JP2005207218A - Cable protecting and fixing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To simply and efficiently display the good fixing performance on a cable by protecting the cable penetrating a deflection part in a bridge. <P>SOLUTION: A cable protecting and fixing method comprises a process for removing a coating material 52 of part 30 of a cable 3 passing through a deflection pipe 2 of a deflection part 1 The part corresponds to an abdominal pressure acting section in at least a deflection pipe 2, a process for inserting the cable 3 from which the coating material 52 is removed in the deflection pipe 2, and a process for filling an epoxy resin 7 into the deflection pipe 2 and coating at least the part 30 of the cable from which the coating material 52 is removed with the epoxy resin 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for protecting a cable that passes through a deflection portion such as a saddle structure in a bridge, a cable protection structure, a structure including the cable protection structure, and a cable fixing device.

  As a cable protection method, for example, in a sheath that encloses a PC cable and is filled with grout inside, and has a plurality of circumferential recesses on the inner peripheral surface at intervals in the tube axis direction A protective sheath for a PC cable (see Patent Document 1), which is characterized by forming a communication portion that connects the recesses, has been proposed.

Also, various cable fixing devices have been conventionally devised so as not to slide when a diagonal member such as a cable-stayed bridge penetrates the saddle portion. For example, it has a double-pipe structure consisting of an outer pipe that is buried through the support pillar of a cable-stayed bridge and an inner pipe that is loosely inserted into the outer pipe, and a cable is inserted into the inner pipe for injection filling. A deflecting member to be fixed with a material, wherein the inner surface of the main body divided into at least two parts has a tapered shape and is inserted into both end portions of the inner tube to seal a tube port around the cable; An anchor member embedded in the support column outside the both ends of the tube; and a pressing block supported and fixed to the anchor member and pressed against the end of the outer tube and the spacer from the outside. A cable-stayed bridge cable deflecting body (see Patent Document 2) and the like have been proposed.
JP 2002-81170 A JP-A-11-280021

  However, no method has been proposed to protect against damage caused by abdominal pressure in the deflecting part, with respect to the cable in which the outer cable in the box girder bridge or the diagonal member such as the cable stayed bridge penetrates the deflecting part such as the saddle part. .

  Further, regarding the cable fixing device, in various conventional methods, for example, various parts such as a flange welded to the outer tube, a spacer, a holding metal fitting, and an anchor bolt need to be used for the cable fixing device.

  For this reason, the number of parts used is increased, and it is difficult to appropriately reduce man-hours and costs. In addition, the use of a combination of many parts tends to complicate the structure of the fixing device (including the attachment structure to the deflection unit), and the working efficiency has not been improved. Therefore, for example, when the difference in tension between the cables on both sides of the deflection unit is small compared to the cable tension, it is difficult to say that the method is economical.

  On the other hand, when galvanized PC steel wire is used for the cable, if cement grout or the like is used as a filler filling the socket, the zinc contained in the cable and the cement grout may react to generate hydrogen gas. There was also. In this case, the plating film of the cable is reduced, and there is a risk of hydrogen embrittlement.

  Furthermore, in order to develop a good adhesion between the cement grout and the cable, it is necessary to take a suitable adhesion length, and when the difference in cable tension is large, the socket inner space is tapered. The cable fixing method itself is complicated and troublesome, such as increasing the size of the fixing device itself.

  Accordingly, an object of the present invention is to provide a cable protection method, a cable protection structure, and a cable protection structure that enable protection of a cable that passes through a deflection portion in a bridge, and that can easily and efficiently express good fixing performance of the cable. An object of the present invention is to provide a structure having a cable protection structure and a cable fixing device.

  The cable protection method of the present invention that solves the above problem is a protection method for a cable that passes through a deflecting portion such as a saddle structure in a bridge, and among the cables that pass through the deflecting tube in the deflecting portion, A step of removing at least the covering material corresponding to the abdominal pressure acting section in the deflection tube, a step of inserting the cable from which the covering material has been removed, the deflection tube, and an epoxy resin filling the deflection tube, A step of covering at least a portion of the cable from which the covering material has been removed with an epoxy resin (first invention).

  According to a second invention, in the first invention, the deflection tube is a single tube, and corresponds to a portion of the cable inserted through the single tube from which the covering material is removed in the abdominal pressure acting section in the deflection tube. The single pipe is filled with an epoxy resin, and at least a portion of the cable from which the covering material is removed is covered with the epoxy resin.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the curvature of the abdominal pressure acting section in the deflection tube is equal to or greater than the curvature that generates the abdominal pressure exceeding the wear resistance of the covering material, and the abrasion resistance of the epoxy resin It is characterized by being below a curvature that produces abdominal pressure that does not exceed sex.

  According to a fourth invention, in the first invention, the deflection pipe is a double pipe provided with an inner pipe through which the cable is inserted, and the epoxy resin is filled in the inner pipe. .

