JPH0874210A - Corrosion preventive treatment on anchoring part of installation cable - Google Patents

Abstract

PURPOSE: To improve the workability by providing a protective pipe on the side of an anchoring part of a cable, providing a spacer furnished with a through hole to maintain arrangement of the cable on the side of a free end of the protective pipe and making it contact with the cable to be inserted with pressure by way of providing an elastic material in the through hole of the spacer. CONSTITUTION: A plural number of spacers 9 and elastic bodies 10 arranged in a sandwich shape between the spacers are provided through an adapter 8a on the side of a free end of a protective pipe 8, single cables 11 fixed on an anchoring member 4 through these spacers 9 and the elastic bodies 10, and the cables 11 are installed in a tensional state. Through holes in the number corresponding to the number of the single cables 11 respectively are arranged in specified arrangement with equal intervals. Additionally, an inner diameter of the through holes provided on each of the spacers 9 is formed larger by roughly ten percent than an outer diameter of the cables 11 to be inserted and the through holes provided on the elastic bodies 10 are formed smaller by roughly ten percent than the outer diameter of the cables 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rust-proofing a fixing portion of an erection cable stretched with a predetermined tension in a cable-stayed bridge or suspension bridge.

[0002]

2. Description of the Related Art As an anticorrosion treatment or an anticorrosion treatment for a fixing portion in this type of erection cable, for example, Japanese Patent Publication No. 2-374.
Those disclosed in Japanese Patent Laid-Open No. 63-63 and Japanese Patent Publication No. 3-30644 are known as conventional examples.

In the above-mentioned conventional example, a tube having a bottom plate provided with a predetermined through hole is provided inside the cable fixing portion by connecting to the fixing plate, and after inserting the cable into the through hole, the tube is fixed. In addition to injecting a filler into the inside, an elastic material is inserted between a bottom plate and a steel plate or a plastic plate, and the both are tightened to deform the elastic material so that the elastic material is brought into close contact with the covering portion of the cable.

Further, in the above-mentioned conventional example, a durable elastic material having a predetermined through hole is arranged between the inside of the cable fixing device and the steel plate or the hard plastic plate, and the fixing device and the steel plate or the hard plastic plate are used for fixing. From the outside of the tool, tighten the bolt to deform the elastic material and bring it into close contact with the sheath of unbonded PC steel strand, or make the elastic material an expansive material and expand it in a humid environment to unbond it. By closely contacting with the sheath sheath of the PC steel stranded wire, the water can be stopped even after the tension of the cable is fixed.

[0005]

The above-mentioned conventional anticorrosion treatment has a structure in which a pipe having a bottom plate is attached to a fixing plate, and the pipe is inside a through hole provided in a fixing portion such as a cable-stayed bridge. However, it is difficult to tighten the bolts from the outside of the bottom of the pipe after the cable is stretched, resulting in poor workability.

Further, in the above-mentioned conventional anticorrosion treatment, an elastic material is directly provided inside the cable fixing tool, and a bolt is tightened from the outside of the fixing tool to deform the cable fixing tool. When the fixing tool and the elastic body are adjacent to each other,
In order to fix the long unbonded PC steel wire to the fixing tool, it is strictly required to have the length dimension accuracy to peel off the coating sheath to make a bare wire, and the work efficiency of fixing the wire in consideration of tension and slackness. In addition to the decrease in the work efficiency, a cap for waterproofing must be provided on the outer side of the fixing tool, which also causes a problem that work efficiency is reduced.

Further, in both of the above-mentioned conventional examples, the elastic body is deformed by tightening so that the elastic body and the covering sheath of the unbonded PC steel wire are brought into close contact with each other. The insertion hole of the unbonded PC steel wire provided in the hard plastic plate cannot be so large, and the work of inserting the unbonded PC steel wire into the elastic body and the steel plate or the hard plastic plate is troublesome. It also has the problem of poor sex.

