JPH06157108A - Carbon fiber reinforced lightweight mortar containing frp powder - Google Patents

Abstract

PURPOSE:To provide lightweight mortar excellent in mechanical strength and having high freezing-thawing resistance by utilizing FRP (fiber reinforced plastic) scraps as part of fine aggregate and carrying out reinforcement with carbon fibers. CONSTITUTION:Short carbon fibers are random dispersed in lightweight mortar contg. powder of FRP scraps as part of fine aggregate to obtain the objective carbon fiber reinforced lightweight mortar contg. FRP powder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention of this application relates to a lightweight mortar used as an exterior material of a building or a raw material of an outer wall material of a building.

[0002]

2. Description of the Related Art Conventionally, lightweight fine aggregate such as shirasu balloon or perlite is used for mortar, depending on the application.
There were lightweight mortars with many bubbles introduced into the mortar, and fiber reinforced mortars containing alkali-resistant glass fibers in the mortar. However, those mortars have many mechanical strengths such as low mechanical strength even if weight reduction is realized, difficult weight reduction even if strength is obtained, or extremely weak against freeze-thaw. It had drawbacks. On the other hand, FRP (fiber reinforced plastic) reinforced with a reinforcing material such as glass fiber
Has excellent properties as a molding material and is used in many fields, but its high strength and high durability make it difficult to crush and disassemble the waste of FRP that is no longer needed. Accordingly, if left unattended, it causes environmental damage, which is a social problem. On the other hand, the inventor of the present application succeeded in finely pulverizing FRP waste as a result of earnest research, and recently, 100 kg of FRP fine powder having an average particle diameter of several μm per hour was obtained. We have succeeded in developing a crusher that can be manufactured. (Japanese Patent Application No. 3-126957) Further, as a result of studying the use of the FRP fine powder as an aggregate of a cement-based material, it was found that it was extremely useful as a fine aggregate of concrete or mortar.

[0003]

DISCLOSURE OF THE INVENTION The invention of the present application provides a lightweight mortar excellent in mechanical strength, cracking due to drying, and freeze-thaw resistance, and uses FRP fine powder as a fine aggregate of the mortar. However, it also aims to recycle the FRP waste materials that are produced in large quantities as industrial waste.

[0004]

[Means for Solving the Problems] The carbon fiber reinforced lightweight mortar containing the FRP powder of the present application has short carbon fibers randomly dispersed in the lightweight mortar containing the powder of FRP waste as a part of the fine aggregate. It was made.

[0005]

[Function] The powder of FRP waste material mixed as a part of the fine aggregate has a small particle size, so that it reduces the voids in the mortar, suppresses the occurrence of cracks when the mortar is dried, and freezes and thaws it. In contrast, the reduction of voids and the water repellency of the powder of the FRP waste material prevent the entry of water into the mortar, prevent the freezing phenomenon, and improve the freeze-thaw resistance. Also, the short carbon fibers randomly dispersed throughout the mortar significantly improve the bending strength and compressive strength after hardening of the mortar by the mechanical properties of the carbon fiber itself without changing the unit volume weight of the mortar.

[0006]

EXAMPLES Examples of the invention of this application will be described.
For the purpose of improving the properties of the lightweight mortar, a carbon fiber reinforced lightweight mortar was prepared by randomly dispersing a relatively small amount of short carbon fibers in a lightweight mortar in which FRP waste powder was mixed as a part of fine aggregate. Carbon fiber is 6 mm long
A general-purpose pitch-based product, a cement was ordinary Portland cement, a lightweight fine aggregate was Shirasu balloon, and an FRP waste powder containing 75% or more of particles having a particle size of several μm. Further, a high performance water reducing agent (Mighty FD), methyl cellulose and silica fume were used as admixtures. In order to investigate various characteristics as a lightweight mortar,
A test piece was made and tested. Specimen (lightweight mortar)
Has a water-cement ratio of 0.9, a fine aggregate (shirasu balloon and FRP waste powder) cement ratio of 0.67, a FRP waste powder fine aggregate ratio of 0.43, and a high-performance water-reducing agent with a cement weight of 1 It was made by adding 0.5%. At that time, in the case of Specimen A, 0.5% by weight of water of methyl cellulose was added.
Further, in the case of Specimen B, 20% of the cement weight was replaced with silica fume. The volume mixing ratio (Vf) of carbon fiber was set to 1.5% for both test pieces A and B. Further, for the purpose of comparison of characteristics, a test sample was also prepared in which each of the test samples A and B did not contain any carbon fiber (Vf = 0%). The kneading was performed using a normal mortar mixer. The size of the test piece is 40 mm in width and height and 16 in length.
The thickness was set to 0 mm, and it was manufactured according to JIS R5201, and was cured in water for 7 days. The flow value, unit volume weight, bending strength, and compressive strength were obtained for each of the prepared specimens. The results are shown in Table 1.

[0007]

[Table 1]

The dispersibility of the carbon fibers was good in both specimens A and B. Further, the unit volume weight was almost the same as when the fiber was not mixed even when the fiber was mixed. However, the fluidity of the composite material was naturally lower than that of the composite material not reinforced with carbon fiber. In the case of Specimen A using methyl cellulose, the bending strength was twice as high and the compressive strength was 1.8 times as high as that of the one not reinforced with carbon fiber. Also, in the case of the sample B using silica fume, the bending strength and the compressive strength were 2.4 times and 1.2 times, respectively, as compared with those not reinforced with carbon fiber. These load-deflection curves are shown in FIG. In FIG. 1, 1 is a carbon fiber reinforced sample A with Vf = 1.5%, and 2 is Vf =
Specimen B reinforced with carbon fiber of 1.5%, 3 shows load-deflection curves of specimens A and B with Vf = 0% not reinforced with carbon fiber. As shown in the figure, the amount of deflection up to the maximum load was about four times higher than that of one not reinforced with carbon fiber in any of the specimens. Thus, it was possible to improve the strength and the deformation performance while maintaining the light weight even with a relatively small amount of fibers.

[0009]

EFFECT OF THE INVENTION The carbon fiber reinforced lightweight mortar of the present invention is superior to conventional lightweight mortar in terms of lightness, mechanical strength such as bending strength and compression strength, crack resistance during drying and freeze-thaw resistance. It is extremely useful from the viewpoint of exhibiting remarkably excellent characteristics and reusing waste FRP waste material as a resource.

[Brief description of drawings]

FIG. 1 is a load-deflection curve diagram when measuring a bending strength of a test piece in an example.

[Explanation of symbols]

1 Load-deflection curve of specimen A (Vf = 1.5%) reinforced with carbon fiber 2 Load-deflection curve of specimen B (Vf = 1.5%) reinforced with carbon fiber 3 Not reinforced with carbon fiber Specimens A and B (Vf = 0%)
Load-deflection curve

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location C04B 14:38 A 2102-4G 14:16 2102-4G 24:22 B 2102-4G 24:38 D 2102-4G 22:06) A 2102-4G (72) Inventor Toshihiko Asada 1-34-19 Higashiizumi, Komae City, Tokyo

Claims (1)

[Claims] 1. A carbon fiber reinforced lightweight mortar containing FRP powder, wherein short carbon fibers are randomly dispersed in a lightweight mortar containing powder of FRP waste as a part of fine aggregate.