Concrete slit tension member

Abstract

To easily add yield strength equivalent to that of a reinforcing bar member to concrete without increasing the volume and mass of the concrete by inserting a tension member into a slit hole formed in a concrete surface layer and fitting it with the concrete without requiring a fastening member or a fixing structure.SOLUTION: Provided is a concrete slit tension member capable of applying yield strength equivalent to that of a reinforcement member to a floor, a wall, a column, a plane part of a ceiling, and a curved surface part of a tunnel, and preventing the tension member from being exposed on a concrete surface by inserting the tension member of fiber reinforced plastic into a slit hole formed on a concrete surface layer and fitting it with concrete.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The invention disclosed herein relates to a concrete slit tension member.

Background Art

[0002] To restore the reduced strength of the reinforcing member of reinforced concrete to equivalent strength, it is difficult to restore it without increasing the volume and mass of the structure.

[0003] It is difficult to restore the same strength as that of a reinforcing member only by adhering a plate-like or sheet-like tension member of fiber-reinforced plastic to the surface layer of the structure. Also, in the case of a rod-shaped or plate-shaped tension member of fiber-reinforced plastic, since it is engaged or connected to concrete by a method that combines adhesion or a metal anchor or a fixing structure, multiple steps are required. Furthermore, since the member is exposed on the surface of the concrete, some treatment is also required to prevent deterioration due to exposure or fire damage.

[0004] Patent Document 1 discloses a reinforcement method that can suppress cracks on the concrete surface layer and enable observation of the progress of cracks. By using a method of adhering a multi-layer sheet in which lattice-shaped carbon fibers are woven into a visible non-woven fabric base material to the concrete surface layer with a visible adhesive, crack suppression and crack observation are added. However, the sheet needs to be woven with a non-woven fabric and an adhesive, and deterioration due to exposure or fire damage occurs. Also, since a non-woven fabric with a low elastic modulus is laminated, the reinforcement effect is small. However, if it is a concrete slit tension member, it is considered that the same strength as that of a reinforcing member can be easily added to the concrete, and since the tension member is not exposed on the concrete surface, there is no deterioration, so it can be installed over a wide range.

[0005] Patent Document 2 discloses a method for reinforcing the concrete surface layer. A fastening structure for transmitting the tension force of a net-shaped reinforcing member to the concrete by using a method of engaging the net-shaped reinforcing member, which is formed by knitting two fiber-reinforced synthetic resin bars into a lattice shape, with the concrete using a metal anchor is required. And since the net-shaped reinforcing member is exposed on the surface layer, when it is coated with an inorganic fluid hardening material, the volume and mass of the structure increase. However, in the case of a concrete slit tension member, the same bearing capacity as that of a reinforcing bar member can be easily added to the concrete, and since the tension member is not exposed on the concrete surface, there is no deterioration, so it is considered that it can be installed over a wide range.

[0006] Patent Document 3 discloses a method for reinforcing a structure with a rod-shaped fiber-reinforcing member. A fixing structure for applying a reaction force to the rod-shaped member using a tension applying device equivalent to the length in the long side direction of the fiber-reinforcing member and transmitting the stress to the concrete is required, and multiple steps are required, such as using a pre-pasted sheet, a peeling prevention sheet, and a resin frame mortar and a post-pasted sheet. However, in the case of a concrete slit tension member, the same bearing capacity as that of a reinforcing bar member can be easily added to the concrete, and since the tension member is not exposed on the concrete surface, there is no deterioration, so it is considered that it can be installed over a wide range.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0008] In view of the above background, the present invention inserts a tension member made of a high Young's modulus fiber-reinforced plastic into a slit hole formed in the concrete surface layer and fits it with the concrete, so that neither a fastening member nor a fixing structure is required, and the volume and mass of the structure are not increased. The same shear strength as that of a reinforcing member can be easily added to flat and curved parts of floors, walls, columns, and ceilings. In addition, since the tension member is not exposed on the concrete surface, it is considered that it can be installed over a wide range because there is no deterioration.

Means for Solving the Problems

[0009] The concrete slit tension member according to the present invention is characterized in that a tension force is added to the concrete by inserting the tension member into a slit hole formed in the concrete surface layer and fitting it with the concrete.

[0010] The concrete slit tension member according to the present invention is such that an adhesive is applied to the tension member, or an adhesive is applied to or filled in the slit hole, or both methods are used so that the tension member and the slit hole are adhered and fitted to each other. The adhesive is a thermosetting resin or a thermoplastic resin and is woven into the tension member.

[0011] The concrete slit tension member according to the present invention is a non-twisted or twisted fiber bundle formed by bundling a predetermined number of high Young's modulus filament yarns and connecting them with weft yarns to form a strip shape, and a certain amount of thermosetting resin or thermoplastic resin is impregnated into the fibers and woven into the tension member.

[0012] The concrete slit tension member according to the present invention can adjust the stress by making the tension member into multiple layers, and a certain amount of thermosetting resin or thermoplastic resin can be applied and woven between the layers of the tension member.

