JPH07173824A - Ground reinforcer - Google Patents

Abstract

PURPOSE:To provide lightweight ground reinforcer excellent in water permeability, strength and execution efficiency. CONSTITUTION:A large number of perforations (3) are formed in a laminated sheet (1) constituted of a large number of longer reinforcing fibers laminating a plurality of fiber reinforced thermoplastic resin sheets (10 and 11) containing 20-80wt.% of a large number of longer reinforcing fibers arranged in one way and heated together as a unit. Ground reinforcer (15) has such a characteristic as belt-shaped fiber reinforced thermoplastic resin sheets (1 and 1) containing 20-80wt.% of a large number of longer reinforcing fibers arranged in one way are arranged and combined in the shape of a grille having opening sections (30 and 30). A covering sheet having water permeability can be also stuck on at least one surface. The quality of the material is the fiber reinforced thermoplastic resin sheet, so that it is lightweight as well as high strength, because water-holes are formed, it has good drainage, and reinforcing work of banking to a road or a shoulder, collapse prevention work of slope, work improving drainage of poor subsoil, etc., can be effectively and easily carried out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground reinforcing material used for reinforcing embankments on soft ground, roads, shoulders, etc., for ground improvement work on constructed land and for preventing landslides.

[0002]

2. Description of the Related Art Conventionally, in soft ground containing a large amount of water,
Stabilize the soil by throwing gravel into the soil to accelerate the discharge of water in the ground, and drive concrete or wooden piles on the steep slopes such as cliffs and road embankments, Reinforcement was done by providing frames and walls made of steel, wire mesh and resin nets, and spraying concrete.

However, recently, a method of covering or burying a slope with a polyester resin sheet has been widely used, and the corrosion resistance, abrasion resistance and lightness of the resin sheet have been evaluated, and various methods have been used. Products are being developed.

Such a resin sheet is generally excellent in water resistance, but it prevents the occurrence of slippage on the sheet by meshing the opposing soils on both sides divided by the sheet, and also the ground. In order to promote drainage inside, it is necessary to form a perforated part such as a lattice pattern or a knit pattern. However, if the perforated shape reduces the overall strength, an excessive load is concentrated at the intersections, so it is necessary to increase the amount of resin to increase the strength, but this increases the cost and increases the overall weight. Therefore, there arises a problem that the workability is deteriorated.

On the other hand, if a fiber-reinforced resin sheet is used, the strength can be increased without increasing the amount of resin.
Such a fiber reinforced product is generally a thermosetting resin, rather than a thermoplastic resin which has a high viscosity and a poor interfacial adhesion with the reinforcing fiber and which makes it difficult to achieve good wetting of the reinforcing fiber. Although the conventional method is to use, there is a problem that the hardness is too high and the workability is poor.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its object is to have excellent water permeability, high strength, light weight, and good workability. It is to provide ground reinforcement.

[0007]

Means for Solving the Problems As a result of intensive studies to solve this problem, the present inventors have found that the object can be achieved by imparting water permeability to a thin, lightweight, high-strength fiber-reinforced resin sheet. Found and completed the present invention.

That is, in the first embodiment of the present invention, a plurality of fiber-reinforced thermoplastic resin sheets containing 20 to 80% by volume of a large number of reinforcing fibers aligned in one direction are laminated and heat-integrated. A large number of punched holes are formed in the laminated sheet formed by the above.

According to the second aspect of the present invention, a belt-shaped fiber-reinforced thermoplastic resin sheet containing 20 to 80% by volume of a large number of reinforcing fibers aligned in one direction is formed into a lattice having openings. It is characterized in that the sequences are combined.

Furthermore, in the third aspect of the present invention, a large number of reinforcing fibers which are aligned in one direction are added in an amount of 20 to 20.
It is characterized in that a plurality of fiber-reinforced thermoplastic resin sheets containing 80% by volume are laminated and heat-integrated, and strip-shaped laminated sheets are arranged and combined in a lattice pattern having openings.

