JPH0489346A - Concrete reinforcing member and its production - Google Patents

Abstract

PURPOSE:To enhance adhesion and to prevent interlayer separation by coating a core with a fiber-reinforced thermosetting resin and forming ruggedenesses to improve the adhesion to concrete. CONSTITUTION:A reinforcing fiber (e) impregnated with a thermosetting resin is passed through a die 6 to form a semihardened core (a). A reinforcing fiber (f) is provided on the periphery of the core (a) in its longitudinal direction and impregnated with a thermosetting resin 8. A fastening material (g) is wound on the resin 8 impregnated coating layer to form ruggednesses (c) over the surface. The fastening material and the core (a) are then heated, integrated and hardened. Consequently, a two-layer concrete reinforcing material A in which the core (a) is coated with the layer (b) is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a concrete reinforcing member that replaces reinforcing reinforcing bars and PC steel materials buried inside concrete to reinforce concrete, and a method for manufacturing the same.

[Conventional technology]

It has already been proposed to use a rod-shaped body made of fiber-reinforced plastic reinforced with a thermosetting resin with a plurality of longitudinally extending fiber bundles as a concrete reinforcing member in place of reinforcing reinforcing bars that are prone to rust.

For example, Japanese Patent Application Laid-Open No. 61-274036 discloses a reinforcing bar in which a locking portion is formed around the rod-shaped body made of fiber-reinforced plastic.

This locking part is characterized in that a filament or roving fixed with a thermosetting resin is wound around or attached to a rod-shaped body to form a convex part, and the convex part provides adhesive force with the concrete.

[Problem to be solved by the invention]

When the reinforcing bars are embedded in concrete, the locking portions are integrally connected to the concrete, so the tensile force applied to the concrete body is transmitted to the rod-shaped body core via the locking portions.

Furthermore, when the reinforcing bars are used as tension members in a pre-tension system, for example, the locking portions transmit compressive force from the core to the concrete body in order to introduce prestress into the concrete body.

In either case, the structurally large tensile resistance of the core of the reinforcing bar is utilized, but as is clear from the above, the transmission of force between the core and the concrete body is This is done via a locking part.

Therefore, it is desirable that the bonding strength between the core portion and the locking portion be as large as possible.

However, the adhesive strength between the core and the locking part is determined by the bonding area between the filament or roving to be wound and the core, so the bonding strength between the core and the locking part is significantly smaller than the tensile resistance of the core. For this reason, when the reinforcing bar is subjected to a tensile or compressive load, a glabellar peeling phenomenon occurs between the core and the filament or roving of the locking part, and the filament or roving tends to break (for this reason, the conventional With the reinforcing bars, it was not possible to fully utilize the tensile resistance of the core.

The present invention provides a concrete reinforcing member that solves this problem and a method for manufacturing the same.

[Means to solve the problem]

The present invention will now be described in detail with reference to the accompanying drawings.

Reinforcing fibers are arranged in the longitudinal direction around the outer periphery of a rod-shaped core material in which thermosetting resin is reinforced with reinforcing fibers arranged in the longitudinal direction, and the reinforcing fibers are impregnated with thermosetting resin. This invention relates to a concrete reinforcing member characterized in that irregularities are arranged in parallel in the longitudinal direction on the surface of an impregnated coating layer by an appropriate means, and the coating layer and a rod-shaped core material are integrally thermosetted.

2. The concrete reinforcing member according to claim 1, wherein concavities and convexities are provided in parallel in the longitudinal direction on the surface of the coating layer by wrapping a tightening material around the coating layer.

Reinforcing fibers impregnated with thermosetting resin are passed through a die to form an uncured or semi-hardened core material, and reinforcing fibers are arranged longitudinally around the outer periphery of this core material. is impregnated with a thermosetting resin, a tightening material is wound at intervals around the outer periphery of this resin-impregnated coating layer, unevenness is provided in parallel in the longitudinal direction on the surface of the coating layer, and uncured or semi-cured resin is coated with this coating layer. The present invention relates to a method for producing a concrete reinforcing member, which is characterized by heating a rod-shaped core material in a hardened state to thermally harden the material together.

