JP2007192011A - Cable anchoring structure of structural body and cable tension adjusting method in cable anchoring structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide, for structures such as a bridge or the like, a cable anchoring structure for a structural body excellent in workability, wherein a work when introducing and anchoring a cable can be smoothly performed. <P>SOLUTION: The cable anchoring structure is composed in such a way that a column body 3 and a fixed girder 2 having opposed webs 6 are connected with a cable 5 and one end of the cable 5 is anchored on an anchor 20 which is fixed between the webs 6. The anchor 20 is provided with a pipe part 21 into which the end portion of the cable 5 is inserted and along the axial direction of the pipe 21, a connection plate 22 whose one end is bonded to a peripheral surface of the pipe 21 while the other end extends toward the web 6, and a tabular flange 23 which is placed on the lower ends of the connection plate 22 and whose portion extending toward the web side is larger than the portion extending in its orthogonal direction. Each tip end edge of the flange 23 and the connection plate 22 is connected to the web 6. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cable fixing structure on a fixing beam side in a cable connecting a columnar body whose axial direction extends in the vertical direction and a fixing beam having webs facing each other, and a cable in the cable fixing structure The present invention relates to a tension adjustment method.

  Conventionally, pillars such as steel towers and main towers of bridges have been installed so that their axial directions extend vertically, and this pillar and the fixing girder are connected with an obliquely extending cable. Stabilization of posture is performed.

  For example, the cable-stayed bridge is constructed by supporting horizontally extending main girders at regular intervals with a main tower. And each main tower and the main girder are mutually connected by the some cable which consists of wire ropes. This cable is inclined and extended between the upper part of the main tower and the main girder, one end in the axial direction is fixed to the upper part of the main tower, and the other end is fixed to the main girder.

  In such a cable-stayed bridge, conventionally, a method of drawing in or how to draw in the end of the cable when the cable is fixed to the main girder is introduced into an anchor provided in the main girder. Various studies have been made.

  For example, Patent Document 1 discloses an invention relating to an introduction device that introduces an axial end of a cable into an anchor of a main girder. This introduction device is arranged on the upper flange of the main girder, and holds the end portion of the cable so as to be introduced into an anchor disposed on the lower side of the introduction device.

  As in Patent Document 1, research has been conducted on the technique of introducing the end of the cable in the axial direction into the anchor, but on the other hand, on the structure itself that fixes the cable to the main girder. The development was almost untouched.

  FIG. 19 is a diagram showing a cable fixing structure that has been generally used conventionally, and shows a working state in which the end of the cable 5 is fixed to the main girder 2 using the anchor 130.

As shown in FIG. 19, the anchor 130 in this example is formed so that the retracting rod 60 corresponds to a four-type cable introducing device 150.
The anchor 130 is formed between the webs 6 constituting the main beam 2, and an insertion portion 131 for inserting the cable 5 is formed at the center thereof. Further, a flange portion 133 that projects outward is provided on the lower end side in the axial direction. The periphery of the insertion portion 131 is surrounded by a plate material 132, and the anchor 130 itself is formed in a large box shape. Furthermore, the flange portion 133 provided on the lower end side protrudes greatly from the insertion portion in the vertical and horizontal directions.
And the attachment part 133a which attaches the edge part of the drawing rod 60 of the cable introduction apparatus 150 is provided in the four corners of the flange part 133. As shown in FIG.

JP-A-2-243808

The anchor 130 in the conventional cable fixing structure is formed so that the retracting rod 60 corresponds to the four-type cable introducing device 150. Therefore, the flange portion 133 is large because it is necessary to provide attachment portions 133a for attaching the end portions of the retracting rod 60 to the four corners of the flange portion 133 of the anchor 130. And since the board | plate material 132 was formed in box shape corresponding to such a flange part 133, the whole shape of the anchor 130 was large.
Moreover, in the anchor in the conventional fixing structure, there exists a situation that the cable insertion part was designed without handling as a stress bearing member. Therefore, the stress bearing member is a box-shaped plate member 132 and a flange portion 133 installed around the cable insertion portion, and the effective cross section of the plate member 132 and the flange portion 133 needs to be enlarged. 130 was upsized.
When the anchor 130 is increased in size, it occupies most of the space formed between the webs 6 of the main beam 2 and there is a problem that workability when the cable 5 is introduced is extremely deteriorated.

  In recent years, a cable introduction device 150 having two pull-in rods 60 has been developed, but no concrete fixing structure corresponding to this has been proposed.