[0008]

As a concrete means for solving the above-mentioned problems of the conventional example, the present invention provides a protective tube for protecting the fixing portion side of the cable in the fixing portion of the erection cable supporting the cable-stayed bridge or the like. A spacer having a through hole for maintaining the arrangement of the cables is provided on the free end side of the protective tube, and an elastic material is provided in the through hole of the spacer so as to press-contact the inserted cable. And a method for preventing rust in the fixing portion of the erection cable, wherein a plurality of the spacers are arranged adjacent to each other, and an elastic material is arranged between the spacers. The elastic material is plate-shaped, and a through-hole having a diameter smaller than the outer diameter of the cable is provided at a position corresponding to the through-hole of the spacer; the elastic material is O-ring-shaped and outside the spacer. Diameter smaller than diameter; and spacer It is also intended to include the technical idea of the present invention filled with waterproofing agent to at least a portion of the through hole.

[0009]

[Function] On the fixing portion side of the cable, a protective tube provided with a spacer and an elastic material for maintaining the arrangement of the cable is provided, and the end portion of the fixed portion of the cable is simply inserted into the corresponding through hole of the spacer. The cable is pressed and supported in a waterproof state by the elastic material, improving not only the workability of the cable erection, but also the inside of the protective tube is shut off from the outside, and the structure prevents moisture from entering the cable from entering. , Nearly complete rust prevention can be achieved at the fixing part of the cable.

[0010]

EXAMPLES Next, the present invention will be described in more detail with reference to the illustrated examples. In the first example shown in FIGS. 1 to 4, 1 is a main girder such as a cable-stayed bridge. A plurality of cables are stretched or erected between columns (not shown) to support the bridge girder, and the plurality of cables are, for example, PC steel stranded wire or unbonded PC coated with polyethylene resin. A stranded wire or the like is used, and a predetermined number, for example, 19 of these cables are combined to form a single cable, and a large number of these cables are installed.

In the embodiment of the present invention, the fixing portion of one cable among a large number of cables is described. An outer cylinder tube 3 is arranged in a through hole 2 for fixing a cable provided in the main girder 1, and a fixing member 4 is attached to one end of the outer cylinder tube 3.

The fixing member 4 includes, for example, a fixing plate 5 and
It is composed of a supporting member 6 and a fixing block 7, and the outer tube 3 is attached such that one end thereof is substantially fixed to the fixing plate 5.

A protective tube 8 is provided inside the outer tubular tube 3,
The protective tube 8 is attached with one end thereof fixed to the support member 6 or the fixing block 7, and has a substantially double tube structure together with the outer tube 3.

On the free end side of the protective tube 8, an adapter 8a
A plurality of (three in the illustrated embodiment) spacers 9 and elastic bodies 10 arranged in a sandwich shape between the spacers are provided through the spacers 9 and the spacers 9.
The single cable 11 is fixed to the fixing member 4 by penetrating through and and is installed in a tension state.

As a fixing method at each end of the cable 11 with respect to the fixing member 4, a fixing means using a wedge material which has been conventionally used can be directly adopted. That is, the bare ends of the cable 11 from which the sheath has been peeled off are inserted into a large number of tapered through holes provided in the fixing block 7, and the wedge member 12 is bitten and fixed.

In the cable 11 fixed in this way, a so-called important component for rustproofing or waterproofing the fixing portion is a spacer 9 attached to the protection tube 8 via an adapter 8a. And the elastic body 10, and these components will be described in detail.

The plurality of spacers 9 attached to the adapter 8a are, for example, disks made of metal or synthetic resin, and the elastic body 10 is, for example, rubber or sponge. The body 10 and the body 10 are sandwiched, and the bolts 13 are fastened at a plurality of points with appropriate bolts 13 so that water is not leaked between them. The adapter 8a is attached to the free end of the protective tube by welding, bonding means, or the like in a substantially integrated manner.