  According to a fifth invention, in any one of the first to fourth inventions, the bridge is a truss bridge.

  6th invention is a structure which protects the cable inserted in deflection parts, such as a saddle structure in a bridge, and removes the covering material of the part which corresponds to the abdominal pressure action section in the deflection pipe in the deflection pipe A cable protection structure, wherein the cable is inserted into the deflection tube, the deflection tube is filled with epoxy resin, and at least a portion of the cable from which the coating material has been removed is coated with the epoxy resin. It takes.

  7th invention is a structure provided with the structure which protects the cable penetrated to deflection parts, such as a saddle structure in a bridge, and is a part which corresponds to an abdominal pressure action section in the deflection pipe in the deflection pipe A cable protection structure formed by inserting the cable from which the covering material is removed into the deflection tube, filling the deflection tube with an epoxy resin, and coating at least a portion of the cable from which the covering material has been removed with the epoxy resin The structure is characterized by comprising:

  In addition, the problems disclosed by the present application and the solutions thereof will be clarified by the embodiments of the present invention and the drawings.

  ADVANTAGE OF THE INVENTION According to this invention, the protection of the cable which penetrates the deflection | deviation part in a bridge is attained, and favorable fixing performance can be expressed easily and efficiently about this cable.

  Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a schematic structure of an example of a bridge to which this embodiment can be applied. (A) Cable-stayed extradosed bridge, (b) Truss bridge, (c) Box girder bridge, (d) Girder bridge FIG. Although the cable protection method in this embodiment can be applied regardless of the type of bridge, the cable fixing device is applied to a truss bridge whose difference in cable tension is within several percent (eg, 4%) on the left and right of the deflecting portion. Can be assumed. However, the scope of application of the present invention is not limited to such an embodiment. For example, a cable can be used for a cable stayed bridge, an extradosed bridge, a box girder bridge, a girder bridge, and other various bridges. Any bridge can be applied if the adhesion length between the cable and the epoxy resin in the socket inside the fixing device is adjusted to correspond to the cable tension difference between the right and left deflection portions of each bridge.

  Next, a procedure for applying the present invention to such a bridge will be described. FIG. 2 is a diagram showing procedures (a) to (c) in the cable protection method example 1 of the present embodiment. For example, the top of the intermediate support column (tower) of the cable stayed bridge or extradosed bridge, or the upper side of the column head on the intermediate fulcrum of the truss bridge or box girder bridge is used as the deflecting section 1, and a predetermined curvature is first given in the concrete. The provided deflection tube 2 is installed (FIG. 2A). Further, it is assumed that the inner tube 20 penetrates the inner space of the deflection tube 2 (FIG. 2B). The inner pipe 20 is provided with an inlet 21 and an outlet 22 for filling with an epoxy resin. The discharge port 22 has a function of permitting the discharge of the existing material (air, etc.) in the inner tube 20 and the cable accompanying the filling of the epoxy resin, and indicating the completion of filling with the overflow of the epoxy resin from the discharge port 22. Bear.

  The injection port 21 is provided in the inner tube 20 on the inner side of the deflection unit 1 with respect to the position of water stop processing described later in the cable 3. Further, the discharge port 22 is provided in the inner tube 20 at a position opposite to the injection port 21 with the deflection unit 1 in between, and is provided on the inner side of the deflection unit 1 with respect to the water stop treatment position.

  Next, the cable 3 to be protected is inserted into such an inner tube 20 (FIG. 2C). The cable 3 is obtained by removing at least the covering material of the portion 30 corresponding to the abdominal pressure acting section in the deflection tube 2 in the deflection tube 2 in the deflection section 1. The abdominal pressure acting section can be assumed to be, for example, a bowl-shaped range from the curvature point C of the deflection tube 2 to the opening end 23 of the deflection tube 2. In this range, the outward tension from the opening end 23 acting on the cable 3 acts in the abdominal pressure direction in the inner tube 20, and the cable 3 and the inner tube 20 are pressed against each other. . That is, it means a pressure contact section between the cable 3 and the inner pipe 20.

  The cable 3 can be a prefabricated cable as shown in FIG. This prefabricated cable is formed by winding or filling a bundle 4 in which a plurality of galvanized PC steel wires 50 are bundled with a filler 51 (or a molding material) and covering the outside with a high-density polyethylene 52 (HDPE) as a coating material. ) In which the outer periphery of the cross-section is circular and integrated.

  In addition, the cable 3 is a cable in which at least a portion outside the deflecting portion 1 is located at a position outside the deflecting portion 1 relative to the portion 30 corresponding to the abdominal pressure acting section. As an example of the water-stopping treatment, for example, a process in which the water-stopping material is filled in the gap between the stranded wires 50 and the gap between the stranded wire 50 and the covering material 52 that configure the bundled wire 4 inside the covering material 52 is assumed. it can. Thereby, when filling with the epoxy resin with respect to the inner pipe | tube 20 with which the cable 3 was penetrated, it suppresses that an epoxy resin flows out into the cables 3 other than the area which performed the said water stop process.

