Removing device and connecting method of tension material

Abstract

To provide a removing device capable of removing a resin member from a tension material, and a method for connecting the tension material.SOLUTION: A removing device comprises: a cylindrical body into which a tension material covering a wire with a resin member is inserted, and a plurality of nozzles arranged inside the cylindrical body and jetting water toward the inside of the cylindrical body, wherein the resin member is removed by water jetted from the nozzle. Preferably, the removing device includes a first nozzle and a second nozzle arranged at a position different from the first nozzle in the circumferential direction of the cylinder body.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present technology relates to a removal device that removes a resin member from a tendon that is embedded in a deck and has a plurality of wires covered with a resin member in advance, and a method for connecting a tendon. [Background technology]

[0002] In bridge decks, tendons are sometimes buried in order to prevent cracks from occurring. Prestressed concrete (PC) steel, which is made of multiple wires covered in advance with a resin material, is sometimes used as tendons. For example, when a bridge is expanded, the existing buried PC steel is connected to new tendons (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-165122 A Summary of the Invention [Problem to be solved by the invention]

[0004] To make the connection, it is necessary to remove the resin material from the existing prestressing steel.

[0005] The present disclosure has been made in consideration of the above circumstances, and has an object to provide a removal device and a connecting method for a tendon capable of removing a resin member from a tendon. [Means for solving the problem]

[0006] A removal device according to one embodiment of the present disclosure comprises a cylindrical body into which a tension material made of a wire covered with a resin material is inserted, and a number of nozzles disposed inside the cylindrical body for spraying water toward the inside of the cylindrical body, and removes the resin material with the water sprayed from the nozzles.

[0007] In a removal device according to an embodiment of the present disclosure, a tendon is inserted into a cylindrical body, and the resin material of the tendon is removed by water sprayed from a nozzle.

[0008] In a removal device according to one embodiment of the present disclosure, the multiple nozzles include a first nozzle and a second nozzle arranged at a position different from the first nozzle in the circumferential or axial direction of the cylindrical body.

[0009] In a removal device according to an embodiment of the present disclosure, the positions of the first nozzle and the second nozzle are made to differ in the circumferential direction of the cylindrical body.

[0010] In the removal device according to one embodiment of the present disclosure, the first nozzle and the second nozzle are positioned such that water jetted from one of the first nozzle and the second nozzle does not collide with the other.

[0011] In the removal device according to one embodiment of the present disclosure, water ejected from one of the first nozzle and the second nozzle does not collide with the other.

[0012] In the removal device according to one embodiment of the present disclosure, the multiple nozzles are configured to be rotatable around the axis of the cylindrical body.

[0013] In the removal device according to one embodiment of the present disclosure, the multiple nozzles remove the resin material from the tendon while rotating.

[0014] A connection method according to one embodiment of the present disclosure includes the steps of exposing a first tension member embedded in a deck slab, removing a resin component of the first tension member using the aforementioned removal device, and connecting the first tension member to a second tension member different from the first tension member.

[0015] In a connection method according to one embodiment of the present disclosure, the above-mentioned removal device is used to remove the resin member from the first tendon, and the first tendon and the second tendon are connected together. Effect of the Invention

[0016] In one embodiment of the removal device and method for connecting a tension member of the present disclosure, a tension member is inserted into a cylindrical body and the resin component of the tension member is removed by water sprayed from a nozzle, so that the tension member can be connected to other tension members. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is an explanatory diagram illustrating bridge expansion work. [Diagram 2] FIG. 2 is a cross-sectional view illustrating a tendon. [Diagram 3] FIG. 2 is a cross-sectional view showing a tension member and a removal device 1. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Diagram 5] 4 is a cross-sectional view taken along line VV in FIG. 3. [Figure 6] FIG. 11 is a process diagram illustrating a method of connecting an existing tendon to a new tendon. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The present invention will be described below with reference to the drawings showing a removal device 1 and a connecting method of a tendon according to an embodiment. FIG. 1 is an explanatory diagram for explaining the expansion work of a bridge 50. In FIG. 1, the broken line indicates a wall 54b to be removed, and the hatching indicates a bridge girder 53, an expanded part 55b of a deck 55a, and a wall 54c to be added by the expansion. The bridge 50 includes a pier 51, a support 52, the bridge girder 53, a deck 55a, and walls 54a and 54b. The support 52 is disposed on the upper surface of the pier 51. The bridge girder 53 is installed on the bridge 50 via the support 52. A deck 55a is provided on the upper side of the bridge girder 53, and walls 54a and 54b are formed on both sides of the deck 55a.

