Method for fixing FRP tensioning material and fixing structure for FRP tensioning material

Abstract

To enable a filler to be charged across entire length of a tendon insertion hole having length disallowing a shrinkage-compensating mortar to be charged.SOLUTION: A fixation method of an aramid FRP tendon 3 in a pre-stressed concrete member (1) includes the steps of injecting a partition wall filler (5) to construct a first partition wall 6A at a predetermined position from a left end 4a of a tendon insertion hole 4, injecting the partition wall filler to construct a second partition wall 6B at a predetermined position from a right end 4b of the tendon insertion hole 4, injecting a first filler (7) for fixing the FRP tendon to a precast member (2) to a first end section S1 from one end (4a) of the tendon insertion hole 4 to the first partition wall, injecting a second filler (8) to a central section S3 from the first partition wall to the second partition wall, and injecting the first filler to a second end section S2 from the other end (4b) of the tendon insertion hole 4 to the second partition wall.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a method for fixing an FRP tendon in a prestressed concrete member and a fixing structure for the FRP tendon.

Background Art

[0002] PC steel materials are sometimes used as tendons for prestressing concrete members. In precast concrete members, ducts are embedded, and PC steel materials are inserted into the ducts. After tensioning the PC steel materials, both ends are fixed with fixtures. The fixtures hold the tension of the PC steel materials by fixing both ends of the PC steel materials to the precast member. The inside of the duct may be filled with grout. By filling with grout, corrosion of the PC steel materials is prevented, and the PC steel materials are held by the concrete member through the grout. In recent years, fiber reinforced plastic (FRP) may be used as a tendon instead of metal.

[0003] Patent Document 1 discloses a method for prestressing a concrete main girder using FRP as a tendon. This method is performed by an operator in the following procedure. The concrete main girder has a duct for inserting an FRP tendon and rectangular recesses arranged near both ends of the concrete main girder and formed to communicate with the duct. Each of the two recesses opens on the upper surface of the concrete main girder. First, FRP is inserted into the duct and the recesses and tensioned. The end of the aramid FRP cannot be fixed to the precast member with a fixture such as that used for PC steel materials. Therefore, after tensioning, a filler such as cement mortar or resin mortar is injected into both recesses and the duct. The mortar filled in both recesses fixes the FRP to the concrete main girder and holds the tension of the FRP.

Prior Art Documents

Non-Patent Documents

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-133648 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Because mortar has low fluidity, even if mortar is injected into the sheath from the recessed portion, as in Patent Document 1, it is difficult to fill the entire length of the sheath with mortar. If mortar is filled only into the recessed portion, the FRP tensioning material can be fixed to the precast main girder. However, if there is a void in the center of the sheath through which the tensioning material is inserted (tensioning material insertion hole), the strength of that part will be lower than that of the ends, and there is also a risk that the FRP tensioning material will wear down due to friction with the sheath of the precast member or other FRP tensioning materials due to vibration, etc.

[0006] In view of the above background, the present invention aims to enable the filling of a filler material along the entire length of a tensioning material insertion hole in a precast member that is formed in a tensioning material insertion hole that is too short to be filled with mortar. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides a method for fixing an FRP tensioning member (3) in a prestressed concrete member (1), comprising: a step of inserting the FRP tensioning member into a tensioning member insertion hole (4) formed in a precast member (2) (Figure 3(B)); a step of tensioning the FRP tensioning member inserted into the tensioning member insertion hole (Figure 3(C)); a first injection step (Figure 4(D)) in which, with the FRP tensioning member tensioned, a partition wall filler (5) is injected at a position spaced from one end (4a) of the tensioning member insertion hole by a distance longer than the fixing length for fixing the FRP tensioning member to the precast member in order to construct a first partition wall (6A); and with the FRP tensioning member tensioned, a second partition wall (6B) is injected at a position spaced from the other end (4b) of the tensioning member insertion hole by a distance longer than the fixing length for fixing the FRP tensioning member to the precast member. The method includes a second injection step (Figure 4(D)) in which a filler material is injected; a third injection step (Figure 4(E)) in which, after the first injection step and with the FRP tensioning material under tension, a first filler material (7) for fixing the FRP tensioning material to the precast member is injected into the first end section (S1) from one end of the tensioning material insertion hole to the first partition wall; a fourth injection step (Figure 4(F)) in which, after the first and second injection steps and with the FRP tensioning material under tension, a second filler material (8) is injected into the central section (S3) of the tensioning material insertion hole from the first partition wall to the second partition wall; and a fifth injection step (Figure 4(E)) in which, after the second injection step and with the FRP tensioning material under tension, the first filler material is injected into the second end section (S2) from the other end of the tensioning material insertion hole to the second partition wall.

