JPH02200945A - Fiber reinforcing resin alternate material for reinforcing bar and its manufacture - Google Patents

Abstract

PURPOSE:To improve the strength of reinforcement by forming a sectional outside shape out of straight lines and curved lines and manufacturing a fiber reinforcing resin alternate material for reinforcing bar of closed shape where a straight portion is faced outwards or spiral shape out of winding form using a mandrel. CONSTITUTION:A winding groove 5 consisting of a straight portion 7 and a curved portion 8 is formed at a split mandrel 4. A resin impregnated fiber bundle is wound around the groove 5, and after heating and hardening, it is removed from the mandrel 4 to install a fiber reinforcing resin alternate material for reinforcing bar. A alkali resisting protective layer and as necessary a adhesion reinforced layer to concrete are installed on a surface. At this time, the outside of the wound fiber bundle becomes flat of itself. When the groove 5 is taken at regular intervals, on the other hand, it becomes a closed reinforcement 1 and when provided continuously, it becomes a spiral reinforcement. It is thus possible to make the peripheral length larger than a circular section to increase the adhesive power to concrete, preventing the decrease in the strength of a bent portion.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a fiber-reinforced resin reinforcing bar substitute material to be buried in concrete formwork for forming concrete buildings, concrete Toshin, etc., and a method for manufacturing the same. It is.

[Problems to be solved by conventional technology and invention]

Conventionally, various fiber-reinforced resin reinforcing bar substitute materials have already been proposed to be used in place of reinforcing bars.

When forming a closing reinforcement or a spiral reinforcement using such a bar-shaped fiber-reinforced resin reinforcing bar substitute material, the bar-shaped fiber-reinforced resin reinforcing bar substitute material must necessarily be bent.

However, when bending a fiber-reinforced resin reinforcing bar substitute material, strain is applied in the direction of the fibers at the bent portion.
There was a drawback that the strength of the angular portion was reduced.

Therefore, the applicant has filed Japanese Patent Application No. 63-28888 for a bending method that does not cause a decrease in the strength of rod-shaped fiber-reinforced resin reinforcing bars, but the applicant has proposed a bending method from a different perspective. The present invention was completed as a result of extensive research into whether it was possible to create closing bars or spiral bars using unnecessary fiber-reinforced resin reinforcing bars.

[Means to solve the problem]

Attached drawing? The present invention will be described in detail as follows.

The cross-sectional shape of the rod of the resin material is composed of a curved line and a straight line 1r:t, < is a curved line that is close to a straight line. The flat part 7 of a straight line or a curve close to a straight line is positioned outward.
This relates to a substitute material for reinforcing bars made of fiber-reinforced resin.

A winding groove 5 having a desired cross-sectional shape regulated by curves and straight lines is formed on the mandrel 4 for punching the split mold structure, a resin-reinforced fiber is wound around the winding groove 5, and the resin-reinforced fiber is solidified. A fiber-reinforced resin reinforcing bar substitute material characterized in that a fiber-reinforced resin reinforcing bar substitute material having a closed shape or a spiral shape is produced by removing the rear mandrel 4 and having a cross-sectional shape composed of a curved line and a straight line. This relates to the manufacturing method.

[Function] A winding groove 5 having a desired shape regulated by curves and straight lines is formed on the mandrel 4 having a split structure, a fiber bundle impregnated with resin is wound around this winding groove 5, and the fiber bundle is impregnated with resin. After the fiber bundle is solidified, the mandrel 4 is divided, the divided bodies are removed, and the mandrel 4 is extracted. A fiber-reinforced resin reinforcing bar substitute material having a closed or spiral cross-sectional shape can be obtained.

At this time, since the fiber bundle is wound around the winding groove 5 of the mandrel 4 rotating at high speed, the outermost side of the wound fiber bundle becomes almost a flat surface.

If the winding grooves 5 are not continuous but are provided at regular intervals, @concave grooves 5
The number of obturator muscles 1 can be obtained simultaneously, and the winding groove 5 can be obtained simultaneously.
A spiral reinforcement 2 is obtained by arranging 4 pieces of each in a spiral shape.

The closing reinforcement 1 or the spiral reinforcement 2 thus obtained is used as a reinforcing reinforcement for concrete finishing.

〔Example〕

FIG. 10 shows a mandrel 4 for forming the obturator muscle 1 having the cross-sectional shape shown in FIG. 3, and FIG. 11 is a front view of the mandrel 4.

It is desirable that the cross-sectional shape of winding #5 be selected such that the entrance portion of the winding groove 5 is widest so as not to hinder winding of the resin-reinforced fibers around the mandrel 4.

In the figure, 4'a is the core, 4°b, 4°c, 4'd, 4''e, 4
°r.

4'g, 4'h, 4'i are divided bodies of the mandrel 4, and the resin-reinforced fibers are wound 71I1 on the mandrel 4.
After wrapping around 5, remove 4゛a, then 4゛b,
Remove 4°C14゛d, 4°e, and finally 4'f,
4'g, 4'h.

4゛i is moved inward and removed to remove the mandrel 4.

It is preferable that the dividing body be made of Teflon material or metal treated with a female mold.

