JP5291051B2 - Method and apparatus for pushing in wedge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wedge stuffing method and a wedge stuffing device capable of stuffing a wedge under the force higher than a tension load applied to a PC steel using a simple structure. <P>SOLUTION: A wedge stuffing method is used for stuffing each wedge (30) that grips each of a plurality of PC steels (17) in a hole (19a) of a wedge receiving member (19) through which the PC steel is penetrated. The method includes a first step of stuffing the wedge in the hole while bringing each of the plurality of PC steels in a tension state under a first tensioning force, and a second step of restuffing the wedge corresponding to a second PC steel that is different from a first PC steel using a reaction force derived from applying a second tensioning force that is lower than the first tensioning force to the first PC steel. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a technique for pushing a wedge holding a PC steel material into a hole of a wedge receiving member.

  The fixing structure of the PC steel material is a structure for gripping the PC steel material by the fixing wedge and transmitting the tension force of the tensioned PC steel material to the PC structure. The fixing wedge holds the PC steel material by being pushed into the hole of the wedge receiving member. As a tensioning device that constitutes the fixing structure, for example, a device described in Patent Document 1 can be cited.

  As described in Patent Document 1, when the wedge is pushed using a jack, the wedge cannot be pushed into the wedge receiving member (hole) with a force larger than the tension load when the PC steel material is tensioned. Therefore, in the apparatus described in Patent Document 1, a force larger than a predetermined tension load is generated by using the pressure support member, and the wedge is pushed in.

Japanese Patent No. 4414948

  However, in the apparatus described in Patent Document 1, since a pressure support member is required, the structure of the apparatus becomes complicated, and the wedge pushing operation becomes complicated.

  Therefore, an object of the present invention is to provide a method capable of pushing the wedge with a force larger than the tension load applied to the PC steel material with a simple configuration.

  A first invention of the present application is a wedge pushing method for pushing a wedge holding each of a plurality of PC steel materials into a hole of a wedge receiving member through which each PC steel material passes. The first step of pushing the wedge into the hole in a state of being tensed with one tension, and the reaction force when a second tension smaller than the first tension is applied to the first PC steel, And a third step of pushing the wedge corresponding to the second PC steel different from the 1PC steel into the hole again.

  A second invention of the present application is a wedge pushing device for pushing a wedge holding each of a plurality of PC steel materials into a hole of a wedge receiving member through which each PC steel material passes. It has a tension jack that applies force and generates a force that pushes the wedge into the hole. The tension jack pushes the wedge into the hole in a state where each of the plurality of PC steel materials is tensioned with the first tension force, and is smaller than the first tension force with respect to the first PC steel material among the plurality of PC steel materials. The wedge corresponding to the second PC steel different from the first PC steel is pushed into the hole again using the reaction force when the second tension is applied.

  According to this invention, the force which pushes in the wedge corresponding to 2nd PC steel materials different from 1st PC steel materials can be generated using the reaction force of the 2nd tension force given to 1st PC steel materials. Thereby, it is not necessary to use the member for exclusive use for pushing in a wedge.

FIG. 3 is a schematic diagram illustrating a fixing structure in Embodiment 1 of the present invention. FIG. 3 is a side view illustrating a configuration of a fixing wedge in Embodiment 1. It is AA sectional drawing of FIG. 2A. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. In Example 1, it is a figure explaining the tension | tensile_strength work of PC steel strand. FIG. 6 is a diagram illustrating an operation of pushing the fixing wedge again in the first embodiment. FIG. 10 is a diagram illustrating an operation of pushing the fixing wedge again in the second embodiment. It is a figure which shows the structure of the jig | tool in Example 2. FIG. It is a figure which shows the structure of the jig | tool in Example 2. FIG. FIG. 10 is a diagram showing a configuration of a jig in a modification example of Example 2. It is a figure which shows the structure of the wedge pushing-in pipe in Example 3. FIG. It is a figure which shows the structure of the wedge pushing-in pipe in Example 3. FIG. It is a figure explaining the pushing-in procedure of a fixing wedge in the structure using 27 PC steel strands.

  Examples of the present invention will be described below.

  The fixing structure in this embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view showing a fixing structure used in a girder portion of a bridge. The fixing structure 1 of the present embodiment improves the durability of the spar portion 100 by transmitting the tension force (tensile load) of the PC steel stranded wire to the spar portion 100 of the bridge.

