JP2011043025A - Method for reinforcing structure using tensional material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for reinforcing a structure using a tensional material, which reduces working time and costs requiring for tensioning and anchoring of the tensional material. <P>SOLUTION: The method for reinforcing the structure 10 using the tensional material 1 includes: a preparing step of preparing the tensional material 1 having a cable 2, a first pressure-bonded member 3 press-bonded to one end of the cable 2, a tension member 5 comprising the other end of the cable 2 and a second pressure-bonded member pressure-bonded to the portion where the portion for the tension member is saved from the other end; a first anchoring step of anchoring the first pressure-bonded member 3 to the structure 10; a temporary anchoring step of temporarily anchoring the tension member 5 or the second pressure-bonded member 4 to the structure 10; a tensioning step of directly tensioning the tension member 5 with a tensional device 30 to apply a predetermined tensional force to the cable 2; and a second anchoring step of anchoring the second pressure-bonded member 4 to the structure 10. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a reinforcing method for reinforcing a concrete structure, a steel structure, a suspended structure or the like with a tension material.

  Conventionally, as a method of reinforcing a structure by introducing prestress into a concrete structure such as a bridge, a method of fixing a cable to a concrete structure in a state in which the cable is tensioned with a predetermined tension is known (for example, Patent Document 1 and Patent Document 2).

  In Patent Document 1, a tension wire is connected to an anchor head that is crimped to the tip of a cable, and the tension wire is pulled by a jack unit, whereby a predetermined tension is applied to the cable, and the cable is applied with the predetermined tension. A method of fixing to a concrete structure in a tensioned state is disclosed. Specifically, a compression grip having a male thread portion on the outer periphery is pressure-bonded to the tip of the tension wire, and a female thread portion is formed in the anchor head to be engaged with the male thread portion to lock the compression grip. Has been.

  In Patent Document 2, the tip of the cable is screwed to one end of the long nut, the tip of the tension rod is screwed to the other end of the long nut, and the tension rod is pulled by the jack unit. Discloses a method of applying a predetermined tension to the cable and fixing the cable to the concrete structure.

JP-A-6-262618 JP 2007-255149 A

  In the method of Patent Document 1, it is necessary to connect a tension wire to an anchor head of a cable before performing an operation of applying tension to the cable. Also in the method of Patent Document 2, it is necessary to connect the tension rod to the long nut before performing the work of applying tension to the cable. These connections are made on site. When the tensioning and fixing work of the cable is completed, it is necessary to remove the tension wire and the tension rod. Therefore, the work time required for cable tension and fixing work increases.

  Further, in the method of Patent Document 1, it is necessary to form a male thread part on the outer periphery of the compression grip and to form a female thread part on the anchor head, which increases the cost.

  In view of the above circumstances, an object of the present invention is to provide a method for reinforcing a structure using a tensioning material that can reduce the work time and cost required for tensioning and fixing the tensioning material.

  In order to achieve the above object, a method for reinforcing a structure using a tension material according to the present invention comprises a cable, a first crimping member crimped to one end of the cable, and the other end of the cable. A preparation step of preparing a tension member having a tension part and a second pressure-bonding member crimped to the part securing the tension part from the other end, and a first step of fixing the first pressure-bonding member to the structure A fixing step, a hypothetical attachment step of attaching the tension part or the second crimping member to the structure, and a tensioning step of directly pulling the tension part by a tensioning device to give a predetermined tension to the cable. And a second fixing step of fixing the second pressure-bonding member to the structure.

  According to the method for reinforcing a structure using the tension material according to the present invention, the prepared tension material has a tension part composed of the other end portion of the cable, and in the tension step, the tension part is directly applied by the tension device. Unlike the conventional method using a tension wire or a tension rod, there is no connection work for connecting the tension wire or the tension rod to the second crimping member. Thereby, the work time required for tension and fixation of the tendon can be shortened. Further, since there is no connection work, for example, a screw part or a coupler for connecting the tension wire or the tension rod to the second pressure-bonding member becomes unnecessary, and as a result, the cost can be reduced.

  In a preferred embodiment of the present invention, between the hypothetical wearing step and the pulling step, the pulling portion is passed through a predetermined insertion hole of the ramchair, and then the ramchair is connected to the tensioning device and the structure. Intervening between.

  In the method for reinforcing a structure using the cable of the present invention, as described above, the dimension in the cable length direction of the ram chair can be reduced by the amount not using the screw portion and the coupler. This facilitates the installation and removal of the ram chair and tensioning device even when the space at the site is narrow.