  FIG. 3 is a diagram showing procedures (d) to (f) in Example 1 of the cable protection method and the fixing method of the present embodiment. If the cable 3 is inserted into the inner tube 20, then, before filling the inner tube 20 of the deflection tube 2 with the epoxy resin, the gap between the end opening 24 of the inner tube 20 and the outer periphery 31 of the cable is determined. Water treatment. This water stop treatment is performed by, for example, fixing the space between the end opening 24 of the inner tube 20 and the cable outer periphery 31 with a heat-shrinkable tube.

  After this fixing is performed, an epoxy resin injection fitting 25 is attached to the inner tube 20 so as to engage with the inlet 21 and the outlet 22 in the cable 3. The injection fitting 25 is provided with, for example, a tube connected to the injection port 21 and the discharge port 22 and can be assumed to protrude from the surface of the injection fitting 25. Therefore, the epoxy resin 7 is filled from the tube (FIG. 3D). By filling the epoxy resin 7, for example, the abdominal pressure acting section in the inner pipe 20 is filled with the epoxy resin 7, and at least a portion of the cable 3 from which the covering material 52 is removed is covered with the epoxy resin 7. Become.

  The cable 3 thus protected by the cable is then subjected to appropriate fixing measures. Therefore, among the cables 3 that pass through the inner tube 20 in the deflection tube 1 in the deflection unit 1 and protrude from the surface of the deflection unit, a predetermined length L from the deflection unit surface (for example, predetermined outward from the cable outer periphery 31). The long covering material 52 is removed. This removal processing may be performed in advance at a factory or the like, or may be performed at the site of cable construction.

  Next, the portion L of the predetermined length is used by using a socket 6 having an inner space that can include the portion L of the predetermined length from which the covering material 52 has been removed and that includes the portion L under a predetermined sealing property. And the epoxy resin 7 is filled in the inner space of the socket 6 (FIG. 3E).

  Further, the cable 3 is connected to the deflecting unit 1 through an adhesive force between the socket 6 and the surface of the deflecting unit and having a predetermined length L from which the covering material 52 is removed and the epoxy resin 7. A taper plate 5 (plate) for transmitting tension is fixed to the socket 6 and the deflecting unit 1 (FIG. 3 (f)). The taper plate 5 (see FIG. 4A) and the deflection unit 1 can be fixed by, for example, bolt fixing. Similarly, the taper plate 5 and the socket 6 can be fixed by, for example, inserting a bolt 70 through a flange portion of the taper plate 5 and fastening with a nut 71 (see FIG. 4B). .

  The structure for fixing the formed cable 3 is as shown in FIG. The socket 6 has a shape in which the inner air surfaces 63 facing each other in a side cross section thereof are substantially parallel and divided in the cable length direction (for example, a structure constituted by two divided pieces 64 each provided with a fastener 65. ) Or a structure capable of opening (for example, a half-cracked structure in which a hinge is arranged in a flexible part), and an inlet 61 and an outlet 62 of the epoxy resin 7. For example, the inlet 61 is provided on the side far from the deflecting unit 1 at the bottom of the socket 6, and the outlet 62 is provided on the side near the deflecting unit 1 at the top of the socket 6.

  It is assumed that the filling of the epoxy resin 7 into the socket 6 is performed from the inlet 61, and the filling is completed after confirming that the epoxy resin 7 is discharged from the outlet 62. In order to increase the temperature of the socket 6 in order to promote the curing of the epoxy resin 7, it is preferable to apply hot air.

  With such a structure, the non-uniform tension of the cable 3 caused by the difference in tension of the cable 3 on the left and right of the deflecting unit 1 is first transmitted to the socket 6 through the adhesion of the epoxy resin 7. This force is transmitted as a bearing pressure to the surface of the deflection unit 1 by the taper plate 5. In addition, this taper plate 5 can adjust the angle between the end surface of the socket 6 and the surface of the deflecting portion 1, and is a steel plate material having a hole into which the cable 3 is loosely inserted in the vicinity of the center portion of the end surface. (See FIG. 4A).

  The cable 3 is inserted through the inner tube 20 of the deflecting unit 1 and is fixed by being tensioned by double pulling using a jack or the like, for example, in an appropriate fixing tool installed on a bridge beam. For the part L having a predetermined length in the inner space of the socket 6, for example, the covering material 52 is peeled off in advance at a cable factory or the cable 3 is tensioned at the site and the position is fixed after the extension is finished. Can be either peeled off.