  An outer pipe (steel pipe) 11 is arranged inside the girder portion 100, and a sheath 12 is arranged inside the outer pipe 11. The sheath 12 can be formed of, for example, polyethylene (PE) resin. One end of the liner 13 is connected to one end of the sheath 12 by welding, for example.

  One end of the trumpet 14 is connected to one end of the outer tube 11, and the trumpet 14 is located on the outer peripheral surface side of the outer tube 11. Moreover, the spacer 15 is arrange | positioned between the outer peripheral surface of the outer tube | pipe 11, and the inner peripheral surface of the trumpet 14, and the spacer 15 can be comprised with rubber | gum, for example. A liner 13 is disposed inside the trumpet 14.

  The other end of the liner 13 is connected to the guide 16. A plurality of PC steel stranded wires 17 are arranged inside the liner 13 and the sheath 12. The number of the PC steel strands 17 can be set as appropriate, and it is sufficient that a predetermined tension load can be applied to the girder portion 100. In this embodiment, as the PC steel stranded wire 17, a strand in which a plurality of strands are twisted and a resin (for example, epoxy resin) layer is formed on the outer peripheral surface of the stranded wire is used. In addition, it is not restricted to the PC steel strand 17, The PC steel material of another structure can also be used.

  A spiral line 18 is disposed on the outer circumference of the liner 13 and the guide 16. A fixing block (wedge receiving member) 19 is disposed on one end side of the guide 16, and the plurality of PC steel stranded wires 17 penetrate the fixing block 19. A spacer 20 is fixed to the fixing block 19, and the spacer 20 is disposed inside the guide 16. Further, a grout cap 21 is fixed to the fixing block 19, and the grout cap 21 covers an end portion of the PC steel stranded wire 17 protruding from the fixing block 19. The space formed inside the grout cap 21 is filled with a grout material.

  In the fixing block 19, holes through which the PC steel stranded wires 17 pass are provided in the number corresponding to the number of PC steel stranded wires 17. In addition to the PC steel stranded wire 17, a fixing wedge 30 is inserted into the hole of the fixing block 19. The fixing wedges 30 are provided as many as the number of PC steel stranded wires 17 and are provided corresponding to the PC steel stranded wires 17.

  The fixing wedge 30 is used to transmit the tension (tension load) of the PC steel stranded wire 17 to the fixing block 19. As shown in FIGS. 2A and 2B, the fixing wedge 30 surrounds the outer peripheral surface of the PC steel stranded wire 17 and includes three segments 31. 2A is a diagram showing a fitting state of the fixing block 19 and the fixing wedge 30, and FIG. 2B is a cross-sectional view taken along the line AA in FIG. 2A.

  Of each segment 31, teeth formed in a concavo-convex shape are formed on a surface (inner peripheral surface) 31 a facing the outer peripheral surface of the PC steel stranded wire 17. Further, the outer peripheral surface 31 b of each segment 31 has a tapered surface inclined with respect to the longitudinal direction of the PC steel stranded wire 17.

  The hole 19 a formed in the fixing block 19 is formed in a shape along the outer peripheral surface (tapered surface) of the fixing wedge 30. For this reason, as the fixing wedge 30 enters the hole 19 a, the inner peripheral surface of the fixing wedge 30 (the inner peripheral surface 31 a of each segment 31) comes into close contact with the outer peripheral surface of the PC steel stranded wire 17. That is, the teeth formed on the inner peripheral surface 31 a of each segment 31 bite into the outer peripheral surface of the PC steel stranded wire 17.

  In the present embodiment, the fixing wedge 30 is constituted by the three segments 31, but is not limited thereto. The fixing wedge 30 may be inserted into a space formed between the outer peripheral surface of the PC steel stranded wire 17 and the hole 19a of the fixing block 19 and may have a structure capable of gripping the PC steel stranded wire 17. For example, the fixing wedge 30 can be composed of four or more segments.

  In the fixing structure 1 of the present embodiment, a device for monitoring whether a predetermined tension load is acting on the PC steel stranded wire 17 can be provided. Specifically, a load cell can be used to monitor the tension load.

  Next, the outline | summary of the operation | work which tensions the PC steel strand 17 is demonstrated.