In the present invention, a structure such as a bridge is a cable fixing structure in which the pull-in rod 60 is compatible with the two-type cable introducing device 150, and the work when the cable is introduced and fixed can be smoothly performed. An object of the present invention is to provide a cable fixing structure for a structure having excellent workability.
It is another object of the present invention to provide a cable tension adjustment method that facilitates tension adjustment and improves maintenance efficiency.

  Therefore, the inventor has considered reducing the overall shape of the anchor by considering the cable insertion portion as a stress bearing member that bears stress when designing the anchor. Further, by devising a more specific arrangement of the connecting plates, it is possible to realize a small anchor, and specifically, has the following configuration.

(1) In the cable fixing structure for a structure according to the present invention, a columnar body whose axial direction extends in the vertical direction and a fixing girder having opposing webs are connected by a cable, and one end side of the cable Is fixed to an anchor fixed between the webs, and the anchor includes a pipe portion into which an end portion of the cable is inserted, and an axial direction of the pipe portion. A connecting plate that has one end joined to the outer peripheral surface of the pipe portion and the other end extending toward the web, and a direction that is arranged at least on the lower end side of the connecting plate and extends toward the web A flat plate-like flange portion that is set to be larger than the direction perpendicular thereto, and the leading edges of the flange portion and the connecting plate are joined to the web. It is.

  The column here refers to a main tower that constitutes a cable-stayed bridge, a steel tower that is provided with an antenna, etc., a column that constitutes a general structure, etc. Refers to the body. In addition, the fixed girder is not limited to a long object such as a main girder of a bridge, but also includes a short object formed in a certain length, and a function for fixing one end side of the cable in the axial direction. Means a digit having.

(2) Further, in the above (1), a mounting portion for attaching the drawing rod of the cable introducing device is provided at a position symmetrical to the axis of the pipe portion in the flange portion. Is.

(3) Moreover, in the above-described (1) or (2), the connection plate is formed by connecting a pair of plate members that are opposed to the outer peripheral surface of the pipe portion at a predetermined interval and are joined to each other in the pipe portion. Each of the webs is disposed at a position facing each web, and the spacing between the facing plate members is set such that the spacing at the joint with the web is wider than the spacing at the joint with the pipe portion. It is a feature.

(4) A cable tension adjusting method according to the present invention is a cable tension adjusting method in the cable fixing structure for a structure according to any one of the above (1) to (3). Attaching a mounting member extending in the axial direction of the cable, removably attaching a support member projecting to the web facing the flange portion to the attachment member, and installing a jack cylinder between the support member and the flange portion, The cable tension is adjusted by expansion and contraction of the jack cylinder.

  According to the present invention, first, the anchor can be formed in a flat shape, and the proportion of the anchor in the main girder web can be reduced. Thereby, the work space at the time of an operator performing the operation | work which introduces a cable into the pipe part of an anchor can be ensured in a web. And by ensuring a work space, it becomes possible to work efficiently and safely.

  Further, according to the cable tension adjusting method of the present invention, the cable can be moved in the axial direction with respect to the anchor, and therefore, after the pillar material and the fixing beam are connected by the cable, the structure is completed. Even if it exists, the tension can be easily adjusted by moving the cable in the axial direction, and the efficiency of maintenance can be improved.

[Embodiment 1]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a part of a cable-stayed bridge 1 to which the cable fixing structure of the present invention is applied. The cable stayed bridge 1 includes a plurality of vertically extending main towers 3 arranged at regular intervals, a main girder 2 supported by the main tower 3 via a plurality of cables 5 made of wire rope, and a main girder 2. A floor slab 4 provided on the top is provided. FIG. 1 shows only the vicinity of one main tower 3 among the plurality of main towers 3.

The main girder 2 is arranged so as to pass through an opening provided in the main tower 3, and is supported by each cable 5 from both sides straddling the main tower 3.
One end of the cable 5 is attached to the main tower 3 at regular intervals in the height direction. Further, the other end of the cable 5 is attached to the main beam 2 at regular intervals in the extending direction of the main beam 2. The cable 5 having one end attached to the highest position of the main tower 3 is attached to the main girder 2 at the position farthest from the main tower 3 and the other end is connected to the main tower 3 of the cable 5 in the following order. As the mounting position decreases, the mounting position with the main girder 2 approaches the main tower 3. The cable 5 having one end attached to the lowest position of the main tower 3 is attached to the main girder 2 at the position closest to the main tower 3.