[0019] In the deck 55a, for example, PC steel is embedded as the tendon 40. FIG. 2 is a cross-sectional view showing the tendon 40. The tendon 40 includes a plurality of wires 41, a resin member 42, and a covering portion 43. The wires 41 are made of metal. The plurality of wires 41 are twisted. The resin member 42 covers the periphery of the twisted plurality of wires 41. The resin member 42 is made of, for example, an epoxy resin material. The covering portion 43 is provided around the resin member 42. The covering portion 43 is made of, for example, a polyethylene material. A part of the resin member 42 protrudes radially outward and forms a rib 44 together with the covering portion 43. The tendon 40 is a product in which the wires 41 are covered in advance by the resin member 42 and the resin member 42 is covered by the covering portion 43, i.e., a pregrouted steel material.

[0020] When expanding the bridge 50, for example, one wall 54b (see the broken line in FIG. 1) is removed. Also, a part of the deck 55a close to the removed wall 54b is cut to expose the tendons 40 embedded in the deck 55a. Workers remove the resin member 42 from the tendons 40.

[0021] Fig. 3 is a cross-sectional view showing the tendon 40 and the removal device 1, Fig. 4 is a cross-sectional view taken along line IV-IV in Fig. 3, and Fig. 5 is a cross-sectional view taken along line VV in Fig. 3. The resin member 42 is removed by the removal device 1. The removal device 1 is a gun-shaped water jet device. The removal device 1 includes a barrel 2, a grip 3, a trigger 4, a case 10, and a water pipe 20.

[0022] One end of the barrel 2 is connected to the discharge port of a pump (not shown) via a hose (not shown). A grip 3 is provided at one end of the barrel 2. A trigger 4 is provided on the grip 3. By operating the trigger 4, for example by pressing the trigger 4, a valve provided on the hose opens and water is sprayed from a nozzle described below.

[0023] A case 10 is attached to the other end of the barrel 2 via a swivel joint 5. The case 10 includes a cylindrical portion 11, a first end surface portion 12, a tube portion 17, a second end surface portion 13, a handle 14, and a drainage channel 15. A disk-shaped first end surface portion 12 is coaxially attached to one end of the cylindrical portion 11. A first opening 12a is formed in the center of the first end surface portion 12, penetrating in the axial direction. A tube portion 17 is coaxially attached to the first opening 12a. The inner diameter of the tube portion 17 and the inner diameter of the first opening 12a are approximately the same. The tube portion 17 and the cylindrical portion 11 are in communication with each other via the first opening 12a. Note that a tube portion of another shape, such as a square tube portion, may be used instead of the cylindrical portion 11.

[0024] A disk-shaped second end surface portion 13 is coaxially provided at the other end of the cylindrical portion 11. A second opening 13a is formed in the center of the second end surface portion 13, penetrating in the axial direction. The inner diameter of the second opening 13a is larger than the diameter of the tension member 40. A disk-shaped elastic member 16 is coaxially provided on one surface of the second end surface portion 13. An opening 16a is formed in the center of the elastic member 16, penetrating in the axial direction. The inner diameter of the opening 16a is approximately the same as the diameter of the tension member 40.

[0025] A drainage channel 15 is provided on the side surface of the other end of the cylindrical portion 11. The drainage channel 15 is tubular and approximately perpendicular to the cylindrical portion 11. The drainage channel 15 and the cylindrical portion 11 are connected. Water accumulated inside the cylindrical portion 11 is drained from the drainage channel 15. The drainage channel 15 is connected to, for example, a drain pump (not shown). A handle 14 is provided on the side surface of the cylindrical portion 11. An operator can hold the grip 3 and the handle 14 to perform removal work.

[0026] A water supply pipe 20 is provided inside the cylindrical portion 11 and the tube portion 17. The water supply pipe 20 includes a first water supply passage 21, a second water supply passage 22, a third water supply passage 23, a fourth water supply passage 24, and a fifth water supply passage 25. The first water supply passage 21 is disposed inside the tube portion 17. One end of the first water supply passage 21 is connected to the other end of the barrel 2 via a swivel joint 5. The first water supply passage 21 is rotatable around the axis of the tube portion 17 relative to the tube portion 17.