[0008] According to this embodiment, in tensioner insertion holes that are too long to be filled with non-shrink mortar, the filler material can be filled along their entire length. Furthermore, by constructing a partition wall using the partition wall filler material, mixing of the first filler material and the second filler material can be prevented.

[0009] In the above embodiment, the third injection step and the fifth injection step may be performed after the first injection step and the second injection step.

[0010] According to this embodiment, after constructing the first and second partition walls by injecting the partition wall filler, the first filler is injected into the first and second end sections of the tensioner insertion holes. This allows for efficient work by appropriately positioning equipment and personnel. Furthermore, it reduces material waste associated with material changes.

[0011] In the above embodiment, the fourth injection step may be performed after the third injection step and the fifth injection step.

[0012] According to this embodiment, the second filler can be injected while the FRP tensioning material is fixed to the precast member. Therefore, the second filler does not flow into the first and second end sections. Furthermore, since the first filler can be injected into the first and second end sections of the tensioning material insertion hole, and then the second filler can be injected into the central section of the tensioning material insertion hole, the work is efficient. In addition, material waste associated with switching materials can be reduced.

[0013] In the above embodiment, in the third injection step, the fourth injection step, and the fifth injection step, the first filler or the second filler may be filled from the lower side to the higher side of each section.

[0014] According to this embodiment, the filler material can be filled while pushing out the air inside the tensioner insertion hole. Therefore, it is possible to suppress the retention of air in the first end section, the second end section, and the central section of the tensioner insertion hole.

[0015] In the above embodiment, it is preferable that an inlet or outlet for the first filler is formed in the first end section near the first partition wall, and that the inlet or outlet for the first filler is formed in the second end section near the second partition wall.

[0016] According to this embodiment, the first filler can be filled without leaving any air between the first filler and the partition wall.

[0017] In the above embodiment, it is preferable that an inlet or outlet for the second filler material is formed in the central section near the first partition wall or the second partition wall.

[0018] According to this embodiment, the second filler can be filled without leaving any air between the second filler and the two partition walls.

[0019] In the above embodiment, the first filler is non-shrink mortar, the second filler is PC grout, and the filler for the partition wall may be a mortar or resin containing a thickener that has lower fluidity than the non-shrink mortar.

[0020] According to this embodiment, by using PC grout, which has higher fluidity than non-shrink mortar, the central section of the tensioning material insertion hole can be filled with PC grout over a length that cannot be filled with non-shrink mortar. Furthermore, by using mortar or resin containing a thickening agent as the filling material for the partition wall, the spread of the filling material for the partition wall toward both ends of the tensioning material insertion hole can be suppressed, and gaps can be prevented from forming at the top of both partition walls. This suppresses mixing between the non-shrink mortar and the PC grout.

[0021] Also, in order to solve the above problems, the present invention provides a fixing structure of an FRP tendon (3) in a prestressed concrete member (1), wherein the prestressed concrete member includes a precast member (2) in which a tendon insertion hole (4) is formed, the FRP tendon disposed in the tendon insertion hole, a first partition wall composed of a partition wall filling material (5) constructed at a position spaced from one end (4a) of the tendon insertion hole by a distance longer than a fixing length for fixing the FRP tendon to the precast member, a second partition wall composed of the partition wall filling material constructed at a position spaced from the other end (4b) of the tendon insertion hole by a distance longer than the fixing length, a first fixing portion (21) composed of a first filling material (7) filled in a first end portion section (S1) from the one end of the tendon insertion hole to the first partition wall for fixing both end portions of the FRP tendon to the precast member, a second fixing portion (22) composed of the first filling material filled in a second end portion section (S2) from the other end of the tendon insertion hole to the second partition wall, and a central filling portion (23) composed of a second filling material (8) filled in a central section (S3) from the first partition wall to the second partition wall of the tendon insertion hole, and the fluidity of the second filling material is higher than the fluidity of the first filling material.

