JPH049881B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is applicable to cables for cable-stayed bridges, suspension members for suspended roof structures, tension fixing of tension members for offshore structures and other structures. The present invention relates to a method and a fixing device thereof.

(Prior Art) Known methods and devices for tensioning stay cables used in recent large cable-stayed bridges and tension members of other offshore structures are shown in Fig. 7. There is something shown in

This is a method in which an installation steel pipe 1', which is pre-equipped with a vibration isolating member 11' such as anti-vibration rubber, is installed on the main pillar n or main girder m, and the diagonal cable 3 is inserted into the installation steel pipe 1' and fixed under tension. It was hot.

(Problems to be Solved by the Invention) However, in the method of fixing the diagonal cable and its fixing device in the above-mentioned prior art, the diagonal cable is installed in an installed steel pipe provided with a vibration isolating member such as vibration isolating rubber in advance. When the diagonal cable is inserted and tension-fixed, due to its own weight and external factors such as wind, the cables are tension-fixed with their cores shifted from each other, that is, with the diagonal cable biased toward one side of the installation steel pipe. It becomes difficult to align the central axis of the steel pipe and the central axis of the diagonal cable, and it is not possible to provide vibration isolation and absorption at the tip of the installed steel pipe, which is subject to the most vibrational load on the diagonal cable, and the vibration of the diagonal cable increases. This caused the disadvantage that the vibration isolating member within the installed steel pipe was displaced and moved, resulting in damage to the diagonal cable in this area.

Furthermore, it is not possible with conventional diagonal cable fixing methods and fixing devices to align the central axes of these diagonal cables and the central axes of the installed steel pipes during construction and adjust the misalignment during the work process. It was possible.

The present invention overcomes the drawbacks of the conventional diagonal cable fixing method and fixing device as described above, and
The purpose of this is to provide a method and device for fixing diagonal cables that have new functions and effects, and when the diagonal cable is tensioned and fixed, the center axis of the diagonal cable and the center axis of the installed steel pipe are aligned. The purpose of this is to align the center of the shaft to ensure its vibration-proofing and vibration-absorbing effects. And, even if there is a misalignment in which the center axes of the installed steel pipe and the diagonal cable do not match each other when tensioning and fixing the diagonal cable, it is possible to easily adjust and align the centers. It is.

In addition, this diagonal cable fixing method and fixing device prevent the vibration isolating member from shifting or moving within the installed steel pipe, and even if vibrations are applied to the diagonal cable due to external factors, they can be effectively suppressed. We provide stay cables that are safe, durable, and can withstand long-term use by absorbing or isolating vibrations to prevent fatigue and damage to stay cables, and reduce the load burden, as well as preventing accidents caused by stay cables. This is what we are trying to achieve.

(Means for solving the problems) The means of the present invention for achieving the above-mentioned object are as follows:
In a tension fixing method for a stay cable in which a stay cable is tension-fixed across a main column and a main girder of a cable-stayed bridge, a vibration isolator is attached to the end of an installation steel pipe provided on the main column and the main girder. At the same time as temporary installation, after inserting the diagonal cable through the installation steel pipe and the vibration isolator and fixing it under tension, align the center axis of the diagonal cable and the center axis of the vibration isolator, A method for fixing a stay cable, characterized in that the vibration isolator is tightly fixed to an end of an installation steel pipe, and both ends of the stay cable are tension-fixed across a main column and a main girder of a cable-stayed bridge. In a tension fixing device consisting of an installation steel pipe inserted and fixed into the installation steel pipe and a vibration isolating member provided within the installation steel pipe, a vibration isolator is movably provided on a mounting plate provided at one end of the installation steel pipe. In the diagonal cable fixing device, the vibration isolator is comprised of a cylindrical body through which the diagonal cable is inserted, and plates provided at both ends of the cylindrical body.

(Function) According to the above configuration, when tension-fixing the diagonal cable, first, fixing tools such as bolts are provided on the mounting plate of the installation steel pipe in advance, and the vibration isolator is temporarily attached using the fixing tools. In this state, the diagonal cable is inserted into the installation steel pipe and the vibration isolator and fixed under tension, and then the vibration isolator is movably adjusted to align the central axis of the diagonal cable with the central axis of the cylinder in the vibration isolator. Align to match.

After that, the vibration isolator is fixed to the mounting plate by tightening the bolts and other fittings.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

The method and device for fixing stay cables of the present invention are used for cable-stayed bridges, suspended roof structures, marine structures, etc., but in the embodiment of the present invention, a set of three cables is used for cable-stayed bridges. We will explain the case where this is done.

The stay cable anchoring device A (hereinafter simply referred to as the anchoring device) is installed on both sides of the main girder m and the main column n of the cable-stayed bridge S.
It is composed of an installation steel pipe 1 and a vibration isolator 2 provided above and below.

