JPS5828004Y2 - Lifting device for suspended structures - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a suspension device for suspending a suspended object in a suspended structure such as a suspension bridge or a suspended floor.

Suspension devices using wire ropes in this type of suspended structure are comprised of one or more wire ropes per load point.

This wire rope is generally twisted with an S twist or a Z twist, and in either of these twisted ropes, when tension is applied due to a load, a rotational torque in the direction of untwisting, that is, an autorotation force is applied. We are prepared.

Therefore, with conventional lifting devices that are constructed using a single type of wire rope, either S-twist or Z-twist, if the rotation of the load end is not restrained during erection, the load end will rotate, causing problems during the erection work. Not only was this a nuisance, but it was also a safety issue.

Therefore, the present invention provides a suspension device for a suspended structure that can reliably prevent the rotation of the suspension body due to the rotation of the wire rope and improve the efficiency and safety of the work of erecting the suspended structure. That is.

The feature of the present invention is that it is a suspension device in a suspension structure for suspending a suspended object below a load support. The Z-twisted rope and the S-twisted rope are arranged symmetrically, and the load is equally distributed between the load support and the suspended object. The present invention relates to a suspension device for a suspension structure configured to prevent rotation of a suspended object due to the rotational torque of a wire rope by being installed between the wire rope and the wire rope.

Embodiments of the present invention will be described below with reference to the drawings.

1 to 3 show an embodiment in which the present invention is applied to a hanger rope device for a suspension bridge.

The figure shows the main points of a suspension bridge, where 1 is a main cable (main rope) as a load support, 2 and 3 are hanger ropes forming a hanger rope device, and 4 is a bridge chord member as a suspended object.

One of the two hanger ropes 2 and 3 mentioned above 2
is a Z-twisted rope, and the other rope 3 is an S-twisted rope, and by hanging both ropes 2 and 3 in a U-shape around the main cable 1, a total of four ropes 2a and 2b are used.
, 3 a , and 3 b have rope hooks as structures.

In this way, if a hanger rope device is configured with two ropes 2 a and 2 b and two ropes 3 a and 3 b with Z twist, S twist, and two ropes twisted in opposite directions, the ropes will be twisted by the load as shown in Fig. 3. Since the rotation forces F acting individually cancel each other out between the two types of ropes, the rotation ability of the device as a whole in a specific direction is completely eliminated, thereby preventing the bridge chord members 4 from rotating.

In addition, in the embodiment shown in FIG.
It is constructed by combining one twisted rope 10a and one Z twisted rope 10b.

Reference numeral 11 denotes a joist as a suspended object.

By doing this, as in the case of the first embodiment, it is possible to prevent the rotation of the entire hanging member 10 and the rotation of the joist beam 11, so that the work of constructing the suspended floor can be carried out efficiently and safely. becomes.

In order to achieve the original purpose of the lifting device of the present invention as described above, it is necessary to use both S-twisted and Z-twisted ropes to balance the rotational torque of the wire rope ropes that make up the lifting device during erection. It is necessary to share the load with the

Two sides of the means are shown in FIGS. 5 and 6.

In FIG. 5, 12 is a Z-twisted rope, 13 is an S-twisted rope, and an equalizer rope 15 is tied to both ropes 12.13 via a clamp fitting 14.14, and a load is applied to this via an equalizer sheave 16. Multiply by W.

In this case, in order to prevent the torque of the equalizer rope 15 from adversely affecting the S-Z twisted rope system,
The length of the rope 15 is kept to the necessary minimum.

Alternatively, it is more preferable to use a non-rotating rope as the equalizer rope 15.

Further, the means shown in FIG. 6 includes both Z-twisted and S-twisted ropes 12.
13 are joined together by a clamp fitting 17, and a load W is applied to the fitting 17.

Furthermore, FIG. 7 shows a more specific example in which such means is incorporated into a hoisting system using a crane or the like to carry out erection work.

