JPH0288848A - Formation method for through-hole form of reinforced concrete beam - Google Patents

Abstract

PURPOSE:To assemble a through-hole form simply and speedily, to reduce a construction period and to reduce a cost by inserting bar members, one by one, into circular channels afterward against anchorages previously provided to a beam form. CONSTITUTION:A circular channel member provided with groove insertion inlets 9 on the outside parts of the upper ends of circular channels 8 is anchorages 5, and the anchorages 5 are so fixed to the inside surfaces of beam forms 4 that they are opposed to each other. After that, both ends of a bar member 13 are inserted into the circular channels 8 through the groove insertion inlets 9 to lay the bar member 13 between the anchorages 5, and bar members 13 laid over previously are subsequently inserted into the circular channels to form cylinders 15 by placing a large number of bar members in parallel. According to the constitution, a through-hole form (a sleeve member) of reinforced concrete beam can be easily and speedily assembled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for forming a through-hole formwork for forming a through-hole for piping in a reinforced concrete beam.

[Conventional technology]

To form a through hole (sleeve) 2 for piping in the width direction of a reinforced concrete (RC) beam 1 as shown in FIG.
Before pouring concrete, a hole-forming material (sleeve material) made of a tube or a metal tube is set in the formwork to secure the hole space.

By the way, since the beam part is a structurally important part, there is a large amount of reinforcing bars, and especially around the through hole 2, reinforcement reinforcing bars are also added, so the amount of reinforcing bars is even larger. As a method of arranging such reinforcing bars within the beam formwork, slab 3 (this slab 3
In some cases, it may be on the slab formwork before it is formed. ) and then dropping it into the formwork, but this method requires a dropping jig, requires planning for temporary passageways, etc., and has many constraints, which increases construction costs.

Therefore, generally, beam reinforcing bars are often assembled within the beam form, but in that case, the relationship with the attachment of the sleeve material becomes a problem. The reinforcing bars to be assembled will occupy the entire width of the beam formwork, so if the diameter is relatively large, the sleeve material is set in the formwork during the reinforcement work, and the sleeve material is then placed inside the formwork. The assembly of the beam reinforcing bars will now be completed.

[Problem to be solved by the invention]

However, if sleeve materials are placed in the middle of reinforcing work, it is difficult to determine the timing, which increases the waiting time for the work, and also because of the need for reinforcing steel work and assembly numbers. , the reinforcement accuracy also decreases.

An object of the present invention is to eliminate the disadvantages of the conventional example, and to easily and quickly assemble a formwork (sleeve material) for a large diameter through hole even after the beam reinforcing bars have been completely or mostly assembled within the beam formwork. An object of the present invention is to provide a method for forming a formwork for a through hole in a reinforced concrete beam.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention uses a circular channel material having a cutout insertion opening at the outer part of the upper end of the circular groove as a fixture, and fixes the inner surface of the beam formwork so as to face each other. , insert both ends of the bar member into the circular groove through the notch insertion opening, and span the bar member between the fixtures, and feed the bar members that were spanned first sequentially along the circular groove to create a large number of bar members. The gist is to form a cylindrical body by arranging them in parallel.

(Function) According to the present invention, the bar members are inserted one by one into the circular grooves of the fixture which is first attached to the beam formwork. Insertion can be carried out through the gaps even after the beam reinforcing bars have been assembled within the beam formwork.The bar members inserted one after another and stretched between the fixtures form a cylindrical body, and the bar members are inserted into the beam formwork and stretched between the fixing devices. It becomes the formwork (sleeve material) for the through-hole.

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

Fig. 1 is a vertical side view showing one embodiment of the method for forming a formwork for through holes in reinforced concrete beams according to the present invention, Fig. 2 is a sectional view taken along line A-A of Fig. 1, and Figs. The figure shows each step.

In the figure, 4 indicates a beam formwork, and 14 indicates a slab formwork. As shown in Fig. 3, a fixture 5 is marked out in advance on the inner surface of the standing board member that forms the beam side surface of the beam formwork 4. Install it instead.

