JP2965173B2 - Fiber reinforced resin reinforced cement based structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber-reinforced resin-reinforced cementitious structure, and more particularly, to a concrete slab, a bridge pier, a wall material made of mortar, etc., reinforced with a fiber-reinforced resin layer. A cement-based structure.

[0002]

2. Description of the Related Art Recently, the destruction of bridges due to earthquakes, the generation of rust in reinforcing bars due to the neutralization of concrete, the fatigue of reinforcing steel reinforcing the decks of bridges due to the rapid increase in traffic, and the outer walls of buildings. The fragility and durability of cement-based structures, such as falling due to cracks in wall materials, have become social issues. Of course, you can replace it with a new one, but that would require enormous costs. Therefore, as a countermeasure, for example, a deck slab of a bridge is usually reinforced by a method of bonding a steel plate as a reinforcing material to the lower surface of a slab made of concrete with an adhesive.

However, over a long period of time, the concrete slab cracks and water penetrates from there, and when it reaches the bonding surface between the slab and the steel sheet, the steel sheet peels off from the slab due to volume expansion due to freezing of water. However, when the permeation and freezing of water are further repeated in the peeled portion, the peeled area of the steel sheet is further increased, and the reinforcing effect is gradually lost. Since the steel plate is opaque, it is impossible to find a leaking portion of the steel plate, and there is a possibility that the user may not be aware that the steel plate is in danger of destruction. Conventionally, a method of hitting a steel plate with a hammer and finding a peeling point with a hitting sound has been adopted.However, since judgment is made by a human being based on a change in sound, not only skill is required but also reliability is lacking. There was a problem that it could not be grasped accurately.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems by sufficiently reinforcing a cement-based structure and at the same time, at the same time as cracks, water leaks, and reinforcing members of the structure. An object of the present invention is to provide a cement-based structure capable of easily and accurately finding a peeled portion of a barrel FRP layer.

[0005]

According to the present invention, there is provided a fiber-reinforced resin-reinforced cement-based structure according to the present invention, in which a fiber-reinforced resin layer containing a reinforcing fiber base is adhered to an outer surface of a structure made of a cement-based material. Wherein the reinforcing fiber base comprises a carbon fiber yarn group and another fiber yarn group, and at least a part of the reinforcing fiber base material comprises the other fiber yarn group. Consisting of a fiber base material arranged so as to be formed only from the above, the other fiber yarn group, when molded as a fiber reinforced resin layer, the other fiber yarn group portion of the fiber reinforced resin layer It is made of a transparent or translucent fiber yarn.

[0006] The cement-based structure referred to in the present invention is a structure made of a cement-based material such as mortar or concrete, and refers to a building material used for a building, civil engineering structure, wall, or the like. Further, the cement-based structure of the present invention is an FRP reinforced cement-based structure in which a fiber reinforced resin (FRP) layer containing a reinforcing fiber base material is formed on an outer surface thereof by bonding. The FRP layer is formed by impregnating a reinforcing fiber base material with a resin. The reinforcing fiber base may be a single layer, but from the viewpoint of reinforcing the cement-based structure, it is preferable that the reinforcing fiber base has a laminated structure of a plurality of reinforcing fiber bases.

The reinforcing fiber base in the present invention comprises a group of carbon fiber yarns and a group of fiber yarns other than carbon fiber. Are arranged so as to be formed only from the fiber yarn group. The carbon fiber thread group is arranged for reinforcing the cement-based structure. The other fiber yarn group is required to be made of a fiber yarn in which the other fiber yarn group portion of the FRP layer becomes transparent or translucent when formed into the FRP layer.

The carbon fiber yarn used in the present invention is PAN
It is a yarn made of a (polyacrylonitrile) or pitch-based carbon fiber with high elastic modulus and high strength. The yarn form may be either a multifilament or a monofilament, but is preferably a multifilament having an elastic modulus of 20 × 10 ³ kg / mm ² or more and a tensile strength of 250 kg / mm ² or more. It is preferable that 2,000 fibers converge to form a carbon fiber thread.