[0013] The concrete slit tension member according to the present invention has a groove width of the slit hole into which the tension member is inserted that is the groove width obtained by adding a clearance of 0.1 mm or more and 1 mm or less to both sides of the tension member, and the groove depth is formed within a range not exceeding the covering thickness of reinforced concrete.

[0014] In the concrete slit tension member according to the present invention, the groove depth of the slit hole into which the tension member is inserted is formed within a range in which the tension member or the tension member and the partition material do not protrude from the concrete surface.

[0015] In the concrete slit tension member according to the present invention, the tension members can be woven by intersecting them in the vertical and horizontal directions within the slit holes.

[0016] In the concrete slit tension member according to the present invention, the tension members can be engaged with each other by an adhesive within the slit holes.

Effect of the Invention

[0017] By inserting the tension member of the concrete slit tension member according to the present invention into the slit holes formed in the concrete surface layer and fitting it with the concrete, neither a fastening member nor a fixing structure is required, and the same shear strength as that of a reinforcing member can be easily added to the concrete without increasing the volume and mass of the concrete.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0019] Regarding an embodiment of the concrete slit tension member according to the present invention, the tension member is shown in detail in FIG. 1. It is a tension member 100 formed by connecting fiber bundles 1 formed of fibers and resin bundled in a predetermined number with weft threads 2. The tension member 100 can be laminated according to stress, and the two-layer tension member 3, three-layer tension member 4, and four-layer tension member 5 are examples of those formed by applying a certain amount of thermosetting resin or thermoplastic resin between the laminations of the tension member 100 and knitting them into a laminate.

[0020] Regarding an embodiment of the concrete slit tension member according to the present invention, FIG. 2 shows a form in which the tension member and the slit holes in the concrete are fitted to each other. (A) is a view of the slit holes and the tension member. It shows a form before the slit holes 8 on the upper surface, the tension member 100a on the upper surface, the slit holes 9 on the side surface, the tension member 100b on the side surface, the slit holes 10 on the bottom surface, and the tension member 100c on the bottom surface are fitted into the concrete cube 6. (B) is a view of the tension member fitted into the concrete. The slit holes 8, 9, and 10 on the upper surface, side surface, and bottom surface of the concrete vertical body 6 are formed such that the tension members 100a, 100b, and 100c on the upper surface, side surface, and bottom surface do not protrude from the concrete surface layer of the concrete vertical body 6. After applying or filling an adhesive into the slit holes, an adhesive is applied to each tension member and fitted into the concrete vertical body 6.

[0021] Regarding an embodiment of the concrete slit tension member according to the present invention, FIG. 3 shows a form in which the intersecting portion of the tension members and the intersecting slit holes in the concrete are fitted to each other. (C) is a tunnel cross-sectional view, and (D) indicates the position of the concrete curved body 7a. (D) is a diagram of a slit hole intersecting a curved surface and a tension member, showing the form before the Y-direction slit hole, the Y-direction tension member 100d, the X-direction slit hole 12, and the X-direction tension member 100e of the enlarged view 7a of the concrete curved body fit together. (E) is a diagram of the tension member fitted into the concrete. The Y-direction slit hole 11 is formed in such a range that the Y-direction tension member 100d and the partition material 13 do not protrude from the concrete surface layer of the concrete curved body 7a. The X-direction slit hole is formed in such a range that the X-direction tension member 100a does not protrude from the concrete surface layer. After applying or filling an adhesive to the slit holes in both the Y and X directions, an adhesive is applied to the tension members 100d and 100e in both the Y and X directions, and after fitting them to the concrete curved body 7a, the partition material 13 is filled for the purpose of exposure, deterioration due to fire, or aesthetics and woven.

[0022] Regarding the embodiment of the concrete slit tension member according to the present invention, FIG. 4 shows the form in which the joint portion between the tension members and the slit hole of the concrete are fitted together. (F) is a diagram of the slit hole at the joint portion. At the joint portion where the tension member 100f and the tension member 100g overlap each other, the L-direction slit hole and the R-direction slit hole are ground in parallel and crossed by offsetting the dimension of the grinding tooth thickness in either direction using the free grinding wheel 20 for grinding. The dimension 17 of the slit hole is formed to be 250 mm or more and 300 mm or less. (G) is a diagram of the tension member at the joint portion fitted into the concrete. The dimension 18 of the tension member fits within the range of the dimension 17 of the slit hole. The dimension 18 of the tension members where the L-direction tension member 100f and the R-direction tension member 100g overlap each other is 200 mm or more and 250 mm or less, and a certain amount of adhesive 19 of thermosetting resin or thermoplastic resin is applied and engaged between the layers of the opposing tension members. Also, a certain amount of adhesive 19 is applied or filled in the slit hole to fit the tension member and the slit hole. This application discloses at least the following configurations. [Configuration 1] A concrete slit tension member characterized by adding tension to concrete by inserting a tension member into a slit hole formed in the concrete surface and fitting it with the concrete. [Configuration 2] The tension member and the slit hole are adhered and fitted to each other by applying an adhesive to the tension member or applying, filling, or both applying and filling the adhesive to the slit hole, and the adhesive is composed of a thermosetting resin or a thermoplastic resin. The concrete slit tension member according to Configuration 1. [Configuration 3] The tension member is formed in a strip shape by connecting untwisted or twisted fiber bundles obtained by bundling a predetermined number of high Young's modulus filament yarns with weft yarns, and impregnating the fibers with a certain amount of thermosetting resin or thermoplastic resin and then knitting them. The concrete slit tension member according to any one of Configurations 1 to 2. [Configuration 4] The stress can be adjusted by making the tension member into multiple layers, and a certain amount of thermosetting resin or thermoplastic resin can be applied and knitted between the layers. The concrete slit tension member according to any one of Configurations 1 to 3. [Configuration 5] The groove width of the slit hole into which the tension member is inserted is the groove width obtained by adding a clearance of 0.1 mm or more and 1 mm or less on both sides of the tension member, and the groove depth is formed within the range not exceeding the cover thickness of the reinforced concrete. The concrete slit tension member according to any one of Configurations 1 to 4. [Configuration 6] The groove depth of the slit hole into which the tension member is inserted is formed within the range where the tension member or the combination of the tension member and the cross member does not protrude from the concrete surface. The concrete slit tension member according to Configuration 5. [Configuration 7] The tension member can be arranged to intersect in the vertical and horizontal directions within the slit hole. The concrete slit tension member according to any one of Configurations 1 to 5. [Configuration 8] A joint of the tension member can be provided within the slit hole. The concrete slit tension member according to any one of Configurations 1 to 5.

