JP2540355B2 - Manufacturing method of fiber-reinforced synthetic resin prestressed concrete tension material with fixing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a fiber-reinforced synthetic resin prestressed concrete tension material with a fixing tool, which is used for prestressed concrete.

[Conventional technology]

Conventionally, as a fiber-reinforced synthetic resin prestressed concrete tension material with a fixing tool used for a prestressed concrete member, (1) an inner surface of a metal fixing sleeve and a fiber-reinforced synthetic resin prestressed concrete tension material inserted therethrough ( (Hereinafter referred to as "FRP tension material") FRP tension material with an adhesive bond type fixing tool, which is filled with an adhesive and cured between the peripheral surface of the end of the FRP tension material, and (2) inside the metal fixing sleeve. After inserting the end of the FRP tension material,
A pressure-bonding type FRP tension member with a fixing tool, in which the sleeve is compressed to reduce the diameter and the FRP tension member is pressure-bonded, (3) Rod-shaped as disclosed in JP-A-60-203762 To the end of the FRP tension material, insert a cross-shaped crack extending in the longitudinal direction of the tension material to form four divided end pieces, and extend the metal fixing spacer with the tapered hole in the sleeve diameter direction. And insert each of the divided end pieces into the tapered hole of the fixing sleeve with spacers, and insert each of the spacers between the divided end pieces to form a tapered outer surface on the divided end piece group. Then, an FRP tension member with a fixing device filled with an epoxy resin adhesive between the divided end pieces and between the tapered outer surface of the divided end piece group and the tapered hole of the fixing sleeve, (4) 60-20376
As disclosed in Japanese Patent Publication No. 3, a resin-processed reinforcing fiber is tightly wound around the end portion of the FRP tension material so as to be tapered toward the end face side of the FRP tension material and cured. A FRP tension member with a fixing tool is known in which a truncated cone-shaped engaging portion is integrally formed, and the engaging portion is fitted into a truncated cone-shaped engaging hole in a metal fixing sleeve. .

[Problems to be Solved by the Invention]

In the case of the FRP tension member with the fixing tool of the above (1), since the tension force is resisted only by the adhesive force between the sleeve and the FRP tension member, the binding force per unit length of the sleeve is weak,
Therefore, the length of the sleeve becomes extremely long. (2)
In the case of the FRP tension material with the fixing device, by increasing the compression rate of the sleeve, the binding force per unit length of the sleeve can be increased and the sleeve length can be shortened, but the FRP tension material is made of metal. Since it is significantly softer than the sleeve for use in the FRP, if the compressibility of the sleeve is made too large, a large shear force acts on the fibers of the FRP tension member, and even if a relatively small tension acts on the FRP tension member, the FRP tension member is The problem arises that the material breaks inside or at the end of the sleeve.

Further, in the case of the FRP tension member with the fixing tool of the above (3), since the structure is complicated, the joining process is complicated and the cost is high, and the cross-shaped cracks are formed at the end of the FRP tension member, There is a problem in that stress concentrates on the ends of the cracks and breaks with a relatively small tension below the yield strength of the base material. Further, in the case of the FRP tension member with the fixing tool of the above (4), the resin-treated reinforcing fiber is wound around the end portion of the FRP tension member and cured to form a truncated cone-shaped engaging portion. Therefore, the number of windings of the reinforcing fiber is remarkably increased and the production is complicated,
Moreover, it is difficult to form the truncated cone-shaped engaging portion that completely matches the truncated cone-shaped engaging hole in the sleeve by winding the reinforcing fiber. Furthermore, when the reinforcing fiber in the state where a plurality of FRP tendons are overlapped is wound, a void portion is generated between the FRP tendons, which causes a problem that a large bonding force cannot be obtained.

It is an object of the present invention to provide a method of manufacturing an FRP tension member with a fixing device, which can strongly and inexpensively bond a metal fixing sleeve and an FRP tension member by a simple means.