The spacers 9 and the elastic body 10 are provided with through holes 14 and 15 in a predetermined arrangement at equal intervals corresponding to the number of the single cables 11. These through holes 14 and 15 are used for the fixing block 7.
The arrangement of the fixing through holes and the arrangement of the fixing through holes substantially correspond to each other, and in particular, the spacer 9 serves to maintain the arrangement state of the cables 11.

Further, the through hole 1 provided in each spacer 9
The inner diameter of 4 is formed to be approximately 10% larger than the outer diameter of the single cable 11 to be inserted, and conversely, the through hole 15 provided in the elastic body 10 is approximately 10% smaller than the outer diameter of the cable 11. It is formed.

For example, if the outer diameter of the cable 11 used is 18 mm, the inner diameter of the through hole 14 formed in the spacer 9 is approximately 20 mm, and the through hole provided in the elastic body 10 is formed. The inner diameter of 15 is formed to be approximately 15 to 16 mm.

The cable 11 used is, for example, PC steel stranded wire or unbonded PC steel stranded wire, and as shown in FIG. 3, at the end portion on the fixing side, the portion of the sheath portion 11a which has been precoated is attached. It is peeled off over a predetermined length to expose the bare wire portion 11b of a predetermined length.

Then, at the end of the cable 11 on the side where it is inserted into the outer tube 3 and the protective tube 8, the surface of the sheath 11a is covered with a water-blocking agent 16 that also serves as a lubricant such as grease over a predetermined length. Is applied and inserted into a predetermined through hole 14.

At this time, the waterproofing agent 16 is applied to the bare wire portion 1
It is applied so as not to reach 1b, and is inserted so as to project from the bare wire portion 11b into the through hole 14. Generally, a guide wire having a predetermined length is provided in advance from the through hole of the fixing block 7 to the through hole 1 of the spacer 9 and the elastic body 10.
4 and 15, the bare wire portion 11b at the tip of the cable 11 is locked or connected to one end of the guide wire, and the other end of the guide wire is pulled from the outside of the fixing block 7, thereby 11 is sequentially inserted through the through holes 14 and 15 of the spacer 9 and the elastic body 10 to the through hole of the fixing block 7.

At the time of this insertion, the through hole 14 is provided with the cable 1
Since it is formed larger than the outer diameter of No. 1, it is inserted in this portion without receiving any resistance. However, since the through-hole 15 is formed smaller than the outer diameter of the cable 11, first, the bare wire portion 11b passes through by penetrating the through-hole 15 and then the portion covering the sheath portion 11a passes through. Further, the through hole 15 is pushed and expanded to pass through and inserted.

In this way, the cable 11 is inserted by expanding the small through hole 15 of the elastic material 10 and inserting it.
The waterproofing agent 16 applied to the peripheral surface is the elastic material 10 of the first step.
It is squeezed by and is accumulated in the through hole 14 of the spacer 9 located on the insertion side. Still, a part of the waterproofing agent 16 passes through the elastic material 10 in the first step, but by being further squeezed by the elastic material 10 in the second step, there is a gap between the elastic materials in the first step and the second step, especially in the second step. It will accumulate in the vicinity of the through hole of the elastic member 10 of the eye.

The elastic member 10 itself tightens the cable 11 through the through hole 15, and at the same time, due to the strong tightening, the elastic member 10 is deformed so as to be pulled and inclined in the insertion direction of the cable, and the state is maintained.
Each end portion of 1 is fixed to the fixing block 7, and when the wedge member 12 is used at the time of fixing, it acts so as to return in a direction opposite to the insertion direction, and by the returning action, the elastic member for the cable 11 is returned. The abutting action of 10 is further increased, so that the cable is tightly pressed and the cable is laid while maintaining a predetermined degree of tension with the pressed contact.

