JPH02258657A - Reinforcing material for hydraulic substance - Google Patents

Abstract

PURPOSE:To improve the workability, applicability and reinforcing performance to a hydraulic substance by collecting and fixing a specific synthetic fiber with a thermosetting resin into a rod and knitting or weaving the rods in a lattice form. CONSTITUTION:A PVA synthetic fiber or a wholly aromatic polyester synthetic fiber having a polymerization degree of 1,000-20,000, a saponification degree of >=98mol%, a fineness of 0.5-20dr, a tensile strength of >=15g/dr and a Young's modulus of >=300g/dr is collected and twisted at a twist of 50-200 turns/m to form a tow of 20,000-2,000,000dr. The tow is fixed by impregnating with a thermosetting resin to obtain a rod having a resin content of >=60vol.%. The rods are knit or woven at a warp or weft distance of 2-20cm and the cross points of the rods are fixed with a resin such as unsaturated polyester resin or olefin resin.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a planar reinforcing bar for civil engineering and construction, which is used as a reinforcing material for hydraulic materials such as cement mortar and concrete.

<Prior Art and Problems to be Solved by the Invention> Reinforcing bars have traditionally been used as structural materials in civil engineering work, construction work, or building components, and their performance has been determined by JIS G.
3112.3117.

Reinforcing bars are susceptible to: - Internal battery formation, rusting due to rainwater and salt, -
Electric conductivity, ■ Magnetism or weak magnetism, ■ Heavy (the reinforcing bar itself has a large specific gravity, and furthermore, it requires a certain cover thickness, which makes the member thick and heavy. However, on the other hand, ■ High tensile strength and Young's modulus; ■ Same linear expansion coefficient as concrete; ■ Low creep; ■ Excellent workability by bending and welding; ■ Mass-produced and available anywhere; ■ Excellent economic efficiency. It has its advantages.

From a construction perspective, when using reinforcing bars, a certain cover thickness is required, so it is necessary to assemble the reinforcing bars to position them.Furthermore, in planar construction, reinforcing bars are hard wires and cannot be easily woven, so reinforcing bars are placed in a lattice pattern. There is a problem in that it takes a lot of time and effort to prepare the particles, resulting in poor productivity. Furthermore, after reinforcing bars are placed in mortar and molded, the reinforcing bars must be cut when cutting the molded product, which leaves problems with the cutting method.

Regarding reinforcing grids that do not have such problems, see "Reinforced Plastics J Vol. 34, No.

Reviewed on pages 6.9-17. The lattice-shaped reinforcing material introduced there is molded into a lattice shape using glass fiber and resin, and this material is currently commercially available.

However, since this product uses glass 1M1ffl, there are still problems with its alkali resistance in cement, and the amount of molding resin is large, so there is also the problem of adhesion to the hardened cement.

Therefore, as a result of conducting research on technology to eliminate the drawbacks of reinforcing bars and glass*i, we have developed a method that takes advantage of the characteristics of rod-shaped objects made of specific fibers, mechanical performance, and stiffness. It was discovered that a lattice-shaped reinforcing material having excellent workability, construction properties, and reinforcing performance against hydraulic materials could be obtained by weaving the material into a lattice-like shape, and the present invention was achieved based on this finding.

Means for Solving the Problems> The present invention provides polyvinyl alcohol (hereinafter abbreviated as PVA) synthetic fibers or fully aromatic fibers having a tensile strength of 15 g/dr (dr is an abbreviation for denier) or more and a Young's modulus of 300 g/dr or more. It is made of polyester (hereinafter abbreviated as PA) synthetic fibers and a thermosetting resin that bundles and fixes these fibers, and is woven into a rod-like or lattice-like structure in which the fibers account for 60% by volume or more, and A reinforcing material of a hydraulic material fixed at the intersections thereof, preferably having a circular, square, or rectangular cross section, and having irregularly shaped protrusions on its surface. It is.