  Further, the covering material 52 of the cable 3 is made to enter from the both ends of the socket 6 by a slight length. To prevent the epoxy resin 7 filled from the gap between the covering material 52 and the socket 6 from leaking, for example, when the socket 6 divided into two is installed so that one end surface thereof is in contact with the taper plate 5, The hole diameter is made slightly smaller than the outer shape of the covering material 52 of the cable 3 so that the outlet holes at both ends strongly press the covering material 52.

  Further, a flange 66 is attached to the outer side of the socket 6 in the case of being divided in this way along the split surface, and a rubber packing is pasted on the inner surface of the flange 66. That is, if the flanges 66 are brought into contact with each other and fastened by the bolt 65, the rubber packing is brought into pressure contact to ensure water stoppage.

  Further, in order to prevent leakage of the filled epoxy resin 7, before installation of the socket 6, a rubber having an O-ring shape and an inner diameter that is appropriately smaller than the covering material 52 so as to cover the inside of both ends. It is preferable to attach the grout stopper 10 made in advance. In addition, when the silicone water-stopping agent 9 is attached to the diplomatic line between the inner tube 20 and the taper plate 5 and the diplomatic line between the socket 6 and the covering material 52 of the cable 3, the water-stopping property is further increased.

  Further, it is also possible to adopt a configuration in which the deflection tube 2 and the taper plate 5 are originally provided integrally with the socket 6 and the socket 6 is installed, that is, the taper plate 5 is fixed to the deflection unit 1. Thus, means for integrating the deflection tube 2, the taper plate 5, and the socket 6 will be described later.

  Further, a trumpet-shaped enlarged diameter portion 28 is provided at both ends of the deflection tube 2 so that the inner tube 20 and the cable 3 inserted therethrough are brought into contact with and caught by the cable 3 so that the high density polyethylene (HDPE) coating is not damaged. Further, the extension of the diameter-expanding portion is stopped before the surface of the deflecting portion so that the formwork for forming the concrete wall surface of the deflecting portion 1 can be assembled vertically in the easiest manner. Therefore, for example, the outlet 29 on the surface of the deflecting portion is formed by using a divertable rubber hemispherical former.

  Next, another embodiment will be described. FIG. 8 is a diagram showing the procedures (a) and (b) in the cable protection method and the fixing method example 2 of the present embodiment, and FIG. 9 is the procedure in the cable protection method and the fixing method example 2 of the present embodiment ( FIG. 10 is a diagram illustrating steps (e) and (f) in the cable protection method example 2 of the present embodiment. The inner tube 20 is inserted through the deflection tube 2 of the deflection unit 1 (FIG. 8A). Further, the taper plate 5 is inserted into the inner tube 20 and the taper plate 5 is fixed to the surface of the deflecting unit 1 (the fixing method is the same as in the above embodiment). A cap fixing ring 81 (see FIG. 5B) is attached to the end of the inner tube 20 (FIG. 8B).

  The taper plate 5 is provided with an insertion hole 82 that connects the outside of the taper plate 5 and the inside of the inner tube 20. Therefore, when the taper plate 5 is fixed to the surface of the deflecting unit 1, the exhaust hose 80 is passed through the insertion hole 82. The exhaust hose 80 permits the discharge of existing materials (such as air) in the inner tube 20 and the cable accompanying the filling of the epoxy resin 7 as well as the discharge port 22 in the above embodiment, and the epoxy from the discharge hose 80. It can play the role of indicating the completion of filling with the overflow of the resin 7. Further, the outlet of the exhaust hose 80 outward from the taper plate 5 is disposed vertically above the other end outlet of the exhaust hose 80 in the vicinity of the curvature point of the inner pipe 20 so that the exhaust hose 80 such as air is exhausted. It shall prevent the stagnation of the circulation.

  Subsequently, when the cable 3 is inserted into the inner tube 20, the cap 83 is passed through first (FIG. 9C). Similarly to the above-described embodiment, the cable 3 is obtained by removing the covering material 52 of the portion 30 corresponding to the abdominal pressure acting section in the deflection tube 2 out of the paths in the deflection tube 2 in the deflection unit 1. ing. The abdominal pressure acting section can be assumed to be, for example, a bowl-shaped range from the curvature point C of the deflection tube 2 to the opening end 23 of the deflection tube 2. In this range, the outward tension from the opening end 23 acting on the cable 3 acts in the abdominal pressure direction in the inner tube 20, and the cable 3 and the inner tube 20 are pressed against each other. . That is, it means a pressure contact section between the cable 3 and the inner pipe 20.

  Further, as described above with reference to FIG. 6, the cable 3 can be a prefabricated cable. It is assumed that at least the inside of the deflecting unit 1 outside the part 30 corresponding to the abdominal pressure acting section is subjected to a water stop treatment. As an example of the water-stopping process, for example, a process of filling the water-stopping material into the space between the strands 50 that configures the bundle wire 4 inside the covering material 52 can be assumed. Thereby, when filling with the epoxy resin 7 with respect to the inner tube | pipe 20 with which the cable 3 was penetrated, it suppresses that the epoxy resin 7 flows out into the cables 3 other than the area which performed the said water stop process.