  First, as shown in FIG. 3, a fixing wedge 30 is attached to each PC steel stranded wire 17 penetrating the fixing block 19, and the fixing wedge 30 is inserted into the hole 19 a of the fixing block 19. For example, a tapping tool 200 can be used to insert the fixing wedge 30. Since the work prior to the state shown in FIG. 3 is known, detailed description thereof is omitted. FIG. 3 shows only some (three) PC steel stranded wires 17 among the plurality of PC steel stranded wires 17 used in the fixing structure 1.

  Next, as shown in FIG. 4, the wedge pushing pipe 310 of the tension jack 300 is attached to each PC steel stranded wire 17, and the PC steel stranded wire 17 is positioned inside the wedge pushing pipe 310.

  The wedge pushing pipes 310 are provided as many as the number of PC steel stranded wires 17, and a contact portion 311 that contacts the fixing wedge 30 is provided at one end of the wedge pushing pipe 310. Since the wedge pushing pipe 310 extends in the longitudinal direction of the PC steel stranded wire 17, the pushing force against the fixing wedge 30 can be made substantially uniform in the circumferential direction of the PC steel stranded wire 17 as described later.

  The wedge pushing pipe 310 moves along the longitudinal direction of the PC steel stranded wire 17 by receiving the driving force of the first movable portion (not shown) of the tension jack 300. As will be described later, the tension jack 300 is only required to generate a force for tensioning the PC steel stranded wire 17 and a force for pushing the fixing wedge 30. For example, a hydraulic jack or an air jack can be used.

  Next, the tension jack 300 is slid in the direction approaching the fixing block 19, and the support portion 320 formed at one end of the tension jack 300 is brought into contact with the edge of the fixing block 19 as shown in FIG. 5. The support part 320 is formed in a shape along the outer peripheral surface of the fixing block 19. By bringing the support 320 into contact with the fixing block 19, the tension jack 300 can be positioned with respect to the fixing block 19.

  Here, it is preferable to make the axial core of the tension jack 300 coincide with the axial cores of the plurality of PC steel stranded wires 17. The axial core of the tension jack 300 refers to the central portion of the region where the force of the tension jack 300 is generated. Moreover, the axial core of the some PC steel strand 17 means the core part in one bundle comprised by the some PC steel strand 17. By aligning the axis of the tension jack 300 with the axis of the plurality of PC steel stranded wires 17, the tension of the plurality of PC steel stranded wires 17 can be adjusted in a well-balanced manner or fixed by the wedge pushing pipe 310 as will be described later. The wedge 30 can be pushed in efficiently.

  In the state shown in FIG. 5, the PC steel stranded wire 17 passes through the tension jack 300, and the distal end side of the PC steel stranded wire 17 protrudes from the hole 331 formed in the second movable portion 330 of the tension jack 300. ing. The holes 331 are provided as many as the number of PC steel stranded wires 17, and each hole 331 has a tapered surface. Moreover, the 2nd movable part 330 can operate | move independently from the 1st movable part mentioned above, and can move to the longitudinal direction of the PC steel strand 17.

  Next, as shown in FIGS. 6 and 7, the temporary wedge 40 is attached to the hole 331 of the second movable portion 330. For example, as described with reference to FIG. 3, the temporary wedge 40 can be inserted into the hole 331 using the hitting tool 200. Temporary wedges 40 are provided as many as the number of PC steel stranded wires 17, and can be configured similarly to the fixing wedge 30.

  After the temporary wedge 40 is inserted into the hole 331, the second movable portion 330 of the tension jack 300 is moved in the direction of the arrow D1 in FIG. Thereby, the 2nd movable part 330 pulls the PC steel strand 17 in the direction of arrow D1 via the temporary wedge 40, and the PC steel strand 17 will be in the extended state. After extending the PC steel stranded wire 17, as shown in FIG. 9, the wedge pushing pipe 310 moves the fixing wedge 30 in the direction of the arrow D2, thereby pushing the fixing wedge 30 into the hole 19a of the fixing block 19. The fixing wedge 30 can move from the position indicated by the solid line in FIG. 9 to the position indicated by the dotted line.

  After the pushing of the fixing wedge 30 into the hole 19a is completed, the second movable portion 330 of the tension jack 300 is moved in the direction of the arrow D3 in FIG. Is released. Here, the PC steel stranded wire 17 returns to the natural state from the stretched state, the inner peripheral surface of the fixing wedge 30 is in close contact with the outer peripheral surface of the PC steel stranded wire 17, and the outer peripheral surface of the fixing wedge 30 is the fixing block 19. Close to the hole 19a. As a result, the PC steel stranded wire 17 is held by the fixing wedge 30 and maintained in a predetermined tension state. That is, a predetermined tension load can be applied to the PC steel stranded wire 17.

