JPS6286240A - Reinforced concrete pillar having bundled steel bar barce mounted therein - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a reinforced concrete column with a built-in spring reinforcing bar place, which is mainly intended for reinforced concrete columns that are subjected to heavy loads, such as those in high-rise buildings or high-rise buildings or long-span structures.

BACKGROUND OF THE INVENTION Conventional reinforced concrete columns have a limit in their strength, durability, or tenacity, and have the disadvantage that they are susceptible to cracking if subjected to severe backlash loads from the ground 11. Therefore, important pillars such as those of high-R buildings and large-scale buildings are made of solid-bone ferroconcrete pillars to compensate for their drawbacks.

Problems to be Solved by the Invention Although reinforced concrete columns can generally withstand quite large vertical loads, they are relatively weak against horizontal shear and bending stress due to the ground, etc., as well as tensile loads and may crack. In particular, if a column with shear cracks is subjected to both a vertical load and a horizontal load due to an earthquake, the cracks will increase and there is a risk that the building will suddenly lose its strength and collapse.

As a countermeasure for this, the more hoops (stir bars) are placed densely, the more effective the shear reinforcement will be, which will prevent the rapid spread of fracture after initial cracking and increase toughness. There is a limit in practice, and placing many hoops densely in the overhang will not only increase construction time and increase the number of materials required, but will also impede the filling properties of concrete.

Therefore, important columns such as high-rise buildings, super high-rise buildings, large spans, and large-scale structures that are subject to heavy loads can be made of steel-framed reinforced concrete or steel structures to increase their toughness, so that they can withstand intense backlash loads caused by earthquakes. Generally, it is necessary to prevent the product from suddenly decreasing its yield strength and causing damage. However, compared to reinforced concrete construction, steel-framed reinforced concrete construction requires more labor and construction time, and the amount of steel required increases, resulting in a considerable increase in costs.

In addition, since the steel frame and reinforcing bars are placed in a narrow space, it is not only difficult to construct, but also has poor concrete filling properties, making it difficult to cast high-quality, hard-mixed concrete with high strength.

On the other hand, steel columns are simple and inexpensive when used in small buildings, but they are more expensive for high-rise buildings with heavy loads, and they also require considerable construction costs and labor for fireproof coating and antirust coating.

As a means of resisting horizontal forces, it is effective and common practice to install earthquake-resistant walls and braces at important points in buildings, but these should be installed at locations that do not interfere with the use of the building. This is a constraint on floor planning and design. In addition, because loads are concentrated on shear walls and places during earthquakes and large stresses act on them, reinforced concrete shear walls require many shear reinforcing bars, and steel places use large cross-sections that do not flex and are fireproof. It is also necessary to perform coating and rust prevention, which results in considerable cost.

As an effective means to solve these problems, the applicant previously proposed 4. Assemble wooden steel bars into a three-dimensional truss with the same shape as the present invention,
We developed a reinforced concrete column with main reinforcement and hoops arranged on the outside. This maegashira is an unprecedented new construction method that is intermediate between a steel frame and a reinforcing bar, but the present invention further takes advantage of this construction method so that it can be constructed as an extension of general reinforcing steel work.
This is intended to make it an R1 flight.

Means to solve the problem: Multiple main reinforcements are installed in the column reinforcing bars, which are connected by the four corner main reinforcements, the intermediate main reinforcements placed in the necessary amount between them, and the hoops wrapped around the outer cylinder of the main reinforcements. A set of spring reinforcing bars tied together are arranged diagonally between the internal heights of the upper and lower floor beams so that they intersect at the center height of the pillars, and diagonally to the cross section of the pillars in a three-dimensional truss shape. This spring reinforcing bar placement works effectively and provides excellent seismic performance.

A set of spring reinforcing bars / set as shown in the figure so that they intersect at the center of the internal height Ho of the upper and lower floor beams is regarded as a three-dimensional truss connecting two vertically symmetrical square pyramids with the intersection point as the apex. can be done. Therefore, if an earthquake horizontal force is applied to this column, the fifth
As shown in the figure, in response to an earthquake in the 7 sets of spring reinforcing bars for each direction
It resists with a tensile force of 1 and a compressive force of /b. In both of these cases, the tension and compression forces of the spring reinforcing bars absorb all of the shearing force QS, and the spring reinforcing bars and the concrete surrounding them do not experience any shear, bending, or near-stress stress. I can't convey it again. In this case, by increasing the total cross-sectional area by thickening the reinforcing bars or increasing the number of springs, the shearing force QS borne by the space truss due to the reinforcing bars C can be increased accordingly.

After subtracting this QS from the total shear force Q applied to the column, the remaining q-Q-QS is the four corner main reinforcements J, intermediate main reinforcements J (hereinafter collectively referred to as "main main reinforcements") and hoop 4. The shear force applied to the reinforced concrete (hereinafter referred to as "ILC") section is the same as that of general #C.
Compared to a reinforced concrete column, Q-QS is -, - times smaller, so the shear stress in the concrete is smaller and cracks do not occur (and the need for shear reinforcement is also reduced). become.