  When the cable 3 is inserted into the inner tube 20, a hose nipple 84 for injecting epoxy resin is attached to the inner tube 20. The hose nipple 84 is assumed to have the same function as that of the injection fitting 25 of the epoxy resin 7 described above. Therefore, for example, a tube connected to the injection port 21 and the discharge port 22 is provided, and a tube that protrudes from the surface of the hose nipple 84 can be assumed. Therefore, the epoxy resin 7 is filled from this tube.

  After attaching the hose nipple 84, the spacer 85 (see FIG. 5C) is pushed in and fixed until it abuts against the hose nipple 84, and the cap 83 is fixed to the cap fixing ring 81 (FIG. 9D). )). As a fixing method, a method of inserting bolts and fastening them with bolts can be employed.

  Subsequently, the gap between the cap 83 and the cable 3 is sealed with an appropriate resin material, and the urethane foam 90 is injected between the spacer 85 and the cap 83 (FIG. 10E). The injection process is performed by inserting an injection pipe between the spacer 85 and the cap 83. In the present embodiment, the inner tube 20 is made of steel, and screws are cut outside both ends thereof. Then, the nut 71 is screwed onto the screw cut here and fastened to obtain a cable fixing device.

  Further, an appropriate tube is connected to the hose nipple 84, and the epoxy resin 7 is injected from the tube. By filling the epoxy resin 7, for example, the abdominal pressure acting section in the inner pipe 20 is filled with the epoxy resin 7, and at least a portion of the cable 3 from which the covering material 52 is removed is covered with the epoxy resin 7. Become.

The filling process of the epoxy resin 7 is completed when the existing material (air or the like) in the inner tube 20 or the cable accompanying the filling of the epoxy resin 7 is discharged and the epoxy resin 7 overflows from the exhaust hose 80 (FIG. 10). (F)).
Further, separately from the above-described embodiment, it can be assumed that the deflection tube 2 in the deflection unit 1 is a single tube. FIG. 11 is a diagram illustrating procedures (a) to (d) in Example 3 of the cable protection method and the fixing method in the embodiment. In the present embodiment, in the cable 3 inserted through the single pipe, the epoxy resin 7 is filled into the single pipe corresponding to the portion 130 where the covering material 52 is removed in the abdominal pressure acting section in the deflection pipe 2. Then, at least a portion 130 of the cable 3 from which the covering material 52 has been removed is covered with the epoxy resin 7. Note that the cable 3 from which the covering material 52 is removed not only in the abdominal pressure acting section but also in the entire section of the deflection tube 2 may be inserted into the deflection tube 2 and filled with the epoxy resin 7.

  As an implementation procedure, first, for example, the deflection pipe 2 having a predetermined curvature is installed in the deflection section 1 of the girder bridge (FIG. 11A). In the present embodiment, the curvature is equal to or more than the curvature that generates the abdominal pressure exceeding the wear resistance of the covering material 52 and is equal to or less than the curvature that generates the abdominal pressure not exceeding the wear resistance of the epoxy resin 7. . That is, even if the deflecting tube 2 has a large curvature that should be avoided by using a conventional coating material, if the present embodiment using the epoxy resin 7 is adopted, the deflecting tube having such a large curvature is used. Even 2 can cope.

  Next, the cable 3 is inserted through the deflection tube 2 (FIG. 11B). The deflection tube 2 is provided with an inlet 121 and an outlet 122 for filling with epoxy resin. The discharge port 122 allows the discharge of the existing material (air, etc.) in the deflection tube 2 and the cable accompanying the filling of the epoxy resin, and also indicates the completion of filling with the overflow of the epoxy resin from the discharge port 122. Bear. The injection port 121 is provided on the inner side of the deflecting unit 1 with respect to the position of water stop processing (described later) in the cable 3, and the opening end thereof projects from the surface of the deflecting unit 1. Further, the discharge port 122 is provided in the vicinity of the curvature point C in the deflection tube 2.

  The cable 3 inserted into the deflection tube 1 is obtained by removing the covering material of at least the portion 130 corresponding to the abdominal pressure acting section in the deflection tube 2 in the deflection tube 2 in the deflection unit 1. Yes. The abdominal pressure acting section can be assumed to be, for example, a bowl-shaped range from the curvature point C of the deflection tube 2 to the opening end 23 of the deflection tube 2. In this range, the outward tension from the opening end 23 acting on the cable 3 acts in the abdominal pressure direction in the deflection tube 2, and the cable 3 and the deflection tube 2 are pressed against each other. . That is, it means a pressure contact section between the cable 3 and the deflection tube 2.