  Here, the larger the tension load applied to the PC steel stranded wire 17, the easier the fixing wedge 30 enters the hole 19 a of the fixing block 19. In other words, the smaller the tension load applied to the PC steel stranded wire 17, the smaller the force for pushing the fixing wedge 30 into the hole 19 a, and the force for gripping the PC steel stranded wire 17 by the fixing wedge 30 may be insufficient. .

  Further, since the reaction force of the tension jack 300 when the fixing wedge 30 is pushed into the fixing block 19 is received by the PC steel stranded wire 17 through the temporary wedge 40 (see FIG. 8), the tension acting on the PC steel stranded wire 17 is applied. The fixing wedge 30 can be pushed into the hole 19a of the fixing block 19 only with a load smaller than the load. In other words, if the tension of the PC steel stranded wire 17 is insufficient, the force for pushing the fixing wedge 30 into the fixing block 19 becomes insufficient.

  In this embodiment, the fixing wedge 30 can be further pushed into the fixing block 19 in a state where a predetermined tension load is applied to the PC steel stranded wire 17 (the state shown in FIG. 10). That is, the fixing wedge 30 can be pushed in with a load larger than the load received by the fixing wedge 30 in the state shown in FIG.

  The pushing operation of the fixing wedge 30 will be described with reference to FIG. In FIG. 11, only three PC steel strands 17a to 17c are shown for ease of explanation.

  First, temporary wedges 40a and 40b are attached to two PC steel stranded wires 17a and 17b among the three PC steel stranded wires 17a to 17c. The temporary wedge 40 is not attached to the PC steel stranded wire 17c. And the predetermined load (P2) is given with respect to PC steel strands 17a and 17b by moving the 2nd movable part 330 of the tension | tensile_strength jack 300 to the direction of the arrow D1 of FIG. The direction in which the load (P2) acts is the direction in which the PC steel stranded wire 17 is extended.

  Here, the PC steel stranded wires 17a and 17b correspond to the first PC steel material in the present invention, and the PC steel stranded wire 17c corresponds to the second PC steel material in the present invention.

  The load (P2) is a force smaller than the load (P1) given in advance to the PC steel stranded wires 17a to 17c. The load (P1) is a tension force acting on each PC steel stranded wire 17 in the state shown in FIG. 10, and is a force opposite to the direction in which the load (P2) acts. Since the load (P2) is smaller than the load (P1), even if the second movable part 330 of the tension jack 300 moves, the fixing wedges 30a and 30b do not move, and the fixing wedges 30a and 30b The state of being pushed into the hole 19a is maintained.

  On the other hand, the wedge pushing pipe 310 corresponding to the PC steel stranded wire 17c among the plurality of wedge pushing pipes (pushing members) 310 provided in the tension jack 300 is in contact with the fixing wedge 30c. The wedge pushing pipe 310 corresponding to the PC steel stranded wires 17a and 17b is not in contact with the fixing wedges 30a and 30b. As a result, only the fixing wedge 30 c receives the pushing force from the wedge pushing pipe 310.

  The tension jack 300 in this embodiment can drive only an arbitrary wedge pushing pipe 310 among the plurality of wedge pushing pipes 310. That is, the plurality of wedge pushing pipes 310 can be driven independently.

  It is also possible to attach the wedge pushing pipe 310 only to the PC steel stranded wire 17c and not attach the wedge pushing pipe 310 to the other PC steel stranded wires 17a, 17b. Even in this case, only the fixing wedge 30c can be pushed in.

  When the pushing force by the wedge pushing pipe 310 is applied only to the fixing wedge 30c, the reaction force of the load (P2) applied to the temporary wedges 40a and 40b can be applied to the fixing wedge 30c. The load (P3) acting on the fixing wedge 30c is the sum (P2 × 2) of the loads acting on the temporary wedges 40a and 40b. By applying a load (P3) to the fixing wedge 30c, the fixing wedge 30c can be further pushed into the hole 19a of the fixing block 19.