[0022] According to this aspect, by filling the first filling material at both ends of the tendon insertion hole, the FRP tendon can be fixed to the precast member. Further, by filling the second filling material in the central section of the tendon insertion hole, a fixing structure body without a cavity can be constructed. Thereby, it is possible to prevent the FRP tendon from rubbing against the precast member or other FRP tendons and wearing due to vibration or the like. The partition wall constructed by the partition wall filling material can prevent the mixing of the first filling material and the second filling material. Therefore, both end portions of the FRP tendon can be reliably fixed to the precast member. Further, since the second filling material is filled in the central section of the tendon insertion hole, the filling material can be filled over the entire length of the tendon insertion hole with a small number of injection times, and the construction is easy.

Effects of the Invention

[0023] The present invention can fill a filling material over the entire length in a tendon insertion hole of a precast member in which a tendon insertion hole having a length that cannot be filled with mortar is formed.

Brief Description of the Drawings

[0024] [Figure 1] Side view of a prestressed concrete floor slab according to an embodiment [Figure 2] Enlarged cross-sectional view of both ends of a prestressed concrete floor slab [Figure 3] Explanatory drawing of a method for fixing an FRP tendon [Figure 4] Explanatory drawing of a method for fixing an FRP tendon

Modes for Carrying Out the Invention

[0025] Hereinafter, embodiments of a method for fixing an FRP tendon and a fixing structure of an FRP tendon according to the present invention will be described with reference to the drawings. In the embodiment, an example of a prestressed concrete floor slab to which a fixing structure of an aramid FRP tendon 3 is applied will be described.

[0026] FIG. 1 is a side view of a prestressed concrete floor slab 1 according to an embodiment of the present invention. The prestressed concrete floor slab 1 is constructed by connecting a plurality of precast floor slab members 2 arranged on a girder. In the figure, the precast floor slab members 2 are sequentially numbered 21, 22, 23, ···, 2 (n―1) 、2 n in order from the left. These precast floor slab members 2 may also be collectively referred to as the precast floor slab member 2. These precast floor slab members 2 are integrated by introducing prestress by the aramid FRP tendon 3, and the prestressed concrete floor slab 1 is constructed.

[0027] Figure 2 is an enlarged cross-sectional view of both ends of the prestressed concrete deck slab 1. As shown in Figure 2, each precast deck slab member 2 has tension member insertion holes 4 that extend in the direction of the bridge axis. When multiple precast deck slab members 2 are arranged in predetermined positions, these tension member insertion holes 4 become continuous in the direction of the bridge axis, forming a single tension member insertion hole 4.

[0028] A tensioned aramid FRP tensioning material 3 is placed in the tensioning material insertion hole 4. A thickening agent-containing mortar 5 is filled as a partition wall filler for constructing partition walls 6 (6A, 6B) at a distance from the left end 4a (one end) of the tensioning material insertion hole 4 by a distance longer than the fixing length L for fixing the aramid FRP tensioning material 3. In addition, a thickening agent-containing mortar 5 is filled at a distance longer than the fixing length L from the right end 4b (the other end) of the tensioning material insertion hole 4 for constructing partition walls 6. Resin may be used as the partition wall filler. If resin is used, foamed urethane can be used. By using foamed urethane as the partition wall filler, the partition wall 6 is formed to surround the entire circumference of the aramid FRP tensioning material 3, and leakage of the filler can be prevented. Hereinafter, the partition wall 6 on the left end 4a of the tensioning member insertion hole 4 will be referred to as the first partition wall 6A, and the partition wall 6 on the right end 4b of the tensioning member insertion hole 4 will be referred to as the second partition wall 6B. When referring to both the first partition wall 6A and the second partition wall 6B, they will simply be referred to as partition wall 6.

[0029] Non-shrink mortar 7 is filled in the section from the left end 4a of the tensioning member insertion hole 4 to the first partition wall 6A, and in the section from the right end of the tensioning member insertion hole 4 to the second partition wall 6B, as a first filler for fixing the aramid FRP tensioning member 3 to the precast floor slab member 2. Hereinafter, the section from the left end 4a of the tensioning member insertion hole 4 to the first partition wall 6A will be referred to as the first end section S1, and the section from the right end 4b of the tensioning member insertion hole 4 to the second partition wall 6B will be referred to as the second end section S2. The non-shrink mortar 7 filled in the first end section S1 and hardened forms a first fixing section 21 that fixes the left end of the aramid FRP tensioning member 3 to the precast floor slab member 2. The non-shrink mortar 7 filled in the second end section S2 and hardened forms a second fixing section 22 that fixes the right end of the aramid FRP tensioning member 3 to the precast floor slab member 2. The first end section S1 and the second end section S2 are longer than the anchorage length L. The section of the tension member insertion hole 4 from the left end 4a to the anchorage length L and the section from the right end 4b to the anchorage length L may be wider than the central part of the tension member insertion hole 4. At least one precast deck slab member 2 located at each end in the bridge axis direction is an anchoring deck slab member for anchoring the aramid FRP tension member 3.