The laminated sheet is manufactured by laminating a plurality of fiber-reinforced resin sheets so that the orientation directions of the reinforcing fibers intersect. As the reinforcing fiber, polyamide synthetic fiber,
It is recommended to use at least one fiber selected from the group consisting of polyester-based synthetic fibers, glass fibers and carbon fibers. A polyolefin resin is used as the thermoplastic resin, and the thickness of the laminated sheet is 0.05
It is recommended that the thickness be ˜3 mm, that an adhesive sheet be provided between the layers of the laminated sheet, and that a water-permeable cover sheet be attached to at least one surface of the ground reinforcing material.

[0012]

With the ground reinforcing material having the above-mentioned structure, the material is a fiber reinforced thermoplastic resin sheet, so that it is lightweight and has high strength, and since the holes for passing water are formed, the drainage is good,
It is possible to effectively and easily carry out reinforcement work for embankments on roads and shoulders, slope fall prevention work, and work to improve drainage of soft ground.

[0013]

The present invention will be described in detail below. The fiber-reinforced thermoplastic resin sheet used in the present invention may be generally referred to as a prepreg, but a yarn or roving formed by bundling 200 to 12000 monofilaments having a diameter of 3 to 25 μm is arranged on a predetermined plane. Are aligned in one direction and impregnated with a thermoplastic resin. Regarding the ratio of the thermoplastic resin and the fiber, when the amount of the fiber is small, the strength is not sufficiently expressed, and when laminated and heat-pressed,
The flow of resin tends to disturb the arrangement of fibers. On the other hand, if the amount of fibers is large, the amount of resin is small, so that when laminated, the adhesion between layers deteriorates and the strength decreases. From this, the content of the reinforcing fiber is preferably 20 to 80% by volume.

As a method for laminating and integrating the fiber-reinforced thermoplastic resin sheets, a predetermined number of resin sheets are laminated,
The resin sheet is put into a press equipped with a heating plate heated to a temperature at which the thermoplastic resin impregnated therein is melted, and thermocompression bonding is performed at a pressure of 0.2 to 5 kg / cm ² per 1 cm ² of the surface area of the resin sheet. Then, it is cooled as it is, or the pressure of the press is released, the laminated sheet is taken out, immediately moved to a cooling press, and cooled under a pressure of 0.2 to 5 kg / cm ² per 1 cm ² of the surface area of the laminated sheet. There is a way to do it. By such a method, a plurality of fiber-reinforced resin sheets can be heated and integrated into a laminated sheet having a thickness of 0.05 to 3 mm.

The laminated sheet produced in this manner has a thin thickness of 3 mm or less, and the resin sheet can be cut by a punching machine, a cutter or any other commercially available tool that is industrially used. It is possible to easily make punched holes of a predetermined shape regularly. The shape of the punched hole includes a polygon such as a triangle, a quadrangle, a pentagon, a hexagon, and a star, and a shape formed by a curved line such as a circle and an ellipse, but is not particularly limited thereto. Alternatively, it is also possible to arrange the strip-shaped fiber-reinforced resin sheets in a grid pattern having openings and press-bond and bond them. In addition, a cover sheet can be attached to the surface of the laminated sheet, if necessary.

In the laminated sheet, the fiber orientation angles of the respective fiber-reinforced resin sheets to be laminated cross each other, that is, the fiber direction of a certain fiber-reinforced resin sheet is set to 0.
When the degree is defined as a degree, the fibers can be stacked so that the fiber orientation angle with another fiber-reinforced resin sheet intersects at an arbitrary angle within the range of 0 to 90 degrees, heat-pressed, and laminated and integrated. Further, the laminated sheet can have a thickness arbitrarily adjusted within the range of 0.05 to 3 mm depending on the number of fiber-reinforced thermoplastic resin sheets used, and also for the purpose of improving the adhesive strength, the fiber-reinforced resin sheet. It is also recommended to interpose an adhesive sheet between them, if necessary.