  In the configuration shown in FIG. 11, the load P2 is applied to the two PC steel stranded wires 17a and 17b using the temporary wedges 40a and 40b among the three PC steel stranded wires 17a to 17c, and one PC A load P3 is applied to the fixing wedge 30c corresponding to the steel stranded wire 17c. Here, a PC steel stranded wire 17 in which neither of the loads P2 and P3 is generated may exist. That is, it is sufficient if a load (P3) can be applied to the fixing wedge 30 to be pushed in, and there may be a PC steel stranded wire 17 on which the load (P2) is not applied.

  Moreover, in the description using FIG. 11, although the load (P2) is given to the two PC steel strands 17a and 17b, any one PC steel strand (in other words, at least one PC steel strand) Only the load (P2) may be applied to the other. In this case, the load (P3) applied to the fixing wedge 30c is equal to the load (P2). Furthermore, if the load (target load) to be applied to the fixing wedge 30 is determined in advance, the load that finally acts on the fixing wedge 30 (the sum of the load P1 and the load P3 in the example shown in FIG. 11) is the target load. What is necessary is just to determine the load P3 so that it may become. The target load can be set in advance by experiments or the like as a load when the fixing wedge 30 can reliably grip the PC steel stranded wire 17.

  As shown in FIG. 11, after the pushing into the fixing wedge 30c is completed, the other fixing wedges 30a and 30b can be pushed in by a method similar to the pushing method of the fixing wedge 30c. For example, when the fixing wedge 30a is pushed in, a load (P2) may be applied to the PC steel stranded wire 17 corresponding to the fixing wedges 30b and 30c, and a load (P3) may be applied to the fixing wedge 30a. Thereby, a load (P1 + P3) larger than the tension load (P1) can be applied to all the fixing wedges 30a to 30c, and the gripping of the PC steel stranded wire 17 by the fixing wedges 30a to 30c is strengthened. Can do.

  According to this embodiment, the fixing wedge 30 is pushed into the hole 19 a of the fixing block 19 with a force larger than the tension load of the PC steel stranded wire 17 by using the tension jack 300 that tensions the plurality of PC steel stranded wires 17. Can do. That is, as compared with the apparatus described in the cited document 1, a dedicated member for pushing the fixing wedge 30 becomes unnecessary. Further, the fixing wedge 30 can be pushed into the hole 19 a of the fixing block 19 only by performing a similar operation when tensioning the plurality of PC steel stranded wires 17.

  Next, Embodiment 2 of the present invention will be described with reference to FIG. In the present embodiment, members having the same functions as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Hereinafter, differences from the first embodiment will be mainly described.

  In the tension jack 300 of the present embodiment, all the wedge push-in pipes 310 are moved together by the operation of the first movable part. That is, as described in the first embodiment, only the specific wedge push-in pipe 310 cannot be moved. In the configuration shown in FIG. 12, only the fixing wedge 30 c among the fixing wedges 30 a to 30 c is pushed into the hole 19 a of the fixing block 19.

  In this embodiment, a jig 50 is disposed between the contact portion 311 of the wedge push-in pipe 310 and the fixing wedge 30c. The jig 50 is used to transmit the pushing force from the wedge pushing pipe 310 to the fixing wedge 30c. In this embodiment, since all the wedge push-in pipes 310 move together, all the wedge push-in pipes 310 come into contact with all the fixing wedges 30a to 30c at the same time.

  Therefore, by using the jig 50, the load (P3) can be applied only to the specific fixing wedge 30c. Here, also in the present embodiment, a load (P2) acts on the PC steel stranded wires 17a and 17b via the temporary wedge 40, and the load (P3) applied to the fixing wedge 30c is the load (P2). × 2).

  13A and 13B show a configuration (an example) of the jig 50. FIG. Here, FIG. 13A shows the configuration of the jig 50 in a plane orthogonal to the longitudinal direction of the PC steel stranded wire 17c, and FIG. 13B is a side view when viewed from the direction indicated by the arrow B in FIG. 13A. .

  The jig 50 is composed of two segments 51 and 52, and these segments 51 and 52 are connected to each other. The segment 51 is formed in the shape along the outer peripheral surface of the PC steel strand 17c, and has the recessed part 51a. The segment 52 has a convex portion 52a that engages with the concave portion 51a. By configuring the jig 50 with the two segments 51 and 52, the jig 50 is attached to the PC steel strand 17 while the tension jack 300 (including the wedge push-in pipe 310) is attached to the PC steel strand 17. Can be attached to.

