JP3167624B2 - Hollow slab method, reinforcing bar arrangement unit and method for manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a hollow slab method used in a construction site.

[0002]

2. Description of the Related Art Needless to say, the hollow slab method is a method of constructing a floor surface for each story of a reinforced concrete building, in which reinforcing bars are knitted on the upper surface of a hollow slab formwork in a vertical and horizontal crisscross shape. Spread the lower end streaks, arrange a number of hollow tubes such as lightweight spiral steel pipes positioned in parallel on them and fix them in place.Furthermore, knit the reinforcing bars in a vertical and horizontal cross-like shape to form the upper end streaks. In this method, the upper and lower muscles are tied together by longitudinal muscles and firmly connected, and concrete slurry is poured to form a floor surface with a hollow portion.

It is true that the hollow slab method uses a large number of hollow pipes to reduce the weight compared with the conventional method in which the entire floor is formed of a concrete frame reinforced with steel bars, and imposes a load on the steel frame. Since the weight is reduced, there is no doubt that there is an advantage in terms of strength calculation, and eventually, an advantage associated with a reduction in construction costs. However, looking at the man-hours required for the progress of the construction, the worker knits reinforcing bars one by one on the upper surface of the hollow slab form to form a wide bottom line, forming a wide bottom line. Arrange the hollow tube and fix it to the formwork so that it does not rise when casting concrete.Furthermore, stretch the vertical streaks on both sides of the hollow tube, and knit another wide vertical streak-like top streaks on top of each other. It has to go through a very cumbersome and proficient manual task of coupling to

[0004] Because of the nature of the work environment such as a construction site, such rebar arrangement work is inevitably forced to be carried out in high places and in narrow places. However, as long as the premise is that manual work is mainly performed in the on-site arrangement work, it was difficult to find a means to respond to this voice.

[0005]

SUMMARY OF THE INVENTION The applicant has long worked to solve this problem and has presented many inventions and inventions with the aim of eliminating difficult tasks. For example, a “hollow slab support metal fitting” that projects from a hollow slab form to support the pipe in order to fix the hollow slab pipe at a predetermined position in the hollow (Japanese Utility Model Application Laid-Open No. HEI 4-104).
Japanese Patent Application Laid-Open No. 7-164024) and a similar statement, "Fixing a hollow tube to a mold in a hollow slab method".
However, these prior arts are limited to local improvements that are effective only for the simplification of a single process in the entire hollow slab method, and are drastically improved in the complicated and inefficient work as a whole. It did not lead to a basic effect.

In the prior art disclosed in Japanese Patent Application Laid-Open No. Hei 7-305444, the applicant has proposed a new construction method which aims at rationalizing the entire hollow slab construction method and saving labor. The lower muscle unit 102 is formed by a plurality of lower muscles 3a and auxiliary muscles 101 as shown in FIG. 4A, and the upper muscle unit is formed by a plurality of upper muscles 2a and auxiliary muscles 103 as shown in FIG. 104, and a plurality of hollow tubes 5a and a hollow tube unit 107 unitized from main bars 105 and 106, which are arranged in parallel at a distance from each other as shown in FIG. It is manufactured separately, and the lower end muscle unit 10 is placed on the slab formwork at the site.
2, and the hollow tube unit 107 is placed thereon,
The gist is a hollow slab construction method in which the upper end muscle unit 104 is arranged thereon and these are connected to each other.

Certainly, according to this construction method, at least at a construction site, a large number of reinforcing bars are combined with each other on a slab formwork to form a mesh, and the position is determined by a hollow portion above the reinforcing bar to form a hollow. The extremely inefficient and cumbersome work of fixing the pipe, connecting the vertical streaks to the space including the periphery of the hollow pipe, and connecting it to the upper braided mesh that covers the upper surface is considerably reduced. it is obvious. At that point, a certain evaluation can be made as a rationalization of the reinforcing work, but it is indispensable to work to connect the lower end unit and the hollow tube unit, and the hollow tube unit and the upper end unit to each other. This work itself is extremely complicated, and the work of connecting wires and other places in a place where movement is difficult with narrow arrangements is a work that takes more time and effort than you think,
It is hard to say that the task has been completely solved.