As the reinforcing fiber used in the present invention, a single fiber selected from polyamide-based synthetic fiber, polyester-based synthetic fiber, glass fiber, carbon fiber, or a fiber obtained by combining at least two of them is used. A sizing agent is usually used to facilitate the handling of the reinforcing fibers. The sizing agent must be selected according to the type of the thermoplastic resin to be impregnated, and generally, a sizing agent is selected that is softened at the melting temperature of the thermoplastic resin and easily impregnated into the fiber bundle of the reinforcing fibers. Therefore, as the sizing agent, a sizing agent whose main component is a resin of the same kind as the thermoplastic resin is often used.

When glass fiber is used as the reinforcing fiber, the surface of the fiber is subjected to various surface treatments to improve the adhesiveness with the thermoplastic resin. A sizing agent and a coupling agent are used in combination for the surface treatment. There are silane-based, titanate-based, and zirconium-based coupling agents, and it is necessary to select the optimum one according to the type of thermoplastic resin. The specific examples are listed below.

If the thermoplastic resin is a nylon resin or a polycarbonate resin, the coupling agent is γ-
Aminopropyl-trimethoxysilane, N-β- (aminoethyl) -γ-aminopropyl-trimethoxysilane and the like can be used. When the thermoplastic resin is polyethylene terephthalate or polybutylene terephthalate, the coupling agent is β- (3,4-epoxycyclohexyl) ethyl-trimethoxysilane, γ-glycidoxy-propyltrimethoxysilane, γ-aminopropyl. -Trimethoxysilane etc. can be used.

When the thermoplastic resin is polyethylene or polypropylene, vinyltrimethoxysilane, vinyl-tris- (2-methoxyethoxy) silane, γ-methacryloxy-propyltrimethoxysilane and the like can be used as the coupling agent. .

Further, the thermoplastic resin is polyphenylene oxide, polyphenylene sulfide, polysulfone,
Polyether sulfone, polyether ketone, polyether ether ketone, polyimide, polyarylate,
As long as it is a fluororesin, the above-mentioned coupling agent can of course be used, but in addition to it, N- (β-aminoethyl) -γ
-Aminopropylmethyldimethoxysilane, γ-chloropropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, p-aminophenyltriethoxysilane and the like can be used.

When a reinforcing fiber other than glass fiber is used, an amine-curable epoxy resin is often used as the coupling agent, and specific examples thereof include bisphenol-A-epichlorohydrin resin and epoxy novolac. There are resins, alicyclic epoxy resins, aliphatic epoxy resins, glycidyl ester type resins, and the like.

However, since thermoplastic resins generally have high melting temperatures and ordinary coupling agents are decomposed by heat, when impregnating the molten thermoplastic resin into reinforcing fibers other than glass fibers, The reinforcing fiber may not be surface-treated.

The method of applying the coupling agent to the fiber surface of the reinforcing fiber will be described below. This is because when the fiber material is melted and the monofilament is drawn out, an aqueous solution in which a surfactant is added to the sizing agent and the coupling agent is applied or sprayed on the drawn monofilament, and then dried at a temperature of about 100 ° C. There is a way to let it.

As another method, a liquid in which 0.1 to 3% by weight of a sizing agent and a coupling agent are dissolved in a reinforcing fiber,
After completely impregnating by means of dipping, spray coating, etc., it is allowed to evaporate the solvent at 60 to 120 ° C. for a sufficient time,
Specifically, there is a method in which it is dried for about 15 to 20 minutes and a coupling agent is reacted with the fiber surface. As a solvent for dissolving the coupling, depending on the type of coupling agent,
When using water whose pH is adjusted to about 2.0 to 12.0,
Organic solvents such as ethanol, tolueneacetone and xylene may be used alone or in a mixture.

There are various methods for producing a thermoplastic resin sheet by impregnating reinforcing fibers arranged in one plane in one direction with a thermoplastic resin, and a general method is shown below. . One is a method in which a resin that is soluble in a solvent is made into a solution to impregnate the reinforcing fibers, and then the solvent is removed while defoaming to form a sheet. Furthermore, one is to heat and melt the resin to impregnate the reinforcing fiber, degas,
This is a method of cooling to form a sheet.