[Means for solving the problem]

In order to achieve the above object, the FR with the fixing device of the present invention
In the method for manufacturing the P-tension material, the adhesive layer 3 is formed by filling an adhesive between the inner peripheral surface of the metal fixing sleeve 1 and the peripheral surface of the end portion of the FRP tension material 2 inserted therein. After the adhesive layer 3 is hardened, the sleeve 1 is compressed so as to reduce the diameter, and the sleeve 1, the adhesive layer 3 and the FRP tension material 2 are pressure-bonded to each other, thereby forming an adhesive pressure bonding type. Manufactures FRP tension material with fixing device.

Further, the outer diameter of the sleeve 1 after crimping is 93 to 99% of the outer diameter of the sleeve before compression, and the sleeve 1 is compressed so that the elongation amount of the sleeve 1 after crimping is 15% or less. There is also a manufacturing method of setting the Vickers hardness of the sleeve 1 in the range of 100 to 200 Hv. The inner surface of the sleeve 1 and FR
Spacer spacers 5 may be interposed in advance with the P-tension material 2 to hold them at a predetermined space.

[Action]

According to the present invention, since the epoxy resin adhesive is injected and filled in the gap between the FRP tension member 2 and the sleeve 1, even if the adhesive is filled in the gap and the sleeve 1 is compressed, the force is even. The FRP tension material 2 is not subjected to a shearing force, and the adhesive layer 3 is cured and then the sleeve 1
Since the crimping force is applied so as to reduce the diameter, the adhesive layer 3 serves as a cushioning material, and the crimping force of the sleeve 1 is surely secured by the FRP tension material 2
Therefore, the crimping connection between the two becomes reliable.

〔Example〕

 The present invention will now be described in detail with reference to the illustrated example.

FIGS. 1 to 3 show the order of manufacturing the FRP tension member with a fixing device according to the first embodiment of the present invention, which comprises a large number of glass fibers, carbon fibers, aromatic polyamide fibers and the like. The ultrafine long fibers are impregnated with a thermosetting resin liquid such as an epoxy resin mixed with a curing agent, etc., and then the resin-impregnated long fibers are passed through a molding die and pulled out in a state of being aligned. By doing so, it is molded into a circular cross section, and then the thermosetting resin liquid is cured by heating to form the FRP tension member 2 having a circular cross section.

Next, as shown in FIG. 1, a cylindrical metal sleeve 1
An end portion of the FRP tension material 2 is inserted therein, and an epoxy resin adhesive layer 3 is injected and filled between the entire inner peripheral surface of the sleeve 1 and the peripheral surface of the FRP tension material 2. After the adhesive layer 3 is cured and the sleeve 1 and the FRP tendon 2 are adhesively bonded to each other, the sleeve 1 is compressed so that its diameter is reduced over its entire length, as shown in FIGS. 2 and 3. ,
The sleeve 1 and the FRP tension member 2 are pressure-bonded to each other via the adhesive layer 3.

When compressing the sleeve 1, the sleeve 1 after pressure bonding
So that the outer diameter d is 93 to 99% of the outer diameter D of the sleeve 1 before compression, the elongation of the sleeve 1 after compression is 15% or less, and the Vickers hardness of the sleeve 1 after compression is in the range of 100 to 200 Hv. Then, the sleeve 1 is compressed.

When the value of the outer diameter d exceeds 99% of the value of the outer diameter D, the crimping force sharply decreases and a large crimping force cannot be obtained, and the value of the outer diameter d is 93% of the value of the outer diameter D. When smaller than%,
Since the crimping force is too large and a large shearing force acts on the FRP tension material, the FRP tension material breaks with a relatively small tensile load. Therefore, it is necessary to set the value of d / D within the range of 93 to 99%.

If the Vickers hardness of the sleeve 1 after crimping is lower than 100 Hv, the sleeve is too soft and may be deformed after fixing, and the FRP tension material may shift with respect to the sleeve, and if a screw is provided in the sleeve 1, The possibility is further increased. The Vickers hardness of the sleeve after crimping is 200 Hv
If it exceeds, the rigidity of the sleeve is too high and the crimping efficiency deteriorates. Therefore, it is necessary to set the Vickers hardness of the sleeve after crimping in the range of 100 to 200 Hv.