The other fiber yarn used in the present invention is FR
It is a fiber thread that becomes transparent or translucent when formed into P, and does not necessarily need to contribute to reinforcement of the cement-based structure. Further, when processed into a reinforcing fiber base material, in order to prevent the occurrence of meandering of the carbon fiber yarn due to the difference in the heat shrinkage, a fiber yarn having substantially the same heat shrinkage as the carbon fiber yarn is preferable. The fibers constituting the strip include glass fibers, polyaramid fibers, vinylon fibers, liquid crystal polyester fibers, and the like. Further, a fiber yarn or a crimped yarn obtained by heat-treating a thermoplastic fiber such as a nylon fiber or a polyester fiber to reduce the heat shrinkage may be used.

Since carbon fiber has a high elastic modulus and a high strength, it is effective even in a small amount for reinforcing a cement-based structure having a high elastic modulus, and is excellent in alkali resistance and fatigue properties. The fiber is black and opaque, so if the entire area of the reinforcement is reinforced with carbon fiber reinforced resin, it will be possible to find water leaking points, just as with steel plate. No, maintenance is a problem. Therefore, even after FRP, water leakage spots can be found by visual observation.
It is necessary to provide a transparent or translucent FRP portion in the P layer.

The fiber-reinforced resin-reinforced cementitious structure of the present invention having such a structure has a structure as shown in FIGS. 1 and 2, for example. In the embodiment shown in FIGS. 1 and 2, the FRP layer is configured as a layer including a laminate of a plurality of reinforcing fiber substrates.

In the embodiment shown in FIG.
, Five laminated fiber base materials 3 ₁ , 3 ₂ ,
_{3 3, 3 4, 3 5} FRP layer 2 containing is formed by gluing. Each of the five reinforcing fiber substrates 3 ₁ , 3 ₂ , 3 ₃ ,
3 _4, 3 _5, a strip in the longitudinal direction A of the cement-based structures, and arranged remembering intervals in the width direction B carbon fiber yarn groups 4 _1, 4 _2, 4 _3, 4 _4, 4 ₅ and a group of other fiber yarns other than carbon fiber ₅ alternately arranged
_1, 5 _2, it consists of five _3, 5 _4, 5 ₅ which, each of the reinforcing fiber substrate such that the carbon fiber thread group moiety to each other and other fiber yarns group moiety to each other overlap each other are laminated. Then, when formed into the FRP layer, the portion where the other fiber yarn group portions overlap each other becomes transparent or translucent.

In the embodiment shown in FIG. 2, each reinforcing fiber base material 13 ₁ , 13 ₂ , 13 ₃ , 13 ₄ ,
13 ₅ of the belt-like carbon fiber thread group 14 _1, 14 _2, 14 _3,
14 ₄ and 14 ₅ are arranged in two directions of the length direction A and the width direction B of the cement-based structure 1. Other fiber yarn group 1
5 ₁ , 15 ₂ , 15 ₃ , 15 ₄ , and 15 ₅ are arranged only in the length direction A of the cementitious structure 1, but they may also be arranged in two directions of the width direction B. . Since the belt-like carbon fiber yarn groups are arranged in two directions with an interval, a rectangular portion consisting only of another fiber yarn group is formed between each carbon fiber yarn group, and each reinforcing fiber Portions of the substrate, which are composed only of the other fiber yarn groups, are laminated so as to overlap each other.

The above carbon fiber yarn and other fiber yarns are
It is preferable to use a material which has been processed into a fiber base material in advance, since the reinforcing work is simplified. For example, the FRP shown in FIG.
To form the layers, a unidirectional fabric as shown in FIG. 3 is used. The unidirectional woven fabric in FIG. 3 includes a yarn group a in which a plurality of carbon fiber yarns 6 are arranged in parallel, and a yarn group b in which a plurality of yarns 7 made of other fibers are arranged in parallel. Are alternately arranged, and a warp composed of a carbon fiber yarn and another fiber yarn,
The wefts 8 as auxiliary yarns are interlaced and have a flat structure. In addition, in order to make the FRP portion composed of another fiber yarn group transparent or translucent, it is preferable that the weft yarn is also a fiber yarn that becomes transparent or translucent when made into FRP.

In order to provide the FRP layer 12 shown in FIG. 2 in which the carbon fiber thread groups are arranged in two directions of the length direction and the width direction of the cementitious structure 1, the unidirectional woven fabric of FIG. It can also be obtained by alternately laminating in the length direction and the width direction, and the carbon fiber yarn group and the other fiber yarn group alternately,
It can also be obtained by laminating two-way fabrics arranged in two directions, a vertical direction and a horizontal direction.

