM16 NN32 NN33 NN34NN34NN34

Claims (10)

[Claims] 1. A glass mass reduction rate when glass powder having a particle diameter of 300 to 425 μm is immersed in a 10 mass% sodium hydroxide aqueous solution and treated at 80 ° C. for 16 hours, the mass reduction ratio of glass is 1.0 mass%. The following is JIS R 3502
An FRP rod for replacing a reinforcing bar, comprising a glass fiber made of glass having an alkali elution amount of 0.10 mg or less measured according to 1. as a reinforcing material. 2. The glass fiber comprises ZrO _{2 in} mole percentage.
The FRP rod for reinforcing bar replacement according to claim 1, which is made of glass containing ₂ to 15% of + NbO _{5/2 and 0} to 15% of Li ₂ O + Na ₂ O + K ₂ O. 3. The glass fiber comprises ZrO _{2 in} mole percentage.
+ TiO ₂ is 3 to 25%, Li ₂ O + Na ₂ O + K ₂ O is 0
The FRP rod for replacing a reinforcing bar according to claim 1, wherein the FRP rod is made of glass containing -15%. 4. The glass fiber comprises SiO _{2 in} mole percentage.
_{40~65%, Li 2 O + Na} 2 O + K 2 O 0~15
%, MgO + CaO + SrO + BaO 20-45%,
ZrO ₂ 0-8%, NbO _5/2 2-12%, TiO ₂
FR for reinforcing bar replacement according to any one of claims 1 to 3, characterized in that it is made of glass having a composition of 3 to 20%.
P rod. 5. The glass fiber comprises, in mole percentage, SiO _{2
46~60%, Li 2 O + Na} 2 O + K 2 O 0~10
%, MgO + CaO + SrO + BaO 25-40%,
ZrO ₂ 0-5%, NbO _5/2 2-10%, TiO ₂
It consists of glass which has a composition of 5-15%, FR for reinforcing bar substitution in any one of Claims 1-4 characterized by the above-mentioned.
P rod. 6. The glass fiber comprises SiO _{2 in} mole percentage.
_{46~70%, Li 2 O + Na} 2 O + K 2 O 0~15
%, MgO 0-18%, CaO 0-18%, SrO
0-10%, BaO 0-15%, ZnO 0-10
%, MgO + CaO + SrO + BaO + ZnO 11 to 11
A glass having a composition of 35%, ZrO _{2 2 to} 15%, and TiO ₂ 5 to 18%.
FRP rod for reinforcing bar replacement according to any one of 3 to 3. 7. The glass fiber comprises SiO _{2 in} mole percentage.
_{46~65%, Li 2 O + Na} 2 O + K 2 O 2~10
%, MgO 0-10%, CaO 0-10%, SrO
0-8%, BaO 5-12%, ZnO 0-5%,
MgO + CaO + SrO + BaO + ZnO 12-30
%, ZrO ₂ 3 to 12%, TiO ₂ 5 to 15%, and a glass having a composition.
The FRP rod for reinforcing bar replacement according to 3 or 6. 8. The glass fiber comprises SiO _{2 in} mole percentage.
_{50~60%, Li 2 O + Na} 2 O + K 2 O 0~1
%, MgO + CaO + SrO + BaO 20-45%,
ZrO ₂ 0.1-10%, TiO ₂ 0.5-20%,
The FRP rod for replacing a reinforcing bar according to claim 1 or 3, wherein Al ₂ O _{3 is} 0.1 to 10% and BaO / CaO is a glass having a composition of 0.3 to 1.6 in a molar ratio. . 9. The glass fiber comprises SiO 2 in mole percentage.₂
  50-60%, Li₂O + Na₂O + K₂O 0 to 0.
5%, MgO + CaO + SrO + BaO 23-40
%, ZrO₂  0.5-6.5%, TiO₂  6.5-1
1.5%, Al ₂O₃  0.2-7.5%, BaO / Ca
A glass having a composition of O in a molar ratio of 0.75 to 1.45.
9. The method according to claim 1, 3 or 8, characterized in that
FRP rod for reinforcing bar replacement. 10. The glass fiber comprises MgO in mole percentage.
0-15%, CaO 1-15%, SrO 0-15
%, BaO 1 to 15%, and a glass fiber containing 1 to 15% of BaO.