  FIG. 2 shows an outline of the cable fixing structure for the main tower 3 and the cable fixing structure for the main girder 2. In the main tower 3, a plurality of anchors 10 are arranged in the vertical direction at the center in the width direction. FIG. 2 shows one of these anchors 10. The anchor 10 is formed with a hole through which the cable 5 is passed on both front and rear sides in the direction in which the main girder 2 extends, and one end of the cable 5 is passed through this hole and held in a cable socket (not shown). As a result, the anchor 10 is attached.

  The main girder 2 is opposed to each other in the width direction, and a pair of webs 6 extending in parallel to each other and the upper and lower ends of the webs 6 are connected to each other to close the upper and lower portions of the main girder 2. It is comprised from the flange 7 which has. The anchor 20 is fixed to the opposing inner surfaces of the pair of webs 6. The lower end side of the cable 5 is fixed to the anchor 20.

FIG. 3 is an enlarged view of a circled portion A in FIG. FIG. 4 is a plan view of the anchor 20.
As shown in FIG. 3, the cable fixing structure of the present embodiment is formed by joining an anchor 20 to a pair of webs 6 constituting the main girder 2 and fixing the lower end of the cable 5 to the anchor 20. is there.

  The anchor 20 includes a pipe portion 21 into which the cable 5 to be held is inserted, a connection plate 22 projecting from the outer peripheral surface of the pipe portion 21 toward the web 6, and both axial ends of the pipe portion 21 of the connection plate 22. The flange part 23 provided in the position is provided. The anchor 20 is fixed to the main girder 2 in a state where the entire anchor 20 is inclined obliquely so that the axial direction of the pipe portion 21 coincides with the inclination of the cable 5.

  The upper part of the pipe part 21 protrudes above the upper flange of the main girder 2 and is directed to the main tower 3. On the other hand, the lower end of the pipe part 21 is located in the middle of the upper and lower flanges 7 of the main girder 2, and a large gap is formed between the lower end of the pipe part 21 and the lower flange 7.

The connection plate 22 is composed of a pair of plate members that extend in parallel with each other along the axial direction of the pipe portion 21, and the pair of plate materials project toward the webs 6 on both sides of the pipe portion 21.
The connection plate 22 is arranged such that the distance H (see FIG. 3) between the connection plates 22 facing each other is smaller than the diameter dimension D of the pipe portion 21, and the connection plate 22 arranged on the upper side and the lower side. All of the arranged connection plates 22 are arranged in the range of the diameter dimension D of the pipe part 21 in the vertical direction of the diameter direction of the pipe part 21. Specifically, the pair of connection plates 22 are arranged at positions where the pipe portion 21 is divided into approximately three equal parts in the diameter direction.

  The flange portion 23 is a plate material that is disposed orthogonally to the axial direction of the pipe portion 21 at the upper and lower end portions of the connection plate 22, and is formed so as to protrude from the outer peripheral surface of the pipe portion 21 in the vertical and horizontal directions. The flange portion 23 is formed such that the horizontal dimension extending toward the web 6 is larger than the vertical dimension, which is the diameter direction of the pipe portion 21, and the outer shape thereof is flat. The flange portion 23 according to this embodiment is formed in a flat octagon, but is not limited to this, and may be formed in other shapes such as a rectangle as long as both side ends are formed flat. It doesn't matter.

  The pair of connection plates 22 and the pair of flange portions 23 are formed so that the tips in the direction extending toward the web 6 are flush with each other, and the tips of the connection plate 22 and the flange portions 23 are disposed to face each other. Each is joined to the inner surface of the web 6. FIG. 5 shows the shape of the joint portion between the web 6 and the connecting plate 22 and the flange portion 23. In this way, the anchor 20 is fixed to the web 6 of the main beam 2.

  Each flange portion 23 is formed with a through hole 24 penetrating in the plate thickness direction. These through holes 24 are formed at positions symmetrical to the pipe portion 21 in the left-right direction in which the flange portion 23 extends from the pipe portion 21 toward the web 6. These through holes 24 are all formed at the same size from the pipe portion 21, and a line L connecting the through holes located on the same side with respect to the pipe portion 21 is the axial direction of the pipe portion 21. Each is parallel.