The features of the present invention are: ■ It is a synthetic fiber with high strength and high Young's modulus; ■ The synthetic fiber is alkali resistant; ■
Non-magnetic; ■No conductivity; ■Has a coefficient of linear expansion that is almost the same as that of hydraulic materials; ■Less creep under load; ■Fibers that are sufficient to propagate the stress applied to the rod-shaped object to the fibers. ■ Has excellent structural adhesion between sticks and hydraulic substances such as cement, and ■ Can be used at very shallow depths from the surface without requiring a predetermined cover thickness from cement, etc. The reinforcement effect can be applied not only in one direction but in two directions because the rods are woven in a lattice pattern. ■Because the reinforcement is already woven in a lattice-like plane at the factory. It is lightweight and extremely easy to transport and handle, and since the synthetic fiber is made of resin, it can be easily cut with a saw or pliers.
Concrete members used as reinforcing bars can be easily cut with the same cutter, and ■It is highly economical. As described above, it can be used as a lattice-like reinforcing material for hydraulic materials, which is excellent not only in terms of reinforcing performance but also in terms of workability, workability, safety, and economic efficiency.

First, the rod-shaped object used in the present invention has a tensile strength of 15 g.
/dr or more and a Young's modulus of 300 g/dr or more, PVA-based synthetic fibers or FA-based synthetic fibers are composed of 60% by volume or more and a thermosetting resin, and are obtained by a pultrusion method.

The PVA-based synthetic fiber used has a polymerization degree of 1000 to 20.
000 and uses PVA with a saponification degree of 98 mol% or more, and the tensile strength of the fiber is 15 g/dr or more,
Young's modulus is required to be 300 g/dr or more. Preferably tensile strength 17-30 g/dr, Young's modulus 450-t
It is ooog/dr. Tensile strength and Young's modulus 15
If it is less than g/dr, or less than 300 g/dr, it cannot fully exhibit its performance as a fiber reinforcing material.

The preferred fineness of the constituting PVA-based fibers is 0.5 to 20 deniers, which are suitable conditions for producing fibers with high strength and high Young's modulus, and also by increasing the surface area of the fibers. It is also preferable in order to increase the adhesive strength with the resin. Although a fine denier of less than 0.5 denier is more preferable in terms of surface area, it is not preferable because it lowers the volume percent of the fibers after alignment and resin impregnation during pultrusion.

On the other hand, if it exceeds 20 deniers, it will be difficult to obtain fibers with high strength and high Young's modulus, and reinforcing bars with sufficient strength will not be obtained because the adhesive area with the resin will decrease.

Furthermore, the PA-based synthetic fiber used in the present invention 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; It is a wholly aromatic polyester, which is called wholly aromatic in the sense that at least one aromatic ring of each component contributes to the polymer main chain, and is a so-called thermotropic polyester that can form an anisotropic melt phase. It is a liquid crystalline wholly aromatic polyester.

Among these wholly aromatic polyesters, hydroxybenzoic acid, especially p-hydroxybenzoic acid and 6=hydroxy-
Polyesters with 2-naphthoic acid, and also p,
In addition to polyesters copolymerized with p-bisphenol as the third component, polyesters consisting of p-hydroxybenzoic acid, p, p'-biphenyl, terephthalic acid and/or isophthalic acid are useful, but are limited thereto. However, this does not preclude the introduction of other components into the polymer as long as they do not impede the purpose of the present invention.

Generally, these FA-based synthetic fibers are heated at 290°C in air.
After 4 hours of heat treatment, the strength of the filament is 15g/
dr or more, elongation of 6% or less, and Young's modulus of 400 g/dr or more.

In particular, monomers such as p-hydroxyamino acid, fragrant acid and 6.2-
Shino, which is mainly composed of a copolymer of hydroxynaphthoic acid, has a strength of 20 g/dr or more by the same heat treatment as described above.
The elongation is 4% or less and the Young's modulus is 500 g/dr. This F
For A-based synthetic fibers, a weaving change of 1 to 3,000 deniers is preferable, and this range is a suitable condition for producing fibers with high strength and high Young's modulus.In addition, by increasing the surface area of the fibers, the adhesive strength with the resin is improved. It is preferable to increase the Although a fine denier of less than 1 denier is more preferable from the viewpoint of surface area, there are problems with the spinning conditions, and furthermore, the fiber alignment during pultrusion and the volume percentage of the fiber after resin impregnation are reduced. Undesirable. On the other hand, if it exceeds 3000 denier, it is difficult to obtain fibers with high tenacity and high Young's modulus, and the adhesion area with the resin decreases, making it impossible to obtain sufficient reinforcing bars or tensile material.