In order to completely solve the above-mentioned problems, the present invention provides a unit in which a hollow pipe and a reinforcing bar are integrally incorporated, and a unitary structure is formed by simply arranging the units and connecting the units and placing concrete. The purpose of the present invention is to provide the highest productivity in the hollow slab method by minimizing on-site rebar arrangement work and to provide the structure of the rebar unit itself that enables the method, and to provide a method of manufacturing the same. I do.

[0009]

In the hollow slab construction method according to the present invention, a reinforcing unit used for fixing and arranging a hollow tube in a hollow slab method is formed by bending a single reinforcing bar into a rectangular shape and winding the reinforcing bar in the axial direction. Upper force bar 12, lower force bar 13, which crosses obliquely while alternately inverting the phase up and down, and vertical force bar 11 connecting the upper and lower sides
And a plurality of upper muscles 2 that are fixed to the upper muscle 12 by being laid on the upper muscle 12 at intervals at which a plurality of hollow tubes are arranged in the axial direction of the hollow tube. A plurality of lower streaks 3 that are laid horizontally and fixed at intervals at which a plurality of hollow tubes are arranged in the axial direction of the hollow tube to the force bars 13, and a longitudinal direction that connects and fixes the upper streaks 2 and the lower streaks 3. A hollow tube 5 is inserted and fixed in a section formed almost uniformly by the streaks 4 except for the sections sa and sb at both ends, and the sa and sb are U-shaped joints that project the distribution muscle 1 in a U-shape. Is characterized in that it has a lateral width and a length that can be loaded on the carrier of the transport vehicle.

[0010] As a method of manufacturing the reinforcing bar unit, a procedure of bending a single reinforcing bar having a specified diameter to form a rectangle having a required size, and further forming a rectangle of the same shape with a phase shift, is mechanically performed. Repeatedly forming a large number of continuous rectangular aggregates, stretching the aggregates in a direction perpendicular to the rectangular surface to be formed, and obliquely obliquely inverting the phase vertically in the stretching direction while obliquely moving. 12, the lower force bar 13 and the vertical force bar 11 connecting the upper and lower sides form the force bar 1;
An upper muscle 2 extending in the direction of the hollow tube and an lower muscle 3 extending in the direction of the hollow tube on the lower surface of the lower force muscle 13 are arranged on the upper surface of the upper force bar 12 and fixed. The upper end muscle 2 and the lower end muscle 3
The hollow tube 5 is inserted and fixed except for the sections sa and sb at both ends into a section formed almost uniformly by the vertical streak 4 which is connected and fixed, and the sa and sb stretch the distribution muscle 1 in a U shape. It is characterized by mass-producing a procedure up to a structure for forming a U-shaped joint to be put out in a factory.

The hollow slab construction method using this reinforcing bar unit includes a reinforcing bar 1 which is bent and wound in a rectangular shape, and alternately inverts the phase up and down and skews. A plurality of upper muscles 2 are fixed to the upper force-supplying muscles 12 by arranging a plurality of hollow tubes in the axial direction of the hollow tube at intervals and a lower force-supplying muscle 13 of the force-supplying muscles 1 A plurality of lower streaks 3 which are laid and fixed laterally at intervals where a plurality of hollow tubes are arranged in the axial direction of the empty tube;
A hollow tube is installed and fixed in a section formed almost uniformly by the vertical streak 4 connecting and fixing the upper end streak 2 and the lower end streak 3, and the hollow tube is connected to the ends sa and sb of the section. The upper and lower muscles are not inserted, and the reinforcing bars 1 are extended in a U-shape so that the U-shaped reinforcing joint which overlaps the aa portion and the sb portion of the adjacent unit is connected to the construction site by the vehicle. , And the necessary number of reinforcing bar sets 10A, 10B...
By overlapping the sb, the target floor is integrally formed by pouring the concrete slurry without connecting the units by the function of the joint portion 6.

That is, the reinforcing bar set of the present invention is
The upper frame 2 has a plurality of divisional frame bodies fixed to the upper surface and the lower surface 3 has a lower end line 3 laid horizontally, and the hollow pipe 5 is fixed in the divisional frame. Neither the work of assembling the reinforcing bars on the site to form a mesh nor the work of fixing the hollow tube between the upper and lower meshes at all is necessary. Since it is merely an operation of arranging the reinforcing bar set loaded on the transport vehicle on the hollow slab formwork and preventing floating during concrete casting, it goes without saying that the man-hour is drastically reduced as compared with the conventional case. In addition, the production of the rebar arrangement set to be conveyed is mass-produced continuously in a factory in a mass production system. The work of bending the rebar regularly to the prescribed dimensions is mechanically automated, and the connection to the upper and lower rebars and the fixing of the arrangement of the longitudinal rebars 4 are completed in a short time using an automatic welding machine. In this case, labor savings can be reduced by orders of magnitude as compared with man-hours individually assembled. The advantage of quality controlled factory production is
It is possible to respond to the suspicion that the collapse of the reinforced concrete structure during the earthquake may be due to poor construction of the reinforcing bars by supplying high quality products.

Further, the feature of the on-site hollow slab construction method using the reinforcing bar set is that the connection between the sets arranged adjacent to each other can be omitted, and the concrete slurry can be immediately poured just by arranging. The point is that the epoch-making simplification of the insertion is realized. This is provided by the structural features of the bar arrangement set. That is, although FIG. 3 is a plan view showing the vicinity of the boundary, the hollow portions s defined by the vertical streaks in the adjacent bar arrangement sets 10A and 10B are shown.
a, sb... each contain a hollow tube, but only a U-shaped reinforcing joint protruding in a U-shape is formed only at both ends sa and sb. When viewed from above, the joints look like saw blades are fitted together, and both ends overlap at this point, and the phases are shifted so that the convexes and convexes mesh with each other. Protrude to the other side,
By filling the meshed reinforcing bars with the concrete slurry, a rigid reinforced concrete joint portion 6 capable of transmitting stress without connecting the reinforcing bars is formed. That is, the synergistic effect of the rationalization of the rebar forming and the simplification of the on-site construction is achieved, thereby solving the problem aimed at by the present invention.

[0014]

FIG. 1 is a perspective view showing an embodiment of the present invention. Except for the rectangle starting first, the upper force bar 12 and the lower force bar 13 connected by the vertical force bar 11 form a continuous force bar 1 while maintaining a predetermined rectangle.
A plurality of upper muscles 2 are fixed in parallel on the upper surface of the distributing muscle 1 according to the interval of the hollow tubes, and a plurality of lower muscles 3 are fixed in parallel on the lower surface in accordance with the interval of the hollow tubes. I do. The upper end muscles 2 and the lower end muscles 3 are arranged at positions vertically coincident with each other with the distribution muscles interposed therebetween, and are joined by the vertical streaks 4 to form a plurality of substantially equally spaced sections. s
The hollow tube 5 is inserted and fixed in the compartments SA, SB, ‥‥ except for a and sb. The total length and width of the bar arrangement set 10 are limited to a range in which loading on a large truck is permitted, and the required number of sets are conveyed collectively from a factory, a distribution center, or the like to the site of the bar arrangement work.

The major feature of the method of manufacturing the reinforcing bar set 10 is that it is mass-produced mechanically in a factory. The manufacturing method starts by bending one rebar. The bending method itself does not need to be limited, and may be performed by any known technique. For example, one rebar (usually wound and wound in a coil shape) is bent into a rectangular shape with a mandrel as a core and pressed and bent with a slide punch, then the phase is shifted and the mandrel is similarly wound. It is pressed and bent around and wound into a rectangular shape having the same shape to form a large number of continuously adjacent rectangular aggregates. It is sufficient for other forming methods to obtain the desired rectangular aggregate as shown in FIG.
Needless to say, this molding is all performed mechanically, and the required rectangular cross-sectional area can be arbitrarily selected by changing the size of the mandrel around which the rebar is wound.

When a rectangular aggregate as shown in FIG. 2 is horizontally stretched in a continuous direction (a surface orthogonal to the rectangular surface), the upper side and the lower side are inverted in phase while maintaining the rectangle, and become continuous.
A continuum of the vertical force bars 11, the upper force bars 12, and the lower force bars 13 forming the force bars 1 is formed. The upper muscle 2 is arranged on the upper surface of the upper muscle 11, and the lower muscle 3 is arranged on the lower surface of the lower muscle 13 in a stretched direction. The bars 3 are welded and joined by the vertical bars 4 to complete the framework of the bar arrangement unit 10. Furthermore, if the hollow tube is inserted and fixed, the rebar arrangement unit is completed, but all work is advanced automatically as much as possible using the equipment in the factory, bending machine, positioning device, automatic welding machine, The work of arranging the reinforcement in the above is only the work of fixing the hollow tube unit to the hollow slab formwork to prevent the floating during concrete casting, and can be reduced to at least about 30% of the conventional work.