  The cable 3 may be a prefabricated cable as already shown in FIG. This prefabricated cable is formed by winding or filling a bundle 4 in which a plurality of galvanized PC steel wires 50 are bundled with a filler 51 (or a molding material) and covering the outside with a high-density polyethylene 52 (HDPE) as a coating material. ) In which the outer periphery of the cross-section is circular and integrated.

  Further, the cable 3 is a cable in which at least a portion outside the deflecting portion 1 is located at least inside the portion 130 corresponding to the abdominal pressure acting section is water-stopped. As an example of the water-stopping treatment, for example, a process in which the water-stopping material is filled in the gap between the stranded wires 50 and the gap between the stranded wire 50 and the covering material 52 that configure the bundled wire 4 inside the covering material 52 is assumed. it can. Thereby, when filling with the epoxy resin 7 with respect to the deflection pipe 2 in which the cable 3 was penetrated, it suppresses that an epoxy resin flows out into the cables 3 other than the area which performed the said water stop process.

  If the cable 3 is inserted through the deflection tube 2, the inner surface 131 of the deflection tube 2 and the covering material 52 of the cable 3 are removed prior to filling the deflection tube 2 with the epoxy resin 7. A water stop process is performed between the outer periphery 133 of the end 132 (FIG. 11C). This water stop treatment is executed by, for example, watertightly fixing the padding material 134 between the inner surface 131 and the cable outer periphery 31. Alternatively, the diameter of the cable 3 is increased beyond the inner diameter of the deflection tube 2 at the part end 132, and the cable 3 is brought into contact with the inner surface of the deflection tube 2 by insertion of the cable 3 into the deflection tube 2. A water stop process may be performed. In any case, various forms of the water stop treatment may be adopted depending on the execution situation or the like.

  Thereafter, the epoxy resin 7 from the injection port 121 is filled, for example, an abdominal pressure acting section in the deflection tube 2 is filled with the epoxy resin 7, and at least the covering material 52 of the cable 3 is removed 130. Is coated with the epoxy resin 7.

  The cable 3 thus protected by the cable is then subjected to appropriate fixing measures (FIG. 11 (d)). FIG. 12 is a cross-sectional view showing a cable fixing structure in Example 3 of the cable protection method and the fixing method of the present embodiment. In this case, of the cable 3 inserted through the deflection tube 1 in the deflection unit 1 and protruding from the surface of the deflection unit, a portion L (for example, a predetermined length outward from the cable outer periphery 31) having a predetermined length from the surface of the deflection unit is covered. The material 52 is removed. This removal processing may be performed in advance at a factory or the like, or may be performed at the site of cable construction.

  Next, the portion L of the predetermined length is used by using a socket 6 having an inner space that can include the portion L of the predetermined length from which the covering material 52 has been removed and that includes the portion L under a predetermined sealing property. And the epoxy resin 7 is filled in the inner space of the socket 6.

  Further, the cable 3 is connected to the deflecting unit 1 through an adhesive force between the socket 6 and the surface of the deflecting unit and having a predetermined length L from which the covering material 52 is removed and the epoxy resin 7. A taper plate 5 (plate) that transmits tension is fixed to the socket 6 and the deflecting unit 1. The taper plate 5 (see FIG. 4A) and the deflection unit 1 can be fixed by, for example, bolt fixing. Similarly, the taper plate 5 and the socket 6 can be fixed by, for example, inserting a bolt 70 through the taper plate 5 and fastening with a nut 71 (see FIG. 4B).

  In the fixing structure of the cable 3 thus formed, the socket 6 has a shape in which the inner air surfaces 63 facing each other in a side cross section thereof are substantially parallel, and is divided in the cable length direction (for example, the fastener 65 is provided). A structure comprising two split pieces 64 provided to each other) or a structure capable of opening (for example, a half-crack structure in which a hinge is arranged in a flexible part), and an inlet 61 and an outlet 62 for epoxy resin 7 It is. For example, the inlet 61 is provided on the side far from the deflecting unit 1 at the bottom of the socket 6, and the outlet 62 is provided on the side near the deflecting unit 1 at the top of the socket 6.

  It is assumed that the filling of the epoxy resin 7 into the socket 6 is performed from the inlet 61, and the filling is completed after confirming that the epoxy resin 7 is discharged from the outlet 62. In order to increase the temperature of the socket 6 in order to promote the curing of the epoxy resin 7, it is preferable to apply hot air.

  With such a structure, the non-uniform tension of the cable 3 caused by the difference in tension of the cable 3 on the left and right of the deflecting unit 1 is first transmitted to the socket 6 through the adhesion of the epoxy resin 7. This force is transmitted as a bearing pressure to the surface of the deflection unit 1 by the taper plate 5. In addition, this taper plate 5 can adjust the angle between the end surface of the socket 6 and the surface of the deflecting portion 1, and is a steel plate material having a hole into which the cable 3 is loosely inserted in the vicinity of the center portion of the end surface. (See FIG. 4A).