A variety of thermosetting resins can be selected, but reinforcing bars used for cement concrete are used in cement alkali, so those that cause the adhesive to deteriorate with alkali or peel off at the adhesive interface with fibers should not be used. Cannot be used @ In addition, thermosetting resins are used because they can fully exert the power as a bundle when fibers are bundled, and among them, polyglycine ether compounds obtained by reacting glycols and polyols with epichlorohydrin. or monoglycyl ether compounds obtained from alcohols and phenols, bisphenol A-based unsaturated polyester resins, and evoquin resins obtained from bisphenol A and epichlorohydrin through a condensation reaction.

These resins have particularly excellent adhesive properties, do not deteriorate in cement alkaline solution, and do not show any decrease in adhesive strength with PVA-based fibers and PA-based fibers.

In addition, vinyl ester resins and bisphenol-based vinyl ester resins, melamine-formalin-based, phenol-based,
Thermosetting resins such as urea-based resins may also be used.

The volume of w & thrust metal contained in the resin must be 60% or more, and the reason is that the strength of the fibers as a reinforcing material can be exerted when the resin as a matrix component is more effective than in composites using continuous fibers. It is clear that the smaller the amount, the higher the tensile strength and Young's modulus of the composite material. In the present invention, if the volume occupied by the fibers in the composite material is not 60% or more, the mechanical properties such as the strength and Young's modulus of the fibers will deteriorate, which is meaningless. In addition, in pultrusion molding, it is preferable to use a large amount of resin in order to suppress air entrapment when the fibers pass through the pultrusion nozzle and to mold the fibers with lubricity. The amount of resin must be 40% or less.

The cross-sectional shape of the rod-shaped article obtained by the pultrusion method is preferably square or rectangular. This is because when g-woven in a lattice shape, the bonding area at the intersections of the lattice increases, making it easier to obtain strength at the intersections, but it may also be circular, flat, etc.

In addition, protrusions may be provided on the surface of this rod-like object, if necessary, in the same way as deformed reinforcing bars, in order to increase the adhesion strength of cement or the like. As a method for imparting protrusions, a yarn having a denier thickness of 1 to 5% of the total fineness at the time of molding the rod-shaped body was used, and twists were applied at 50 to 200 twists per meter to increase the deformability. Twisted yarns made of PVA synthetic fibers, aramid synthetic fibers, and polyarylate synthetic fibers were impregnated with the index finger used during pultrusion molding, and then pultruded into a rod-shaped object at an angle of 40 to 50 degrees with respect to the axial direction. An irregularly shaped rod-shaped body can be obtained by winding two cords so as to form a diagonal seam at an angle, heat-treating the cords, and joining them together. The winding pitch is called the diagonal stitch spacing, and the value obtained by dividing the average spacing of the stitches by the diameter of the bar is preferably 06 to 0.8.
Most preferably it is about 0.7. The total denier of the fibers in the rod-shaped body is 20,000 to 2.800.0
00 denier is common.

The rod-shaped body of the present invention used for constructing a lattice shape can be used as a continuous scroll, or it can be a straight-shaped body cut into a predetermined length. The wire diameter of the rod-like material must be 5+m or less per round diameter in order to make it into a scroll. If the thickness is larger than that, it will be supplied in a straight line.

It is better to bend the warp threads in order to weave rod-shaped objects corresponding to the weft threads into a lattice shape, but if the wire diameter is small, this may be done as necessary.

In order to weave rod-like objects corresponding to wefts, it may be straight or may be bent if necessary.

It is woven in the same manner as plain weave to form a lattice-like object.

The lattice spacing of the lattice-like material is 2 to 20 to allow the slurry of a hydraulic material such as cement mortar to flow well between the lattices.
cm is better. Preferably it is 3 to 15 cm.