  On the other hand, the jig shown in FIG. 14 can also be used. The jig shown in FIG. 14 includes two segments 53 and 54, and the segment 53 has a surface along the outer peripheral surface of the three PC steel stranded wires 17a to 17c. The segment 54 can be connected to the segment 53, and the PC steel strands 17 a to 17 c are surrounded by the segments 53 and 54.

  The shape of the jig 50 is not limited to the shape described above. That is, it is only necessary to be disposed between the fixing wedge 30 and the wedge pushing pipe 310 so that the pushing force from the wedge pushing pipe 310 can be transmitted to the fixing wedge 30.

  Also in this embodiment, the same effect as that of Embodiment 1 can be obtained. Further, in this embodiment, since all the wedge push-in pipes 310 are integrally driven, the configuration of the first movable part that drives the wedge push-in pipe 310 can be simplified.

  Next, Embodiment 3 of the present invention will be described with reference to FIGS. 15A and 15B. In the present embodiment, members having the same functions as those described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Hereinafter, differences from the first and second embodiments will be mainly described.

  FIGS. 15A and 15B are diagrams showing the configuration of the contact portion 311 provided at the tip of the wedge push-in pipe 310. FIG. 15A is a view when the contact portion 311 is in the shortest state, and FIG. 15B is a view when the contact portion 311 is extended. Also in the present embodiment, as in the second embodiment, all the wedge push-in pipes 310 are moved together by the operation of the first movable portion.

  The contact portion 311 is configured by three cylindrical portions 311a to 311c, and each cylindrical portion 311a to 311c can relatively rotate about the rotation axis RA. Screw grooves are formed on the inner peripheral surfaces of the cylindrical portions 311b and 311c. Further, screw grooves that mesh with the screw grooves of the cylindrical portions 311b and 311c are formed on the outer peripheral surface of the cylindrical portion 311a. When the cylindrical portion 311a is rotated around the rotation axis RA with respect to the cylindrical portions 311b and 311c, the cylindrical portion 311a can be moved in the direction of the arrow S. That is, the length of the contact portion 311 can be increased or decreased. Moreover, rotation of the cylindrical part 311a can be prevented by rotating the cylindrical part 311b with respect to the cylindrical part 311a.

  If the contact portion 311 having the structure shown in FIGS. 15A and 15B is used, only the contact portion 311 in the specific wedge push-in pipe 310 can be extended, and only the specific wedge push-in pipe 310 can be brought into contact with the fixing wedge 30. . Specifically, in the configuration described in FIG. 11 of the first embodiment, only the wedge pushing pipe 310 corresponding to the PC steel stranded wire 17c is made longer than the other wedge pushing pipes 310 and is brought into contact with the fixing wedge 30c. be able to.

  Note that the structure for extending or contracting the wedge pushing pipe 310 is not limited to the structure described with reference to FIGS. 15A and 15B. That is, the wedge push-in pipe 310 may be composed of a plurality of members, and the wedge push-in pipe 310 may be extended or contracted by changing the engagement position of these members.

  Also in this embodiment, the same effect as that of Embodiment 1 can be obtained. Further, in the present embodiment, the contact portion 311 is constituted by three cylindrical portions 311a to 311c, and only the engagement state of the screw grooves in the cylindrical portions 311a to 311c is changed, so that the configuration of the tension jack 300 is simplified. Can do.

  In the description of Examples 1 to 3 described above, the case where three PC steel stranded wires 17 are used has been described. However, for example, when 27 PC steel stranded wires 17 are used, as shown in FIG. The fixing wedge 30 corresponding to each PC steel stranded wire 17 can be pushed in by the method described in FIG. FIG. 16 is a diagram showing the arrangement of 27 PC steel stranded wires 17 in a plane orthogonal to the longitudinal direction of the PC steel stranded wires 17.

  First, the load P3 is applied to the corresponding fixing wedge 30 for the PC steel stranded wires 17 (9 pieces) surrounded by the dotted line F1. With respect to each of the PC steel stranded wires 17 (18 pieces) not surrounded by the dotted line F1, a load (P2) is applied using the corresponding temporary wedge 40. Thereby, the reaction force of the load (P2 × 18) becomes a force acting on the fixing wedge 30. Since there are nine fixing wedges 30 to be pushed in, a load (P2 × 18/9) acts on each fixing wedge 30. Then, the load (P2) can be set so that the sum of the load (P2 × 18/9) and the load (P1) becomes the target load.