The fiber-reinforced thermoplastic resin sheet produced in this manner has excellent adhesion between the fiber and the thermoplastic resin, and the fiber content can be changed according to requirements in the range of 20 to 90% by volume. Can be manufactured as thin as 0.03 to 1.0 mm.

When the reinforcing fibers are glass fibers, the thermoplastic resin sheet produced has a glass fiber content of 20.
If the content is less than or equal to volume%, the amount of fibers is small and the strength is low.
If it is 0% by volume or more, the amount of resin with respect to the fiber is small, the adhesion between the fiber and the resin is reduced, and the strength is reduced. Therefore, when the glass fiber is used as the reinforcing fiber, the glass content is 20 to 80% by volume, preferably 30 to 80% by volume, and the thickness may be 0.05 mm to 0.6 mm. Recommended.

Examples of the thermoplastic resin impregnated between the reinforcing fibers include polystyrene, polyvinyl chloride, high density polyethylene, polypropylene, polycarbonate, polybutylene terephthalate, polyether sulfone, polysulfone, and polyetherimide (registered trademark "Ultem"). )), Polyetheretherketone, polyphenylene sulfide, and the like, but are not necessarily limited thereto. As the most desirable resins, polypropylene-based and polystyrene-based resins are recommended from the viewpoints of strength, abrasion resistance, price, easiness of recycling when discarded.

Examples of the polypropylene resin include homopolymers of propylene, α of propylene and ethylene, butene and the like.
-In order to improve the adhesion between olefin copolymers and fibers and polypropylene resins, polypropylene resins are grafted with radically polymerizable unsaturated compounds such as maleic anhydride using an organic peroxide catalyst in a hydrocarbon solvent. An example is a polymerized grafted polypropylene resin.

As the polystyrene resin, a homopolymer of styrene, a polymer of styrene and acrylonitrile, a polymer of butadiene and styrene, a polymer of acrylonitrile and the like, and maleic anhydride for improving the adhesion to glass fiber are used. A grafted polystyrene resin obtained by graft-polymerizing a radically polymerizable unsaturated compound such as an acid can be used.

In the present invention, an adhesive sheet is used if necessary for the purpose of improving the adhesive strength between the layers of the laminated sheet. As the adhesive sheet, in the case of bonding with hot melt, a resin film made of a resin of the same system as the thermoplastic resin sheet in which reinforcing fibers are oriented in parallel in one direction, a resin sheet, or fibers impregnated with these resins Woven fabric, fibrous non-woven fabric and the like are preferable. When a normal adhesive is used, an adhesive-impregnated sheet having a carrier layer of a nonwoven fabric made of polyethylene terephthalate or glass cloth is preferable. If the adhesive sheet is thick, a large amount of the resin layer will be present in the laminate, so that the content of the reinforcing fibers will decrease, and the strength per unit cross-sectional area will decrease. Therefore, the thickness of the adhesive sheet is 0.005-0.1m
About m is preferable.

In the present invention, as the covering sheet to be stuck on one side or both sides of the laminated sheet, a covering sheet having a water-permeable function is used. For example, a woven cloth made of glass fiber or polyethylene terephthalate fiber or a non-woven cloth such as mat is used , A thermoplastic resin film, a metal foil such as aluminum or copper, or a composite sheet of these, and the like, those having no water permeability are processed into a perforated shape so as to have water permeability.

Thus, the ground reinforcing material also has a function of preventing the upper and lower soils of the ground reinforcing material from being mixed with each other. It will flow down through the punched holes in the ground reinforcement and cause landslides. Therefore, in order to prevent the flow of sediment that is smaller than the punching holes of the ground reinforcement material, the covering sheet is made of a porous base material that is integrated with the ground reinforcement material, and has a sediment flow prevention function and water flow function. What is given is good. The cover sheet may have a smooth surface, but may have an embossed surface to increase the coefficient of friction with the ground.