The intersection points of the rod-like objects of the woven grid-like object must maintain the grid form. It is necessary to firmly adhere to the cement hardened body in order to maintain adhesive strength. The fixing may be done using a textile, wire, a fixing jig, or the like. In addition, unsaturated polyester resins (vinyl ester type, bisphenol type), which are usually fX-facilitated resins, may be used, and evoquino resins, acrylic resins, urea type resins, phosphoric acid resins, etc. may also be used. can.

Further, hot melt type thermoplastic resins can be used with 1-1, and vinyl resins, olefin resins, acrylic resins, etc. can also be used, as long as they have the performance of an elastomer.

The hydraulically cured material to which the present invention is applied is a general term for inorganic materials that harden by adding water, and representative examples thereof include cement and gypsum.

<Function> The lattice reinforcement material of the present invention has excellent mechanical performance, durability, workability, safety, workability, and economic efficiency as a reinforcing material for cement mortar, concrete, etc. It can be used as a reinforcing member. In particular, it can be used as an on-site construction material for civil engineering and construction, and as a material for factory production.

When used in linear motor cars, etc., it is effective as a non-magnetic, non-conductive reinforcing member, and can be used as a reinforcing member for flat building materials using lightweight concrete.

It also does not rust, has excellent reinforcing performance, and improves impact resistance. Furthermore, since the workability of cutting the member is simple, the workability is also excellent.

This will be explained below using examples.

Example! PVA with a degree of polymerization of 4500 and a degree of saponification of 99.9 mol%
By wet spinning from IS liquid, single fiber fineness of 1,
8 denier, tensile strength 18.5g/dr, elongation 35%
, Young's modulus 460g/dr 1800 denier +000
A filamentous PVA fiber was obtained. The 140-fiber cheese was attached to a creel with a tension control device to reduce the total denier to 25.
The tow was carefully introduced into a rotating date roll so as not to disturb the tow in the impregnating bath with Evokin resin (Epicoat 828, manufactured by Shell Evokin Co., Ltd.).

The adhesion rate of the resin was reduced to 30% by volume, and the volume% of the fibers was 70%. Pultrusion molding nozzle - 5 sides
．． A 3 mm square piece was used. The curing temperature of the resin is 1
Molding was carried out at 80° C. and at a speed of 3 m/min. Furthermore, the drawing roll speed after heat curing was 0.7% higher than that of the date roll. Instron TT is used to measure the tensile strength of rod-shaped objects.
A strainer with a test length of 30 cm was attached to the sample using CM.

Further, the above fibers were bundled to 3,600 deniers and twisted at 120 turns/m, then impregnated with the above resin and wound diagonally at 45° and 135° in the axial direction for 180°.
Heat treatment was performed for 3 minutes in air at ℃ to obtain a rod-shaped object with protrusions on the surface.

Example 2 A molten liquid crystal polymer consisting of a copolymer of p-hydroquine benzoic acid and 6-hydroxy-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 15QO.
A heat treatment system of d/3QOf was obtained. Its single fiber denier is 5 denier, tensile strength is 24.3g/dr, and elongation is 3.4.
%, Young's modulus was 600 g/dr.

The 160-fiber cheese was attached to a creel with a tension control device, and the total denier was adjusted to 240,000 denier, and the cheese was carefully introduced into a rotating date roll so as not to disturb the tow in an epoxy resin (Epicoat 828 manufactured by Oil-based Shell Epoxy Co., Ltd.) impregnation bath. The adhesion rate of the resin was reduced to 30%, and the volume percent of the fibers was 70%. Pultrusion molding nozzle
A square piece with sides of 5.31 was used. The curing temperature of the resin was 180° C., and molding was performed at 3 m/min. Furthermore, the drawing roll after heat curing had a drawing tension that gave a speed difference of 0.7% compared to the date roll.

The tensile strength and other properties of the rod-like material were tested in the same manner as in Example 1, and the results are shown in Table 1. Furthermore, the rod-shaped article was impregnated with the same resin using the same fibers of 3000 denier and twisted at 120 turns/m, and protrusions were formed on the surface in the same manner as in Example 1.