  In another preferred embodiment of the present invention, in the first fixing step, the first pressure-bonding member is fixed to a first fixing tool fixed to an outer surface of the structure, and in the second fixing step, the first fixing member is fixed. The second pressure-bonding member is fixed to a second fixing tool fixed to the outer surface.

  According to this configuration, the first crimping member and the second crimping member are fixed to the outer surface of the structure via the first fixing tool and the second fixing tool, respectively. There is no need to drill holes in the structure for fixing. Thereby, the damage of the structure accompanying fixing work can be suppressed. Further, according to the above configuration, prestress acts between the outer surface of the structure where the first fixing tool is fixed and the outer surface where the second fixing tool is fixed. Can be given earthquake resistance.

  In still another preferred embodiment of the present invention, the structure has a pair of end walls facing each other, and a through hole is formed between the pair of end walls, and the first fixing is performed. In the step, after the cable is inserted into the through hole, the first crimping member is fixed to the one end wall, and in the second fixing step, the second crimping member is fixed to the other end wall. To settle.

  According to this configuration, the prestress acts in the direction in which the one end wall and the other end wall face each other, so that the structure can be provided with, for example, earthquake resistance against earthquakes.

  In still another preferred embodiment of the present invention, in the second fixing step, one or more shim plates are interposed between the second pressure-bonding member and the structure to fix the second pressure-bonding member. I do.

  According to this configuration, the tension of the cable can be finely adjusted by appropriately adjusting the number of shim plates interposed between the second crimping member and the structure.

  In still another preferred embodiment of the present invention, in the second fixing step, a fixing nut is screwed into the second pressure-bonding member and is interposed between the second pressure-bonding member and the structure. Then, the second pressure-bonding member is fixed.

  According to this configuration, by appropriately adjusting the rotation amount of the fixing nut, the second pressure-bonding member can be fixed to the structure, and the tension of the cable can be finely adjusted.

  According to the method for reinforcing a structure using the tendon according to the present invention, it is possible to reduce the working time and cost required for tensioning and fixing the tendon.

It is a side view which shows the tension material for reinforcing a structure. It is the schematic which shows the state which reinforced the bridge girder which is a structure using the tendon of FIG. It is the front view which looked at the bridge girder of FIG. 2 from the longitudinal direction. It is the schematic which shows the other state which reinforced the bridge girder which is a structure using the tendon of FIG. It is a figure for demonstrating the reinforcement method of the bridge girder which concerns on this embodiment. It is a figure for demonstrating the reinforcement method of the bridge girder which concerns on this embodiment. It is a figure for demonstrating the reinforcement method of the bridge girder which concerns on this embodiment. It is a figure for demonstrating the reinforcement method of the bridge girder which concerns on this embodiment. It is the schematic which shows the further another form which reinforced the bridge girder using the tension material of FIG. It is the schematic which shows the state which fixed the 2nd crimping | compression-bonding grip of the tension material with the fixing nut. It is the schematic which shows the state which fixed the 2nd crimping | compression-bonding grip of the tension material with the fixing nut. It is the schematic which shows the further another form which reinforced the girder bridge using the tendon of FIG. It is a schematic plan view of the girder bridge of FIG.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a side view showing a tendon used for reinforcing a structure. FIG. 2 is a schematic view showing a state in which the structure is reinforced using the tendon of FIG. As shown in FIG. 1, the tendon 1 includes a cable 2, a first crimping grip (first crimping member) 3 that is crimped to one end of the cable 2, and a tension part 5 that includes the other end of the cable 2. And a second pressure-bonding grip (second pressure-bonding member) 4 which is pressure-bonded to a portion where the tensile portion 5 is secured from the other end. The first crimping grip 3 and the second crimping grip 4 are, for example, cylindrical members.

  The structure 10 shown in FIG. 2 is a concrete bridge girder, for example. As shown in FIG. 2, the tendon 1 is installed such that the cable 2 extends along the outer surface of the bridge girder 10. Specifically, the bridge girder 10 is a bridge girder having a T-shaped cross section as shown in FIG. 3, and includes a flat plate portion 10a and leg portions 10b extending downward from the flat plate portion 10a in a substantially vertical direction. The tension material 1 is installed on each of the both side surfaces 11 of the leg portion 10b, and the cable 2 is tensioned so as to extend in the longitudinal direction and the substantially horizontal direction of the bridge girder 10 along the side surface 11 of the leg portion 10b. .

  As shown in FIG. 2, a concrete first fixing tool 12 and a second fixing tool 13 that are spaced apart in the longitudinal direction of the bridge girder 10 are fixed to each side surface 11 of the leg portion 10 b of the bridge girder 10. The first pressure-bonding grip 3 of the tendon 1 is fixed to the first fixing tool 12, and the second pressure-bonding grip 4 is fixed to the second fixing tool 13. The cable 2 of the tension material 1 is, for example, a stranded wire of PC steel. In FIG. I am nervous.