The installation steel pipe 1 has three steel pipes 4 having a diameter larger than the diagonal cable 3, which are open at both ends, and each having an inlet 1a on one end of the circumference and an outlet 1b on the other end of the circumference. It consists of an anchor plate 5 and a mounting plate 6 attached to both the upper and lower ends of the steel pipe 4, and the end of the diagonal cable 3 is inserted into the steel pipe 4, and its end is attached to the fixing end fitting 3a with a fixing nut. 3b is fixed to the anchor plate 5 by screwing, and the cap 3c is covered.

The steel pipe 4 and the cap 3c are filled with a rust preventive material a such as urethane injected from the injection ports 1a and 3d.

Further, an arbitrary number of mounting bolts 8 are provided upright at arbitrary locations on the mounting plate 6 at the upper end of the steel pipe 4, and the vibration isolator 2 is fixed via the mounting bolts.

The diagonal cable 3 is formed by bundling a large number of strands g and covering the outer periphery with a synthetic resin sheathing material h. A terminal fitting 3a for tension fixation is attached to each of the sections.

As shown in Fig. 1, at the construction site, this diagonal cable 3 is wound into a reel and set on a bobbin b placed on the main girder m. The top of the roller c is pulled out with a winch d, and is erected across the main girder m and the main column n, and both ends thereof are inserted into the fixing device A provided on the main girder m and the main column n and tensioned. It will be established. The number of diagonal cables 3 is not limited to three, but more than three diagonal cables may be bundled and installed, but in this embodiment, three diagonal cables are used.

The vibration isolator 2 includes a cylindrical body 9 that is open at both upper and lower ends similarly to the installation steel pipe 1, upper and lower plates 10a and 10b provided at both the upper and lower ends of the cylindrical body 9, and is fitted into the cylindrical body 9. and a vibration isolating member 11,
Both upper and lower ends of the cylinder 9 are connected to upper and lower plates 10a, 1.
They are formed to fit into fitting holes 10'a and 10'b opened in 0b, respectively.

Further, a fitting hole 12 having a larger diameter than the bolt 8 is bored in the lower plate 10b of the vibration isolator 2 at a location corresponding to the mounting bolt 8 of the mounting plate 6.

The fitting hole 12 has a size that allows the vibration isolator 2 to move in any direction on the mounting plate 6 when the mounting bolt 8 is loosely inserted, so by moving the vibration isolator 2, the vibration isolator 2 can be moved in any direction. Alignment with material cable 3,
That is, the center axis of the diagonal cable 3 and the center axis of the cylinder 9 of the vibration isolator 2 can be easily aligned.

This means that even if the diagonal cable 3 is inserted into the installed steel pipe 1 with its center misaligned, the diagonal cable 3 can be finely adjusted by moving the vibration isolator 2 at the end of the installed steel pipe 1. This allows alignment with the cable 3.

Therefore, at the ends of the installed steel pipes 1 at the main girder m and the main column n, the vibration isolators 2 and the diagonal cables 3 are aligned, that is, the diagonal is made with their central axes completely aligned. The material cable 3 is fixed under tension.

Incidentally, the above-mentioned fitting holes 12 are not formed in the places corresponding to the mounting bolts 8, but are bored in arbitrary places, and the vibration isolator 1
2 may be temporarily installed by inserting the mounting bolt 8 into a corresponding arbitrary fitting hole 12.

Further, a primary washer 13 and a secondary washer 14 are fitted into the stepped portion 12a at the upper part of the fitting hole 12, and the primary washer 13 has an oblong bolt insertion hole 13a extending in an arbitrary direction from the center.
As shown in Fig. 4, the mounting bolt 8 is inserted into the fitting hole 12.
It can be inserted anywhere in the throat. Further, the primary washer 14 covers the bolt insertion hole 13a remaining after the mounting bolt 8 is inserted,
The insertion hole 14 is bored at an eccentric position, that is, at approximately the same position as the end of the bolt insertion hole 13a.

Therefore, the mounting bolt 8 is inserted into the bolt insertion hole 13.
Remaining bolt insertion hole 1 no matter where it is located in a
3a can be blocked. Note that the vibration isolator 2 is not limited to being fixed by the mounting bolts 8, but may be fixed by welding or other methods after centering by movable adjustment.

As shown in FIG. 6, the vibration isolating member 11 includes a semicircular and flat stopper 15, a cylindrical rubber ring 16 made of chloroprene rubber that is cut at one point, and expandable from the cut portion 16a, and a semicircular and flat stopper 15. The stopper 15 is placed on a protrusion 9a at the inner bottom of the cylinder 9, and a rubber ring 16 whose inner surface is coated with adhesive is placed on the stopper 15.
A cover plate 17 covering the rubber ring 16 is fixed to the upper surface of the cylindrical body 9 with a tightening bolt 17a.

Next, a method for fixing the diagonal cable 3 will be explained.

First, the vibration isolator 2 is temporarily attached to the attachment plate 6 of the installation steel pipe 1 provided on the main girder m and the main column n using attachment bolts 8.

