JPS6234903B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for assembling reinforcing bars in construction or civil engineering reinforcing work.

Reinforcing bars are the backbone of reinforced concrete structures, and are required to be appropriately placed at predetermined positions.

The work of arranging and assembling such reinforcing bars is a troublesome work of fixing individual reinforcing bars one by one with binding wires, and is extremely time-consuming and labor-intensive.

In addition, gas pressure welding is usually used for joints between reinforcing bars, but this requires the advanced skills of qualified personnel who have passed a skill test.

Furthermore, these assembling and press-welding operations often involve work at heights, and are extremely dangerous operations that are prone to falling accidents.

The purpose of the present invention is to fully take into consideration the special circumstances of reinforcing steel assembly work in construction work, and to firstly improve work safety, secondly to achieve significant cost reduction, and thirdly to provide sufficient strength. Our goal is to provide a reliable reinforcing steel assembly method.

However, according to the present invention, the purpose of the lever is to assemble required parts of columns, beams, walls, and slabs in construction or civil engineering work on the ground by electric welding, and to lift each assembled member using clay. The mutual joining of each member is achieved by electrically welding the large diameter portions formed at the ends of the reinforcing bars.

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

First, regarding the reinforcing bars used in the present invention, for relatively small-diameter reinforcing bars such as SD10, SD13, and SD16, thick diameter portions 2 are formed at appropriate locations on the reinforcing bar 1 as shown in Fig. 1. use. This large diameter portion 2 preferably has a rectangular cross section.

The reinforcing bar 1 is manufactured by first extruding a square material with a rectangular cross section by passing it between fixed rotating rolls of a strip mill, and then extruding the square material by passing it between fixed rotating rolls of a strip mill. The material may be passed between two rotating rolls made of rolled rolls, and the large diameter portion 2 may be left open and the rest may be squeezed to form a circular cross section.
Note that the pitch of the large diameter portion 2 is preferably about 1500 mm.

Such small-diameter reinforcing bars 1 such as SD10, SD13, and SD16 are usually used as reinforcement for walls and slabs.

Fig. 2 is a perspective view showing the case where slab reinforcement is assembled into the ground using the above-mentioned reinforcing bars 1, and the reinforcing bars 1 assembled in a lattice shape have their intersections in contact with the large diameter portions 2 as shown in Fig. 3. Since this often happens, this part is spot welded to fix it. Fig. 3a shows a case where the large diameter parts 2 are located at the intersection, and Fig. 3b shows a case where the large diameter parts 2 come on one side and the normal side of the reinforcing bar 1 on the other. The plane of portion 2 can provide a sufficient area for spot welding.

Note that there are intersections where there is no thick diameter 2 at all, but
This part can be fixed with thick binding wire for civil engineering.

Figure 4 is a perspective view of wall reinforcements assembled into the ground. When multiple lattice bodies 3 of reinforcing bars 1 are arranged in parallel in this way, each lattice body 3 is connected to a square-shaped connecting reinforcing bar 4. Link. FIG. 5 is an enlarged view showing the details of the connecting part, and the end of the connecting reinforcing bar 4 is fixed to the side surface of the reinforcing bar 1 by electric welding.

In addition, when assembling wall reinforcements in this way, it is sufficient to assemble the lattice body 3 horizontally and then vertically when lifting it, and high scaffolding is not required at all during the assembly work. In the reinforcement arrangement of a slab, when a plurality of lattice bodies 3 are lined up, they are similarly connected by reinforcing bars 4.

The slab reinforcements and wall reinforcements constructed as described above are welded at appropriate locations via the large diameter portions 2, and
Since the lattice bodies 3 are welded and connected to each other by reinforcing bars 4, the lattice bodies 3 are strong and can sufficiently withstand the lifting load of a crane or the like even if other parts are fixed with binding wires or wires.

Next, the large diameter reinforcing bars of SD25, SD30, and SD35 or larger used in the present invention will be described.

As shown in FIG. 5, such large-diameter reinforcing bars 5 are formed with a large-diameter portion 6 having a tapered end surface 6a at the end thereof. This tapered end surface 6a
is formed so that it has an area that is at least 2.5 times the vertical cross-sectional area of the reinforcing bar 5 other than the large diameter portion 6, and can exhibit strength that meets JIS standards. As with the reinforcing bar 1, the reinforcing bar 5 is produced by first passing a square material with a rectangular or semicircular cross section between fixed rotating rolls of a strip mill, and then passing it between a vertically movable roll and a fixed roll. It is passed through, leaving a portion that will become the large diameter portion 6, and the rest is squeezed to form a circular cross section.