  The first fixing tool 12 has a pair of wall surfaces 12a and 12b facing each other in the longitudinal direction of the bridge girder 10, and the second fixing tool 13 has a pair of wall surfaces 13a and 13b facing each other in the longitudinal direction. The wall surface 12b of the first fixing tool 12 and the wall surface 13b of the second fixing tool 13 are opposed to each other in the longitudinal direction. The first fixing device 12 is formed with a first through portion 9a extending from the wall surface 12a to the wall surface 12b, and the second fixing device 13 is formed with a second through portion 9b extending from the wall surface 13a to the wall surface 13b. Yes.

  A first sheath tube 14 is fitted into the first through portion 9a. The first sheath tube 14 is formed integrally with a tube portion 15 through which the cable 2 is inserted and a peripheral portion at one end portion of the tube portion 15, and is positioned so as to be flush with the wall surface 12 a of the first fixing tool 12. And a bearing plate 16 having an outer surface. The first crimping grip 3 is fixed to the first end wall 12 by coming into contact with the pressure bearing plate 16 via a washer 17 in a state where the cable 2 is inserted through the pipe portion 15.

  A second sheath tube 18 having the same configuration as the first sheath tube 14 is also fitted into the second penetration portion 9b. The second crimping grip 4 is fixed to the second fixing tool 13 by abutting against the support plate 20 via the washer 21 and the shim plate 22 in a state where the cable 2 is inserted through the tube portion 19 of the second sheath tube 18. Has been. The tension force of the cable 2 can be finely adjusted by interposing one or a plurality of shim plates 22 between the second crimping grip 4 and the washer 21. In addition, a water stop member 23 for protecting the cable 2 from moisture such as rain water is interposed between the second crimping grip 4 and the shim plate 22. A water stop member may be interposed between the first crimping grip 3 and the washer 17.

  In FIG. 2, the tension portion 5 that is the other end portion of the cable 2 is not shown, but this is because the cable 2 is tensioned with a predetermined tension between the first fixing tool 12 and the second fixing tool 13. This is because the pulling portion 5 may be cut after the cutting.

  As shown in FIG. 3, the first fixing device 12 fixed to one side surface 11 and the first fixing device 12 fixed to the other side surface 11 are each provided with a leg portion 10 b by a PC steel rod 60, for example. Are connected to each other. More specifically, one first fixing tool 12, the leg 10 b and the other first fixing tool 12 are formed with unillustrated through-holes extending through the bridge girder 10 in the width direction. . Then, a PC steel rod 60 is inserted into the through hole, and fastening members 61 such as bolts are attached to both ends of the PC steel rod 60 projecting from the through hole, and tightened, whereby one first fixing tool 12 and the other first fixing tool 12 can be fixed to the corresponding side surface 11 of the leg portion 10 b and can be connected to each other with the leg portion 10 b sandwiched in the width direction of the bridge girder 10.

  As shown in FIG. 2, the first fixing device 12 is fixed at a plurality of locations (four locations in FIG. 2) at a location above the first sheath tube 14 and below the first sheath tube 14. These are fixed at a plurality of locations (4 locations in FIG. 2). In addition, although illustration is abbreviate | omitted, the 2nd fixing tool 13 fixed to one side and the 2nd fixing tool 13 fixed to the other side 11 are connected mutually similarly.

  According to the tension member 1 having the above-described configuration installed in the bridge girder 10, the cable 2 is tensioned with a predetermined tension force between the first fixing tool 12 and the second fixing tool 13, and therefore, the side surface of the leg 10b. The prestress acts in a direction facing each other between a portion of the side 11 where the first fixing tool 12 is fixed and a portion of the side surface 11 where the second fixing tool 13 is fixed. This prestress reinforces the bridge girder 10 and can improve earthquake resistance, load resistance, durability, deflection performance, and the like.

