JPH06298487A - Hoisting jig for precast concrete mold and method for hoisting precast concrete mold - Google Patents

Abstract

PURPOSE:To provide a hoisting jig by means of which a precast concrete mold temporarily laid on its side is safely hoisted so that an operation for plumbing the precast concrete mold can be performed with efficiency. CONSTITUTION:A hoisting jig includes a hanging beam 9, a plurality of anchored blocks 10... each secured to the hanging beam 9, a wire 11 wound to each of the anchored block 10..., and a plurality of running blocks 12... each suspended by means of the wire 11, and the wire 11 is wound to each of the anchored blocks 10... and to each of the running blocks 12... so that the running blocks 12... are allowed to freely go up and down relative to the anchored blocks 11..., and each of the running blocks 12... is provided with an engagement jig 12e to be engaged with a precast mold 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hoisting jig for precast concrete formwork used when hoisting a precast concrete formwork and a method for hoisting the precast formwork using the jig.

[0002]

2. Description of the Related Art As is well known, in the construction of columns for building structures, there is a shortage of workers in recent years, prolongation of work by assembling and disassembling dams for formwork, and reduction of the amount of dams used. In consideration of the environmental issues and the like, the precast concrete formwork (hereinafter simply referred to as "precast formwork") integrally formed in a tubular shape so as to form the side surface of the pillar to be constructed. Is used.

The construction of columns using this precast formwork is performed by the following main steps. (1) The precast formwork is hoisted by a lifting machine, and a column steel frame, a column main bar, which is built in the work floor in advance,
The reinforcing material, such as a hoop streak, is built up from the upper side so as to enclose the reinforcing material and erected. (2) In order to prevent the displacement of the precast formwork during subsequent concrete pouring, adjust the standing position using a pipe support fixed to the work floor or an upright support member such as a support chain. Fix the posture. (3) Concrete is cast in the precast mold whose posture is fixed, and a column in which the precast mold and the cast concrete are integrated is constructed.

By the way, when the precast formwork in the above step (1) is suspended by lifting and built around the reinforcing material, the precast is temporarily placed on the work floor or in a stockyard in the work site in a laid state. Work that causes the formwork is required. As shown in FIG. 6, this raising work is performed by the plate portion 1 of the hanging metal fitting 1 made of mountain steel having a predetermined length.
a is abutted at the upper and lower ends of side walls 2a, 2a of the temporarily placed precast formwork 2 which are opposed to each other in the horizontal direction, and fixed by fasteners 3 composed of bolts and nuts. The shackle 5 is attached to the hole 4 provided at the upper end of the plate portion 1b of No. 1, and the hook 7 at one end of the suspension wire 6 is hooked on each shackle 5, and the other end of the suspension wire 7 is placed at a predetermined position (not shown). ) And it was hoisted by a lifting machine (not shown), and the other end of the precast formwork where the hanging metal fitting 1 was not attached was used as a fulcrum.

[0005]

However, there are the following problems in the work of causing the above-mentioned conventional precast formwork. That is, since the precast formwork 2 is lifted by independently hooking the hook 5 of the hanging wire 6 to the hanging metal fitting 1 fixed to the precast formwork 2, from the initial stage of lifting up to the time of standing vertically, the suspension fixed to the lower side. The load of the precast mold 2 is applied only to the hanging wires 6 hooked on the metal fitting 1. That is, as shown in FIG. 7, the suspension wires 6, 6 hooked on the upper suspension fittings 1, 1 are loosened, and the load is concentrated on the suspension wires 6, 6 hooked on the lower suspension fittings 1, 1. Because it will
The load of the precast formwork 2 was concentrated on the fixed parts of the lower metal fittings 1 and 1, and there was a risk of damage.

In particular, the precast formwork 2 temporarily placed on the work floor or the like may not be accurately kept in a horizontal state, and in the initial stage of lifting, the precast formwork 2 is attached to one place where the hanging metal fitting 1 is attached. The full load will be applied,
The risk of breakage was very high. Therefore, in order to avoid this danger, the lifting work must be performed carefully, and the efficiency of the work of installing the precast formwork 2 must be reduced.

Further, in the above-mentioned raising work, when the hoisting speed is slow, when the other end serving as the fulcrum is separated from the floor surface of the work floor, the precast formwork is moved due to the movement of the center of gravity thereof. 2 may swing like a pendulum, and the lower end of the precast mold 2 that does not serve as a fulcrum may come into contact with the floor surface of the work floor, resulting in damage.

The present invention has been made in view of the above-mentioned problems, and it is possible to safely raise a precast concrete formwork that is temporarily placed in a state of being laid down, without causing damage, so that the precast concrete formwork can be installed. It is an object of the present invention to provide a hoisting jig capable of efficiently performing the above and a hoisting method of a precast concrete formwork using the hoisting jig.