  The cable 3 is inserted through the inner tube 20 of the deflecting unit 1 and is fixed by being tensioned by double pulling using a jack or the like, for example, in an appropriate fixing tool installed on a bridge beam. For the part L having a predetermined length in the inner space of the socket 6, for example, the covering material 52 is peeled off in advance at a cable factory or the cable 3 is tensioned at the site and the position is fixed after the extension is finished. Can be either peeled off.

  Further, the covering material 52 of the cable 3 is made to enter from the both ends of the socket 6 by a slight length. To prevent the epoxy resin 7 filled from the gap between the covering material 52 and the socket 6 from leaking, for example, when the socket 6 divided into two is installed so that one end surface thereof is in contact with the taper plate 5, The hole diameter is made slightly smaller than the outer shape of the covering material 52 of the cable 3 so that the outlet holes at both ends strongly press the covering material 52.

  Further, a flange 66 is attached to the outer side of the socket 6 in the case of being divided in this way along the split surface, and a rubber packing is stuck on the inner surface of the flange 66. That is, if the flanges 66 are brought into contact with each other and fastened by the bolt 65, the rubber packing is brought into pressure contact to ensure water stoppage.

  Further, in order to prevent leakage of the filled epoxy resin 7, before installation of the socket 6, a rubber having an O-ring shape and an inner diameter that is appropriately smaller than the covering material 52 so as to cover the inside of both ends. It is preferable to attach the grout stopper 10 made in advance. In addition, when the silicone water-stopping agent 9 is attached to the diplomatic line between the inner tube 20 and the taper plate 5 and the diplomatic line between the socket 6 and the covering material 52 of the cable 3, the water-stopping property is further increased.

  Further, it is also possible to adopt a configuration in which the deflection tube 2 and the taper plate 5 are originally provided integrally with the socket 6 and the socket 6 is installed, that is, the taper plate 5 is fixed to the deflection unit 1. Thus, when the deflection tube 2, the taper plate 5, and the socket 6 are integrated, for example, bolts 100 and nuts 101 are used as shown in FIG. The flange 110 provided on the deflection tube 2, the flange 105 at the socket end, and the taper plate 5 are inserted by the bolt 100 and fastened and fixed by the nut 101. When non-uniform tension is applied to the cable 3 in the right direction, for example, by such fixing measures, the socket 6 is fixed to the deflection tube 2 by the bolt 100 and the nut 101 due to the adhesion of the resin, and is not separated from the deflection unit 1. Thereby, the displacement movement in the abdominal pressure part of the cable 3 is more preferably prevented, and the cable 3 is better protected from frictional damage.

  Further, a trumpet-shaped enlarged diameter portion 28 is provided at both ends of the deflection tube 2 so that the inner tube 20 and the cable 3 inserted therethrough are brought into contact with and caught by the cable 3 so that the high density polyethylene (HDPE) coating is not damaged. Further, the extension of the diameter-expanding portion is stopped before the surface of the deflecting portion so that the formwork for forming the concrete wall surface of the deflecting portion 1 can be assembled vertically in the easiest manner. Therefore, for example, the outlet 29 on the surface of the deflecting portion is formed by using a divertable rubber hemispherical former.

  An embodiment different from the above can be further assumed. Even in the case where there is no difference between the left and right tensions at the deflecting portion in the girder bridge shown in FIG. 1D, the tension itself may fluctuate due to a live load or the like. In this case, there has been a concern about the friction damage of the plated coating of each PC steel wire due to the tension fluctuation and the corrosion accompanying the friction damage. Therefore, in order to eliminate such concerns, cable protection shall be performed as follows. FIG. 14 is a diagram illustrating a cable protection structure at a deflecting unit in Example 4 of the cable protection method and the fixing method of the present embodiment.

  For example, when the insertion length of the cable 3 in the deflection unit 1 is shorter than that in the other embodiments described above, the epoxy resin 7 is filled and cured over the entire cable insertion region in the deflection unit 1. In this process, first, the thin tubes 90 for injecting and discharging the epoxy resin 7 are installed in the gap between both ends of the deflecting unit 1 and the cable 3. Then, a putty-like waterstop material 200 is sealed in the gap and sealed. In this state, the epoxy resin 7 is injected from the thin tube 90. In this way, the adhesion and covering effect between the deflecting portion 1 and each stranded wire by the epoxy resin 7 is manifested, whereby the frictional damage to the plating of the cable 3 and the concern about corrosion due to the frictional damage can be eliminated. In addition, when the epoxy resin 7 is injected, an appropriate water-stop treatment is applied to the inside of the covering material 52 in advance so that the epoxy resin 7 does not enter the cable corresponding to the left and right of the removal section L of the covering material 52 of the cable 3. I shall keep it.