In the reinforcing fiber substrate used in the present invention,
The thickness of the woven fabric made of the carbon fiber yarn group and the woven fabric made of the other fiber yarn group do not necessarily have to be the same. If the part is thinner than the part of the woven fabric consisting of the carbon fiber thread group, the FRP layer part consisting of the other fiber thread group becomes thinner even when the FRP layer is formed, and it becomes easier to find water leaking points etc. preferable.

Further, the form of the reinforcing fiber base is not limited to a woven fabric. A group of yarns in which a plurality of carbon fiber yarns are arranged in parallel and a plurality of other fiber yarns are arranged in parallel. Formed by alternately arranging thread groups consisting of fibers and attaching them with a thread to which an adhesive has been attached, or by attaching a thin woven fabric, nonwoven fabric or mat made of fibers that become transparent or translucent when made into FRP. A sheet-shaped unidirectional substrate may be used.

Since the carbon fibers of the reinforcing fiber base used in the present invention serve to reinforce the cement-based structure, 50 to 90% by volume of the fibers of the entire fiber base is used.
It is preferred that When it is 90% or more, the area of the transparent or translucent FRP portion becomes small, and it is difficult to find a leaking portion or the like, which is not preferable. In addition, in order to make it easy to find a water leaking part, the width of one band group of other fiber yarn groups is preferably 10 mm to 300 mm, more preferably 50 mm to 250 mm. If it is smaller than this, the area of the transparent or translucent FRP portion becomes smaller due to the displacement of each layer when the reinforcing fiber base material is laminated,
It is difficult to find water leak points.

The fiber-reinforced resin-reinforced cementitious structure of the present invention can be prepared, for example, as follows. First, as a repair before entering the lamination of the reinforcing fiber base, if cracks are found in the reinforcing part of the cement-based structure, bury epoxy resin-based putty in the cracks to prevent water leakage . In addition, when the surface of the cement-based structure is uneven, the reinforcing fiber base material has a drape property, so it follows some unevenness, but when the degree of the unevenness is large, the surface of the cement-based structure is shaved with a grinder. Smoothing,
In order to improve the adhesion with the FRP layer, an epoxy resin-based primer is applied.

A required number of wide reinforcing fiber base materials are laminated on the cement-based structure to be reinforced, a bleeder is placed around the base material, these are covered with a bag film, and the cement-based structure is provided with a sealing material disposed outside the bleeder. The body and the bag film are adhered, and the reinforcing fiber base and the bleeder are bagged with the film. Attach the suction port at the bleeder and the resin introduction port at the reinforcing fiber base, and supply the resin from the resin tank while evacuating the bag with a vacuum pump from the suction port.
The reinforcing fiber substrate is impregnated with resin. The resin flows from the resin introduction port to the suction port while impregnating the reinforcing fiber base material, and the entire surface of the reinforcing fiber base material is impregnated with the resin. According to this method,
Since the reinforcing fiber base material can be used in a wide state, a molding operation for reinforcement can be easily performed.

If a thermosetting resin of a room temperature curing type is used as the resin serving as the matrix of the FRP, the resin is cured if left at an outside temperature in the state after the injection, so that the repair work of the cement-based structure can be performed. Although it is simple and preferable, it is also possible to use a heat-curable thermosetting resin and heat-cur using a hot plate or the like as necessary. Examples of the thermosetting resin used in the present invention include an epoxy resin, an unsaturated polyester resin, and a phenol resin. Among them, an epoxy resin is preferable because of its good adhesion to a cement-based structure or carbon fiber. In addition, in general, for repair and reinforcement of cement-based structures, dripping flow from the top to the bottom of the resin,
In order to prevent scattering of the resin during the impregnation work, an opaque filler such as calcium carbonate is used, and a high-viscosity resin is used, which impairs the resin impregnation into the reinforcing fiber base material.
In the above method, there is no need to use an opaque filler,
Molding is possible with a relatively transparent low viscosity resin of 3 to 20 poise. Since the viscosity of the resin is low, the impregnation of the reinforcing fiber base material with the resin is also improved.