In addition, the shear force multiplied by the normal height of the column is the sum of the column head and column base moments, but the bending moment is the same ratio as the shear force mentioned above, and the stress generated in the parallel main reinforcement of the RC section and the concrete. The support of the truss is reduced by the amount it has and becomes smaller.

The above has been described about static stress sharing, but what is particularly important to note is the difference in toughness against large earthquakes. In other words, a typical RC column is hard and has a certain height, so if a shear crack develops in the concrete due to the earth, if the column receives a vertical load and is then subjected to repeated loads due to an earthquake, the electrical equipment will expand and cause sudden damage. As the strength decreases,
This results in a lack of so-called tenacity. On the other hand, in the case of the column according to the present invention Cζ, even if a slight rack is generated in the concrete due to a large earthquake, or even if the tensile force of the parallel main body exceeds the yield point and the column C ζ enters the plastic region Iζ, Since this spring reinforcing bar truss provides resistance in the elastic range, it suppresses the increase in deformation and prevents concrete damage. Even if the deformation becomes large and the axial force of the spring reinforcing bars that refine the truss exceeds the yield load and enters the plastic region,
In addition, since the maximum yield strength is maintained and the yield strength cannot be increased to a large amount of deformation at all times, it is possible to construct a frame rich in tenacity and toughness. This was confirmed through model experiments.

Example @/Figure ζAs shown, the required shape 1ζ is bent into a column reinforcing bar made up of the four corner main reinforcements and the required amount of intermediate main reinforcements J and 7-4 according to the required amount ζ. Four sets of spring reinforcing bars/, which are made up of multiple reinforcing bars, are connected diagonally to the inner vertical height HOIBff of the column between the lower surface of the upper floor beam and the upper surface of the lower floor beam, that is, the floor f, so that they intersect at the center height of the column. In addition, a rectangular truss type vertical truss ζ is installed in a diagonal direction with respect to the beam section.

Figure 2 is an A-A cross-sectional view at the top and bottom ends of the column, and Figure 2XJ is a B-B cross-sectional view at the center height of the column. Then, assemble the pillars so that the center of the pillar is slightly offset from the diagonal of the pillar. The diagram shows J-tree reinforcing bars tied together, but the number of tabs you can place is up to you, and J* can also be used, and four or more bars are possible, and in extreme cases, several to several tens of bars can be used. Thin reinforcing bars or @ wires may be tied or tied together like PC strands or steel cables, and the reinforcing bars to be tied do not necessarily have to be of the same diameter. For example, It is also possible to adjust the total cross-sectional area to the required amount by adding a D-saw.

As for the assembly method, it is possible to incorporate a plurality of reinforcing bars tied together in advance, or it is also possible to assemble the reinforcing bars made of a single piece of wood while transporting them to the site. For reinforcing bar joints, normal reinforcing bar joint methods such as spring joints, gas pressure welding, butt welding, and @knee welding can be used.

Column)-"Even if the column at the F end is anchored at the joint, the effective circumference of the spring reinforcing bar is larger than that of a large-diameter wooden bar with the same cross-sectional area, and the anchorage is correspondingly large. This is advantageous because it has a large adhesion strength with concrete.

However, if the adhesion strength of the spring reinforcing bars alone is not enough to meet the required anchoring force, for example, the anchoring plate can be welded to the spring reinforcing bars to increase the anchoring force, or the restraining force of the so-called panel zone at the column-beam joint can be increased. It is advisable to take measures such as increasing the adhesion strength. Figure @4 is an example of this, in which the spring reinforcing bars are unbound at the column and beam joints and the reinforcing bars/trees are tied apart, and the processing and assembly of the reinforcing bars is a bit complicated. However, the total direct pickle made me cry, so I deviated from it.
1 Constant W @ force increases. Additionally, with the addition of the girder main reinforcing bars, the reinforcing bars are arranged in a truss shape in the panel zone, which increases the mechanical effect on the flow of force and makes the structure even stronger.

After assembling the column reinforcement with the above-mentioned spring reinforcing bar place built in, place the girder main reinforcement 1 in the panel zone and wrap the 7-pipe of the panel zone to create the girder stirrups, small beams, floor slabs, walls, etc. After arranging reinforcement and constructing the necessary formwork, concrete was poured to complete the construction of the Fvr's cap body. In this case, it is effective to use X-shaped spring reinforcing bar places for the girders as well as for the columns, as this can increase the strength and toughness.

The wooden invention was mainly used in Europe for reinforced concrete columns that receive large loads such as columns of high-rise buildings, ultra-high-rise bedding, or long-span structures, but even when used for columns of reinforced concrete buildings with low earthquake resistance, it has no earthquake resistance. This is an effective construction method.

Effect of the invention When wood is invented, there are many advantages as follows.