  These through holes 24 are holes into which a drawing rod 60 of a cable introduction device (not shown) used when the cable 5 is inserted into the pipe portion 21 of the anchor 20 is inserted. For example, a cable introduction device is installed on the upper surface of the upper flange of the main girder 2, and two drawing rods 60 are extended from the cable introduction device toward the anchor 20. And each drawing rod 60 is inserted in the through-hole 24 formed in the flange part 23 of the anchor 20, respectively, and these front-end | tips protrude from the flange part 23 located in a lower end side. A fixing tool 61 is attached to the tip of the protruding retracting rod 60, and the retracting rod 60 is fixed to the flange portion 23. In this state, the cable introduction device is driven, a reaction force is applied to the anchor 20 by the drawing rod 60, and the cable 5 is pushed into the pipe portion 21 of the anchor 20.

  A cylindrical cable socket 31 is provided at the lower end portion of the cable 5 pushed into the pipe portion 21, and a donut-shaped support plate 30 and shim plate are provided between the cable socket 31 and the lower end portion of the pipe portion 21. 34 is arranged to hold the cable socket 31 so as not to come out of the pipe portion 21.

  In addition, a mechanism capable of holding the end of the cable 5 and moving the cable 5 with respect to the axial direction can be attached to the lower end side of the anchor 20 during maintenance. 6 is a perspective view of such a mechanism attached to the anchor 20, FIG. 7 is a plan view, and FIG. 8 is a side view. Below, the procedure at the time of giving tension | tensile_strength at the time of a maintenance, for example, when the cable 5 becomes loose is demonstrated.

  First, an attachment screw 32 for attaching a support plate 33 (described later) to the lower end portion of the cable socket 31 is installed. In the installation of the mounting screw 32, a screw hole is provided at the lower end of the cable socket 31, and the end of the mounting screw 32 is screwed into this screw hole.

  Like the flange portion 23, the support plate 33 is formed in a flat octagonal shape whose vertical dimension is significantly smaller than that in the horizontal direction. A through hole penetrating in the thickness direction is formed at the center, and the mounting screw 32 is inserted into the through hole. Then, a shim plate 34 is installed from the outside of the support plate 33 and fixed with a nut 35.

  The jack cylinders 50 are arranged on both sides of the pipe portion 21 between the flange portion 23 on the lower end side and the support plate 33. The jack cylinder 50 employs a hydraulic cylinder and includes a cylindrical cylinder tube 51 and a cylinder rod 52 having one end inserted into the cylinder tube 51. In the jack cylinder 50, the rear end of the cylinder tube 51 is abutted against the flange portion 23, the distal end side of the cylinder rod 52 is directed toward the support plate 33, and the distal end is abutted against the support plate 33. The cylinder rod 52 is configured to be able to reciprocate in the axial direction inside the cylinder tube 51, and the full length of the jack cylinder 50 expands and contracts as the cylinder rod 52 reciprocates.

  A threaded portion 53 is provided at the tip of the cylinder rod 52 so as to protrude in the axial direction. The threaded portion 53 of the cylinder rod 52 passes through the through hole of the support plate 33, and the nut 54 is screwed from the outside of the support plate 33. As a result, the support plate 33 is fixed to the cylinder rod 52 of the jack cylinder 50.

When the jack cylinder 50 is installed as described above, the support rod 33 is moved downward by extending the cylinder rod 52 of the jack cylinder 50, thereby moving the cable socket 31 downward via the mounting screw 32. Then, tension is applied to the cable 5 or the degree of drawing of the cable 5 into the anchor 20 is adjusted.
After such adjustment, a shim plate 34 is added between the lower end of the pipe portion 21 and the cable socket 31 so that the tension of the cable 5 is maintained. After the above adjustment, the jack cylinder 50 and the support plate 33 are not necessary, and therefore, the jack cylinder 50 and the support plate 33 are removed from the anchor 20 as shown in FIG.

According to the cable fixing structure having the above configuration, first, fixing work of the cable 5 can be greatly improved.
That is, the anchor 20 employed in this cable fixing structure has a pair of connecting plates 22 accommodated within the range of the diameter dimension D of the pipe portion 21 and the flange portion 23 is formed in a flat shape. Since the anchor 20 is attached, a large working space can be left in the web 6 of the main girder 2.

This is compared with the conventional anchor 130 with reference to FIG. In FIG. 9, the anchor shown on the left side is the same as the anchor 130 of the prior art shown in FIG. 19, and the anchor shown on the right side of FIG. 9 shows the anchor 20 according to this embodiment.
The anchor 130 shown in FIG. 19 is an example in which the insertion portion 131 does not extend beyond the lower flange portion 133. However, the anchor 130 shown in FIG. 9 is not used for comparison with the present embodiment. Similar to the embodiment, the insertion portion 131 extends below the lower flange portion 133.