FIG. 3 shows a case where the reinforcing members 10A, 10B,...
The joints 6 of the two units are uncoupled by the sections sa and sb at both ends projecting from each other.
It forms a U-shaped joint. Demonstrates the reliability of the connectionless method between the reinforcing bar sets, which is another great feature of the present invention. The details are based on the “Basic Research on Development of Hollow Slab Unitization Method” by Michisuga, Sato and Ikeda, published in March 1996 by the Architectural Institute of Japan. Since the stress transmission capacity of the distributing muscles naturally depends on the difference in the connection method of the distributing muscles, it was determined that it was necessary to experimentally verify the transmitting ability when adopting a new joint method. As a new joint method, the hollow part (hollow pipe) at the end of the unit is deleted, so that a U-shaped reinforcing joint is adopted in the concrete of the slab. For comparison with joints, test specimens for pure bending and those subjected to bending shear were manufactured. For pure bending specimens, two types of force methods, monotonic force and positive side incremental repetitive force, were adopted. did.

Although some interesting data were obtained in the above experiment, for example, comparing the maximum proof stress, the results of the repetition test of the pure bending test and the result of the bending shear test showed that
Although the use of the K-shaped joint only slightly increases compared to the case of the conventional lap joint, the maximum yield strength is increased by about 20% in the pure bending monotonic force test. In addition, in the case of the lap joint in the bending shear test, a rapid decrease in proof stress occurs immediately after reaching the maximum proof stress, and it is considered that the cause is due to slippage of the reinforcing steel of the lap joint.

Summarizing the experimental results, when the distribution bars of the hollow slab are in a stress state below the yield strength, the stress of the distribution bars does not increase even if the joint method using U-shaped reinforcement is adopted in the concrete of the slab. Since it can transmit sufficiently, it can withstand practical use without lowering of bending strength,
In the case of the 0d lap joint, a clear sliding of the reinforcing bar is observed before and after the yield strength, and the bending strength of the entire slab is sharply reduced. On the other hand, the degree of the sliding is very small in the 20d U-shaped joint. Since the decrease in bending strength is also small, it is concluded that there is a high possibility that it will be a more reasonable joint construction method, and the superiority of the non-bonded reinforcing joint method only by juxtaposition of the reinforcing bar set of the present invention is experimentally determined. Suggests. It should be noted that the U-shaped joint has only a symbolic U-shape, and can be selected from various shapes such as a U-shape, a semicircle, and an arc.

[0020]

As described above, according to the present invention, it has conventionally been necessary to perform a reinforcing work at a construction site, and the complicated and skillful work has been a major bottleneck for reducing the construction cost and the construction period. In this way, it was possible to bring in a large number of mechanically and automatically mass-produced rebar sets at the factory and simply line them up, resulting in an epoch-making labor-saving and cost-saving effect. In this case, since the units are merely arranged, an experiment for confirming the stress transmission between the units is carried out in parallel, and the joint portion is formed by U in the research report.
Although the same form as the K-shaped joint was applied, the report proved that the reliability was higher than that of the conventional joint method, and the robustness of the reinforced concrete structure formed by the reinforced material surrounded by the thick concrete material was confirmed. Academic harvesting is one of the effects that cannot be overlooked.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view showing a part of the manufacturing method of the present invention.

FIG. 3 is a plan view (A) and a front view (B) showing a joint portion between the bar arrangement units of the present invention.