That is, intermediate clamp fittings 14, 14 and tip sockets 18 and 18 are provided on the Z-twisted rope 12 and S-twisted rope 13 suspended from the main cable 1, and the intermediate clamp fittings 1
4.14 is equipped with an equalizer rope 15 and an equalizer sheave 16.

19 is a girder as a suspended object. First, the girder 19 is suspended using the crane 20, and then the girder 19 is hung on the equalizer sheave 16 using the hanging wire 21.

After removing the crane 20 as shown in 2, the jacking system 22 is mounted on the intermediate clamp fitting 14.14 as shown in E, and the girder 19 can be placed in the socket 18.18 by jacking it up as shown in E.

Finally, by removing the jacking system 22 and the interlocking clamp fittings 14 and 14 as shown in (G), the girder lifting work is completed.

Next, the results of performance tests of the suspension device according to the present invention and the conventional suspension device will be shown.

That is, a conventional lifting device consisting of two Z-twisted ropes,
Regarding the hanging device of the present invention, which consists of one Z-twisted rope and one S-twisted rope, the lifting device with a length of 7 m is hung with a hoist and a weight is attached to the lower end. 10
Experiments were conducted in two cases: 0 mm and 200 mm.

The rope material used was IWRC6X Fi (29) C
JIS No. 18] Z-twist and S-twist.

Then, a weight of up to 1000 kg was applied, and changes in the rotation angle and rotation torque due to the load were measured, and the results shown in FIGS. 8 and 9 were obtained.

In the figure, ml is the suspension device of the present invention, and m2 is the conventional suspension device.

As can be seen from both figures, the suspension device of the present invention showed excellent performance in both rotation angle and rotation torque, which is completely incomparable to the conventional device.

In particular, at the rotation angle shown in Figure 8, rope entanglement (point X in Figure 8) occurs under a load of approximately 200 kg using conventional equipment, and the erection work becomes extremely difficult unless the loaded end is restrained. With the device of the present invention, not only the entanglement phenomenon of the rope but also the rotation itself is almost eliminated, making the erection work extremely efficient.

As described above, according to the suspension device of the present invention, the rotation canceling effect of the wire ropes that make up the device can be obtained,
As a result, reliable non-rotability can be obtained as a whole of the device.

Therefore, rotation of the suspended object can be reliably prevented, and the efficiency and safety of the erection work can be improved.

In particular, according to the present invention, the wire rope itself has
Since there is no need to perform any processing and the existing S-twisted and Z-twisted ropes can be used as they are, it is very advantageous in terms of cost and handling.

[Brief explanation of the drawing]

Figure 1 is a side view showing an embodiment in which the present invention is applied to a hanger rope in a suspension bridge structure, Figure 2 is a front view of the same, and Figure 3 is a front view of the same.
Figure 4 is a cross-sectional view showing an example in which the present invention is applied to a suspension wire of a Joyce beam in a suspended floor structure, and Figures 5 and 6 show how the load is applied evenly to the wire ropes that make up the device. A front view showing two sides of the means for sharing;
FIG. 7 is an explanatory diagram showing the case where the same means is utilized in a hoisting system using a crane, and FIGS. 8 and 9 are graphs showing the performance ratios of the device of the present invention and the conventional device based on experiments. 2.2a, 2b...Z twisted rope, 3, 3a, 3
b... S twisted rope, 5, 7... S twisted rope, 6, 8... Z twisted rope, 10 a...
...S twisted rope, 10 b...Z twisted rope,
12...Z-twisted rope, 13...S-twisted rope.

Claims (1)

[Scope of utility model registration request] This is a suspension device for a hanging structure for suspending a suspended object below a load support, and consists of an even number of wire ropes, half of which are Z-twisted ropes and the other half are S-twisted ropes. By installing the Z-twisted rope and S-twisted rope between the load support and the suspended object in a symmetrical arrangement and with the load equally distributed between them, the wire rope can rotate on its own axis. A suspension device for a suspended structure, characterized in that it is configured to prevent rotation of a suspended object due to torque.