  In the conventional anchor 130, the flange portion 133 protrudes from the center insertion portion 131 into which the cable 5 is inserted to the left and right and up and down. In addition, a plate member 132 for connecting and fixing the anchor 130 to the web 6 is also provided at a position vertically deviated from the insertion portion 131 into which the cable 5 is inserted. For this reason, the outer shape of the anchor 130 itself becomes large, and at the position where the anchor 130 is fixed, the space in the web 6 is almost occupied by the anchor 130. In particular, as shown in FIG. 9, when the rib 8 protrudes from the upper and lower flanges 7 at the position where the anchor 130 is installed, there is almost no gap between the rib 8 and the anchor 130. .

  In such a conventional anchor 130, when the operator moves to a position before and after the anchor 130 with respect to the direction in which the main girder 2 extends, the worker once goes out of the space in the main girder 2 and goes out of the main girder 2. 2 must move outside. In order to move outside the main girder 2, it is necessary to move to the upper side of the upper flange 7 or to separately provide a scaffold on the left and right of the main girder 2. In this case, improvement in work efficiency cannot be expected.

  In this regard, in the anchor 20 according to the present embodiment shown on the right side of FIG. 9, a wide working space is formed above and below the anchor 20. For this reason, the space formed by the web 6 and the upper and lower flanges 7 of the main girder 2 can be moved as it is even when moving to both sides of the anchor 20 in the extending direction of the main girder 2. Thereby, working efficiency can be improved significantly.

  Also, the tension of the cable 5 can be freely set by attaching a support plate 33 to the cable socket 31 and moving the jack cylinder 50 in the axial direction of the pipe portion 21, that is, the axial direction of the cable 5 passed through the pipe portion 21. . In addition, when the cable 5 once fixed is later maintained, if the cable socket 31 is pulled away from the anchor 20 using the jack cylinder 50, the maintenance can be easily performed. Since the support plate 33 and the jack cylinder 50 are detachable from the anchor 20, they can be detached from the cable fixing structure after the fixing work of the cable 5 is finished.

  As described above, the cable fixing structure using the anchor 20 in which the connection plates 22 are configured in parallel with each other has been described as an example, but the present invention is not limited to this. FIG. 10 shows an example in which an anchor 70 is used in which opposing connection plates 72 are arranged so as to expand outwardly.

  The connecting plate 72 of the anchor 70 shown in FIG. 10 extends from the outer peripheral surface of the pipe portion 71 toward the web 6 of the main beam 2. The connecting plates 72 facing each other are arranged so that the distance between the connecting plates 72 is increased from the pipe portion 71 toward the web 6. And the flange part 73 located in the both ends in the axial direction of the pipe part 71 is formed in the rectangle. Further, the anchor 70 is provided with a connecting plate 75 that connects the connecting plates 72 facing each other. The connecting plate 75 connects the opposing surfaces of the connecting plate 72 to each other slightly inside the outer edge of the connecting plate 72. In this anchor 70 as well, a through hole 74 is formed in the flange portion 73 at a position that is symmetrical with respect to the pipe portion 71. The through-hole 74 is a hole for inserting a drawing rod of the cable introduction device.

  Like the anchor 70 shown in FIG. 10, the stress flow can be made smooth at the joint portion between the connection plate 72 and the web 6 by widening the interval between the connection plates 72 facing each other toward the web 6. it can. On the other hand, even if the interval between the connection plates 72 is increased toward the web 6, the interval between the connection plates 72 is still within the diameter range of the pipe portion 71 in the vicinity of the pipe portion 71. A large work space is secured in the web 6 of the main girder.

[Embodiment 2]
Next, a second embodiment of the present invention will be described with reference to FIGS.

  The cable fixing structure according to the second embodiment is different from the cable fixing structure according to the first embodiment in the structure of the anchor 80 used. The anchor 80 is also arranged between the webs 6 constituting the main beam 2, and the pipe part 81 into which the cable 5 is inserted and the outer peripheral surface of the pipe part 81 toward the two opposing webs 6. Each of the connecting plates 82 projects from each other and a pair of flange portions 83 projecting outward from the outer peripheral surface of the pipe portion 81 at both end portions of the connecting plate 82.