(b) Compared to a single general reinforced concrete column, a column with much higher strength can be obtained.

Naka) PF suppresses the cracking and deformation of concrete under intense repeated dynamic loads caused by earthquakes, and even if deformation increases, there is little decrease in strength, resulting in a strong and durable building or wj structure.

l/→ Compared to steel-framed reinforced concrete columns, this column requires less material per liter and requires far less processing time, making it much cheaper and faster to construct.

2) Since it can be carried out using ordinary reinforcing bars and with the same level of construction as general steel reinforcement work, construction can be done cheaply in a radius.

Joints and anchorage parts can also be treated in the same way as general Chichisuji.

e) You can freely choose the diameter of the tabane, the number of tabs, and the material of the heating material, so you can easily tighten the place.

It is easy to match the desired value to the desired value, and it is possible to use it for economic purposes.

In addition, it is easy to increase the total cross-sectional area of the place, and the load-bearing force can be easily increased.

(f) Since the three-dimensional truss-shaped spring reinforcing bar place bears the majority of the shear force, the shear force applied to the concrete of the column is reduced, making it difficult for cracks to occur in the concrete, and the 7-pipe for shear reinforcement is also Less is enough.

(g) Unlike steel-framed reinforced concrete construction, there are no steel frames and reinforcing bars, and there are no wide steel frames, so the concrete fills easily and it is easy to use a vibrader. Therefore, it is possible to cast high-quality, hard-mixed concrete with less tonne water, making it easy to use high-rise concrete with high strength and economic utility. It also prevents cracks from occurring due to drying shrinkage, improves the durability of concrete, and allows high-quality structures to be constructed at low cost.

Note: When comparing this Tabane Chichitsumu place with a steel frame place that does not have a built-in part or a place with a single part (including #), the following advantages can be obtained by incorporating ζ.

H) It does not look like a wall or a place that plays a role between pillars.

Also, since it is hidden behind the pillars, it does not become an eyesore and does not become a design constraint.

(A large number of places equal to the number of columns are balanced against the plane of the building (they can be distributed evenly, and the center of gravity of the building and the center of gravity are defeated, preventing the center of gravity from collapsing. If it occurs on the wall, there will be no external bending or stress concentration at that location.

(S) General places are only effective in one direction, either the east-west direction or the north-south direction of a building, but this place is inserted in the diagonal direction of the column cross section, so it is effective against earthquakes in either the east-west direction or the north-south direction. is also effective and twice as effective.

(For general rounded places that are not covered with concrete, and relatively small steel places such as angles, if a compressive force is applied, they will sag with a small amount of force, so the compressive strength can be ignored and they only exist under tension.) Normally, this place is designed with a compression IC, and if a compression IC is also included, a large cross-section H-shape 1 or steel pipe is required.On the other hand, this place is designed with a compression IC made of Mori-no-Chichimu Concrete. It has been confirmed through experiments that it does not buckle when it is 7-inched, and that it is as effective in compression as in tension, even though it is thin.

Therefore, it is twice as effective as the exposed reinforcing bar place that is not built into the column, and the hysteresis curve that represents the relationship between stress and deformation protects against negative cyclic loads up to the elastoplastic region on the compression side. It creates a strong structure and absorbs earthquake energy, making it a durable building.

(w) Steel frame places are fire resistant w1 for large buildings over a certain scale.
1, and the cut ends must be painted, which requires considerable effort and construction costs, but this place, which is built into the C pillar, eliminates the need for such things.

(7) In terms of durability, it is built deep inside the C-type, making it more advantageous than ordinary places.

[Brief explanation of drawings]

Figure 1 is a perspective view showing the assembly of reinforcing bars in the embodiment of the present invention, Figure 2 is an end section of the upper and lower ends of the column, Figure J is a cross-sectional view of the center height of the column, and Figure 4F. is a perspective view of an example of a different constant η method of tabular suspension in columns and beams, and Figure f is a three-dimensional truss C formed by tabular reinforcing bar placement.
ζ This is an explanatory text showing the balance of forces when an earthquake horizontal force is applied. /10. Tubular reinforcing bar 01. Four corner supervisors Jlo, middle supervisor 11. Il Hoop Patent Applicant: Wakabayashi Patent Applicant: Hiroshi Minami -PF Permit Applicant: Konoike Co., Ltd. Kumiyo Moe Hitoike
1) All things life 7 people Figure 1 Figure 4 Figure 3 Figure 5 Xh evening □y, 1il

Claims (1)

[Claims] In the column reinforcing bars constituted by the four corner main reinforcements 2 and, if necessary, the necessary amount of intermediate main reinforcements 3 and hoops 4,
Four sets of spring reinforcing bars 1, which are made by binding multiple reinforcing bars, are arranged in a three-dimensional truss shape diagonally between the internal height H_0 of the upper and lower floor beams and diagonally to the column cross section so that they intersect at the center height of the column. Reinforced concrete columns with built-in tabular reinforcing bars.