4. The method for producing a concrete reinforcing material according to claim 3, wherein the reinforcing fibers arranged in the longitudinal direction of the outer periphery of the core material are attached to the core material in a state where the tension is loose or in a slack state. It is.

[For production]

In the present invention, a core material and a coating layer having parallel projections and recesses are integrally thermally cured by FRP curing.

The unevenness is formed by winding the tightening material, and large unevenness is formed by adding the reinforcing fibers of the coating layer in a loose or sagging state and wrapping the tightening material around the reinforcing fibers.

In addition, in the present invention, the covering part in which unevenness is formed in the longitudinal direction to have a locking effect on concrete is also made of a hardened thermosetting resin with reinforcing fibers arranged in the longitudinal direction, so it is similar to the core material. It will have a large tensile resistance,
In addition, since both are heat-cured together, the bonding force between the core material and the covering layer is strong, and since the unevenness is arranged in parallel in the longitudinal direction, the concrete body is more stable than conventional reinforcing bars. Higher adhesion strength can be obtained against
As a result, the tensile strength of the reinforcing material can be fully utilized.

〔Example〕

The illustrated embodiment will be described.

In the process diagram shown in Fig. 1, numeral 1 is a creel stand from which a large number of bundled ropings (reinforcing fibers (A)) are fed out, 2 and 2' are guide tension bars, 3 is a core resin tank, and 4 is a guide. Bar 5 is the drawing part, 6 is the heating gun,
7 is a bobbin for winding reinforcing fibers (b) for feeding out the focused roving for forming a coating layer; 8 is a coating resin tank; 9 and 10
1 is a bobbin for unwinding the tightening winding thread (8), 11 and 12 are winding devices, 13 is a heating furnace for curing, and 14 is a take-off device.

The reinforcing fibers (A) impregnated with a thermosetting resin by a conventional method are bundled into a rod shape in the drawing section 5, and the rod-shaped bundle material a° is passed through a heating die 6 or a heating device in place of this to uncured or semi-hardened fibers. A rod-shaped core material a in a hardened state is formed.

When this core material a is passed through the coating resin tank 8, reinforcing fibers (b) are supplied from before the coating resin tank 8 so as to wrap around the outer periphery of the core material a, and the reinforcing fibers (b) are supplied along the core hardening material a into the coating resin tank. 8.

For this purpose, a coating layer sufficiently impregnated with a thermosetting resin is disposed around the outer periphery of the core material a, resulting in a two-layer structure in cross section as shown in FIG.

The device 1 wraps the outer periphery of this two-layered coating layer.
In step 1, for the covering layer, a tightening material thread (c) employing relatively thin yarn or roving is spirally wound while applying tension.

The drawing shows a case in which the winding devices 11 and 12 are installed together and the tightening material thread (8) of the thread material is wound in the opposite direction.

As a result, the outer periphery of the coating layer is narrowed, and unevenness C (projections 15 and depressions 15') is formed in the longitudinal direction.

Rod-shaped molded material A with unevenness C formed in this way
' is introduced into a heating furnace 13, further taken out by a take-up machine 14, cut into a desired length, and the fiber-reinforced covering layer of the present invention having an uneven upper surface is thermally cured integrally with the core material a. A concrete reinforcing member A is obtained.

At this time, the reinforcing fibers of the covering layer are loosened so that the tension approaches zero, and the wrapping is made slack by rotating the device 11 rapidly, and when attached to the core material a, the tightening material thread (
8) Large unevenness C is formed by winding.

The degree of unevenness formed on the coating layer can be adjusted to a desired degree by adjusting the wrapping interval of the tightening material (8) and the intensity of the tension.

In FIG. 6, unevenness is formed in the longitudinal direction of the core material a by wrapping an unevenness generating material 16 in the form of a roving or tape around the outer periphery of the core material a, or by using a sandwich mold to arrange the unevenness side by side.

If a covering layer is disposed around the outer periphery of the core material a, and the tightening material (8) is wound so as to be located between the unevenness-generating materials 16, the unevenness of the covering layer becomes even better.