[0027] The second water supply passage 22 is provided in the first end surface portion 12 and extends in the radial direction of the first end surface portion 12 between the central portion and the peripheral portion of the first end surface portion 12. One end of the second water supply passage 22 is located in the central portion of the first end surface portion 12 and is connected to the other end of the first water supply passage 21.

[0028] The third water supply passage 23 is provided on the inner peripheral surface of the cylindrical portion 11 and extends in the axial direction of the cylindrical portion 11 between the first end face portion 12 and the second end face portion 13. One end of the third water supply passage 23 is located at the first end face portion 12 and is connected to the other end of the second water supply passage 22. The other end of the third water supply passage 23 is located at a position slightly away from the second end face portion 13 toward the first end face portion 12 side and protrudes toward the radial inside of the cylindrical portion 11. A plurality of first nozzles 23a are provided at the other end of the third water supply passage 23. The first nozzles 23a protrude from the other end of the third water supply passage 23 toward the radial inside of the cylindrical portion 11. The plurality of first nozzles 23a are arranged in the axial direction of the cylindrical portion 11.

[0029] The fourth water supply passage 24 is provided in the first end surface portion 12 and extends in the radial direction of the first end surface portion 12 between the center and the periphery of the first end surface portion 12. One end of the fourth water supply passage 24 is located in the center of the first end surface portion 12 and is connected to the other end of the first water supply passage 21. That is, the other end of the first water supply passage 21 is connected to the second water supply passage 22 and the fourth water supply passage 24. As shown in FIG. 4, the difference between the phase position of the second water supply passage 22 and the phase position of the fourth water supply passage 24 around the axis of the first end surface portion 12 is approximately 180 degrees. In other words, the second water supply passage 22 and the fourth water supply passage 24 extend in opposite directions from the other end of the first water supply passage 21. In the radial direction of the first end surface portion 12, that is, in a direction perpendicular to the second water supply passage 22 and the fourth water supply passage 24, the positions of the second water supply passage 22 and the fourth water supply passage 24 are slightly offset.

[0030] The fifth water supply passage 25 is provided on the inner peripheral surface of the cylindrical portion 11 and extends in the axial direction of the cylindrical portion 11 between the first end face portion 12 and the second end face portion 13. The fifth water supply passage 25 is disposed on the opposite side of the third water supply passage 23 in the radial direction of the cylindrical portion 11. One end of the fifth water supply passage 25 is located at the first end face portion 12 and is connected to the other end of the fourth water supply passage 24. The other end of the fifth water supply passage 25 is disposed at a position slightly away from the second end face portion 13 toward the first end face portion 12 side and protrudes toward the radial inside of the cylindrical portion 11. A plurality of second nozzles 25a are provided at the other end of the fifth water supply passage 25. The second nozzles 25a protrude from the other end of the fifth water supply passage 25 toward the radial inside of the cylindrical portion 11. The plurality of second nozzles 25a are arranged in the axial direction of the cylindrical portion 11.

[0031] 5, the other end of the third water supply passage 23 has a tip surface 23b. The tip surface 23b is a protruding end surface that protrudes toward the radial inside of the cylindrical portion 11 at the other end of the third water supply passage 23. The tip surface 23b has a first surface 23c that is parallel to a direction perpendicular to the second water supply passage 22 and the fourth water supply passage 24, and a second surface 23d that is inclined with respect to the first surface 23c. The first nozzle 23a is provided on the second surface 23d.

[0032] As shown in Fig. 5, the other end of the fifth water supply passage 25 has a tip surface 25b. The tip surface 25b is a protruding end surface that protrudes toward the radial inside of the cylindrical portion 11 at the other end of the fifth water supply passage 25. The tip surface 25b has a third surface 25c that is parallel to a direction perpendicular to the second water supply passage 22 and the fourth water supply passage 24, and a fourth surface 25d that is inclined with respect to the third surface 25c. The second nozzle 25a is provided on the fourth surface 25d.

[0033] A virtual line L1 perpendicular to the second surface 23d and a virtual line L2 perpendicular to the fourth surface 25d are parallel to each other and do not intersect or coincide. The first nozzle 23a is configured to spray water along the virtual line L1 perpendicular to the second surface 23d. The second nozzle 25a is configured to spray water along the virtual line L2 perpendicular to the fourth surface 25d. Therefore, the water sprayed from the first nozzle 23a and the second nozzle 25a does not directly collide with each other.