As with the pipe portion 21 of the anchor 20 according to the first embodiment, the pipe portion 81 of the anchor 80 protrudes from the space in the web 6 of the main girder 2 from the upper flange 7 of the main girder 2 and has an upper end. Is directed to the main tower 3. On the other hand, the lower end of the pipe part 81 is positioned in the middle of the upper and lower flanges 7 of the main girder 2, and a large gap is formed between the lower end of the pipe part 81 and the upper and lower flanges 7.
In the cable fixing mechanism according to the second embodiment, the lower end of the pipe portion 81 is in contact with the inner surface of the lower flange portion 83, and the bearing plate 30 and the shim plate 34 are formed on the outer surface of the flange portion 83. is set up.

  The connection plate 82 is provided only at the center in the vertical direction that forms the diameter direction of the pipe portion 81. The connection plate 82 is made of a plate material arranged along the axial direction of the pipe portion 81 at the center portion of the pipe portion 81, and is provided so as to protrude from the outer peripheral surface of the pipe portion 81 toward the web 6 to the left and right. .

  The basic configuration of the flange portion 83 is the same as that of the anchor 20 according to the first embodiment. That is, the flange portion 83 is a plate material arranged orthogonal to the axial direction of the pipe portion 81, and is formed so as to protrude from the outer peripheral surface of the pipe portion 81 in the vertical and horizontal directions. And the dimension of the left-right direction extended toward the web 6 is formed so that it may become large with respect to the dimension of the up-down direction which is the diameter direction of the pipe part 81 material, and the external shape is made into the flat octagon. The shape of the flange portion 83 is not limited to a flat octagon, and may be formed in other shapes such as a rectangle as long as both side ends are formed flat.

  The connection plate 82 and the pair of flange portions 83 are formed so that the tips in the direction extending toward the web 6 are flush with each other, and the web 6 faces the tips of the connection plate 82 and the flange portion 83. Connected to the inner surface. FIG. 12 shows the shape of the connection surface between the web 6 and the connection plate 82 and the flange portion 83. In this way, the anchor 80 is fixed to the web 6 of the main beam 2.

  And in this anchor 80, the insertion pipe | tube 84 is provided in the both sides of the pipe part 81 so that the flange parts 83 may be connected. Each flange portion 83 is formed with a through hole 85 penetrating the plate thickness direction with the pipe portion 81 interposed therebetween. These through holes 85 are formed at positions symmetrical to the pipe portion 81 in the left-right direction in which the flange portion 83 extends from the pipe portion 81 toward the web 6. These through holes 85 are respectively formed at positions having the same dimensions as the pipe portion 81, and a line L (see FIG. 14) connecting the through holes 85 located on the same side with respect to the pipe portion 81 is the pipe portion 81. Are parallel to each other.

  On the other hand, the connection plate 82 is provided with an insertion tube 84 that connects the above-described through holes 85 formed on the same side with respect to the pipe portion 81 of each flange portion 83. The insertion pipes 84 are respectively arranged in parallel with the axis of the pipe portion 81 located at the center of the anchor 80.

  The through-hole 85 and the insertion tube 84 are inserted with a drawing rod of a cable introduction device used when the cable 5 is inserted into the pipe portion 81 of the anchor 80.

In the fixing structure of the cable 5 according to the second embodiment, the flange 83 on the lower end side holds the end of the cable 5 and holds the cable 5 as shown in FIGS. A mechanism capable of moving with respect to the axial direction can be provided. Since this mechanism has the same configuration as that of the cable fixing mechanism according to the first embodiment, the same members will be denoted by the same reference numerals and only the outline will be described. A support plate 33 is detachably attached to an attachment screw 32 attached to the cable socket 31 below the lower flange portion 83. Between the flange portion 83 and the support plate 33, jack cylinders 50 are respectively disposed on the left and right sides of the cable socket 31 as a center.
The above mechanism is used for adjusting the tension of the cable 5 or used for maintenance.

[Embodiment 3]
In the cable fixing structure in the first embodiment and the second embodiment described above, the case where the pulling rod of the cable introduction device is fixed to the flange portion on the lower end side in the axial direction of the pipe portion among the one flange portion. Although it is assumed, the retracting rod may be fixed to the flange portion on the upper end side.

  FIG. 15 shows a cable fixing structure according to the third embodiment, and shows a cable fixing structure in which the pull-in rod 60 is fixed to the flange portion 93 on the upper end side. The anchor 90 of the cable fixing structure includes a pipe portion 91 into which the cable 5 is inserted, a connection plate 92 projecting from the outer peripheral surface of the pipe portion 91 toward two opposing webs, and a shaft of the pipe portion 91. It is composed of a pair of flange portions 93 projecting outward from the outer peripheral surface of the pipe portion 91 at the positions of both end portions of the connection plate 92 in the direction.

  The anchor 90 of the cable fixing structure according to the third embodiment is similar to the anchor 80 of the cable fixing structure according to the second embodiment described above in the basic structure of the pipe portion 91, the connection plate 92, and the flange portion 93. is there. However, a unique structure is provided to fix the retracting rod 60 to the flange portion 93 on the upper end side.

  First, in the flange portion 93, a through-hole penetrating the plate is formed only in the flange portion 93 on the upper end side. However, these through holes are also formed on both sides of the pipe portion 91 so as to be symmetrical about the pipe portion 91 in the direction in which the flange portion 93 extends from the pipe portion toward the web. On the other hand, the connection plate 92 is formed with two rectangular cutouts 94 at the upper edge. These notches 94 are respectively formed at positions corresponding to the through holes formed in the flange portion 93. A holder 65 made of a threaded steel pipe is attached to the notch 94 by welding.

  The retracting rod 60 is inserted into the through hole of the flange portion 93 from the upper side of the anchor 90, and the lower end thereof is screwed into the holder 65 and held. As a result, the lower end of the retracting rod 60 is fixed to the anchor 90 so that the reaction force generated when the cable 5 is retracted can be supported by the anchor 90.

  In addition, the form of the flange part which comprises an anchor can employ | adopt the thing of various forms besides the thing concerning the 1st-3rd embodiment. Some examples are illustrated and described.

  In the anchor 100 shown in FIG. 16, the upper end side of the connecting plate 102 is formed flat in a direction orthogonal to the axial direction of the pipe material 101, while the lower end side is directed toward the center as it goes downward. It is formed in a tapered shape. The flange portions 103 and 104 are provided with forms corresponding to the upper and lower ends of the connection plate 102. That is, the flange portion 103 on the upper end side is provided so as to protrude from the outer peripheral surface of the pipe portion 101 to the left and right perpendicular to the axial direction of the pipe portion 101. On the other hand, the flange portion 104 on the lower end side projects from the outer peripheral surface of the pipe portion 101 toward the left and right and is inclined obliquely toward the upper end side.

  The anchor 100 shown in FIG. 16 is of a type in which the retracting rod is fixed to the flange portion on the upper end side.

  In contrast to the anchor 100 shown in FIG. 16, the anchor 110 shown in FIG. 17 is formed so that the lower end side of the connecting plate 112 is flat in the direction orthogonal to the axial direction of the pipe portion 111, while the upper end side Is tapered toward the center as it goes upward. The flange portions 113 and 114 are provided so as to correspond to the upper and lower ends of the connection plate 112. That is, the flange portion 113 on the upper end side projects from the outer peripheral surface of the pipe portion 111 toward the left and right, and is inclined and inclined toward the lower end side. On the other hand, the flange portion 114 on the lower end side is provided so as to protrude from the outer peripheral surface of the pipe portion 111 to the left and right perpendicular to the axial direction of the pipe portion 111. The anchor 110 shown in FIG. 17 is of a type in which the retracting rod is fixed to the flange portion 114 on the lower end side.

  FIG. 18 shows an anchor 120 according to yet another embodiment. The anchor 120 has an outer shape formed in a rectangular shape on the connecting plate 122, and is provided so as to protrude from the vertical center position in the diametrical direction of the pipe portion 121 to the left and right. And the flange part 123 is provided only in the lower end side of this connection board. The flange portion 123 extends from the outer peripheral surface of the pipe portion 121 to the left and right so that it is orthogonal to the axial direction of the pipe portion 121.

  Note that the anchors shown in FIGS. 16 to 18 are also formed so that the leading edge of the connection plate and the leading edge of the flange portion are flush with each other.

  The anchor of the cable anchoring structure described above may be appropriately selected according to the form of the cable-stayed bridge to be applied and the allowable value of the stress generated between the anchor and the main girder web.