[0030] In the section from the first partition wall 6A to the second partition wall 6B, PC grout 8 is filled as a second filler material to fill the void. The central filled section 23 is formed by the PC grout 8 that has been filled into this section and hardened. In its unhardened state, PC grout 8 has higher fluidity than the non-shrink mortar 7. Hereinafter, the section from the first partition wall 6A to the second partition wall 6B will be referred to as the central section S3. The filler material is injected from the lower side to the higher side of each section. That is, in this embodiment, it is injected from the left end 4a to the right end 4b of the tensioning material insertion hole 4.

[0031] Precast floor slab member 22 adjacent to precast floor slab member 21 located at the left end and precast floor slab member 2 located at the right end n Adjacent to precast floor slab member 2 (n―1)The tensioning member insertion holes 4 of the precast slab member 2 are provided with mortar injectors 18 and 19 containing a thickening agent. In addition, a non-shrink mortar injector 9, a non-shrink mortar outlet 11, a PC grout injector 10, and a PC grout outlet 12 are provided. Hereinafter, the non-shrink mortar injector 9 and the PC grout injector 10 will simply be referred to as filler injectors. The mortar injectors 18 and 19 containing the thickening agent and the filler injectors (9 and 10) may be collectively referred to as injectors. The non-shrink mortar outlet 11 and the PC grout outlet 12 will simply be referred to as outlets. The tensioning member insertion holes 4 of the precast slab member 2 may be formed by a sheath, and the injectors and outlets may be provided on a coupler connecting the sheaths. (n―2) The tensioning material insertion hole 4 may be provided with an auxiliary inlet and outlet.

[0032] The inlet extends downward from the lower side of the tensioning member insertion hole 4 to the underside of the precast slab member 2. The outlet curves from the upper side of the tensioning member insertion hole 4 of the precast slab member 2 to the underside of the precast slab member 2. Since the inlet and outlet open on the underside of the precast slab member 2 and there are no openings on the upper side, the risk of deterioration factors entering from the road surface is avoided.

[0033] The thickening agent-containing mortar injection port 18 is located at a distance from the left end 4a of the tensioning material insertion hole 4 that is longer than the anchorage length L. The PC grout injection port 10 is located at the left end of the central section S3. Furthermore, the non-shrink mortar discharge port 11 is located at the right end of the first end section S1. The PC grout injection port 10 and the non-shrink mortar discharge port 11 are located at a distance from the left end 4a of the tensioning material insertion hole 4 that is longer than the anchorage length L.

[0034] The mortar injection port 19 containing the thickener is located at a distance from the right end 4b of the tensioning material insertion hole 4 that is longer than the anchorage length L. The PC grout discharge port 12 is located at the right end of the central section S3. Furthermore, the non-shrink mortar injection port 9 is located at the left end of the second end section S2. The non-shrink mortar injection port 9 and the PC grout discharge port 12 are located at a distance from the right end 4b of the tensioning material insertion hole 4 that is longer than the anchorage length L.

[0035] The prestressed concrete slab 1 is constructed as described above. Next, the method for fixing the aramid FRP tensioning material 3 in the prestressed concrete slab 1 will be explained using Figures 3 and 4. The following work will be performed by workers.

[0036] As shown in Figure 3(A), multiple precast slab members 2 are placed in predetermined positions. In this state, the tension member insertion holes 4 are continuous in the direction of the bridge axis and open at the left end 4a and the right end 4b. Valves are provided at the lower ends of the filler material injection ports (9, 10) and discharge ports (11, 12) of the precast slab members 2. From Figure 3(B) onward, the valves are omitted from the illustration.