  In addition, although FIG. 2 demonstrated the case where the cable 2 was strained in the substantially horizontal direction, the cable 2 was strained in a state where it was deflected by the deflectors 7 and 8, as shown in FIG. Also good. Specifically, the first fixing tool 12 and the second fixing tool 13 are fixed so that the first sheath tube 14 and the second sheath tube 18 are slightly inclined with respect to the longitudinal direction of the bridge beam 10. The cable 2 that is tensioned between the first fixing tool 12 and the second fixing tool 13 as described above is provided with a deflecting tool (deviator) 7 at two positions in the middle portion in the longitudinal direction of the bridge girder 10 (bridge girder 10a). 8 is deflected. Accordingly, the cable 2 extends obliquely from the first crimping grip 3 to one deflector 7, extends substantially horizontally between the deflectors 7, 8, and obliquely extends from the other deflector 8 to the second crimping grip 4. Yes. By tensioning the cable 2 in this manner, when an external force such as its own weight acts on the bridge girder 10, the distribution of the bending moment due to the external force and the distribution of the introduction moment due to the prestress can be made similar. Thereby, compared with the structure (FIG. 2) which tensions the whole cable 2 to a substantially horizontal direction, the more superior earthquake resistance, load resistance, durability, a bending performance, etc. can be provided to the bridge girder 10.

  Next, with reference to FIGS. 5 to 8 in addition to FIGS. 1 and 2, a reinforcing method for reinforcing the bridge girder 10 using the tendon 1 will be described.

  First, the tendon 1 shown in FIG. 1 is prepared (preparation step). In the present embodiment, “preparing the tendon 1” means transporting the tendon 1 having the configuration shown in FIG. 1 to the construction site and waiting for installation work.

  The tendon 1 is manufactured as follows before being carried into the construction site. First, one cable 2 covered with the covering material 6 is prepared. The cable 2 has a continuous configuration from one end to the other end without interruption. Next, the first crimping grip 3 is crimped to one end of the cable 2.

  Next, the second crimping grip 4 is crimped to the cable 2 while leaving the other end 5. That is, in the cable 2, the first crimping grip 3 is fixed to the tip of one side with respect to the second crimping grip 4, and the portion on the other side of the first crimping grip 4 is for pulling. It is left as a part. The crimping position of the second crimping grip 4 in the cable 2 is set so that the other end 5 of the cable 2 has a predetermined length. The predetermined length is set according to, for example, the tension of the cable 2, the length of the entire cable 2, and the size of the installation space of the tension material 1.

  Before the first crimping grip 3 and the second crimping grip 4 are crimped to the cable 2, the covering material 6 that covers the portion of the cable 2 where the first crimping grip 3 and the second crimping grip 4 are crimped is applied. Remove in advance. Moreover, the tension | pulling part 5 is exposed in the state which the tension material 1 was completed. The tension material 1 manufactured in this way is prepared.

  Next, the first crimping grip 3 on the side where the end of the cable 2 does not protrude is fixed to the first fixing tool 12 (first fixing step). In the first fixing step, first, the first crimping grip 3 is passed through the tube portion 15 of the first sheath tube 14 from the wall surface 12b side of the first fixing tool 12 and protrudes to the opposite wall surface 12a side. Then, a washer 17 is interposed between the first crimping grip 3 and the bearing plate 16 of the first sheath tube 14, and the first crimping grip 3 is brought into contact with the bearing plate 16 via the washer 17. The diameter of the first crimping grip 3 is smaller than the hole diameter of the insertion hole 16a of the bearing plate 16, but the diameter of the washer 17 is set larger than the hole diameter of the insertion hole 16a of the bearing plate 16. After the grip 3 is once fixed, the first crimping grip 3 does not enter the first sheath tube 14.

  Next, the pulling portion 5 of the cable 2 is assumed to be attached to the second fixing tool 13 by using, for example, an intermediate grip (assumed attachment) 25 (assumed attachment step). In the assumed attachment step, as shown in FIG. 5, the tension portion 5 of the cable 2 is passed through the tube portion 19 of the second sheath tube 18 of the second fixing tool 13 from the wall surface 13 b side and exposed to the wall surface 13 a side, Thereafter, the tension portion 5 is assumed to be attached with the intermediate grip 25. The intermediate grip 25 clamps the tension part 5 with a pair of clamping parts, then bolts the clamping parts together, and inserts a wedge member into the insertion hole 25a between the clamping parts, so that the tension part 5 is assumed. Can do. Further, the intermediate grip 25 abuts against the wall surface 13 a of the second fixing tool 13 through the washer 21 in a state where the tension portion 5 is assumed. The tensile portion 5 protrudes from the wall surface 13a of the second fixing tool 13 in the assumed state. In the hypothetical wearing step, the second crimping grip 4 may be presumed to be worn after the second crimping grip 4 is exposed to the wall surface 13 a side of the second fixing tool 13. Further, as shown in FIG. 4, when the cable 2 is deflected using the deflectors 7 and 8, the cable 2 is hung on the deflectors 7 and 8 before being inserted into the tube portion 19 of the second sheath tube 18. It is done.

