JPS6049724B2 - Shoring of structures in construction work - Google Patents

Description

[Detailed description of the invention] The present invention relates to shoring of structures in construction work.

Conventionally, bridge girders are structures that are lowered during construction work.

That is, when a bridge girder is erected on a pier, it is hoisted up by a crane and temporarily supported on a support called a bend, and after being accurately positioned on the support, it is lowered and placed and fixed on the pier. It's summery.

However, the work of hoisting a bridge girder with the above-mentioned crane, that is, the finishing work, is more difficult as the bridge girder is larger and the piers are taller, and it is accompanied by many dangers.

In addition, the lowering work of the bridge girder is carried out by stacking a large number of steel members on the shoring and then installing a large number of hydraulic jacks on top of the steel members to support the bridge girder, using the following work procedure.

That is, first, remove the steel material that has moved away from the installation position of the hydraulic jack, install a new hydraulic jack in the lower part where the steel material was removed, shorten the hydraulic jack that was supporting the bridge girder, and then The bridge girder is gradually lowered by repeating a series of steps in which the bridge girder is supported by the hydraulic jacks installed from above, the retracted hydraulic jack is removed, the steel material at the installation location is removed, and the same jack is reinstalled there. I'm letting you do it.

However, when the above method is adopted, it takes time and effort to attach and detach the hydraulic jack and remove the steel material, resulting in extremely poor workability and safety problems.

On the other hand, once the bridge girder has been erected, the shoring must be removed, but since there is only a small gap between the shoring and the erected bridge girder, the shoring cannot be removed mechanically using a crane or other means. Since the shoring could not be removed, the shoring had to be manually disassembled and removed, making the work extremely inefficient. An object of the present invention is to expand and contract the shoring itself so that finishing lowering of structures such as bridge girders and shoring removal work can be performed quickly and safely.

i An example of the implementation of the present invention will be described with reference to the drawings. As shown in Figures 1 to 3, the shoring A has an underframe a and four screw rods 1, and is configured to be extendable and retractable.

The underframe a has four hollow pillars 2, and these pillars 2
are connected by side frames 3 and 4 to form a box shape with a rectangular plane.

The support column 2 is made of a vibrating material with a circular cross section, and its upper end is closed to prevent rainwater from entering the inside.

On the other hand, the screw rod 1 is formed by cutting a thread along the entire length of the outer periphery of a relatively thick vibrator material, stands up at the lower end via a pedestal 5, and the upper part is slidably inserted into each of the pillars 2. There is.

The movement of the screw rod 1 within the column 2 is guided by a guide 6 at the lower end of the column 2, as shown in FIG.

The guide 6 is made of a cylindrical body that fits around the outer periphery of the screw rod 1, and has a flange 7 at the upper end of the screw rod 1 at its upper end.
It also functions as a stopper that locks the lower end and prevents the screw head 1 from coming off from the support 2.

Reference numeral 8 denotes a hydraulic jack provided on a protrusion from the support column 2 in each screw rod 1;
and are each connected to one hydraulic pump (not shown) for synchronized operation. As shown in FIG. 4, the hydraulic jack 8 is of a so-called center hole type that is fitted onto the outer periphery of the screw rod 1 so as to be slidable up and down, and a hollow operating rod 8b protrudes from the lower end of the casing 8a.

The hydraulic jack 8 is connected to the lower end of the support column 2 via a highly rigid connecting member 9 called a ram tie air at its upper end.

The upper and lower flange portions 9a and 9b of the connecting member 9 are bolted to the column 2 and the casing 8a of the hydraulic jack 8, respectively.

The distance between the flange portions 9a and 9b is set to be approximately equal to the expansion/contraction stroke of the hydraulic jack 8.

A stopper 10 is located above the hydraulic jack 8 and locks the lower four ends of the support column 2. The stopper 10 is screwed onto the screw rod 1 and abuts against the lower surface of the upper flange portion 9a of the connecting member 9.

Reference numeral 11 denotes a stopper located below the hydraulic jack 8 for locking the jack 8, which is screwed onto the screw rod 1 and abuts against the lower end of the operating rod 8b of the hydraulic jack 8. 1
Reference numeral 2 denotes a handle provided on the stopper 11 to facilitate rotational operation thereof.

In the figure, reference numerals 13 and 14 are side frames provided to ensure the rigidity of the lower half of the shoring A, and are detachably attached to the lower part of each screw rod 1.

9 The above-mentioned shoring A supports structures such as the bridge girder B and lifts and lowers them, but there are three ways to use it.

The first case is when shoring A is used alone, and in this case, shoring A directly supports 7 the bridge girder B on the upper end of the underframe a.

The second case is when one or more supports A are stacked together with conventional supports called bends and connected to each other. In this case, support A is used at either the top, middle or bottom. The bridge girder B may be installed directly or indirectly.

The third case is when a plurality of supports A, for example, two supports A, are stacked and connected to each other as in this embodiment. In this case, each support A expands and contracts individually, so the bridge girder B can be raised and lowered to the greatest extent possible. .