This is to install the steel pipe 4 of the installed steel pipe 1 and the cylindrical body 9 of the vibration isolator 2 with their centers aligned, and at this time the vibration isolator 11 has not yet been fitted into the cylindrical body 9.

Next, the diagonal cable 3 is connected to the cylinder body 9 of the vibration isolator 2 and the installed steel pipe 1 by a pilot wire attached to the lower end of the diagonal cable 3 via a coupler.
A terminal tool 3 for tension fixing, which is inserted into the
By screwing the fixing nut 3b into the anchor plate 5, the anchor plate 5 is fixedly attached to the anchor plate 5, and is constructed between the main girder m and the main pillar n.

Then, the diagonal cable 3 is tension-fixed by tensioning it with a tension jack on the main girder m side or the main pillar n side, and the cap 3c is crowned on the end of the tension-fixing terminal 3a, and the cap 3c and A rust preventive material a such as urethane is injected into the steel pipe 4 of the installed steel pipe 1 through the injection ports 3d and 1a, respectively.

Finally, the diagonal cable 3 that has passed through the installed steel pipe 1 and the vibration isolator 2 is aligned with the vibration isolator 2, that is, the central axis of the diagonal cable 3 and the cylindrical body of the vibration isolator 2 are aligned. Match the center axis of 9.

To do this, first, the mounting bolts 8 are loosened to allow the vibration isolator 2 to move within the fitting hole 12.

Then, with the vibration isolator 2 movably adjusted so that the center axis of each cylinder 9 and the center axis of each diagonal cable 3 are aligned, the mounting bolts 8 are tightened again to completely remove the vibration isolator 2. stick.

Next, the stopper 15 is inserted into the cylinder 9, and the rubber ring 16 whose inner surface is coated with adhesive is fitted.

At this time, since the cylinder body 9 and the diagonal cable 3 are aligned, the rubber ring 16 can be easily fitted into the gap 18 between the cylinder body 9 and the diagonal cable 3, thereby preventing the rubber ring 16 from being misaligned or displaced. can.

Finally, the cover plate 17 is attached to the upper surface of the cylindrical body 9 using the tightening bolts 17a to complete the fixing operation.

(Effects of the Invention) The present invention has the following effects by having the above configuration.

By providing a movable vibration isolator at the end of the installed steel pipe, it is possible to center the diagonal cable and the vibration isolator, that is, to align their respective central axes. The vibration isolation and vibration absorption effects of the end portion can be enhanced.

A vibration isolator is temporarily attached to the end of the installed steel pipe, and after the diagonal cable is inserted through the installed steel pipe and the vibration isolator and fixed under tension, the center of the diagonal cable is adjusted by movably adjusting the vibration isolator. In a state where the shaft and the central axis of the vibration isolator are aligned, the vibration isolator can be closely fixed to the end of the installed steel pipe to facilitate alignment between the diagonal cable and the installed steel pipe. This makes it possible to prevent the position of the vibration isolators from shifting, and even if the diagonal cable is subjected to vibrations caused by wind, earthquakes, etc. or other external factors, it is possible to effectively prevent and absorb vibrations. It is possible to reduce the load on the stay cable, prevent fatigue and damage, and provide a stay cable that is highly durable and can withstand long-term use.

[Brief explanation of drawings]

Fig. 1 is a front view of the cable-stayed bridge, Fig. 2 is a longitudinal sectional side view of the stay cable fixing device of the present invention, Fig. 3 is a longitudinal sectional side view of the vibration isolator, and Fig. 4 is a plan view of the same. 5 is a perspective view of the same, FIG. 6 is a perspective view of a vibration isolating member, and FIG. 7 is a longitudinal sectional view of a conventional fixing device. S... Cable-stayed bridge, A... Anchoring device for stay cables, m... Main girder, n... Main column, 1... Installation steel pipe, 2... Vibration isolator, 3... Stay cable, 6 ……
Mounting plate, 9... Cylindrical body, 10a, 10b...
plate.

Claims (1)

[Scope of Claims] 1. A method for tension-fixing a diagonal cable across a main column and a main girder of a cable-stayed bridge, in which an installation steel pipe provided on the main column and main girder is At the same time as temporarily attaching a vibration isolator to the end, the diagonal cable is inserted through the installed steel pipe and the vibration isolator and fixed under tension, and then the vibration isolator is moved to connect the central axis of the diagonal cable to the vibration isolator. A method for fixing a diagonal cable, characterized in that the vibration isolator is closely fixed to an end of an installation steel pipe by aligning the center axis of the cable to match the center axis of the body. 2. A tension fixing device consisting of an installation steel pipe that is inserted and fixed to both ends of a diagonal cable that is tensioned and fixed across the main pillar and main girder of a cable-stayed bridge, and a vibration isolating member provided within the installation steel pipe. A vibration isolator is movably provided on a mounting plate provided at one end of the installation steel pipe, and the vibration isolator is provided at a cylindrical body through which the diagonal cable is inserted, and at both ends of the cylindrical body. A diagonal cable fixing device comprising: