JPS5919232B2 - Construction method of tower-like structure using unbonded PC steel wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of constructing a tower-like structure using unbonded PC steel wire.

When introducing prestress into a tower-like structure such as a silo using unbonded PC steel wires, it is necessary to arrange the unbonded PC steel wires in the circumferential direction of the side walls when constructing the side walls.

However, when constructing from the bottom upwards using a sliding formwork or the like, the vertical and horizontal reinforcement becomes a hindrance, making the reinforcement work complicated.

An object of the present invention is to provide a method for constructing a tower-like structure that allows a series of operations related to the installation of unbonded PC steel wires to be carried out safely and efficiently.

In the construction method of this invention, first, the unbonded PC steel wire to be arranged is fed into a guide rail that is attached in advance to the lower surface of the yoke horizontal member of the sliding formwork.

This guide rail is made of C channel material or the like and has a groove for temporarily holding the PC steel wire.

The unbonded PC steel wire slides along the groove of this guide rail, and when it has been sent out a predetermined length, it is lowered onto a banger that has been previously installed at a placement position.

The unbonded PC steel wire is lowered by using a notch provided at the lower intermediate position of the guide rail.

At this time, since the unbonded PC steel wire can be fed along the guide rail from one location, the vertical and horizontal reinforcement of the side wall does not become an obstacle.

In this way, the unbonded PC steel wire is arranged, and the tower-like structure is constructed while concrete is poured and cured in accordance with the upward sliding of the sliding formwork.

In order to make an unbonded PC steel wire, the PC steel wire must be coated with a material such as asphalt to prevent adhesion to concrete, or the PC steel wire must be inserted into the sheath and the sheath and PC steel wire must be bonded together. There is a method of filling the gap with grease or the like.

FIG. 1 shows an example of the arrangement in which the unbonded PC steel wire 1 is used in a group silo A in which a plurality of silos are integrated by a part of their side walls and connected together.

The length of the unbonded PC steel wire 1 is determined from the viewpoint of workability and introduction of prestress.

It is desirable that the unbonded PC steel wires 1 be arranged between the longitudinal reinforcements of the concrete cylinder, and that the anchoring parts 2 be arranged alternately.

Further, the interval between the silos in the height direction is about 40 crfL to 100 cm.

Figures 2 to 7 show embodiments of the present invention, and Figure 2 shows how the guide rail 6 is attached to the lower surface of the yoke horizontal member 4 of the sliding formwork 3 and the unbonded PC steel wire 1 is arranged. It shows how it is done.

As shown in FIG. 3, the guide rail 6 is constructed using a C-shaped channel material or other material having a groove 15 (see FIG. 8) for sliding and temporarily holding the unbonded PC steel wire 1. Attach the entire circumference of the side wall of the object or the required section.

Therefore, it will be installed across a plurality of sliding formworks 3.

Further, a notch 7 is provided at a predetermined location in the lower part of the guide rail 6 for pulling down the unbonded PC steel wire 1 when the unbonded PC steel wire 1 is lowered.

During construction, the unbonded PC steel wire 1 is first set on the guide rail 6 described above.

The unbonded PC steel wire 1 is set from one place on the guide rail 6, and is fed in such a way that it slides along the guide rail 6.

This work can be done manually, but if necessary, a bobbin or the like can be used to increase efficiency.

Further, as shown in FIG. 3, if a pilot cap 12 is attached to the tip of the unbonded PC steel wire 1, the unbonded PC steel wire 1 can be fed smoothly.

Next, the unbonded PC steel wire 1 temporarily held on the guide rail 6 as described above is lowered to a predetermined installation position.

At this time, a simple withdrawal hook 1 as shown in Fig.
4, the unbonded PC steel wire 1 can be easily pulled down from the notch 7.

Then, the unbonded PC steel wire 1 that has been pulled down falls onto the banger 10 attached to the reinforcement of the side wall, and is settled in a predetermined arrangement position.

Figures 4a, b, and c each show examples of different types of bangers 10, in which 10a has a rod 11 arranged in the center of the side wall,
The bangers 10, 10 are of the type to which hooks fixed with wing nuts are attached, and the bangers also serve as width-stop reinforcing bars for side wall reinforcement.

This invention has the above-mentioned configuration, and by attaching a guide rail of a simple structure such as a C-shaped channel material to a sliding formwork, an unbonded PC steel wire is fed out from one place along the groove of the guide rail and arranged. is possible,
Work becomes easier.

Furthermore, since the unbonded PC steel wire temporarily held on the guide rail is lowered using the notch provided in the guide rail, there is little need to correct misalignment or slack.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an example of a tower-like structure using the construction method of the present invention, Fig. 2 is a longitudinal sectional view in the circumferential direction of the side wall showing an outline of the construction method, and Fig. 3 is a cross-sectional view of the guide rail. Perspective view, 4th
Figures a, b, and c are front views showing various examples of bangers, Figures 5 a and b are perspective views of the cutout portion of the guide rail, and Figure 6 shows how the unbonded PC steel wire is drawn down. FIG. 7 is a perspective view showing the arrangement position of the unbonded PC steel wire, and FIG. 8 is a longitudinal sectional view of the guide rail. A... Group silo, 1... Unbonded P
C steel wire, 2...Fixing part, 3...Sliding formwork, 4...Yoke horizontal material, 5...
...Weir plate, 6... Guide rail, 7...
... Notch, 8... Horizontal stripe, 9... Vertical stripe, 10.10a t 1 ob , 10c"" banger, 11... Rod, 12... ... Pilot cap, 13 ... Joint plate, 14 ...
...Drawing hook, 15... Groove.

Claims (1)

[Claims] I. A guide rail having a groove for temporarily holding the PC steel wire is attached to the lower surface of the yoke horizontal member of the sliding formwork, and the unbonded PC steel wire is fed out along the groove of the guide rail to a predetermined length. After sliding, the unbonded PC steel wire set in the groove of the guide rail is pulled down from the notch provided at a predetermined position in the middle lower part of the guide rail, and the banger set in advance at the PC steel wire placement position is pulled down. A method for constructing a tower-like structure using unbonded PC steel wires, which is characterized by lowering the unbonded PC steel wires and placing the unbonded PC steel wires, and sequentially pouring concrete. 2. A method for constructing a tower-like structure using unbonded PC steel wire according to claim 1, in which the guide rail is made of C-shaped channel material.