If the amount of stretch of the sleeve after crimping exceeds 15% of the length of the sleeve before crimping, the stretch of the sleeve
A large tensile force acts on the FRP tension material, causing the FRP in the sleeve to
The tendon may break. Therefore, the amount of elongation of the sleeve after crimping must be 15% or less of the length of the sleeve before crimping.

FIGS. 4 and 5 show a second embodiment of the present invention, in which the end portions of three FRP tension members 2 are inserted into one cylindrical metal fixing sleeve 1. However, other configurations are similar to those of the first embodiment.

FIG. 6 shows a third embodiment of the present invention,
Although the screw 4 is formed on the inner surface of the metallic fixing sleeve 1, the other configurations are the same as in the case of the first embodiment.

FIG. 7 shows a fourth embodiment of the present invention,
The metal fixing sleeve 1 is formed with a tapered inner surface 6 that expands from one end portion on the intermediate side of the FRP tension member 2 toward the other end portion, but other configurations are the same as in the case of the first embodiment. .

FIG. 8 shows a fifth embodiment of the present invention,
Although the male screw 7 is provided on the outer surface of the metal fixing sleeve 1, the other structure is the same as that of the first embodiment.

FIG. 9 and FIG. 10 show a sixth embodiment of the present invention, in which a spacer 5 made of aluminum wire is wound around one cylindrical metal fixing sleeve 1. The ends of the three FRP tendons 2 are inserted, but other configurations are the same as in the case of the first embodiment.

FIG. 11 and FIG. 12 show a seventh embodiment of the present invention, in which three circular holes provided at equal intervals are provided at both ends in one cylindrical fixing sleeve 1 made of metal. A plate-shaped plastic spacer 5 having a space is fitted, and the ends of the three FRP tendons 2 are inserted through the through holes of each spacer 5, but other configurations are the same as those of the first embodiment. It is similar to the case. In the case of the seventh embodiment, the spacer 5 is easily broken when the sleeve 1 is compressed.

FIG. 13 and FIG. 14 show an eighth embodiment of the present invention, in which three through holes 8 are provided at equal angular intervals around the center line of the metallic fixing sleeve 1, and each through hole 8 is The ends of the FRP tendons 2 are inserted into the holes 8 and the adhesive layer 3 is filled, but the other configurations are the first.
This is similar to the case of the embodiment.

In the case of the sixth embodiment and the seventh embodiment, evenly spaced gaps are provided between the inner surface of the sleeve 1 and the FRP tendons 2, and the FRP tendons 2 are evenly spaced. FRP with fixing device of a certain quality due to the spacing
Tension can be manufactured.

Next, the conventional (1) fixing sleeve adhesive bonding FRP
Sample 1 (1 FRP tension material) and sample 2 (FRP tension material)
Tensile material 3), sample 3 (six FRP materials), and sample 4 (one FRP material) and sample 5 (FRP materials 3) related to the conventional (2) fixing sleeve crimp-bonded FRP materials. Book),
Sample 6 (6 FRP tendons) and Sample 7 (FRP tendons 1) for fixing sleeve adhesive pressure bonding FRP tendons of this invention
(Use this), sample 8 (use 3 FRP tendons), sample 9 (FRP
6 tension members are used), and a pull-out resistance test of the FRP tension member from the sleeve is performed.

Samples were prepared under the following conditions using extremely short sleeves to cause slippage between the FRP tendon and the sleeve during the test.

(1) Sleeve material and length of sleeve before inserting FRP tension material Material: Carbon steel for machine structure (JIS G4051 S15CK) Length: 100mm (2) Outer diameter, inside diameter and sleeve of FRP tension material before insertion Table 1 shows the outer diameter of the sleeve after the coupling.

(3) FRP tension material: Carbon fiber reinforced synthetic resin Diameter: 12.5 mm (4) Adhesive (Samples 1, 3 to 5) Epoxy resin adhesive A pull-out test was performed on each of the above samples
The results shown in the table were obtained.

As can be seen from Table 2, when pulling resistance is compared when one tension member is used, 0.81 kg / mm ^{2 for} the conventional adhesive type and 1.38 kg / mm for the conventional crimping type. ² , whereas in the case of the present invention, 2.16 kg / mm ² ,
It can be seen that a large pull-out resistance force, which is approximately equal to the sum of the pull-out resistance force of the conventional adhesive type and the pull-out resistance force of the conventional crimp type, is exhibited.

In the case of the present invention using three tendons and 6
It can be seen that also in the case of the present invention using the tension material of the book, the pull-out resistance force of about the same size as that of the invention of using the single tension material is exerted.

The required length of the fixing sleeve calculated from the test results shown in Table 2 is shown in FIG. Also from FIG. 15, it is understood that in the case of the present invention, the length of the fixing sleeve can be remarkably shortened as compared with the conventional adhesive type and pressure type. Further, in the case of the present invention, a plurality of FRP tendons can be simultaneously adhesively bonded to one fixing sleeve.

When the liquid adhesive layer 3 is used, the sleeve 1 and
From the space between the upper end of the sleeve 1 and the FRP tension material 2 with the end of the FRP tension material 2 arranged vertically and with an annular lid between the lower end of the sleeve 1 and the FRP tension material. The epoxy resin adhesive layer 3 is injected and filled.

As the FRP tension material 2, a twisted wire of FRP wire material may be used. When an FRP tension material made of twisted FRP wire is used, the spiral groove around the FRP tension material is filled with the adhesive layer 3, so that the adhesive bonding area increases and FR
The P tension member 2 is reinforced against the shearing force when the sleeve is compressed.

FIGS. 16 to 18 show a state in which an FRP tension material with a fixing tool, which is constructed by bonding one FRP tension material and a metal fixing sleeve 1 by adhesive pressure bonding, is tension-fixed by a post-tensioning method. In the case of FIG. 16, the sheath 10 and the metal anchor plate 11 located at the end of the sheath 10 are embedded in the concrete structure 9, and the FRP tension member 12 with the fixing tool is attached to the sheath 10. The sleeve 1 having a male screw on the outer periphery is inserted into the anchor plate 11, and the fixing nut 13 screwed to the male screw of the sleeve 1 is engaged with the metal anchor plate 11.

In the case of FIG. 17 and FIG. 18, FRP tendon 1 with fixing device
2 is inserted into the sheath 10, and the sleeve 1 having a cylindrical outer peripheral surface is inserted into the metal anchor plate 11;
A fixing metal fitting 14 having a tapered hole whose diameter decreases toward the anchor plate 11 is arranged so as to surround the sleeve 1 and engages with the anchor plate 11, and further between the sleeve 1 and the fixing metal fitting 14. A plurality of wedges 15 having an arcuate cross-section are press-fitted into.

〔The invention's effect〕

Since the present invention comprises the constituent elements described in the claims, it has the following effects.

An epoxy resin adhesive is injected and filled between the inner peripheral surface of the metal fixing sleeve 1 and the peripheral surface of the end portion of the fiber-reinforced synthetic resin prestressed concrete tension member 2 inserted therein. Since the adhesive layer 3 is provided, and after the adhesive layer 3 is hardened, a pressing force is applied so as to reduce the diameter of the sleeve 1, so that there is no gap between the prestressed concrete tendons 2 and the sleeve 1. 3, the force is evenly transmitted when the sleeve 1 is compressed, so that the possibility of cutting the tension member 2 of FRP which is strong against tension but weak against shearing can be reduced, and the adhesive layer 3 serves as a buffer material. The crimping force is surely transmitted to the sleeve 1 to the FRP tension member 2, and by performing such a simple operation, it is possible to easily manufacture the FRP tension member with the fixing tool having a large pullout resistance.

In addition, the outer diameter of the sleeve 1 after crimping is 93 to 99% of the outer diameter of the sleeve before compression, and the sleeve 1 is compressed so that the elongation amount of the sleeve 1 after crimping is 15% or less. By setting the Vickers hardness of the sleeve 1 in the range of 100 to 200Hv, the FRP tension material 2 with the fixing tool that does not move the FRP tension material 2 with respect to the sleeve 1 during use and has a large pull-out resistance. It can be easily manufactured.