From the viewpoint of resource reuse, it is recommended that the fiber-reinforced thermoplastic ground reinforcement sheet and the thermoplastic resin used for the covering sheet that constitute one ground reinforcement be of the same type.

The present invention will be specifically described below with reference to the drawings. FIG. 1 is a perspective view showing a laminated state of a fiber-reinforced thermoplastic resin sheet used for a ground reinforcement material according to the present invention,
FIG. 2 is a perspective view showing an embodiment of the ground reinforcing material according to the present invention, which is manufactured by using this fiber reinforced thermoplastic resin sheet,
FIG. 3 is a perspective view showing a ground reinforcing material formed by sandwiching an adhesive sheet between fiber-reinforced thermoplastic resin sheets and thermocompression bonding, FIG.
6 is a perspective view showing a ground reinforcing material formed by further laminating and integrating the ground reinforcing material shown in FIG. 2 or 3 with an adhesive sheet, FIG. 5 is a top view of the ground reinforcing material shown in FIG. Is a perspective view showing another embodiment of the ground reinforcing material according to the present invention, which is obtained by arranging and crimping a band-shaped fiber-reinforced thermoplastic resin sheet in a grid pattern having openings, and FIG. 7 is the ground shown in FIG. FIG. 8 is a perspective view showing a ground reinforcing material in which a covering sheet is attached to one surface of a reinforcing material, and FIG. 8 is a perspective view showing a ground reinforcing material in which a covering sheet is attached to one surface of the ground reinforcing material shown in FIG. 9 is shown in FIG.
FIG. 10 is a perspective view showing the ground reinforcing material in which the covering sheets are adhered to both sides of the ground reinforcing material shown in FIG. 10, and FIG. 10 shows the ground reinforcing material in which the covering sheets are adhered to both sides of the ground reinforcing material shown in FIG. It is a perspective view.

In the figure, 1 is a heat-integrated laminated sheet which is the basis of the ground reinforcement of the present invention, 10 and 11 are thermoplastic resin sheets, and 10-1 and 11-1 are its sheets. It is a reinforcing fiber embedded inside. When the fiber orientation direction of the uppermost thermoplastic resin sheet 10 is set to 0 degree,
The sheet 11 underneath is laminated and integrated into three layers so that the orientation direction of the fibers is 90 degrees and the orientation direction of the sheet 10 under it is 0 degree.

The thermoplastic resin sheet 10 uses glass fiber having a diameter of 13 μm as the reinforcing fiber 10-1, for example.
The yarn obtained by bundling 1600 of this was surface-treated with γ-methacryloxy-propyltrimethoxysilane, and the yarns were evenly stretched and aligned so as to elongate in the fiber direction. It is impregnated by bringing it into contact with a molten polypropylene resin added by volume%, and the fiber content is 50 to 80 in consideration of the balance between production stability, workability and strength.
It is produced so as to have a volume%, preferably 70 to 80% by volume. The thermoplastic resin sheet thus produced usually has a thickness of 0.01 to 0.03 mm.

The fiber directions of the thermoplastic resin sheet 11 are aligned so as to be orthogonal to that of the thermoplastic resin sheet 10. The laminated sheet 1 is produced by laminating the thermoplastic resin sheets 10 and 11 so that the reinforcing fibers 10-1 and 11-1 thereof are orthogonal to each other, and press-bonding the thermoplastic resins in a molten state to integrate them. To do. In addition, when the fiber-reinforced resin sheets are laminated, it goes without saying that the fibers of the respective sheets may intersect at an arbitrary angle within the range of 0 to 90 degrees, in addition to the orthogonal orientation of the fibers.