  Next, the ram chair 27 is installed on the bearing plate 20 of the second sheath tube 18 (ram chair installation step). As shown in FIG. 6, the ram chair 27 is a member having a U-shaped cross section, and includes a support wall 28 that faces the bearing plate 20 of the second sheath tube 18. The support wall 28 is formed with an insertion hole 29 through which the tensile portion 5 of the cable 2 is inserted. In the ram chair installation step, after passing the tension portion 5 through the insertion hole 29 of the support wall 28 of the ram chair 27, the ram chair 27 is placed on the bearing plate 20 and then attached to the second fixing tool 13. In a state where the ram chair 27 is attached to the second fixing tool 13, the tip of the tension part 5 protrudes from the ram chair 27 and the other part of the tension part 5 extends in the ram chair 27. Yes.

  Next, the jack (tensioning device) 30 is installed, and the tension portion 5 is pulled by the jack 30 (a tensioning step). In the pulling step, first, as shown in FIG. 6, the pulling portion 5 protruding from the ram chair 27 is directly engaged with the grip 31 in the jack, and the jack nose portion 32 is applied to the support wall 28 of the ram chair 27. The jack 30 is brought into an operable state. And after removing the intermediate | middle grip 25, the jack nose part 32 is stroked and the tension | pulling part 5 is pulled directly. The stroke of the jack nose portion 32 is repeated until the cable 2 reaches a predetermined tension. At this time, the second pressure-bonding grip 4 passes through the tube portion 19 of the second sheath tube 18 as the pulling portion 5 is pulled, and is exposed to the wall surface 13a side of the second fixing tool 13 (FIG. 7). In addition, the jack 30 is a well-known thing generally called a strand jack. The intermediate grip 25 may be removed before the jack 30 is operated, but may be removed after the cable 2 is pulled to some extent.

  Next, the second pressure-bonding grip 4 is fixed to the second fixing tool 13 (second fixing step). In the second fixing step, as shown in FIG. 7, a shim plate 22 is mounted between the second crimping grip 4 and the washer 21 to finely adjust the tension of the cable 2. Accordingly, since the cable 2 is held with a predetermined tension force, the second crimping grip 4 abuts against the bearing plate 20 of the second sheath tube 18 via the shim plate 22 and the washer 21, and the second fixing tool 13. To be established.

  Finally, the tensile portion 5 is cut (cutting step). In the cutting step, as shown in FIG. 8, after the jack 30 and the ram chair 27 are removed, the tensile portion 5 is cut. In addition, although the protrusion part 5 can suppress a protrusion margin by cutting | disconnecting, you may leave without pulling in consideration of re-tension.

  When the above-described steps, that is, the preparation step, the first fixing step, the assumption wearing step, the ram chair installation step, the pulling step, the second fixing step, and the cutting step are completed, the tendon 1 is tensioned and fixed as shown in FIG. The bridge girder 10 is reinforced by prestress generated by the tendon 1.

  According to the reinforcing method of the bridge girder 10 using the tension material 1 described above, the tension portion 5 of the cable 2 is directly pulled by the jack 30. Therefore, unlike the conventional method using the tension wire or the tension rod, the tension wire or the tension rod is used. There is no connection work for connecting to the second crimping grip 4. Thereby, the working time required for tension and fixing of the tendon 1 can be shortened. Further, since there is no connection work, for example, a screw part or a coupler for connecting the tension wire or the tension rod to the second crimping grip 4 becomes unnecessary, and as a result, the cost can be reduced.

  In addition, as described above, the dimensions of the ram chair 27 in the cable length direction can be reduced by the amount not using the screw portion and the coupler. This facilitates the installation and removal of the ram chair 27 and the jack 30 even when the space at the site is narrow.

  Furthermore, the first crimping grip 3 and the second crimping grip 4 are fixed to the bridge girder 10 via the first fixing tool 12 and the second fixing tool 13 fixed to the leg portion 10b of the bridge girder 10, respectively. It is not necessary to form a through hole for embedding the sheath tubes 14, 18 and the like in the 10 itself. Correspondingly, damage to the bridge girder 10 can be suppressed.

  2 to 4, the tension material 1 shown in FIG. 1 has been described with respect to the case where the cable 2 is installed so as to extend in the longitudinal direction of the bridge girder 10 along the side surface (outer surface) 11 of the bridge girder 10. As shown in FIG. 9, the tendon 1 may be installed such that the cable 2 extends into the internal space 45 of the bridge girder 40. Specifically, the bridge girder 40 is a so-called box girder, and is a pair of first end wall 41 and second end wall 42 facing each other in the longitudinal direction, and the first end wall 41 and the second end wall 42. And a pair of upper and lower connection walls 43 and 44, and left and right side walls (not shown). An internal space 45 is formed by the first end wall 41, the second end wall 42, the upper connecting wall 43, the lower connecting wall 44, and the left and right side walls. The internal space 45 may be opened in the direction of the paper surface of FIG.