As shown in FIG. 6, this fixture 5 is a vertical circular channel material having a circular groove 8 formed by an outer ring 6 and an inner ring 7 with its opening facing horizontally, and the outer part of the upper end of the circular groove 8. An insertion opening 9 was formed by cutting out a part of the outer ring 6. Further, a ring-shaped mounting flange 10 is provided protruding from the deep end of the inner ring 7 in a direction perpendicular to the inner side, and a needle fixing hole 11 is bored in this flange 10.

By nailing the flange 11 to the beam formwork 4 through the nailing hole 11, the fixtures 5 are attached to the inner surface of the beam formwork 4 such that two of them face each other. Note that the fixture 5 may be attached before or after the beam form 4 is assembled.

Next, as shown in FIG. 4, beam reinforcing bars 12 are placed inside the beam formwork 4.
Assemble. In the figure, 12a is the main beam reinforcement of the beam reinforcing bars 12, 12b is the stirrup reinforcement, and 12c is the reinforcing reinforcement around the through hole.

After the beam reinforcing bars 12 are completely or mostly assembled in this way, a bar member 13 made of light metal such as lightweight channel steel or C-channel material is inserted through the gap between the beam reinforcing bars 12 as shown in FIG. Insert both ends into the circular groove 8 through the notch insertion opening 9 of the fixture 5.

This work can be performed from the top of the slab formwork 14 through the upper end opening of the beam formwork 4, and the bar member 13, whose both ends are in the circular groove 8, should have its opening face inside (toward the mounting flange of the fixture 5). It is horizontally spanned between the fixtures 5, 5.

A large number of the bar members 13 are inserted between the fixtures 55 in the same manner, and the bar members 13 that were first inserted into the circular groove 8 are sequentially fed into the back along the groove 8 from the insertion opening 9 ( (See arrow in Figure 2).

As a result, the bar members 13 are arranged in parallel along the circular groove 8 and form a cylindrical body 15.

If concrete is poured into the beam formwork 4 in this way, this cylindrical body 15 acts as a sleeve material, and when the concrete hardening formwork 4 is demolded together with the fixture 5, it is shown in FIG. A through hole 2 is formed in the cylindrical body 15 as shown in FIG. Note that the bar member 13 forming the cylindrical body 15 can be removed in pieces and reused.

〔Effect of the invention〕

As described above, the method for forming a formwork for a through-hole in a reinforced concrete beam of the present invention allows the formation of a formwork for a through-hole with a large diameter easily and quickly even after the beam reinforcing bars have been completely or mostly assembled within the beam formwork. It can be assembled in a number of ways, and can bring about significant streamlining such as shortening the construction period and cost in sleeve construction.

In addition, there is no risk of disturbing the reinforcement arrangement, etc., and it also leads to improved precision of beam reinforcing bars.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional side view showing one embodiment of the method for forming a formwork for through-holes in reinforced concrete beams according to the present invention, FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1, and FIGS. 3 to 5 6 is a side view showing each step of the present invention, FIG. 6 is a perspective view of a fixture, FIG. 7 is a perspective view after removing the beam formwork, and FIG. 8 is an explanatory view of a beam through hole. 1... Reinforced concrete beam 2... Through hole 3... Slab 4... Beam formwork 6... Outer ring 8... Circular groove 10... Mounting flange 12... Beam reinforcing bar 12b. ... Stirrup bar 12c... Reinforcement bar 14... Slab formwork 5... Fixture 7... Inner ring 9... Insertion port 11... Needle hole 12a... Beam main bar 13 ... Bar member 15 ... Cylindrical body

Claims (1)

[Claims] A circular channel material having a notch insertion hole at the outer part of the upper end of the circular groove is installed as a fixture on the inner surface of the beam formwork so as to face each other, and both ends of the bar member are inserted into the circular groove through the notch insertion hole. For through-holes in reinforced concrete beams, characterized in that the bar member is inserted and spanned between fixtures, and the previously spanned bar members are sequentially fed along a circular groove and arranged in large numbers in parallel to form a cylindrical body. How to form formwork.