Next, FIG. 2 will be described. 12 in the figure
Is a ground reinforcing material having a large number of punched holes 3 obtained by punching the laminated sheet of FIG. The punching process can be performed using a roll-type punching device in which a roll equipped with a blade die for punching a hole of a predetermined shape and a rubber roll are paired. The shape of the punched hole is not limited to the rectangular shape shown in FIG. 2, but may be any triangular shape, quadrangular shape, pentagonal shape, hexagonal shape, polygonal shape such as star shape, circular shape, elliptical shape, etc. It goes without saying that the size and the size can be made different, and various shapes can be freely combined and mixed.

Next, FIG. 3 will be described. 13 in the figure
Shows a ground reinforcement material obtained by punching after the adhesive sheet 2 is provided between the thermoplastic resin sheets 10, 11 and 10 and integrated. By providing the adhesive sheet 2, the adhesive strength between the layers of the laminated sheet can be further improved. As the adhesive sheet, it is preferable to select the most suitable one according to the type of thermoplastic resin used for the fiber reinforced resin sheet. For example, it is preferable to use a polypropylene sheet when the thermoplastic resin is polypropylene.

FIG. 4 shows a case where a stronger ground reinforcement material is required depending on the condition of the ground to be constructed.
2 or FIG. 3, a plurality of ground reinforcing materials 13 are placed on an adhesive sheet at a place other than the punched holes, and integrated to manufacture a stronger ground reinforcing material 14. As a method of integrating a plurality of ground reinforcements 12 or 13, it is recommended to pass between a pair of heat rolls.

The present invention is not limited to these examples. For example, the thickness of the laminated sheet is 0.05-3m
It can be freely combined and adjusted within the range of m, and it is also possible to utilize the portion where the punched hole is not formed for joining with another material or laminating.

Further, if necessary, a plurality of the above-mentioned ground reinforcement materials may be further laminated and integrated for use. The number of fiber-reinforced thermoplastic resin sheets to be used, the kind of thermoplastic resin, and the kind of reinforcing fiber are used. The size, shape and configuration of the adhesive sheet can be freely modified within the scope of the object of the present invention.

Next, FIG. 6 will be described. 15 in the figure
Is a product in which the ground reinforcing material of the present invention is manufactured without forming the openings 30 and 30 by arranging and joining the band-shaped fiber-reinforced resin sheets in a lattice shape and punching the laminated sheets.
The ground reinforcing material 15 is formed in a grid pattern so that the reinforcing fiber resin sheet is heated to a temperature higher than the melting point of the resin and the openings 30, 30 are formed as shown in the figure in the state where the resin is melted. It is made by arranging and stacking, stacking, crimping, and cooling.
Since these have a lattice-like structure, they are suitable for protecting slopes and reinforcing soft ground.

Next, FIG. 7 will be described. 16 in the figure
A is a ground reinforcement material obtained by heating the ground reinforcement material 12 shown in FIG. 2 until the thermoplastic resin is melted, and pressing the cover sheet 4 made of non-woven fabric on one side thereof.

Further, 16B in FIG. 8 is a ground reinforcement material obtained by heating the ground reinforcement material 15 shown in FIG. 6 until the thermoplastic resin is melted, and pressing the cover sheet 4 made of non-woven fabric on one side thereof. Is. Since the ground reinforcing material shown in FIGS. 7 and 8 is covered with the nonwoven fabric 4, it is possible to prevent the outflow of small sand grains without impairing the water permeability.

Next, FIG. 9 will be described. 17 in the figure
A is the same method as the ground reinforcement 16A shown in FIG.
This is a ground reinforcement material obtained by pressure-bonding the covering sheets 4 and 4 ′ made of a nonwoven fabric on both sides of the ground reinforcement material 12 shown in FIG.

In FIG. 10, 17B is a method similar to that for the ground reinforcing material 16B shown in FIG. 8 and the cover sheets 4, 4'composed of non-woven fabric are pressure-bonded to both surfaces of the ground reinforcing material 15 shown in FIG. It is a ground reinforcement material. These cover sheets 4,
4'may be the same, but it is also recommended that, for example, one is a woven fabric made of coarse, thick and tough fibers and the other one is a fine and dense woven fabric.