  According to the present invention, it is possible to protect a cable penetrating a deflection portion in a bridge. In addition, by using a high-strength epoxy resin as a filler to fill the socket space, for example, several times the adhesion strength can be obtained compared to conventional grout materials, so the adhesion length with cables such as PC steel materials can be reduced to a few minutes. It is possible to suppress to 1. Accordingly, the total length of the socket can be suppressed, and it is not necessary to process the inner surface of the socket side section into a tapered shape as in the prior art, so that the manufacturing cost and labor of the fixing device can be reduced.

  Even if a galvanized PC steel wire is used as the cable, since epoxy resin is used as the filler, unlike the cement grout, the concern that hydrogen gas is generated can be eliminated.

  Therefore, it is possible to protect the cable penetrating the deflection portion in the bridge, and it is possible to easily and efficiently express good fixing performance for this cable.

  As mentioned above, although embodiment of this invention was described concretely based on the embodiment, it is not limited to this and can be variously changed in the range which does not deviate from the summary.

It is a figure which shows the general | schematic structure of the example of a bridge which can apply this embodiment. It is a figure which shows the procedure (a)-(c) in the cable protection method example 1 of this embodiment. It is a figure which shows the procedure (d)-(f) in Example 1 of the cable protection method and fixing method of this embodiment. It is a figure which shows the (a) taper plate and (b) nut which are used for the cable protection method of this embodiment. It is a figure which shows the (a) cap, (b) cap fixing ring, and (c) spacer which are used for the cable protection method of this embodiment. It is a figure which shows the cross-section of the cable in this embodiment. It is sectional drawing which shows the cable fixing structure in this embodiment. It is a figure which shows the procedure (a) and (b) in Example 2 of the cable protection method and fixing method of this embodiment. It is a figure which shows the procedures (c) and (d) in Example 2 of the cable protection method and fixing method of this embodiment. It is a figure which shows the procedure (e) and (f) in Example 2 of the cable protection method and fixing method of this embodiment. It is a figure which shows the procedure (a) in the example 3 of the cable protection method of this embodiment, and the fixing method, (b). It is sectional drawing which shows the cable fixing structure in Example 3 of the cable protection method and fixing method of this embodiment. It is a figure which shows the example of integral structure of the deflection pipe | tube, the taper plate, and the socket in this embodiment. It is a figure which shows the cable protection structure in the deflection | deviation part in Example 4 of the cable protection method and fixing method of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Deflection part 2 Deflection pipe 3 HDPE coated cable 4 Zinc-plated PC steel wire bundle, bundle wire 5 Tapered plate, plate 6 Socket 7 Epoxy resin 20 Inner tube 30 (Coating material removed) part
50 Galvanized PC steel strand 51 Filler (or molding material)
52 High-density polyethylene (HDPE)

Claims (7)

A cable protection method for inserting a deflection part such as a saddle structure in a bridge,
A step of removing a covering material at a portion corresponding to an abdominal pressure acting section in the deflection pipe of the deflection pipe path out of the cable inserted through the deflection pipe in the deflection section;
Inserting the cable from which the covering material has been removed into the deflection tube;
Filling the deflection tube with an epoxy resin, and coating the portion of the cable from which at least the coating material has been removed with the epoxy resin; and
A cable protection method comprising: In claim 1,
The deflection tube is a single tube, and the epoxy resin is filled into the single tube corresponding to the portion of the cable inserted through the single tube where the covering material is removed in the abdominal pressure acting section in the deflection tube. A cable protection method comprising covering at least a portion of the cable from which the covering material has been removed with an epoxy resin. In claim 1 or 2,
The curvature of the abdominal pressure acting section in the deflection tube is equal to or greater than the curvature that generates the abdominal pressure exceeding the wear resistance of the coating material, and is equal to or less than the curvature that generates the abdominal pressure not exceeding the wear resistance of the epoxy resin. Cable protection method. In claim 1,
The cable protection method, wherein the deflection pipe is a double pipe provided with an inner pipe through which the cable is inserted, and the epoxy resin is filled into the inner pipe. In any one of Claims 1-4,
A cable protection method, wherein the bridge is a truss bridge. It is a structure that protects the cable that passes through the deflection part such as the saddle structure in the bridge,
Inserting the cable from which the covering material in the portion corresponding to the abdominal pressure acting section in the deflection tube in the deflection tube in the deflection unit is removed, into the deflection tube,
A cable protection structure, wherein the deflection tube is filled with an epoxy resin, and at least a portion of the cable from which the covering material has been removed is coated with the epoxy resin. A structure having a structure for protecting a cable inserted into a deflection portion such as a saddle structure in a bridge,
Inserting the cable from which the covering material in the portion corresponding to the abdominal pressure acting section in the deflection tube in the deflection tube in the deflection unit is removed, into the deflection tube,
A structure having a cable protection structure in which an epoxy resin is filled in the deflection tube and at least a portion of the cable from which the covering material has been removed is covered with an epoxy resin.

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