  The first end wall 41 is formed with a first through portion 46 extending from the internal space 45 to the outer surface 41 a of the first end wall 41, and the second end wall 42 is A second penetrating portion 47 extending to the outer surface 42a of the two end wall 42 is formed. In the present embodiment, a through hole is formed by the internal space 45, the first through portion 46 and the second through portion 47. When the bridge girder 40 is a solid body having no internal space 45, the through hole is formed from a single hole extending from the outer surface 41a of the first end wall 41 to the outer surface 42a of the second end wall 42. Composed.

  As shown in FIG. 9, the first crimping grip 3 is fixed to the first end wall 41, and the second crimping grip 4 is fixed to the second end wall 42. The cable 2 extends into the internal space 45 of the bridge girder 40, the first through-hole 46, and the second through-hole 47, and has a predetermined gap between the first end wall 41 and the second end wall 42. I'm nervous with tension.

  A first sheath tube (fixing tube) 48 is fitted into the first penetration portion 46, and a second sheath tube (fixing tube) 49 is fitted into the second penetration portion 47. The first sheath tube 48 and the second sheath tube 49 have the same configuration as the first sheath tube 14 and the second sheath tube 18 shown in FIG. The first crimping grip 3 is fixed to the first end wall 41 by coming into contact with the pressure bearing plate 50 via the washer 17 in a state where the cable 2 is inserted through the pipe portion 51. The second crimping grip 4 abuts against the second end wall 42 by contacting the pressure plate 53 via the washer 21 and the shim plate 22 with the cable 2 inserted through the tube portion 52 of the second sheath tube 49. It has been established. A water stop member 23 is interposed between the second crimping grip 4 and the shim plate 22.

  According to the tension member 1 having the above-described configuration installed in the bridge girder 40, the cable 2 is tensioned with a predetermined tension force between the first end wall 41 and the second end wall 42. Prestress acts in the direction in which the part wall 41 and the second end wall 42 face each other. The prestress reinforces the bridge girder 40, and can improve earthquake resistance, load resistance, durability, deflection performance, and the like.

  The tension material 1 shown in FIG. 9 is also installed on the bridge girder 40 according to the above-described preparation step, first fixing step, assumption wearing step, ram chair installation step, pulling step, second fixing step, and cutting step.

  However, in the first fixing step, first, the first crimping grip 3 is inserted from the inner space 45 side of the bridge girder 40 into the tube portion 51 of the first sheath tube 48, and the first crimping grip 3 is inserted through the insertion hole 50 a of the bearing plate 50. The end wall 41 is exposed to the outer surface 41a side. Then, the washer 17 is interposed between the first crimping grip 3 and the bearing plate 50 of the first sheath tube 48, and the first crimping grip 3 is brought into contact with the bearing plate 16 via the washer 17.

  In the first fixing step, the first crimping grip 3 can be inserted into the first sheath tube 48 from the outside of the bridge beam 40 and fixed to the first end wall 41. In that case, first, the second crimping grip 4 and then the cable 2 are passed through the first sheath tube 48 and extended into the internal space 45 up to a position immediately before the first crimping grip 3 in the cable 2. Then, the washer 17 is interposed between the first crimping grip 3 and the bearing plate 50 of the first sheath tube 48, and the first crimping grip 3 is brought into contact with the bearing plate 50 via the washer 17.

  In the hypothetical wearing step, first, the tension portion 5 of the cable 2 is inserted from the inner space 45 side into the tube portion 52 of the second sheath tube 49, and the second end wall is inserted through the insertion hole 53a of the bearing plate 53. 42 is exposed to the outer surface 42a side. Then, the tension portion 5 is assumed to be attached with the intermediate grip 25.

  Further, in the ram chair installation step, the ram chair 27 is installed on the pressure bearing plate 53 of the second sheath tube 49.

  Even when the tension member 1 is tensioned and fixed to the bridge girder 40 shown in FIG. 9, the work time required for tensioning and fixing the tension member 1 can be shortened, and the cost can be reduced.

  2 and 9, the other end portion of the cable 2 is configured as the tension portion 5 and the tension member 1 is installed on the bridge girders 10 and 40. However, each end portion of the cable 2 is defined as the tension portion. The tendon 1 may be installed on the bridge girders 10 and 40. In that case, the first crimping grip 3 is crimped to a part where a tensile part is secured from one end of the cable 2.