[0037] As shown in Figure 3(B), aramid FRP tensioning members 3 are inserted into tensioning member insertion holes 4 that are continuous in the direction of the bridge axis. After inserting the aramid FRP tensioning members 3, the aramid FRP tensioning members 3 are tensioned using a tensioning device 13, as shown in Figure 3(C). A jack or the like may be used as the tensioning device 13. After the aramid FRP tensioning members 3 have been tensioned, an injection hose 14 is provided at the left end 4a of the tensioning member insertion hole 4, and a discharge hose 15 is provided at the right end 4b of the tensioning member insertion hole 4.

[0038] As shown in Figure 4(D), with the aramid FRP tensioning material 3 tensioned by the tensioning device 13, the thickening agent-containing mortar 5 is injected through the thickening agent-containing mortar injection ports 18 and 19. During the injection of the thickening agent-containing mortar 5, the valves of the filler injection ports (9, 10) and discharge ports (11, 12) located near the thickening agent-containing mortar injection ports 18 and 19 are kept open. The amount of thickening agent-containing mortar 5 injected is sufficient to completely fill the space from the thickening agent-containing mortar injection ports 18 and 19 to the top of the tensioning material insertion holes 4. Alternatively, an additional injection port for the thickening agent-containing mortar 5 may be added, and the thickening agent-containing mortar 5 may be injected into the tensioning material insertion holes 4 from the top and bottom of the precast floor slab member 2. After the injection of the thickening agent-containing mortar 5, the valves are closed to allow the thickening agent-containing mortar 5 to harden.

[0039] As shown in Figure 4(E), after the thickener-containing mortar 5 has hardened, non-shrink mortar 7 is injected from the injection hose 14 to fill the first end section S1 with non-shrink mortar 7. During the injection of non-shrink mortar 7, the valve of the non-shrink mortar outlet 11 is kept open. After confirmation that the non-shrink mortar 7 is being discharged from the non-shrink mortar outlet 11, the valve is closed to stop the injection of non-shrink mortar 7. Non-shrink mortar 7 is also injected from the non-shrink mortar injection port 9 to fill the second end section S2 with non-shrink mortar 7. After confirmation that the non-shrink mortar 7 is being discharged from the discharge hose 15 located at the right end 4b of the tensioning material insertion hole 4, the injection of non-shrink mortar 7 is stopped. The non-shrink mortar injection work in the first end section S1 and the non-shrink mortar injection work in the second end section S2 may be started in either order. After the non-shrink mortar 7 has been injected into both sections, the non-shrink mortar 7 is allowed to harden.

[0040] As shown in Figure 4(F), after the injection of the non-shrink mortar 7, PC grout 8 is injected from the PC grout injection port 10 to fill the central section S3 with PC grout 8. During the injection of PC grout 8, the valve provided at the PC grout discharge port 12 is kept open. After confirmation that PC grout 8 has been discharged from the PC grout discharge port 12, the valve is closed to stop the injection of PC grout 8.

[0041] After the process shown in Figure 4(E), the non-shrink mortar 7 hardens, causing both ends of the aramid FRP tensioning material 3 to be positioned at both ends in the bridge axis direction. n The tensioning device 13 is then removed, and the aramid FRP tensioning material 3 exposed from both ends of the tensioning material insertion holes 4 is cut off. In addition, valves and hoses (14, 15), etc. attached to the filler material injection ports (9, 10) and discharge ports (11, 12) opening on the underside of the precast floor slab member 2 are removed. With the above steps completed, the prestressed concrete floor slab 1 is constructed.

[0042] In this way, the first partition wall 6A and the second partition wall 6B can prevent mixing of the non-shrink mortar 7 and the PC grout 8. By providing a first anchoring section 21 and a second anchoring section 22 made of non-shrink mortar 7 in the first end section S1 from the left end 4a of the tensioning material insertion hole 4 to the first partition wall 6A, and in the second end section S2 from the second partition wall 6B to the right end 4b of the tensioning material insertion hole 4, both ends of the aramid FRP tensioning material 3 can be anchored to the precast floor slab member 2. Furthermore, by providing a central filling section 23 made of PC grout 8 in the central section S3 from the first partition wall 6A to the second partition wall 6B, a prestressed concrete floor slab 1 without voids can be constructed. This structure prevents the aramid FRP tensioning material 3 from rubbing against the precast floor slab member 2 or other aramid FRP tensioning material 3 due to vibration or the like.

[0043] If the central section S3 is long and it is difficult to fill it with non-shrink mortar 7, the injection work must be carried out multiple times while moving to different locations, resulting in poor workability. In contrast, in the above embodiment, PC grout 8 is filled into the central section S3 instead of non-shrink mortar 7. PC grout 8 has higher fluidity than non-shrink mortar 7 in its uncured state. Therefore, the filler can be easily filled into the tension material insertion holes 4 over lengths that cannot be filled with non-shrink mortar 7. As a result, PC grout 8 can be easily injected into the central section S3, which is long enough that the injection work for non-shrink mortar 7 is difficult, with fewer injections, improving workability.

[0044] As shown in Figure 2, the section of the tensioning material insertion hole 4 from the left end 4a to the anchorage length L and the section from the right end 4b to the anchorage length L are wider than the central part of the tensioning material insertion hole 4. This facilitates the injection of non-shrink mortar 7.

[0045] Furthermore, in the method for fixing the aramid FRP tensioning material 3 of the embodiment, as shown in Figure 4(D), the tensioning material insertion hole 4 is clearly divided into three sections: the first end section S1, the second end section S2, and the central section S3, by constructing a partition wall 6. After constructing the partition wall 6, the injection steps shown in Figures 4(E) and 4(F) can be performed to prevent mixing of the non-shrink mortar 7 and the PC grout 8. In addition, as shown in Figure 4(E), by injecting the PC grout 8, which has higher fluidity than the non-shrink mortar 7, into the tensioning material insertion hole 4 in the central section S3, the filler material is filled into the tensioning material insertion hole 4 over a longer length compared to when the non-shrink mortar 7 is injected.

[0046] Furthermore, in the method for fixing the aramid FRP tensioning material 3 of the embodiment, after constructing the partition wall 6, non-shrink mortar 7 is injected into the first end section S1 and the second end section S2 shown in Figure 4(E), so that the non-shrink mortar 7 is filled without flowing into the central section S3. In addition, equipment and personnel can be appropriately positioned to work efficiently, and waste of materials due to material changes can be reduced.

[0047] Furthermore, in the method for fixing the aramid FRP tensioning material 3 of the embodiment, by injecting PC grout 8 into the central section S3 shown in Figure 4(F), the PC grout 8 is filled without flowing into the first end section S1 and the second end section S2. In addition, material waste associated with material switching can be reduced.

[0048] As shown in Figures 4(E) and 4(F), the filler material is injected from the lower side to the higher side of each section. This allows the filler material to be filled while pushing out the air inside the tensioner insertion hole 4. Therefore, it is possible to suppress the retention of air in the first end section S1, the second end section S2, and the central section S3 of the tensioner insertion hole 4.

[0049] As shown in Figure 4(E), a non-shrink mortar outlet 11 is formed at the right end of the first end section S1 and near the first partition wall 6A. In addition, a non-shrink mortar injection port 9 is formed at the left end of the second end section S2 and near the second partition wall 6B. This ensures that the non-shrink mortar 7 is filled without leaving any air trapped between the non-shrink mortar 7 and the partition wall 6.

[0050] As shown in Figure 4(F), a PC grout inlet 10 or PC grout outlet 12 is formed at the end of the central section S3 and near the first partition wall 6A or near the second partition wall 6B. This allows the PC grout 8 to be filled without leaving any air between the PC grout 8 and the partition wall 6.

[0051] As shown in Figure 4(D), the filler material for constructing the partition wall 6 is a thickening agent-containing mortar 5. The fluidity of the thickening agent-containing mortar 5 is lower than that of the non-shrink mortar 7. This suppresses the spread of the thickening agent-containing mortar 5 toward both ends of the tensioning material insertion hole 4, thereby preventing gaps from forming at the top of the partition wall 6. Thus, mixing of the non-shrink mortar 7 and the PC grout 8 can be suppressed.