Furthermore, by arranging reinforcing fibers impregnated with a resin having a high viscosity on the outside of the coating layer, the occurrence of irregularities can be improved.

A net-like tape may be used as the tightening material (c).

The thermosetting resin of the coating part is coated with thixotropic agents and fillers in order to ensure that the uneven shape is maintained during the curing process and to heat-cure the resin together with the core material a with strong adhesive force. or short fibers may be appropriately mixed.

The tightening material (c) may be removed after hardening using a removable material such as a plastic wire without leaving it on the product as shown in the figure.

The thermosetting resin is P impregnated with general purpose vinyl ester resin.
Add the same weight of filler to the general-purpose vinyl ester resin on the outer periphery of a core material a made of AN-based carbon fiber, for example, having a diameter of 6 cm (carbon fiber content of about 65% by volume), and thicken the general-purpose vinyl ester resin to sufficiently impregnate the resin liquid. A coating layer of the above-mentioned PAN-based carbon fiber (carbon fiber content of about 40% by volume) is coated with a two-layer structure in cross section,
A concrete reinforcing member A made of carbon fiber reinforced plastic with a convex outer diameter of φ7.2 and a concave outer diameter of φ62 was manufactured by winding 1200 denier Tetron yarn at a pitch of 7 cm while applying tension in opposite directions. . The test results showed that the product was superior to conventional products in terms of concrete reinforcing members and their production.

〔Effect of the invention〕

The concrete reinforcing member of the present invention is different from conventional reinforcing bars in which a locking part is simply attached around a rod-shaped body. It is formed on a thermosetting resin coating layer, and the core material and coating layer are cured together by thermosetting, so the adhesion is strong and there is no delamination phenomenon, and it has strong durability under any usage conditions. It is a concrete reinforcing member with excellent practicality.

In addition, since the above-mentioned unevenness is formed by winding a tightening material around the outer periphery of the covering layer, it is easy to form unevenness in parallel in the longitudinal direction, and the reinforcing fibers of the covering layer are not loosened or sagging. If the core material is attached to the core material and the tightening material is wrapped around it, large irregularities will be formed, and as described above, this method of manufacturing a concrete reinforcing member can mass-produce a highly practical concrete reinforcing material.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is an explanatory diagram showing an example of the manufacturing process of the present invention, FIG. 2 is a front view showing an example of the concrete reinforcing member of the present invention, and FIG. 4 is a front view of another example, FIG. 5 is an explanatory sectional view of a state in which the core material a is covered with a coating layer, and FIG. FIG. 7 is a longitudinal sectional front view of another example in which a tightening material (c) is wrapped around the covering layer. a...Core material, b...Covering layer, C...Irregularities.

Claims (1)

[Claims] 1. Reinforcing fibers are arranged in the longitudinal direction around the outer periphery of a rod-shaped core material in which thermosetting resin is reinforced with reinforcing fibers arranged in the longitudinal direction, and the reinforcing fibers are made of thermosetting resin. Concrete reinforcement characterized by impregnating a resin with a resin, forming unevenness in the longitudinal direction by an appropriate means on the surface of the resin-impregnated coating layer, and thermally curing the coating layer and a rod-shaped core material integrally. Element. 2. The concrete reinforcing member according to claim 1, wherein the surface of the coating layer is provided with unevenness in the longitudinal direction by wrapping a tightening material around the coating layer. 3 Reinforcing fibers impregnated with thermosetting resin are passed through a die to form an uncured or semi-hardened core material, and reinforcing fibers are arranged longitudinally around the outer periphery of this core material. The fibers are impregnated with a thermosetting resin, a tightening material is wound at intervals around the outer periphery of this resin-impregnated coating layer, and unevenness is arranged in parallel in the longitudinal direction on the surface of the coating layer, and this coating layer and uncured or A method for manufacturing a concrete reinforcing member, characterized by heating a rod-shaped core material in a semi-hardened state to thermally harden them together. 4. The method for manufacturing a concrete reinforcing material according to claim 3, characterized in that the reinforcing fibers arranged in the longitudinal direction of the outer circumference of the core material are attached to the core material in a state where the tension is loose or in a slack state.