In addition, FIG. 8 shows a spiral 117 having the cross-sectional shape shown in FIG.
This is a mandrel 4 for forming i2, and FIG. 9 is a front view of the mandrel 4.

The demolding procedure in this case is the same as above, first pull out the core 4°a, then move the divided bodies 4"b, 4°c, and 4"d inward and remove them, and finally remove the divided body 4"e. , 4゛f,
4"g and remove the mandrel 4.

Next, a specific manufacturing method of the present invention will be described.

A bundle of glass fiber or carbon fiber impregnated with a thermosetting resin such as vinyl ester resin or epoxy resin is wound around the winding 1115 of the mandrel 4 shown in FIG. 8.10.

This employs a general filament winding method as a resin forming method.

After that, the mandrel 4 is removed from the mold after being heated and cured.

In order to impart alkali resistance to the obtained closed-shaped or spiral-shaped FRP material, a protective layer 3 is formed by coating the outer surface with a resin similar to the resin described above.

This coating may be applied by any method such as dabbing, spraying, or powder coating.

If you want to improve the adhesion to concrete, as shown in Figure 7, apply an adhesive such as epoxy resin to form the adhesive layer 6, and then apply alumina abrasive material (for example, Morundum) or the like. abrasive grains 9 are attached to the surface.

Fig. 3 shows a case where a flat part 7 is provided outwardly and the flat part 7 is provided with a draft angle at an opposing position, and the other part is formed into a curved part 8. It's almost a straight line!
l! This is a case where a flat part 7 made of iA is provided as a draft at a position 4 degrees opposite to the flat part 7, and the other part is formed into a curved part 8.

Moreover, FIGS. 5 and 6 illustrate a case in which the outer, inner, and lateral sides are flat portions 7, and the connecting portions between the outer, inner, and lateral sides are curved portions 8. Various other shapes can be designed.

Note that the resin used in the present invention is not limited to thermosetting resins, and thermoplastic resins such as polypropylene resins and nylon resins can be used.

In the figure, reference numeral 10 is a rod-shaped muscle, and reference numeral 11 is a bridge.

〔Effect of the invention〕

Since the present invention is made as described above, it exhibits the following features.

(1) Since the present invention has a structure in which the cross-sectional shape is restricted by straight lines and curves, when comparing the same cross-sectional area, the circumferential length is longer than that of a conventional bar having a circular cross-section.

Therefore, the adhesion force with concrete increases accordingly.

2. Since the product of the present invention is a closing muscle or a spiral muscle made of a bar whose cross-sectional shape is composed of straight lines and curved lines, for example, when used so that the flat part is connected, it will result in so-called surface contact. , the bond becomes stronger.

3. Generally, it is desirable that the reinforcing bars be placed close to the inner surface of the concrete form and maintained at a predetermined distance, and usually a minimum distance between the inner surface of the form and the reinforcing bars is specified.

The product of the present invention is a closing muscle or a spiral muscle made of a bar constituted by a straight line surface and a mountain line surface, and the flat part of the straight line or a curve close to a straight line is located outward, so that the flat part is Compared to conventional closing bars or spiral bars made of bars with a circular cross section, the present invention makes it easier to set the minimum distance. Unlike previous methods, the method involves winding a bundle of resin-reinforced fibers around a mandrel and forming the material instead of bending and molding a bar-shaped fiber-reinforced resin reinforcing bar substitute material. This is an excellent method for producing a fiber-reinforced resin reinforcing bar substitute material, since it is possible to mass-produce bars or spiral bars, and the obtained fiber-reinforced resin reinforcing bar substitute material does not suffer from a partial decrease in strength.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a perspective view of the obturator muscle according to the present invention, FIG. 2 is a perspective view of the spiral muscle according to the present invention, and FIG. 3 is a perspective view of the present invention product. 4.5.6 is a cross-sectional view of another example of the obturator muscle or spiral muscle according to the present invention, and FIG. 7 is another example of the obturator muscle according to the present invention. , FIG. 8 is a front view of the mandrel for manufacturing spiral muscle according to the present invention, FIG. 9 is a front view of the mandrel, FIG. 1θ is a mandrel for manufacturing obturator muscle according to the present invention, and FIG. 11 is a front view of the mandrel 12 are explanatory diagrams showing the state of use of the obturator muscle according to the present invention. l... Obturator muscle, 2... Spiral muscle, 4... Mandrel, 5... Winding groove, 7... Flat part. January 1999

Claims (1)

[Scope of Claims] 1. The cross-sectional shape of a bar of a closed-shaped or spiral-shaped fiber-reinforced resin material used as a closed muscle or a spiral muscle is restricted to a shape consisting of a curve and a straight line or a curve close to a straight line, A fiber-reinforced resin reinforcing bar substitute material characterized in that the flat part of a straight line or a curve close to a straight line is located outward. 2. A winding groove having a desired cross-sectional shape regulated by curves and straight lines is formed on a mandrel having a split structure, a resin-reinforced fiber is wound around this winding groove, and after the resin-reinforced fiber has solidified, the mandrel is removed. 1. A method for manufacturing a fiber-reinforced resin reinforcing bar substitute material, which comprises producing a fiber-reinforced resin reinforcing bar substitute material having a closed shape or a spiral shape and having a cross-sectional shape composed of a curved line and a straight line.