[0052] This concludes the description of specific embodiments. However, the present invention is not limited to the above embodiments or modifications and can be broadly modified and implemented. For example, in the above embodiments, the FRP tensioning material fixing method and fixing structure according to the present invention are applied to a prestressed concrete deck slab 1, but they may also be applied to a box girder bridge. Furthermore, the specific configuration, arrangement, quantity, material, or construction procedure of each member or part can be changed as appropriate, as long as it does not depart from the spirit of the present invention. In addition, not all of the components shown in the above embodiments are necessarily essential and can be selected as appropriate. [Explanation of Symbols]

[0053] 1: Prestressed concrete slab 2: Precast floor slab members 3: Aramid FRP tensioning material 4: Tensioner insertion hole 4a: Left end (one end) 4b: Rightmost (other end) 5: Mortar containing thickener (filler for partition walls) 6: Partition wall 6A: First partition wall 6B: Second partition wall 7: Non-shrink mortar (first filler) 8: PC Grout (Second Filling Material) 21: First Fixing Section 22: Second Fixing Section 23: Central filling section L: Fixing length S1: First end section S3: Central section S2: Second end section

Claims

1. A method for fixing FRP tensioning material in a prestressed concrete member, The steps include inserting the FRP tensioning material into the tensioning material insertion hole formed in the precast member, The steps include: tensioning the FRP tensioning material inserted into the tensioning material insertion hole, With the FRP tensioning material under tension, a first injection step is performed in which a partition wall filler is injected from one end of the tensioning material insertion hole to a position longer than the fixing length for fixing the FRP tensioning material to the precast member in order to construct a first partition wall. With the FRP tensioning material under tension, a second injection step is performed in which the partition wall filler is injected at a position spaced a distance longer than the fixing length from the other end of the tensioning material insertion hole in order to construct a second partition wall. After the first injection step, with the FRP tensioning material under tension, a third injection step is performed in which a first filler material is injected into the first end section from one end of the tensioning material insertion hole to the first partition wall to fix the FRP tensioning material to the precast member. After the first injection step and the second injection step, with the FRP tensioning material under tension, a fourth injection step is performed in which a second filler material is injected into the central section of the tensioning material insertion hole from the first partition wall to the second partition wall, A method for fixing an FRP tensioning material, comprising: a fifth injection step, after the second injection step, injecting the first filler into the second end section from the other end of the tensioning material insertion hole to the second partition wall while the FRP tensioning material is tensioned.

2. In the step of tensioning the FRP tensioning material, the FRP tensioning material is tensioned using a tensioning device, The fixing method for an FRP tensioning material according to claim 1, further comprising the step of removing the tensioning device after the third injection step, the fourth injection step, and the fifth injection step.

3. The method for fixing an FRP tensioning material according to claim 1, wherein the third injection step and the fifth injection step are performed after the first injection step and the second injection step.

4. The method for fixing an FRP tensioning material according to claim 3, wherein the fourth injection step is performed after the third injection step and the fifth injection step.

5. The method for fixing an FRP tensioning material according to any one of claims 1 to 4, wherein in the third injection step, the fourth injection step, and the fifth injection step, the first filler or the second filler is filled from the lower side to the higher side of each section.

6. The method for fixing an FRP tensioning material according to claim 5, wherein an inlet or outlet for the first filling material is formed in the first end section near the first partition wall, and the inlet or outlet for the first filling material is formed in the second end section near the second partition wall.

7. The method for fixing an FRP tensioning material according to claim 5, wherein an inlet or outlet for the second filling material is formed in the central section near the first partition wall or the second partition wall.

8. The method for fixing an FRP tensioning material according to claim 1, wherein the first filler is a non-shrink mortar, the second filler is PC grout, and the filler for the partition wall is a mortar or resin containing a thickener.

9. An anchoring structure for FRP tensioning material in a prestressed concrete member, The aforementioned prestressed concrete member is A precast member with tensioning member insertion holes formed therein, The FRP tensioning material is placed in the tensioning material insertion hole, A first partition wall consisting of a partition wall filler material constructed at a distance from one end of the tensioning material insertion hole, at a distance longer than the fixing length for fixing the FRP tensioning material to the precast member, A second partition wall made of the partition wall filler material is constructed at a position spaced a distance longer than the fixing length from the other end of the tensioning material insertion hole, A first fixing section, consisting of a first filler material that is filled in the first end section from one end of the tensioning material insertion hole to the first partition wall, for fixing both ends of the FRP tensioning material to the precast member, A second fixing portion consisting of the first filling material, which is filled in the second end section from the other end of the tensioning material insertion hole to the second partition wall, It has a central filling section consisting of a second filling material that is filled in the central section of the tensioning material insertion hole from the first partition wall to the second partition wall, An anchoring structure for an FRP tensioning material, wherein the fluidity of the second filler is higher than that of the first filler.

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