Strength kg/am” 128
165 Young's modulus kg/11116000
8800 Example 3.4 The rods obtained in Example 1.2 were woven in plain weave in a lattice pattern so that the warp and weft were at intervals of 5cI+1.The rods were set with 18 creases pre-prepared for the warp. For the weft threads, one by one, straight, are driven to a length of 180 cm.
Each grid was obtained with a width of 90 cm. The intersections were glued together using epoxy resin that cures at room temperature. Each grid-like object could be easily cut on a stand. The total weight of each is 3300g (
Example 3) and 32[10 g (Example 4), which could be easily transported by hand.

For comparison, a similar method was applied to SD6 deformed reinforcing bars, but the reinforcing bars were hard and a lattice-like object could not be woven.

Examples 5, 6, 7.8 and Comparative Examples 1, 2, 3.4 Examples as reinforcing bars in cement matrix! .

Example 3. A lattice-like object was made using the atypical muscle prepared in 2.
The reinforcing effect was investigated using No. 4. Also, for comparison,
As Comparative Example 1, commercially available SD6 deformed reinforcing bars were welded at intervals of 5 CIm, and the reinforcing effect was investigated at a reinforcing bar arrangement ratio of 0°56%. In addition, comparative example 2.4 was a plain one without reinforcement.

The cement mortar composition used in Example 5.6 and Comparative Example 1.2 was 100 parts crushed early strength cement (Asano early strength cement) (all parts by weight hereinafter), silica sand < FIL silica sand silica sand No. 5) 3
00 parts, gravel (Okayama Asahikawa 51 particle size or less), 150 parts were weighed and dry mixed in an omni mixer for 1 minute, then
52 parts of water and 2.5 parts of a water reducing agent (Kao Mighty 150) were added and mixed for 2 minutes to obtain a mortar.

In fact, the composition of the lightweight cement mortar used in Example 7.8 and Comparative Example 3.4 was early strength cement (Asano early strength cement) 1
00 parts, fine powder pearlite (Ube 1 type) 10 parts, expanding agent (
Add Denka Kagaku Kogyo Co., Ltd. Denka CS A #20) and dry mix for 1 minute using an omni mixer. Add 3 parts of a foaming agent (formix C2 manufactured by Hamano Kogyo Co., Ltd.) and 1 part of a water reducing agent and mix for 2 minutes using an omni mixer. and got mortar. This plain mortar was designated as Comparative Example 4.

For molding, a mold with a thickness of IOX, a length of 40 cm and a width of 40 cm was used.
The soil was placed so that the cover thickness was lc■. For those without reinforcement, the molded frames of the same size were used as they were.

Cement mortar of Example 5.6 and Comparative Example 1.2 and Example 1] The lightweight cement mortar of Example 7.8 and Comparative Example 3.4 was poured and molded.

For curing, Examples 5 and 6 and Comparative Example 1.2 were cured by leaving them at room temperature overnight to harden, then demolding and curing in water for 4 weeks.

Examples 7 and 8 and Comparative Examples 3 and 4 were left at room temperature for a day and night, then demolded, and then left in the air for 4 weeks of curing.

The bending strength was measured using a Shimadzu universal testing machine. The span length was set to 30 cm, and the maximum breaking load and its deflection were measured using the center loading method. The bending strength was determined from (where P is the 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-2.
The following margin Examples 5 and 6 are Comparative Example 1
There is also a reinforcing effect compared to Comparative Example 3, and Examples 7 and 8 also have a reinforcing effect compared to Comparative Example 3.

When Examples 7 and 8 and Comparative Example 3.4 were cut with a rotary galater, Example 7.8 could be easily cut. Compared to this, the one using the reinforcing bars of Comparative Example 3! The blade could no longer sharpen after just cutting it.

Patent applicant RiRashi Co., Ltd.

Claims (1)

[Claims] (1) Tensile strength is 15g/dr or more, Young's modulus is 30
A rod-shaped object consisting of polyvinyl alcohol-based synthetic fiber or fully aromatic polyester-based synthetic fiber of 0 g/dr or more and a thermosetting resin that bundles and fixes the fiber, and in which the proportion of the fiber is 60% by volume or more. A reinforcing material made of a hydraulic material, characterized in that it is knitted in a lattice pattern, and the intersections of the rods are fixed.