FIG. 4 is a perspective view of (A), (B) and (C) showing the configuration of the prior art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Distribution muscle 2 Upper muscle 3 Lower muscle 4 Vertical muscle 5 Hollow tube 6 Joint 10 Reinforcement set 11 Vertical muscle 12 Upper muscle 13 Lower muscle S Hollow s Both ends

Continuation of the front page (51) Int.Cl. ⁷ Identification code FI E04G 21/12 105 E04G 21/12 105C (72) Inventor Kazuo Yoshimura 3-17-3 Arae, Sawara-ku, Fukuoka City, Fukuoka Prefecture Ishigaki Heights 2 (72 Inventor Hitomi Dosuga 1-14-1 Osu, Fuchu-cho, Aki-gun, Hiroshima Prefecture 6-chome 189-1 (56) References JP-A-53-55213 (JP, U) JP-A-63-8308 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) E04C 5 / 04 B21F 3/02 B21F 27/10 E04B 5/32 E04B 5/43 E04G 21/12 105

Claims (3)

(57) [Claims] 1. Used for fixing and arranging hollow pipes in a hollow slab method, wherein one rebar is bent in a rectangular shape and wound, and skews while alternately inverting phases vertically in the axial direction. Distributing muscle 1 formed by upper distributing muscle 12, lower dispersing muscle 13, and vertical distributing muscle 11 connecting up and down, and a plurality of hollow tubes arranged in the axial direction of the hollow tube on upper distorting muscle 12. And a plurality of lower ends which are fixed to the lower force bars 13 at intervals of a plurality of hollow tubes arranged in the axial direction of the hollow tube. The hollow tube 5 is inserted and fixed in a section formed almost uniformly by the streak 3 and the longitudinal streak 4 connecting and fixing the upper end streak 2 and the lower end streak 3, except for the sections sa and sb at both ends. The sections sa and sb form a U-shaped joint that projects the distribution muscle 1 in a U-shape, and have a width and a length that can be loaded on the carrier of the transport vehicle. A bar arrangement unit for a hollow slab method, characterized in that: 2. A method for fixing and arranging hollow pipes in a hollow slab method, in which a single reinforcing bar having a predetermined diameter is bent to form a rectangle having a required dimension, and a rectangle having the same shape is further shifted in phase. The procedure of continuously forming is mechanically repeated to form a large number of continuous rectangular aggregates, and the aggregate is stretched in a direction perpendicular to the rectangular surface to be formed, and the phase is alternately inverted up and down in the stretching direction. The upper force distributor 12, the lower force bar 13, and the vertical force bar 11, which connects the upper and lower sides, form the force bar 1, and the upper force bar 12 is formed on the upper surface of the upper force bar 12 in the direction of the hollow tube. A plurality of upper muscles 2 laid laterally and lower armor 13
A plurality of horizontally extending lower end muscles 3 are arranged at the same interval as the upper end muscles, and are tied and fixed to each other.
The hollow tube 5 is inserted and fixed except for the sections sa and sb at both ends into the section formed almost uniformly by the vertical streak 4 that fixes and connects the distribution muscle 1 to the U-shaped section. A method for manufacturing a reinforcing bar arrangement unit for a hollow slab method, characterized by mass-producing a procedure up to a structure for forming a U-shaped reinforcing joint overhanging on a factory. 3. A distributing force bar 1 that is bent and wound in a rectangular shape and alternately inverts the phase up and down and skews, and an upper distributing force line 12 of the distributing force source 1 in the axial direction of the hollow tube. A plurality of hollow pipes are fixed to a plurality of upper muscles 2 which are laid horizontally at intervals of a plurality of hollow pipes arranged at a distance, and a plurality of hollow pipes are axially mounted on the lower muscles 13 of the muscles 1. A plurality of lower streaks 3 that are fixed laterally at intervals of arrangement;
A hollow tube is installed and fixed in a section formed almost uniformly by the vertical streak 4 connecting and fixing the upper end streak 2 and the lower end streak 3, and the hollow tube is connected to the ends sa and sb of the section. The upper and lower bars are not inserted, and the reinforcing bars 1 are extended in a U-shape, so that the reinforcing bar unit 10 having a U-shaped reinforcing joint overlapping with the sa and sb portions of the adjacent units is connected to a construction site by a vehicle. When the necessary number of reinforcing bar sets 10A, 10B... Are arranged on the slab formwork at the site, the ends sa and sb are overlapped, and the joints 6 work to reinforce the reinforcing bars of the units. A hollow slab method characterized in that the target slab structure is integrally formed by casting concrete without connecting the slabs.