The large diameter portion 6 of the product obtained in this way was
As shown in the figure, two reinforcing bars 5 can be obtained by cutting at an angle of about 45° or less using a cutting machine such as a shearing machine. Note that if a V-cut groove 7 is provided along the cutting line when cutting, a welding cut portion 8 can be formed at the periphery of the tapered end surface 6a at the same time.

This large-diameter reinforcing bar 5 is used as the main bar for columns and beams.

To explain the case of assembling columns or beams using the reinforcing bars 5, as shown in Fig. 8, the reinforcing bars 5 are inserted from the end into hoop bars 10 that are arranged in parallel on the ground in advance using a jig 9. Further, as shown in FIG. 9, the four sides of the reinforcing bars 5 disposed at the four corners of the hoop reinforcing bars 10 are connected by square-shaped connecting reinforcing bars 11. The reinforcing bars 11 are crossed at the center, and the ends a,
Electrically weld a' and this intersection b (spot welding)
It is fixed with. Further, the hoop reinforcement 10 and the reinforcing bar 5 serving as the main reinforcement may be fixed using thick binding wire for civil engineering.

Both columns and beams are assembled using the method described above, and in the case of columns in particular, they can be assembled horizontally on the ground and then lifted vertically; high scaffolding is not required for assembly work.

The reinforcing bars for walls, slab columns, beams, etc. that have been assembled on the ground in this way are lifted up by a crane and erected at predetermined positions at high places, as shown in FIG. 1st
In Figure 0, a is the state where the slab reinforcement and wall reinforcement are lifted.
The construction can be streamlined by prefabricating the columns and beam reinforcements in a cross or square shape as shown in b, with the column reinforcements and wall reinforcements lifted.

When it is necessary to join members such as columns and beams to each other, as shown in FIG. Electric welding may be performed using part 8. Since this end face 6a has an area more than 2.5 times the normal cross section, a sufficiently strong joint can be obtained without the need for troublesome work such as pressure welding.

As described above, the reinforcing bar assembly method of the present invention is
Reinforcing steel members for columns, beams, walls, and slabs are assembled on the ground by electrical welding at the required locations, and each assembled member is lifted by a crane. Each member is joined to the larger diameter portion formed at the end of the reinforcing steel. Since we decided to electrically weld the parts together, all we had to do was assemble all the parts on the ground, make them into prefabricated pieces, lift them up with a crane, and build them.
Since the proportion of work at heights can be reduced, there is no need for high scaffolding for assembling reinforcing bars, and manpower and work time can be saved, leading to significant cost reductions.

In addition, the reduction in the amount of work required at heights in particular prevents accidents such as falls, thereby significantly increasing safety.

Furthermore, each prefabricated member assembled on the ground is strong and fixed at required points by welding, and can withstand impact when lifted by a crane.

Electric welding can also be used to join parts together at high places, and by doing everything with electric welding, it is possible to streamline construction by omitting pressure welding work that requires highly skilled technicians. It is.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a small diameter reinforcing bar used in the present invention;
Fig. 2 is a perspective view of the slab reinforcement, Fig. 3 is a sectional view showing the same joint as above, Fig. 4 is a perspective view of the wall reinforcement, Fig. 5 is a side view of the main part of Fig. 4, and Fig. 6 is A partial perspective view of large-diameter reinforcing bars used in the present invention, FIG. 7 is a perspective view showing the manufacturing process of the reinforcing bars in FIG. 6, and FIG. 8 is a perspective view showing the foundation assembly of columns and beams in an embodiment of the present invention. , FIG. 9 is a perspective view of assembled columns and beam reinforcements, FIG. 10 is a perspective view showing the next step, and FIG. 11 is a side view showing the next step. 1... Rebar, 2... Large diameter part, 3... Lattice body,
4... Connecting reinforcing bar, 5... Large diameter reinforcing bar, 6... Large diameter reinforcing bar portion, 6a... Tapered end surface, 7... V cut groove, 8... Cut portion, 9... Jig, 11...
Rebar for connection.

Claims (1)

[Claims] 1. Reinforcing steel members for columns, beams, walls, and slabs in construction or civil engineering work are assembled on the ground by electrical welding at the required locations, and each assembled member is lifted by a crane, and each member is joined to each other at the ends of the reinforcing bars. A large-diameter portion that has a tapered end surface obtained by cutting a rectangular or semicircular large-diameter portion formed in a section at an angle of approximately 45° or less, and a cut portion for welding is provided on the periphery of the tapered end surface. abutting the tapered end surfaces against each other;
A reinforcing bar assembly method characterized by electric welding using cut parts.