When the cable 11 is inserted from the side opposite to the above, the form of the elastic body 10 with respect to the cable 11 is the same as that described above by temporarily extending the cable once and then pulling it back in the opposite direction. Can be located in the form of.

Therefore, when the cable 11 is installed, the fixing end side of the cable 11 can be stopped or waterproofed in a substantially complete state by the elastic material 10 and the water blocking agent 16.

A second embodiment is shown in FIGS. The second embodiment is characterized in that a tubular O-ring is used as the elastic material 10. That is, a ring-shaped recess 17 is provided in the through hole 14 provided in the spacer 9 along the circumferential direction, and the O-ring 10a is housed in the recess 17, and the O-ring 10a is attached to the outer peripheral surface of the cable 11. It is designed to be pressed against.

In this case, the inner diameter of the through hole 14 provided in the spacer 9 is made larger than the outer diameter of the cable 11 as in the above-mentioned embodiment, and the through hole 14 has
A recess 17 is formed between adjacent spacers 9. Then, one recess 17 is formed for each through hole 14, and one O ring 10a is disposed in each through hole.

That is, in a plurality of (three) spacers 9, the through holes 14 provided in the respective spacers are provided relatively close to each other, so that If the recesses 17 are provided for the respective through holes of each pacer, all the recesses will be connected, and the substantially established recesses will not be formed.

Therefore, in each spacer, recesses are not formed in adjacent through holes, for example, recesses are formed every other space or every two spaces, and a combination of three spacers is formed. Thus, one through hole 14 that communicates with each other has one recess 17 and one O-ring 10a is provided.

The O-ring 10a provided in the recess 17 is
The diameter of the central hole facing the through hole 14 is approximately 15 to 16 mm, which is smaller than the outer diameter (18 mm) of the cable 11.

Then, by the same means as in the above embodiment,
By inserting the cable 11 into each through hole 14, the O-ring 10a is expanded and inserted into each through hole 14,
The O-ring 10a is strongly pressed on the side of the recess 17 by the amount of the push-out, and as a result, the inserted cable 11 is pressed against the outer peripheral surface due to the presence of the O-ring 10a, so that the O-ring 10a is tight and waterproof. Is held in.

Further, by applying a waterproofing agent 16 such as grease to a part of the insertion end side of the cable 11 to be inserted, not only the O-ring 10a can be easily passed, but also the O-ring is used as a ladder. The water blocking agent 16 thus collected is collected in the through holes 14, and the water blocking effect is further improved.

In any of the embodiments, fixing the cable 11 in the fixing portion 4 prevents the bare wire portion 11b of the cable 11 from rusting, and the protection tube 8 provided in the fixing portion of the cable is By simply inserting the cable, the cable 11 and the protective tube 8 are joined in a waterproof state, and the length of the bare wire portion 11b is equal to the protective tube 8
The length of the sheath can be made to correspond substantially, and the stripping length of the sheath and its precision are not required. Needless to say, an appropriate filler may be filled in the protective tube 8 after the cable 11 is installed.

[0037]

As described above, the method of preventing rust in the fixing portion of the erection cable according to the present invention is the protective tube for protecting the fixing portion side of the cable in the fixing portion of the erection cable supporting the cable-stayed bridge or the like. And a spacer provided with a through hole for maintaining the arrangement of the cables on the free end side of the protection tube, and an elastic material is provided in the through hole of the spacer so that the spacer is pressed against the inserted cable. As a result, the cable to be erected can be installed by simply inserting it from the free end side of the protective tube according to the arrangement order, and the water between the inserted cable and the protective tube can be stopped almost completely. Alternatively, it is possible to achieve waterproofing, and there is an excellent effect that workability is significantly improved.

Further, a plurality of spacers are arranged adjacent to each other, and an elastic material is arranged between the spacers. The elastic material has a plate shape and is positioned at a position corresponding to the through hole of the spacer. By providing a through-hole with a diameter smaller than the outer diameter of the cable, and the elastic material having an O-ring shape and having an inner diameter smaller than the outer diameter of the spacer, the adhesion with the cable is further improved. It has a strong effect, and has an excellent effect that it is possible to achieve almost complete waterproofing and waterproofing.