  When such a tension member 1 is installed, that is, when tension work is performed at both ends of the cable 2, the description will be made based on the example shown in FIG. The pulling part on the grip 3 side is inserted into the first sheath tube 14 of the first fixing tool 12 and then put on using the assumed wearing tool. Next, after the tensile site on the second crimping grip 4 side is inserted through the second sheath tube 18 of the second fixing tool 13, it is assumed to be attached using an assumed attachment. Next, in the ram chair installation step, after the ram chair is installed in each of the first fixing tool 12 and the second fixing tool 13, in the pulling step, the tension part on the first crimping grip 3 side and the second crimping grip 4 are arranged. A predetermined tension force is applied to the cable 2 by pulling the side tension portions alternately or simultaneously as appropriate.

  After applying a predetermined tension to the cable 2, the first crimping grip 3 and the second crimping grip 4 are permanently fixed to the first fixing tool 12 and the second fixing tool 13, respectively. Finally, the tensile site on the first crimping grip 3 side and the tensile site on the second crimping grip 4 side are cut. In addition, you may leave both the tension site | part by the side of the 1st crimping | compression-bonding grip 3, and the tension site | part by the side of the 2nd crimping | compression-bonding grip 4, without cut | disconnecting in consideration of re-tensioning.

  2 and 9, the shim plate 22 is used for fixing the second crimping grip 4. However, as shown in FIG. 10, a fixing nut 55 may be used instead of the shim plate 22. As shown in FIG. 10, a substantially cylindrical fixing sleeve 56 is integrally provided at the end of the second pressure-bonding grip 4 opposite to the tension portion 5. A screw portion is formed on the outer peripheral surface of the fixing sleeve 56. A fixing nut 55 is screwed into the threaded portion of the fixing sleeve 56.

  In the case where the fixing nut 55 is used, the fixing nut 55 is passed through the pulling portion 5 in advance before performing the assumed wearing step, and in the pulling step in which the pulling portion 5 is pulled, the second crimping grip 4 is pulled along with the pulling of the pulling portion 5. The fixing nut 55 is screwed into the fixing sleeve 56 when being exposed to the wall surface 13 a side of the second fixing tool 13 through the second sheath tube 18. The second crimping grip 4 can be fixed to the second fixing device 13 via the fixing nut 55 by appropriately rotating the fixing nut 55 while pulling the pulling portion 5 with the jack 30 and the tension of the cable 2. Can be fine-tuned.

  FIG. 11 shows a configuration in which the second crimping grip 4 is fixed using a fixing nut, as in FIG. As shown in FIG. 11, a substantially cylindrical fixing sleeve 58 is integrally provided at the end of the second pressure-bonding grip 4 on the side opposite to the tension portion 5. Similarly to the fixing sleeve 56 shown in FIG. 9, a thread portion is formed on the outer peripheral surface of the fixing sleeve 58. A fixing nut 57 is screwed into a screw portion of the fixing sleeve 58. In the example shown in FIG. 10, the fixing nut 55 is provided with an adjustment screw allowance, that is, the tension of the cable 2 is finely adjusted by the length of the fixing nut 55 in the axial direction. In the example shown in FIG. 11, an adjustment screw margin is attached to the fixing sleeve 58, that is, the tension of the cable 2 is finely adjusted by the length in the axial direction of the fixing sleeve 58. Different types of fixing nuts are used depending on the fixing portion and the rust prevention of the screw portion.

  Even in the case where the fixing nut 57 is used, the fixing nut 57 is passed through the pulling portion 5 in advance before performing the hypothetical wearing step, and in the pulling step of pulling the pulling portion 5, the second is accompanied by the pulling of the pulling portion 5. When the crimping grip 4 is passed through the second sheath tube 18 and exposed to the wall surface 13 a side of the second fixing tool 13, the fixing nut 57 is screwed into the fixing sleeve 58. Since the fixing sleeve 58 is longer than the fixing sleeve 56, the end of the fixing sleeve 58 opposite to the second crimping grip 4 extends into the sheath tube 18. The second crimping grip 4 can be fixed to the second fixing tool 13 via the fixing nut 52 by appropriately rotating the fixing nut 57 while pulling the pulling portion 5 with the jack 30 and the tension of the cable 2. Can be fine-tuned.

  As described above, the installation form of the tension member 1 described with reference to FIG. 2 and FIG. 9 applies prestress in the longitudinal direction of the structure (bridge girder 10, 40). Can also be installed so as to act in the width direction of the structure. For example, when the structure is a hollow girder bridge composed of a plurality of hollow girder made of concrete, prestress can be applied to the width direction of the hollow girder bridge by the tension material 1.