  Next, a load (P3) is applied to the corresponding fixing wedge 30 for the PC steel stranded wires 17 (9 pieces) surrounded by the one-dot chain line F2. For each of the PC steel stranded wires 17 (18 pieces) not surrounded by the one-dot chain line F2, a load (P2) is applied using the corresponding temporary wedge 40. Thereby, similarly to the case described above, only the fixing wedge 30 corresponding to the PC steel stranded wire 17 surrounded by the alternate long and short dash line F2 can be pushed in.

  By the processing described above, the fixing wedge 30 corresponding to the PC steel stranded wires 17 (15 pieces) surrounded by the dotted line F1 and the alternate long and short dash line F2 can be pushed into the fixing block 19. Next, a pressing operation is performed on the fixing wedge 30 corresponding to the PC steel stranded wire 17 not surrounded by the dotted line F1 and the alternate long and short dash line F2. Specifically, a temporary wedge 40 is used to apply a load (P2) to the PC steel stranded wires 17 (15 pieces) into which the fixing wedge 30 has been pushed. For the PC steel stranded wires 17 (12 pieces) not surrounded by the dotted line F1 and the alternate long and short dash line F2, a load (P3) is applied to the corresponding fixing wedge 30.

  Here, the reaction force of the load (P2 × 15) is the force acting on the fixing wedge 30. Since there are twelve fixing wedges 30 to be pushed in, a load (P2 × 15/12) acts on each fixing wedge 30. The load (P2) can be set so that the sum of the load (P2 × 15/12) and the load (P1) becomes the target load.

  The method described with reference to FIG. 16 is an example, and the order in which the fixing wedges 30 are pushed in can be set as appropriate.

1: Fixing structure 11: Outer tube 12: Sheath 13: Liner 14: Trumpet 15: Spacer 16: Guide 17: PC steel stranded wire (PC steel)
18: Spiral muscle 19: Fixing block (wedge receiving member)
19a: hole 20: spacer 21: grout cap 30: fixing wedge 31: wedge segment 40: temporary wedge 50: jig 100: girder part 200: hitting tool 300: tension jack 310: wedge push-in pipe (push-in member)
320: support part 330: second movable part 331: hole

Claims (7)

A wedge pushing method for pushing a wedge holding each of a plurality of PC steel materials into a hole of a wedge receiving member through which each PC steel material passes,
A first step of pushing the wedge into the hole in a state where each of the plurality of PC steel materials is tensioned with a first tension force;
Among the plurality of PC steel materials, the second PC steel material different from the first PC steel material can be used by using a reaction force when a second tension force smaller than the first tension force is applied to the first PC steel material. A second step of pushing the wedge into the hole again;
A method for pushing in a wedge, comprising:   2. The wedge pushing method according to claim 1, wherein in the second step, the wedge pushing corresponding to all the PC steel materials is performed while changing the first PC steel material and the second PC steel material.   3. The wedge pushing-in method according to claim 1, wherein the first PC steel material is any PC steel material other than the second PC steel material among the plurality of PC steel materials.   The said 1st process and the said 2nd process WHEREIN: The tension | tensile_strength of the said PC steel material and pushing in of the said wedge are performed using the same tension | tensile_strength jack, The one of Claim 1 characterized by the above-mentioned. How to push in the wedge. A wedge pushing device for pushing a wedge holding each of a plurality of PC steel materials into a hole of a wedge receiving member through which each PC steel material passes,
A tension jack that applies tension to the plurality of PC steel materials and generates a force for pushing the wedge into the hole;
The tension jack
In a state where each of the plurality of PC steel materials is tensioned with a first tension force, the wedge is pushed into the hole,
Among the plurality of PC steel materials, the second PC steel material different from the first PC steel material can be used by using a reaction force when a second tension force smaller than the first tension force is applied to the first PC steel material. Push the wedge into the hole again,
A wedge pushing device characterized by that. A push-in member connected to the tension jack and for pushing in the wedge corresponding to each PC steel;
A transmission member disposed between the wedge and the pushing member, and transmitting a force from the pushing member to the wedge;
The wedge pushing device according to claim 5, wherein: Connected to the tension jack, and having a pushing member for pushing in the wedge corresponding to each PC steel material,
6. The wedge pushing device according to claim 5, wherein a length of the pushing member is changeable.

Images