Further, by applying a waterproofing agent to a part of the cable and filling at least a part of the through hole of the spacer with the waterproofing agent, the waterproofing and waterproofing action is further improved. It has an excellent effect.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view schematically showing an example of a fixing portion of an erection cable to which a rustproofing method according to a first embodiment of the present invention is applied.

FIG. 2 is an enlarged cross-sectional view showing only a main part of a rust preventive mechanism in the embodiment.

FIG. 3 is a side view schematically showing the fixing end side of the erection cable in the embodiment.

FIG. 4 is a schematic enlarged cross-sectional view for explaining a situation in which the erection cable in the embodiment is inserted into a rust preventive mechanism.

FIG. 5 is a schematic enlarged cross-sectional view of a main part to which a second embodiment according to the present invention is applied.

FIG. 6 is a cross-sectional view showing, in an enlarged manner, only a main part of a rust preventive mechanism in the embodiment.

FIG. 7 is a schematic enlarged cross-sectional view for explaining a situation in which the erection cable in the embodiment is inserted into a rust preventive mechanism.

[Explanation of symbols] 1 Main girder 2 Cable fixing through hole 3 Outer tube 4 Fixing member 5 Fixing plate 6 Supporting member 7 Fixing block 8 Protective tube 8a Adapter 9 Spacer 10 Elastic body 10a O-ring 11 Cable 11a Sheath Part 11b Bare wire part 12 Wedge material 13 Bolts 14,15 Through hole 16 Water blocking agent 17 Recessed part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akiyoshi Suzuki 12-2 Nibancho, Chiyoda-ku, Tokyo Esu Co., Ltd. (72) Inventor Wataru Ohashi 12-12 Nibancho, Chiyoda-ku, Tokyo Esu Co., Ltd. (72) Inventor Kenji Wako 12-2 Nibancho, Chiyoda-ku, Tokyo Esu Co., Ltd. (72) Inventor Masamitsu Takei 1 Niihamacho, Chuo-ku, Chiba-shi, Chiba Kawatetsu Techno Wire Co., Ltd. (72) Inventor Shoji Shigeo, 1 Shinhamacho, Chuo-ku, Chiba-shi, Chiba, Kawakawa Techno Wire Co., Ltd. Tokuni Tokyo 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel Co., Ltd. Tokyo head office (72) Inventor Shigeki Nakamura Chiyoda-ku, Tokyo Town 2-chome No. 2 No. 3 Kawasaki Steel Corporation of Tokyo in the head office

Claims (5)

[Claims] 1. A fixing tube for a cable that supports a cable-stayed bridge or the like is provided with a protection tube for protecting the fixing section side of the cable, and a through hole for maintaining the arrangement of the cables is provided on the free end side of the protection tube. A rust preventive treatment method in a fixing portion of a erected cable, characterized in that a spacer is provided, and an elastic material is provided in a through hole of the spacer to make pressure contact with a cable to be inserted. 2. A plurality of spacers are arranged adjacent to each other,
The method for preventing rust in a fixing portion of an erection cable according to claim 1, wherein an elastic material is arranged between the spacers. 3. The rust preventive for a erected cable according to claim 1, wherein the elastic material is plate-shaped, and a through hole having a diameter smaller than an outer diameter of the cable is provided at a position corresponding to the through hole of the spacer. Processing method. 4. The rust preventive treatment method for a erected cable according to claim 1, wherein the elastic material has an O-ring shape, and the inner diameter of the O-ring is smaller than the outer diameter of the spacer. 5. The rust preventive treatment method for a erected cable according to claim 1, wherein at least a part of the through hole of the spacer is filled with a water blocking agent.