Explanation of Symbols

[0023] 100 Tension member 1 Fiber bundle 2 Weft yarn 3 Two-layer tension member 4 Three-layer tension member 5 Four-layer tension member 100a Upper tension member 100b Side tension member 100c Bottom tension member 100d Tension member in the Y direction 100e Tension member in the X direction 100f Tension member in the L direction 100g Tension member in the R direction 6 Concrete cube 7 Concrete curved body 7a Enlargement of the concrete curved body 8 Upper slit hole 9 Side slit hole 10 Bottom slit hole 11 Slit hole in the Y direction 12 Slit hole in the X direction 13 Partition filling material 14 Concrete 15 Slit hole in the L direction 16 Slit hole in the R direction 17 Dimensions of the slit hole 18 Dimensions of the tension member 19 Adhesive 20 Grinding wheel for free grinding

Claims

**Claim 1**: A concrete slit tension member, wherein a plurality of untwisted or twisted fiber bundles, each formed by bundling a predetermined number of high Young's modulus filament yarns, are connected by weft yarns to form a strip-shaped body, and the strip-shaped bodies are laminated. It is inserted into a slit hole formed in the surface layer of the concrete body and fitted into the concrete body, thereby applying a tensile force to the concrete body. Concrete slit tension member. **Claim 2**: In the strip-shaped body, the dimension along the longitudinal direction of the filament yarn is larger than the dimension in the width direction intersecting the longitudinal direction. The concrete slit tension member according to claim 1. **Claim 3**: The laminated strip-shaped bodies are impregnated with a certain amount of thermosetting resin or thermoplastic resin between their layers. The concrete slit tension member according to claim 1. **Claim 4**: The concrete body is reinforced concrete. The width dimension of the concrete slit tension member is within the range not exceeding the covering thickness of the reinforced concrete. The concrete slit tension member according to claim 1. **Claim 5**: Form a slit hole in the surface layer of the concrete body. Insert the concrete slit tension member according to any one of claims 1 to 4 into the slit hole so as to apply a tensile force to the concrete body, and fit the concrete slit tension member into the concrete body. Reinforcement method for concrete body. **Claim 6**: The groove depth of the slit hole into which the concrete slit tension member is inserted is formed within a range where the concrete slit tension member does not protrude from the surface of the concrete body. The reinforcement method for concrete body according to claim 5. **Claim 7**: Form a first slit hole along a first direction in the surface layer of the concrete body. Form a second slit hole along a second direction orthogonal to the first direction in the surface layer of the concrete body. Here, the depth of the first slit hole is deeper than the depth of the second slit hole. Insert a first concrete slit tension member into the first slit hole. Insert a second concrete slit tension member into the second slit hole, so that the second concrete slit tension member is disposed to intersect the first concrete slit tension member in the slit hole. The reinforcement method for concrete body according to claim 5.

8. Insert a partition material into the first slit hole so as to overlap the first concrete slit tension member. The method for reinforcing a concrete body according to Claim 7.

9. Form a first slit hole along a first direction on the surface layer of the concrete body. On the surface layer of the concrete body, form a second slit hole parallel to the first slit hole and intersecting at one end of the first slit hole. Provide a joint by joining one end of the first concrete slit tension member and one end of the second concrete slit tension member to each other. Insert the first concrete slit tension member into the first slit hole, insert the joint part into the intersecting part of the first slit hole and the second slit hole, and insert the second concrete slit tension member into the second slit hole. The method for reinforcing a concrete body according to Claim 5.

10. The concrete slit tension member is inserted after applying or filling an adhesive into the slit hole, is inserted into the slit hole after applying an adhesive to the concrete slit tension member, or both. The method for reinforcing a concrete body according to Claim 5.

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