[0009]

A hoisting jig for a precast concrete formwork according to claim 1 of the present invention is a hoisting beam,
A plurality of fixing pulleys fixed to the suspension beam, a wire wound around the plurality of fixing pulleys, and a plurality of moving pulleys suspended around the wire are provided, and the wire includes the plurality of fixing pulleys. The wire is placed in a tensioned state when the moving pulley is hung up and down, and the plurality of moving pulleys are arranged so as to be vertically movable relative to the plurality of fixing pulleys. An engaging jig that engages with the precast concrete formwork is provided below the pulley.

A method of hoisting a precast concrete formwork according to a second aspect of the present invention uses the hoisting jig for the precast concrete formwork according to the first aspect, and the precast is temporarily placed in a laying state in a temporary storage place. The load of the precast concrete formwork is applied to the one end of the concrete formwork by engaging an engaging jig provided on the movable pulley to lift the suspension beam and tension the wire. The precast concrete formwork with the other end of the precast concrete formwork as a fulcrum to lift it upright, and the floor of the temporary storage space and the fulcrum of the other end of the precast concrete formwork. It is characterized in that a cushioning material is interposed between the non-retaining portion.

[0011]

In the invention of claim 1, when the wire is suspended from the plurality of moving sheaves, the wire is in a tensioned state, and the plurality of moving sheaves are different from the plurality of fixing sheaves. Are arranged so as to be vertically movable relative to each other, and when a load is applied to any one of the engaging jigs provided on the plurality of moving pulleys, the fixing pulley is either One of the movable pulleys moves downward, and the engaging jig of any other movable pulley moves upward, so that the wire is not loosened, and a constant tension is always applied.

According to the second aspect of the present invention, the engaging jig attached to the movable pulley is engaged with one end of the precast concrete formwork which is temporarily placed in the temporary storage place in a state of being laid sideways, and the other end is engaged. The precast concrete formwork is lifted upward with the section as a fulcrum and stands up. At this time,
Since the wire wound around the fixing pulley and the moving pulley is always in a tension state without slackening, an equal load is applied to the engaging jig, so that an unbalanced load is applied to the hoisted precast concrete formwork. Never be done.

Further, a cushioning material is interposed between the floor surface of the temporary storage space and a portion which does not serve as a fulcrum of the other end of the precast concrete formwork, and when the precast concrete is lifted up, It is possible to avoid contact between the floor surface and the precast concrete formwork even when a pendulum motion is performed along with the movement.

[0014]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 shows a first embodiment of a suspension jig for precast concrete formwork of the present invention.
The same parts as those of the conventional example shown in FIGS. 6 and 7 are designated by the same reference numerals, and the description thereof will be omitted.

As shown in FIG. 1, a suspension jig 8 for a precast concrete formwork has a substantially cross-shaped suspension beam 9 in plan view.
And a fixed pulley 10 fixed to the lower end of the suspension beam 9 ...
(Fixing pulley), an endless wire 11 wound around the fixed pulley 10, and a moving pulley 12 suspended around the endless wire 11 are mainly configured.

A plate member 13 having a hanging hole 13a is welded and fixed to an upper end surface 9b of each projecting end portion 9a of the hanging beam 9, and a plurality of holes 14a are horizontally connected to the lower end surface 9c. The plate material 14 thus formed is welded and fixed.
One end of a lifting wire 15 ... Is connected to the hanging hole 13a of the plate member 13 fixed to the upper end surface 9a, as shown by a two-dot chain line in the figure. The other ends of the lifting wires 15 ... Are gathered above the suspension beam 9 so that they can be connected to a hook (not shown) of the lifting machine.

The fixed pulley 10 has the pulley 10 inside a support 10a having a substantially U-shaped side surface that opens downward.
A support shaft 10c (horizontal shaft) that rotatably supports b is installed, and an engaging hook 10e is provided on the upper surface of the top plate portion 10d of the support body 10a. On the other hand, the movable pulley 12 is a support 12 similar to the fixed pulley 10.
a, a pulley 12b, a support shaft 12c (horizontal shaft), and an engaging hook 12e (engaging jig).

The endless wire 11 winds around a lower chord portion of a pulley 12a of a moving pulley 12 which will be described later, and
The length of the movable pulley 12 is set so that the movable pulley 12 can be suspended downward, and the movable pulley 12 is wound around the upper chord portion of each pulley 10a of the adjacent constant pulley 10 among the constant pulleys 10 ...

The fixed pulleys 10 ... Are attached to one of the holes 14a of each plate member 14 of the suspension beam 9 and are attached to the shackle 1.
It is connected to the suspension beam 9 by hooking the engaging hook 10e on the shaft 6. The position of the fixed pulley 10 can be appropriately changed according to the width of the precast frame to be lifted by changing the position where the shackle 16 is attached to the holes 14a.