The ground reinforcement 17B shown in FIG.
On one side of each of the two cover sheets 4 and 4 ',
After a plurality of belt-shaped fiber-reinforced resin sheets in which the resin is melted are arranged in parallel and at equal intervals and pressure-bonded, the two cover sheets 4 and 4'are contacted at right angles with each other. It can also be manufactured by stacking and crimping as described above.

The effects of the ground reinforcing material according to the present invention will be described below based on specific manufacturing examples. The thermoplastic resin sheet containing reinforcing fibers arranged in one direction used in the present invention,
As described in JP-A No. 61-229535, a yarn in which 1600 monofilaments with a thickness of 13 .mu.m obtained by surface-treating glass fiber with .gamma.-methacryloxy-propyltrimethoxysilane are bundled is pulled by a predetermined number of uniform tensions. However, they were aligned in one direction, and this was produced by contacting a polypropylene resin containing 1% of polypropylene resin grafted with hot-melt maleic acid and impregnating the resin with a hot roll while squeezing the resin. The fiber content of this sheet was 70% by volume and the thickness was 0.2 mm.

Example 1 Three fiber-reinforced thermoplastic resin sheets were used, as shown in FIG.
The layers were arranged so that they would be 0 degrees, and they were laminated and integrated. The conditions for integration are 0.1 kg / c at a hot plate temperature of 200 ° C.
After applying a pressure of m ² for 2 minutes, the pressure was released, the laminate was taken out, moved into a cooling press, and cooled at a pressure of 0.1 kg / cm ² for 20 seconds to obtain a laminated sheet. This laminated sheet was punched into a lattice shape shown in FIG. 5 with a roll-type punching device to manufacture the ground reinforcement material of the present invention. The size of the punched holes was a square of 20 mm. This ground reinforcing material was subjected to a tensile fracture test with the fiber at 0 ° as the tensile direction, and as a result, the fracture load was converted to a width of 1 m and was 1500 kg.
Met.

Example 2 As shown in FIG. 3, in order to improve adhesion, an adhesive sheet made of polypropylene having a thickness of 60 μm was sandwiched between the layers of the laminated sheet, and ground reinforcement was carried out in the same manner as in Example 1. The wood was manufactured. The same tensile fracture test as in Example 1 was performed to obtain a fracture load of 2300 kg in terms of a width of 1 m.

[Example 3] A fiber-reinforced thermoplastic resin sheet was formed into a strip having a width of 20 mm, and the sheets were arranged in a grid as shown in Fig. 6, and the press hot plate temperature was 200 ° C, and the pressure was 0.1 kg / c.
After applying a pressure of m ² for 2 minutes, the pressure is released, the laminate is taken out, moved into a cooling press, and cooled at a pressure of 0.1 kg / cm ² for 20 seconds to obtain a grid-like ground reinforcement material. Obtained. A tensile fracture test was performed in the same manner as in Example 1 to obtain a fracture load of 1000 kg in terms of a width of 1 m.

[0055]

Since the present invention is constructed as described above, according to the present invention, ground reinforcement suitable as a sheet for civil engineering works, a sheet for preventing landslides on slopes, and a sheet for reinforcing other soft ground. Material can be provided. This ground reinforcement material is lightweight and relatively flexible, so construction is easy, and the water that seeps from the ground passes through the ground reinforcement material and flows to the outer surface, so the ground does not contain water and become weak. . Thus, by using the ground reinforcement material according to the present invention, it is possible to easily carry out light and high-strength road and shoulder embankment reinforcement work, slope collapse prevention work, and work to improve the drainage of soft ground. You can

It should be noted that the present invention is not limited to the above embodiments, but includes all modified embodiments that can be easily conceived by those skilled in the art from the above description and the description of the drawings.

[Brief description of drawings]

FIG. 1 is a perspective view showing a laminated state of a fiber-reinforced thermoplastic resin sheet used for a ground reinforcement material according to the present invention.

FIG. 2 is a perspective view showing an embodiment of a ground reinforcing material according to the present invention manufactured by using this fiber reinforced thermoplastic resin sheet.