[0034] The positions of the first nozzle 23a and the second nozzle 25a are slightly offset in a direction perpendicular to the second water supply passage 22 and the fourth water supply passage 24 and perpendicular to the axial direction of the cylindrical portion 11. That is, the first nozzle 23a and the second nozzle 25a are arranged so as not to face each other in a direction parallel to the second water supply passage 22 and the fourth water supply passage 24, that is, in the radial direction of the cylindrical portion 11, and water sprayed from one of the first nozzle 23a and the second nozzle 25a does not collide with the other.

[0035] A water passage 6 is formed inside the barrel 2 and the water supply pipe 20. The water passage 6 of the barrel 2 and the water passage 6 of the water supply pipe 20 are connected via a swivel joint 5. That is, the barrel 2, the first water supply passage 21, the second water supply passage 22, and the third water supply passage 23 are connected to allow water to flow, and the barrel 2, the first water supply passage 21, the fourth water supply passage 24, and the fifth water supply passage 25 are connected to allow water to flow. The first water supply passage 21 can rotate around the axis of the pipe portion 17 relative to the pipe portion 17, so the entire water supply pipe 20 can also rotate around the axis of the case 10.

[0036] When an operator operates the trigger 4, water is discharged from the pump, the valve opens, and the water passes through the hose, the gun barrel 2, the first water supply passage 21, the second water supply passage 22, and the third water supply passage 23, and is sprayed from the first nozzle 23a. The water also passes through the first water supply passage 21, the fourth water supply passage 24, and the fifth water supply passage 25, and is sprayed from the second nozzle 25a.

[0037] As described above, the entire water pipe 20 can rotate around the axis of the case 10. As shown by the imaginary lines L1 and L2 in FIG. 5, the direction of water sprayed from the first nozzle 23a is a direction that applies a counterclockwise force to the water pipe 20, and the direction of water sprayed from the second nozzle 25a is a direction that applies a counterclockwise force to the water pipe 20. Therefore, for example, as shown by the arrows in FIG. 5, the first nozzle 23a and the second nozzle 25a rotate counterclockwise around the axis of the case 10 while spraying water. The spray directions of the first nozzle 23a and the second nozzle 25a may be designed so that the water pipe 20 rotates clockwise. When the operator releases the operation on the trigger 4, the valve closes and spraying from the first nozzle 23a and the second nozzle 25a stops.

[0038] The operator inserts the tension member 40 into the opening 16a of the elastic member 16 and the second opening 13a, and operates the trigger 4. The first nozzle 23a and the second nozzle 25a rotate counterclockwise around the axis of the case 10 while spraying water. The water hits the circumferential surface of the tension member 40, and the covering portion 43 and the resin member 42 are removed. Since the first nozzle 23a and the second nozzle 25a rotate, water is sprayed onto the entire circumferential surface of the tension member 40, and the covering portion 43 and the resin member 42 can be removed from the entire circumferential surface. The gap between the opening 16a of the elastic member 16 and the tension member 40 is small. Therefore, the amount of water leaking out from the opening 16a to the outside is limited. That is, the elastic member 16 functions as a water stop. The water accumulated in the cylindrical portion 11 is drained from the drainage channel 15.

[0039] Case 10 may be configured to be disassembled. When removed covering portion 43 or resin member 42 accumulates inside cylindrical portion 11, the removal operation can be stopped and case 10 can be disassembled to discharge covering portion 43 or resin member 42.

[0040] The worker connects the existing tension member 40 (hereinafter also referred to as 40A) from which the covering portion 43 and the resin member 42 have been removed, to a new tension member 40 (hereinafter also referred to as 40B) that is different from the existing tension member 40. The new tension member 40B has a wire 41 but does not have the covering portion 43 or the resin member 42. The existing tension member 40A corresponds to the first tension member, and the new tension member 40B corresponds to the second tension member. Figure 6 is a process diagram explaining the method of connecting the existing tension member 40A and the new tension member 40B.

[0041] For example, after intermediate fixing devices 45 are provided to existing tendons 40A, the portions of existing tendons 40A that are outside the intermediate fixing devices 45 are cut off leaving a length suitable for attaching connectors 46 (see FIG. 6A). Then, connectors 46 are attached to existing tendons 40A (see FIG. 6B).