The endless wire 11 is wound around the upper chords of the pulleys 10a of the adjacent fixed pulleys 10 among the fixed pulleys 10 fixed as described above, and between the adjacent fixed pulleys. In the intermediate portion, the pulley 12a of the moving pulley 12 is wound around the lower chord portion, and in this state, the moving pulley 12 is suspended from the endless wire 11 with its engaging hook 12e facing downward.

When a load is applied to any of the engaging hooks 12e of the movable pulleys 12 ... Suspended on the endless wire 11, the engaging hooks are loaded against the constant pulley 10. The moving pulley under load moves downward, and the other moving pulley whose load is not loaded on the engaging hook moves upward, so that the endless wire 11 does not loosen and is in a tension state in which equal tension is always applied. Has been wound around.

Next, the work of raising the precast formwork having a substantially square cross section by the hanging jig 8 of the precast concrete formwork having the above-mentioned structure will be described. First, a side wall portion 2a of the precast formwork 2 (see FIG. 2) that is temporarily placed on the work floor F (temporary storage place) in a horizontal state and that faces the horizontal direction.
Predetermined suspending metal fittings 17 are provided at one end of the
Is fixed, and the shackle 18 is attached to the circular ring 17a attached to the upper end of each suspension fitting.

Next, the hoisting jig 8 is previously hoisted by a lifting machine, and the shackle 18 is hooked with an engaging hook 12e provided on each moving pulley 12 of the hoisting jig 8. Then, the hanging jig 8 is further lifted, and the load of the precast mold 2 is applied so that the endless wire 11 is in a tension state.
2e is applied equally, and thereafter, as shown in FIG. 2, the precast mold 2 is hoisted with an end portion (not shown) to which the hanging metal fitting 17 is not attached as a fulcrum. At this time, as shown in FIG. 3, a rubber cushioning material 19 is arranged between the work floor F and the end of the precast mold 2 which does not serve as a fulcrum, and the precast mold 2 is erected in an upright state. After making (Fig. 4
(See), and hoist it further upward, and carry it to a predetermined standing position.

In the hoisting jig 8 of precast concrete having the above-mentioned structure, the precast formwork 2 is lifted by a lifting machine (not shown).
The engaging hook 1 of the movable pulley 12 when
Regardless of the engagement position of 2e, the endless wire 11 wound around the fixed pulleys 10 ... And the moving pulleys 12 ... does not slacken and is always in a tensioned state, and the load of the precast mold 2 is always applied to each engagement hook 12e. Are equally loaded, an unbalanced load is applied to the precast formwork 2 to be lifted and the work is performed.

Further, since the cushioning material 19 is disposed between the floor surface F of the work floor and the lower end of the precast formwork 2 which does not serve as a fulcrum, as the precast formwork is lifted, the end serving as the fulcrum is formed. Even when the precast mold 2 makes a pendulum motion when it is separated from the work floor F, contact between the work floor F and the lower end which is not the fulcrum of the precast mold 2 is avoided.

As described above, according to the hanging jig 8 of the precast concrete formwork of the above-mentioned embodiment, the movable pulley 12 is provided at one end of the precast formwork 2 which is temporarily placed in the state of being laid down. By engaging the engaging hook 12e and hoisting upward with the other end of the precast mold 2 as a fulcrum, the precast mold 2 to be hoisted can be erected without applying an unbalanced load. Therefore, the precast formwork 2 temporarily placed in the temporary storage place in a state of being laid down can be safely raised without damage, and the subsequent erection work can be efficiently performed.

Further, since the cushioning material 19 is arranged between the lower end of the precast mold 2 which does not serve as the fulcrum and the working floor F, when the precast mold 2 is erected by the hanging jig 8. Even when the precast mold 2 makes a pendulum motion due to the movement of its center of gravity, it is possible to avoid contact between the lower end of the precast mold 2 and the work floor F and prevent damage.

In the above embodiment, the precast concrete formwork 2 having a rectangular cross section is used with four fixed pulleys 10 and four movable pulleys 12, and a substantially cross-shaped suspension in plan view is used. Although the beam 9 is used, it goes without saying that the number of the fixed pulleys 10, the moving pulleys 12, the shape of the hanging beam 9 and the like can be appropriately changed depending on the shape of the precast concrete formwork to be lifted.

FIG. 5 shows a second embodiment of a hoisting jig for a precast concrete formwork according to the present invention. In the figure, the same parts as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. In the second embodiment, as shown in FIG. 5, instead of the endless wire 11 in the first embodiment, a wire 20 whose both ends 20a are finished in an arc shape is used. 20 a is directly connected to one plate member 14 ′ fixed to the lower end surface 9 c of the hanging beam 9 via a shackle 16, and a fixed pulley 10 is connected to each of the remaining three plate members 14 by a shackle 1.
It is configured to be connected via 6.