FIG. 3 is a perspective view showing a ground reinforcing member formed by sandwiching an adhesive sheet between fiber-reinforced thermoplastic resin sheets and performing thermocompression bonding.

FIG. 4 is a perspective view showing a ground reinforcing material obtained by further laminating and integrating the ground reinforcing material shown in FIG. 2 or 3 with an adhesive sheet.

5 is a top view of the ground reinforcing material shown in FIG. 2. FIG.

FIG. 6 is a perspective view showing another embodiment of the ground reinforcement material according to the present invention, which is formed by arranging and crimping strip-shaped fiber-reinforced thermoplastic resin sheets in a lattice shape having openings.

FIG. 7 is a perspective view showing a ground reinforcing material in which a cover sheet is attached to one surface of the ground reinforcing material shown in FIG.

8 is a perspective view showing a ground reinforcing material in which a covering sheet is attached to one surface of the ground reinforcing material shown in FIG.

9 is a perspective view showing a ground reinforcing material in which cover sheets are attached to both surfaces of the ground reinforcing material shown in FIG.

10 is a perspective view showing a ground reinforcing material in which cover sheets are attached to both sides of the ground reinforcing material shown in FIG. 6.

[Explanation of symbols]

 1 Laminated sheet 2 Adhesive sheet 3 Punch hole 30 Opening 4 Covering sheet 4'Coating sheet 10 Fiber reinforced thermoplastic resin sheet 10-1 Reinforcing fiber 11 Fiber reinforced thermoplastic resin sheet 11-1 Reinforcing fiber 12 Ground reinforcement 13 Ground reinforcement Material 14 Ground reinforcement material 15 Ground reinforcement material 16A Ground reinforcement material 16B Ground reinforcement material 17A Ground reinforcement material 17B Ground reinforcement material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kojiro Shigetai, Kasumigaseki 3-chome, 2-5, Chiyoda-ku, Tokyo Mitsui Toatsu Chemical Co., Ltd. Toatsu Chemical Co., Ltd. (72) Inventor Hiroshi Tanabe 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (9)

[Claims] 1. A plurality of fiber-reinforced thermoplastic resin sheets (10, 11) containing 20 to 80% by volume of a large number of reinforcing fibers (10-1, 11-1) aligned in one direction are laminated. A ground reinforcing material (1) characterized in that a large number of punched holes (3) are formed in a laminated sheet (1) formed by heating and integrating.
2). 2. A strip-shaped fiber-reinforced thermoplastic resin sheet (1, 1) containing 20 to 80% by volume of a large number of reinforcing fibers aligned in one direction and having an opening (30, 30) in a lattice form. Ground reinforcements (1)
5). 3. A strip-shaped laminated sheet having a plurality of fiber-reinforced thermoplastic resin sheets containing 20 to 80% by volume of a large number of reinforcing fibers aligned in one direction, which are heat-integrated and have openings. A ground reinforcement material that is arranged and connected in a grid pattern. 4. The ground reinforcement material according to claim 1, wherein the laminated sheet is formed by laminating a plurality of fiber-reinforced resin sheets so that the orientation directions of the reinforcing fibers intersect with each other. 5. The ground reinforcing material according to claim 1, wherein the laminated sheet has a thickness of 0.05 to 3 mm. 6. The ground reinforcement material according to claim 1, wherein an adhesive sheet (2) is provided between the respective layers of the laminated sheet. 7. The reinforcing fiber is at least one fiber selected from the group consisting of polyamide synthetic fiber, polyester synthetic fiber, glass fiber and carbon fiber.
The ground reinforcement material according to any one of 1 to 6. 8. The ground reinforcement material according to claim 1, wherein the thermoplastic resin is a polyolefin resin. 9. The ground reinforcement material (16A, 17A, 16) according to any one of claims 1 to 8, wherein a water-permeable cover sheet (4, 4 ') is attached to at least one surface of the ground reinforcement material.
B, 17B).