  In the above description, the case where the cable is arranged at the center in the width direction of the bridge has been described as an example, but the bridge is a so-called two-side suspension type in which the cable is arranged on both sides of the bridge. You may apply to. Moreover, the structure to apply is not limited to a bridge. For example, when a tower such as an antenna is supported by a cable with its axial direction extending vertically, one end of the cable is fixed to, for example, a fixing girder provided in a building, and the other end is fixed to this Connect to the tower. Thus, the cable fixing structure of the structure can also be applied to a general structure.

It is a perspective view of a cable-stayed bridge to which the cable fixing structure of the present invention is applied. It is explanatory drawing which shows the cable fixing structure provided in the main tower and main girder of the cable-stayed bridge shown in FIG. 1 is a perspective view of a cable fixing structure according to a first embodiment of the present invention. FIG. 4 is a plan view of the cable fixing structure shown in FIG. 3. It is a figure which shows the shape of the junction part of the anchor and the main girder web which comprise the cable fixing structure shown in FIG. It is a perspective view explaining the state at the time of the maintenance in the cable fixing structure concerning the 1st Embodiment of this invention. It is a top view explaining the state at the time of the maintenance in the cable fixing structure shown in FIG. It is a side view explaining the state at the time of the maintenance in the cable fixing structure shown in FIG. It is a figure which shows the comparison with the anchor of the conventional cable fixing structure, and the cable fixing structure concerning 1st Embodiment. It is a cross-sectional view of an anchor showing a modification of the anchor according to the first embodiment. It is a perspective view of the anchor used for the cable fixing structure which concerns on 2nd Embodiment. It is a figure which shows the shape of the junction part of the anchor and the web of a main girder which comprise the cable fixing structure shown in FIG. It is a perspective view explaining the state at the time of the maintenance in the cable fixing structure shown in FIG. It is a top view explaining the state at the time of the maintenance in the cable fixing structure shown in FIG. The perspective view of the anchor used for the cable fixing structure concerning the 3rd Embodiment of this invention. It is a perspective view which shows the modification of the anchor which comprises a cable fixing structure. It is a perspective view which shows the modification of the anchor which comprises a cable fixing structure. It is a perspective view which shows the modification of the anchor which comprises a cable fixing structure. It is a perspective view which shows the conventional cable fixing structure.

Explanation of symbols

1 Cable stayed bridge 2 Main girder 3 Main tower 5 Cable 20, 70, 80, 90 Anchor 21, 71, 81, 91 Pipe part 22, 72, 82, 92 Connection plate 23, 73, 83, 93 Flange part 24, 74 , 85 Through hole 30 Pressure bearing plate 31 Cable socket 32 Mounting screw 33 Support plate 34 Shim plate 50 Jack cylinder 60 Pull-in rod 84 Insertion tube 94 Notch 100, 110, 120 Anchor 101, 111, 121 Pipe portion 102, 112, 122 Connection Plate 103, 113, 123 Flange 114, 124 Flange

Claims (4)

A structure in which a columnar body whose axial direction extends in the vertical direction is connected to a fixing beam having an opposing web with a cable, and one end of the cable is fixed to an anchor fixed between the webs. Cable fixing structure of the object,
The anchor is disposed along the axial direction of the pipe portion into which the end portion of the cable is inserted, and one end side is joined to the outer peripheral surface of the pipe portion, and the other end faces the web. And a flat plate-like flange portion that is arranged at least on the lower end side of the connection plate and has a direction extending toward the web side that is set larger than a direction perpendicular to the connection plate. ,
A cable fixing structure for a structure according to claim 1, wherein each edge of the flange portion and the connection plate is joined to the web. 2. The cable fixing structure for a structure according to claim 1, wherein a mounting portion for attaching the drawing rod of the cable introduction device is provided at a position symmetrical to the axis of the pipe portion in the flange portion. The connection plate is formed by arranging a pair of plate members that are opposed to and joined to the outer peripheral surface of the pipe portion at a predetermined interval, at portions facing the respective webs in the pipe portion. 3. The cable fixing structure for a structure according to claim 1, wherein the distance at the joint portion with the web is set larger than the distance at the joint portion with the pipe portion. A cable tension adjusting method in a cable fixing structure for a structure according to any one of claims 1 to 3,
An attachment member extending in the axial direction of the cable is attached to the end portion of the cable, and a support member that protrudes toward the web facing the flange portion is detachably attached to the attachment member, and a jack is interposed between the support member and the flange portion. A cable tension adjusting method comprising: installing a cylinder and adjusting the tension of the cable by expansion and contraction of the jack cylinder.

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