Under this structure, as in the first embodiment, the precast mold 2 temporarily placed in the sideways state.
By engaging the engaging hooks 12e provided on each of the movable pulleys 12 with one end of the precast mold 2 and hoisting the precast mold 2 upward with the other end of the precast mold 2 as a fulcrum, the precast mold 2 is lifted. It is possible to stand without imposing an unbalanced load on. Therefore, the precast formwork 2 temporarily placed in the temporary storage place in a state of being laid down can be safely raised without damage, and the subsequent erection work can be efficiently performed.

[0031]

According to the hoisting jig for precast concrete formwork and the method for hoisting precast concrete formwork according to the present invention, the following effects can be obtained. According to the precast concrete formwork suspension jig of claim 1, when a load is applied to any of the engaging jigs of the plurality of moving pulleys, the suspension jig of any one of the fixing pulleys is used. As the moving pulley moves downward, any other moving pulley moves upward, and the wire is in a tension state in which the same tension is always applied without slackening, so that the load applied to the engaging jig is The load is equal regardless of the engaging position of the engaging jig. Therefore, when the precast concrete formwork is lifted to stand up, the precast concrete formwork can be caused without applying an unbalanced load.

According to the method of hoisting the precast concrete formwork of claim 2, the engaging jig attached to the movable pulley is engaged with one end of the precast concrete formwork temporarily placed in a lying state. In this case, the precast concrete form can be raised without applying an unbalanced load to the precast concrete form by lifting the other end with the other end as a fulcrum. Therefore, the precast concrete formwork temporarily placed in the state of being laid down can be safely brought up without damage, and the precast concrete formwork can be efficiently installed.

Further, since the cushioning material is interposed between the lower end portion of the precast concrete formwork which is not the fulcrum and the temporary storage space, when the precast concrete formwork is lifted, the precast concrete formwork Even when a pendulum movement is performed due to the movement of the center of gravity, it is possible to avoid contact between the lower end of the pendulum and the floor surface of the temporary storage space, and prevent damage to the precast concrete.

[Brief description of drawings]

FIG. 1 is a side view of essential parts showing a first embodiment of a hoisting jig for a precast concrete formwork of the present invention.

FIG. 2 is a perspective view showing a situation in which the precast concrete formwork is hoisted using the hanging jig for the precast concrete formwork of the same embodiment.

FIG. 3 is a side view showing a situation where the precast concrete formwork is being hoisted using the precast concrete formwork suspension jig of the embodiment.

FIG. 4 is a perspective view showing a situation in which a precast concrete formwork is hoisted using the precast concrete formwork suspension jig of the embodiment.

FIG. 5 is a side view of essential parts showing a second embodiment of the hanging jig for precast concrete formwork of the present invention.

FIG. 6 is a perspective view of an essential part showing a conventional hanging jig for a precast concrete formwork.

FIG. 7 is a perspective view of a main part showing a situation in which a precast concrete formwork is hoisted using the conventional hoisting jig.

[Explanation of symbols]

 2 Precast concrete formwork 8 Precast concrete formwork suspension metal fittings 9 Suspended beam 10 Fixing pulley 11 Wire 12 Moving pulley 12e Engaging jig 19 Buffer material F Temporary storage

Claims (2)

[Claims] 1. A hoisting jig for a precast concrete formwork used when hoisting a precast concrete formwork, the hoisting beam, a plurality of fixing pulleys fixed to the hoisting beam, and a plurality of these pulleys. A wire wound around the fixing pulley and a plurality of moving pulleys suspended around the wire, and the wire is tensioned when the plurality of moving pulleys are suspended around the wire. The plurality of moving pulleys are arranged so as to be vertically movable relative to the plurality of fixing pulleys, and are engaged with the precast concrete formwork below the moving pulleys. A hoisting jig for precast concrete formwork, which is provided with a fitting jig. 2. A method of hoisting a precast concrete formwork using the hoisting jig for a precast concrete formwork according to claim 1, wherein one of the precast concrete formwork is temporarily laid down in a temporary yard. The engaging jig provided on the movable pulley is engaged with the end portion of the precast concrete formwork so that the wire is tensioned by lifting the suspension beam so that the load is equal to the engaging jig. With loading, and then lifted up with the other end of the precast concrete formwork as a fulcrum to stand up, and between the floor surface of the temporary storage and the part that does not serve as a fulcrum of the other end of the precast concrete formwork. A method of hoisting a precast concrete formwork, characterized in that a cushioning material is interposed therebetween.