Furthermore, by interposing a spacing spacer 5 between the sleeve 1 and the end of the FRP tension member 2,
By filling the adhesive layer 3 having a uniform thickness between the sleeve 1 and the FRP tendon 2, it is possible to manufacture a fixed quality FRP tendon with a fixing tool.

[Brief description of drawings]

FIGS. 1 to 3 show the manufacturing sequence of the FRP tension member with fixing device according to the first embodiment of the present invention.
FIG. 2 is a vertical sectional side view showing a state where an adhesive layer is provided between the sleeve and the FRP tendon, and FIG. 2 is a vertical sectional side view showing a state where the sleeve is compressed and the sleeve and the FRP tendon are crimped. 3 is a longitudinal side view showing a part of FIG. 2 in an enlarged manner. 4 is a vertical sectional front view showing a second embodiment of the present invention, FIG. 5 is a sectional view taken along the line AA of FIG. 4, and FIGS. 6 to 8 are the third embodiment to the fifth of the present invention. FIG. 9 is a vertical sectional side view showing an embodiment, FIG. 9 is a vertical sectional side view showing a sixth embodiment of the present invention, FIG. 10 is a sectional view taken along line BB of FIG. 9, and FIG. 11 is a seventh embodiment of the present invention. An example front view, FIG. 12 is a sectional view taken along the line CC of FIG. 11, and FIG. 13 is a front view showing an eighth embodiment of the present invention.
FIG. 14 is a sectional view taken along line DD of FIG. FIG. 15 is a diagram showing the required length of the fixing sleeve, FIG. 16 is a vertical sectional side view showing an example of the fixing structure of the FRP tension member with the fixing tool, and FIG. 17 is a fixing structure of the FRP tension material with the fixing device. FIG. 18 is a vertical sectional side view showing another example, and FIG. 18 is a front view thereof. In the figure, 1 is a metal fixing sleeve, 2 is a fiber reinforced synthetic resin prestressed concrete tension material, 3 is an adhesive layer, 4 is a screw, 5 is a spacing spacer, 6 is a tapered inner surface, 7 is a male screw, 8 is a Through hole, 9 is a concrete structure, 10 is a sheath, 11 is an anchor plate, 12 is a FRP tension member with a fixing tool, 13 is a fixing nut, 14 is a fixing metal fitting, 15
Is a wedge.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-203762 (JP, A) Actually opened 51-49769 (JP, U) Actually opened 62-22216 (JP, U)

Claims (3)

(57) [Claims] 1. An epoxy resin adhesive is provided between the inner peripheral surface of a metal fixing sleeve 1 and the peripheral surface of the end portion of a fiber-reinforced synthetic resin prestressed concrete tension member 2 inserted therein. Injecting and filling to provide the adhesive layer 3, and after the adhesive layer 3 is hardened, the sleeve 1 is compressed so as to reduce the diameter, and the sleeve 1, the adhesive layer 3, and the fiber-reinforced synthetic resin prestressed concrete. A method for manufacturing a prestressed concrete tension member made of fiber reinforced synthetic resin with a fixing tool, which is pressure-bonded to the tension member 2. 2. The sleeve 1 is compressed so that the outer diameter of the sleeve 1 after crimping is 93 to 99% of the outer diameter of the sleeve before compression and the elongation amount of the sleeve 1 after crimping is 15% or less. The Vickers hardness of sleeve 1 after crimping is 100-200Hv
The method for producing a prestressed concrete tension member made of fiber reinforced synthetic resin with a fixing tool according to claim 1, wherein the tension member is set within the range. 3. A fiber-reinforced synthetic material with a fixing device according to claim 2, wherein a spacer 5 is provided between the inner surface of the metal fixing sleeve 1 and the end portion of the fiber-reinforced synthetic resin prestressed concrete tension member 2. A method for manufacturing a resin prestressed concrete tendon.