[0042] Then, the new tendon 40B is connected to the existing tendon 40A via the connector 46. After that, concrete is poured around the connection portion between the new tendon 40B and the existing tendon 40A and around the new tendon 40B to form the expansion portion 55b of the deck 55a. Then, the new tendon 40B is tensioned by a jack and fixed by the fixing device 47 of the expansion portion 55b of the deck 55a to introduce prestress into the expansion portion 55b of the deck 55a and to integrate it with the existing deck 55a (see FIG. 6C). After tensioning is completed, the resin member 42 is injected around the connection portion between the new tendon 40B and the existing tendon 40A and around the new tendon 40B. Note that when the new tendon 40B is a pregrouted steel material, that is, when the new tendon 40B has the resin member 42, the injection of the resin member 42 around the new tendon 40B can be omitted.

[0043] In the removal device 1 and the method for connecting a tension member of the embodiment, an existing tension member 40A is inserted into a cylindrical body, and the resin material 42 of the existing tension member 40A is removed by water sprayed from the first nozzle 23a and the second nozzle 25a, so that the existing tension member 40A can be connected to a new tension member 40B.

[0044] Furthermore, the first nozzle 23a and the second nozzle 25a are positioned at different positions in the circumferential direction of the cylindrical body, so that water can be sprayed from a plurality of directions onto the existing tendon 40A, thereby removing the resin member 42 from a plurality of directions.

[0045] In addition, since the first nozzle 23a and the second nozzle 25a are not opposed to each other, it is possible to prevent the second nozzle 25a from being damaged by the water sprayed from the first nozzle 23a, and to prevent the first nozzle 23a from being damaged by the water sprayed from the second nozzle 25a.

[0046] When using a nozzle that sprays in only one direction, the worker needs to move the nozzle in the circumferential direction of the tendon 40 or rotate the tendon 40 around its axis. In this embodiment, the first nozzle 23a and the second nozzle 25a remove the resin member 42 from the tendon 40 while rotating, so that the entire resin member 42 in the circumferential direction of the tendon 40 can be removed without such movement.

[0047] Moreover, the removal device 1 can be used to remove the resin member 42 from the existing tendon 40A, and to connect the existing tendon 40A and a new tendon 40B.

[0048] The first nozzle 23a and the second nozzle 25a may be disposed at different positions in the axial direction of the cylindrical portion 11. In this case, each nozzle is disposed so that water sprayed from one of the first nozzle 23a and the second nozzle 25a does not collide with the other. The number of nozzles is not limited to two, and may be one, or three or more. Even in the case of three or more nozzles, each nozzle is disposed so that water sprayed from any one nozzle does not collide with the other nozzles.

[0049] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is intended to include all modifications within the scope of the claims and the scope equivalent to the claims. The matters described in each embodiment can be combined with each other. In addition, the independent claims and dependent claims described in the claims can be combined with each other in all combinations regardless of the citation format. Furthermore, the claims use a format (multiple claim format) in which a claim cites two or more other claims, but this is not limited to this. A format in which a multiple claim (multi-multi claim) citing at least one multiple claim may be used. [Explanation of symbols]

[0050] 1 Removal device 5 Swivel joint 10 Cases 11 Cylindrical part (tube part) 20 Water pipe 21 1st water supply channel 22 Second water supply channel 23 Third Water Channel 23a No. 1 nozzle 24 4th Water Channel 25 No. 5 Water Channel 25a No. 2 nozzle 40, 40A, 40B tendons

Claims

1. a cylindrical body into which a tendon made of a wire covered with a resin member is inserted; A plurality of nozzles are disposed inside the cylindrical body and spray water toward the inside of the cylindrical body; Equipped with A removal device for removing the resin member by using water sprayed from the nozzle.

2. The plurality of nozzles include A first nozzle; a second nozzle disposed at a position different from the first nozzle in a circumferential or axial direction of the cylindrical body; The removal device of claim 1 .

3. The first nozzle and the second nozzle are disposed so that water jetted from one of the first nozzle and the second nozzle does not collide with the other. The removal device of claim 2 .

4. The plurality of nozzles are configured to be rotatable about the axis of the cylindrical body.

4. A removal device according to any one of claims 1 to 3.

5. exposing a first tendon embedded in the deck; removing the resin member of the first tendon by a removal device according to any one of claims 1 to 3; connecting the first tendon to a second tendon different from the first tendon; Equipped Method of connecting tension members.

Images