It goes without saying that in the above three usage modes, the shoring A can be used upside down.

When the bridge girder B is lifted up, each of the supports A is extended simultaneously or separately, but since the operations are the same, only the operation of one support A will be described. First, as shown in FIG. 5, the hydraulic jack 8 is contracted and locked by the lower stopper 11, and the jack 8 is extended with the upper stopper 10 locking the lower end of the column 2.

As a result, the underframe a moves upward until the upper stopper 10 comes into contact with the upper surface of the lower flange portion 9b of the connecting member 9, as shown in FIG. 6, and the bridge girder B is lifted up.

After the underframe a moves up by a predetermined amount as described above, the seventh
As shown in the figure, the upper stopper 10 is rotated and moved upward until it abuts the lower surface of the upper flange portion 9a of the connecting member 9, and the lower end of the support column 2 is engaged with the stopper 10, and the underframe a is prevent descent.

Next, the hydraulic jack 8 is retracted and the lower stopper 11 is rotated to move it upward until it abuts the lower end of the operating rod 8b of the hydraulic jack 8, and the fifth
Set the state to be the same as shown in the figure.

By repeating the above operations and operations, the underframe a is intermittently moved upward until the flange 7 at the upper end of the screw rod 1 comes into contact with the upper end of the guide 6, and is gradually pushed onto the bridge girder B to a predetermined height position. let it go up

On the other hand, the work of lowering the bridge girder B is performed by contracting the shoring A. That is, from the state where the upper stopper 10 locks the lower end of the column 2 and the hydraulic jack 8 is contracted as shown in FIG. 8, the lower stopper 11 is rotated to lower the hydraulic jack 8 by the stroke thereof.

Then, as shown in FIG. 9, the hydraulic jack 8 is extended until it comes into contact with its operating rod 8b and the stopper 11, and after the jack 8 supports the underframe a, the upper stopper 10 is rotated. It is lowered until it abuts the upper surface of the lower flange portion 9b of the connecting member 9. Next, by retracting the hydraulic jack 8, the underframe a is lowered until the upper stopper 10 comes into contact with the lower surface of the upper flange portion 9a of the connecting member 9, as shown in FIG. 10, and the bridge girder B is lowered.

After the underframe a has been lowered by a predetermined amount as described above, the lower stopper 11 is lowered again and the same operations and operations as described above are repeated. By lowering the underframe a intermittently in the manner described above, it is lowered in stages to the upper surface of the bridge girder B or pier C.

The contraction operation of the shoring A is performed until the lower stopper 11 comes into contact with the pedestal 5 at the lower end of the screw rod 1 by removing the side frames 13 and 14 at the lower end of the screw rod 1.

The contraction movement amount and the expansion movement amount of the shoring A are 27n in this example.

On the other hand, after the bridge girder B has been lowered onto the pier C, the shoring A is further contracted and separated downward from the bridge girder B, and is removed by a crane or the like (not shown) in order from the upper side.

In addition, the above-mentioned shoring A has a concrete slab (
When constructing a concrete slab (floor slab), it can also be used as a means to support a form (not shown) for pouring concrete. By doing so, it can be moved far away from the concrete slab and easily removed using a crane or the like.

The present invention achieves the following effects with the above configuration.

By supporting one structure with shoring and expanding and contracting the shoring itself, the structure can be raised and lowered stably and quickly. After the two structures are installed, the shoring is contracted and separated downward from the structure, creating a large gap between the shoring and the structure, and the shoring can be quickly removed mechanically using a crane or the like.

The shoring is intermittently expanded and contracted by moving the stoppers that lock the supports of the three frames and the stoppers that lock the hydraulic jacks by a predetermined amount alternately along the screw rod while extending and contracting the hydraulic jacks. The lifting and lowering of structures is carried out in stages, resulting in superior work safety.

[Brief explanation of the drawing]

Figure 1 is a front view showing how the shoring structure of the present invention is used;
The figure is an enlarged front view of the shoring, Fig. 3 is the same side view, Fig. 4 is an enlarged partially cutaway front view showing one support and screw rod, and Figs. 5 to 10 are the shoring. It is an explanatory diagram of the expansion and contraction operation. In addition, in the figure, A...... shoring, a...... underframe, 1...7 screw rod, 2...... pillar,
8... Hydraulic jack, 10, 11... Stopper, B... Bridge girder (structure), C...
・Pier.

Claims (1)

[Claims] 1.Equipped with an underframe having a plurality of hollow supports, and a screw rod that is slidably inserted into each support of the underframe and projects from the support, the protrusion of the screw rod from the support is the same as the screw rod. A hydraulic jack that can be moved along the rod is connected to the support, and a stopper is provided on one side of the jack to engage the screw rod and lock the support, and the same is provided on the other side. Shoring for structures used in construction work with a stopper that screws onto a screw rod and locks a hydraulic jack.