  As shown in FIGS. 12 and 13, the hollow girder bridge 80 includes a plurality of hollow girders 81 arranged in parallel in the width direction of the hollow girder bridge 80. Each hollow beam 81 has a hollow portion 82. The plurality of hollow girders 81 are formed with through holes 85 that pass through the hollow girders 81 and extend in the width direction of the hollow girder bridge 80. The through holes 85 are provided on the upper side and the lower side when viewed from the hollow portion 82. A sheath tube 83 is embedded in the through hole 85. As shown in FIG. 12, a pair of sheath tubes 83 are embedded in the vertical direction of the hollow beam 81, and are disposed at both ends in the longitudinal direction of the hollow beam 81, as shown in FIG.

  The cable 2 of the tendon 1 is inserted into each sheath tube 83, and the first crimping grip 3 of the tendon 1 is fixed to the wall surface of the hollow girder 81 on one end side (the rightmost side in FIG. 12). The second fixing grip 4 is fixed on the wall surface of the other endmost (leftmost in FIG. 12) hollow girder 81. As described above, since the plurality of hollow girders 81 are laterally tightened by the tension members 1 installed on the hollow girder bridge 80, prestress can be applied in the width direction of the hollow girder bridge 80, and a plurality of hollow girders can be applied. The girder 81 can be integrated in the width direction.

  As mentioned above, although demonstrated about the case where the tension material 1 was installed in the bridge girder 10,40,80, you may install the tension material 1 in a concrete building. In that case, for example, by tensioning the cable between opposing concrete walls on the same floor of the building, or by tensioning the cable in the diagonal direction of the concrete building on the outer wall surface of the concrete building, Prestress can be applied. Thereby, earthquake resistance, load resistance, durability, deflection performance, etc. can be imparted to the concrete building. Moreover, the outer wall, inner wall, etc. in a concrete structure can be integrated with each other.

  Moreover, although the concrete structure was illustrated in FIG. 2 and FIG. 9 as a structure in which the tension material 1 is installed, even if the tension material 1 is installed in the composite structure which consists of concrete and a steel member. Good.

  Further, the tension material 1 may be used as a reinforcing material for a steel structure, a hanging material for a suspended structure, or the like.

1 Tensile material 2 Cable 3 First crimping grip (first crimping member)
4 Second crimping grip (second crimping member)
5 Tensile part 6 Covering material 10 Bridge girder 10a Flat plate part 10b Leg part 11 Side face 12 First fixing tool 13 Second fixing tool 14 First sheath pipe 17 Washer 18 Second sheath pipe 21 Washer 22 Shim plate 25 Intermediate grip 27 Ram chair 30 jack

Claims (6)

A method of reinforcing a structure using tendon,
A cable, a first crimping member crimped to one end of the cable, a tension part composed of the other end of the cable, and a second crimping member crimped to a part securing the tension part from the other end A preparation step of preparing a tendon having
A first fixing step of fixing the first pressure-bonding member to the structure;
A hypothetical wearing step of hypothetically attaching the tension part or the second crimping member to the structure;
A tensioning step of directly pulling the tensioning portion with a tensioning device to give a predetermined tensioning force to the cable;
A second fixing step of fixing the second pressure-bonding member to the structure;
Including methods.   2. The method for reinforcing a structure using a tendon according to claim 1, wherein the tension portion is passed through a predetermined insertion hole of a ram chair between the hypothetical wearing step and the pulling step, and then the ram. A method of interposing a chair between the jack and the structure.   3. The method of reinforcing a structure using the tendon according to claim 1 or 2, wherein in the first fixing step, the first pressure-bonding member is fixed to a first fixing tool fixed to an outer surface of the structure. In the second fixing step, the second pressure-bonding member is fixed to a second fixing tool fixed to the outer surface. 3. The method of reinforcing a structure using a tendon according to claim 1 or 2, wherein the structure has a pair of end walls facing each other, and a through hole is provided between the pair of end walls. Formed,
In the first fixing step, after the cable is inserted into the through hole, the first crimping member is fixed to the one end wall;
In the second fixing step, the second pressure-bonding member is fixed to the other end wall.   3. The method of reinforcing a structure using the tendon according to claim 1, wherein, in the second fixing step, one or more shim plates are interposed between the second pressure-bonding member and the structure. And fixing the second pressure-bonding member.   3. The method for reinforcing a structure using the tendon according to claim 1, wherein, in the second fixing step, a fixing nut is screwed into the second pressure-bonding member, and the second pressure-bonding member and the structure are screwed together. A method of fixing the second pressure-bonding member by interposing it with an object.

Images