After the matrix resin is cured by a vacuum bag, the bag film can be peeled off, and the surface of the FRP layer can be coated with a urethane-based paint or an acrylic paint. However, it is necessary to leave the bag film without peeling. Thereby, deterioration of the matrix resin due to ultraviolet rays can be prevented, and a decorative effect can be provided. Such a method is preferable because not only deterioration due to wind and rain but also deterioration due to ultraviolet rays are small. Further, the color of the carbon fiber is black, which does not change even after FRP. Therefore, if the color of the bridge or the like after the repair becomes black and there is a possibility of giving discomfort, the discomfort can be reduced by making the film a gray color similar to concrete. Further, by using films of various colors as needed, it is possible to improve the amenity.

The fiber-reinforced resin-reinforced cementitious structure of the present invention can take various forms other than those described above. For example, in order to make it easier to find a water leaking point or the like, the FRP portion made of another fiber yarn group has a diameter of 5 to 10 mm.
A hole of about mm that penetrates the FRP portion and reaches the cement-based structure may be formed. F consisting of other fiber yarn groups
Since the RP portion does not basically support the reinforcement, there is almost no fear that the reinforcing effect of the FRP layer is reduced by making the holes. In addition, an FRP composed of another fiber yarn group
In order to prevent the layer from dropping, the cement-based structure and the fastening by bolts may be combined.

[0024]

According to the fiber-reinforced resin-reinforced cement-based structure of the present invention, the cement-based structure contains a reinforcing fiber base material comprising a group of carbon fiber yarns and a group of other fiber yarns.
The layer was formed by bonding, and a transparent or translucent portion having only another fiber yarn group was formed in the FRP layer. Therefore, the cement-based structure was reinforced by the FRP layer having the carbon fiber yarn group. At the same time, through the transparent or translucent FRP portion, it is possible to easily and accurately find a cracked portion, a water leaked portion, a peeled portion of the FRP layer as a reinforcing material, etc. of the cement-based structure due to long-term use. it can.

[Brief description of the drawings]

FIG. 1 is a perspective view of a fiber-reinforced resin-reinforced cement-based structure according to an embodiment of the present invention.

FIG. 2 is a perspective view of a fiber-reinforced resin-reinforced cement-based structure according to another embodiment of the present invention.

FIG. 3 is a plan view showing an example of a reinforcing fiber base according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cement-based structure 2, 12 Fiber reinforced resin (FRP) layer 3₁, 3_Two, 3_Three, 3_Four, 3_Five, 13₁, 13_Two, 13
_Three, 13_Four, 13_Five Reinforcing fiber substrate 4₁, 4_Two, 4_Three, 4_Four, 4_Five, 14₁, 14_Two, 14
_Three, 14_Four, 14_FiveCarbon fiber thread group 5₁, 5_Two, 5_Three, 5_Four, 5_Five, 15₁, 15_Two, 15_Three, 15
_Four, 15_FiveOther fiber yarn group 6 Carbon fiber yarn 7 Other fiber yarn 8 Auxiliary yarn

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification symbol FI E04G 23/02 E04G 23/02 H (58) Field surveyed (Int.Cl. ⁶ , DB name) B32B 1/00-35 / 00 E04G 23/00-23/08

Claims (2)

(57) [Claims] 1. A cement-based structure in which a fiber-reinforced resin layer containing a reinforcing fiber base is formed by bonding on an outer surface of a structure made of a cement-based material, wherein the reinforcing fiber base is made of carbon fiber. The yarn group and another fiber yarn group are made of a fiber base material arranged such that at least a part of the reinforcing fiber base material is formed only from the other fiber yarn group, and the other fiber yarn The fiber group is a fiber-reinforced resin-reinforced cement, characterized in that when formed as a fiber-reinforced resin layer, the other fiber yarn group portion of the fiber-reinforced resin layer is made of fiber yarns that become transparent or translucent. System structure. 2. The fiber reinforced resin layer includes a laminate of a plurality of the reinforcing fiber bases, and each reinforcing fiber base includes a carbon fiber yarn group and the other fiber yarn group alternately arranged. 2. The fiber-reinforced resin reinforcement according to claim 1, wherein the laminated body of the reinforcing fiber bases is stacked such that the other fiber thread groups of the reinforcing fiber bases overlap with each other. Cement-based structure.