JPH0452354A - Pc pole and src pole of cruciform cross section - Google Patents

Abstract

PURPOSE:To prevent cracking due to shear, buckling of each main reinforcing bar, and expansion of concrete by disposing main reinforcing bars near the outside corner portions of each projecting portion, and disposing a first band reinforcing bar around each main reinforcing bar disposed at either of two pairs of opposite projecting portions, and a second band reinforcing bar around each main reinforcing bar disposed at the other pair of opposite projecting portions. CONSTITUTION:Main reinforcing bars 11a, 11b for normal reinforcement are disposed near the outside corner portions of each of four projecting portions S1 or S4. A rectangular band reinforcing bar 12a is disposed outside the main reinforcing bar 11a of each of two projecting portions S1, S2 while in contact with the bar 11a. A rectangular band reinforcing bar 12b is disposed outside the main reinforcing bar lib located on each corner portion of each of two projecting portions S3, S4 whil in contact with the bar 11b. The rectangular band reinforcing bars 12a, 12b are each formed by bending of a long iron bar or the connecting together of shortly cut iron bars. A normal connecting means such as welding, mechanical joint, lap joint, etc., is used for connecting the iron bars constituting the band reinforcing bars 12a, 12b.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to RC columns and SRC columns with cross-shaped cross sections;
In particular, it relates to RC columns and SRC columns with cross-shaped cross sections that include column main reinforcements and tie reinforcements that enhance the binding force of concrete.

BACKGROUND OF THE INVENTION Most conventional reinforced concrete columns (referred to as RC columns in this specification) and steel reinforced concrete columns (referred to as SRC columns in this specification) have a rectangular or circular cross section.

For example, the arrangement of the main reinforcement 1, tie reinforcement 2, connecting reinforcement, etc. of an RC column with a rectangular or circular cross section is as shown in FIGS. 27 and 28. Examples of the arrangement of the steel frame 4, main reinforcement 1, and tie reinforcement 2 of the column are as shown in FIGS. 29 and 30. The mechanical performance of these RC columns and SRC columns with square or circular cross sections has been fully elucidated through numerous experiments.

When constructing a building using columns with a square or circular cross section, the thickness of the wall that is formed integrally with the square or circular column is generally determined to be less than the length of one side of the square or the diameter of the circle. Because they are made smaller, the right-angled corners of square columns and the fan-shaped portions of circular columns protrude into the corners of the room space, and these protrusions impede effective use of the room space. For this reason, there is also a proposal to make the cross-sectional shape of the pillar cross-shaped.

Problems to be Solved by the Invention Since the bending moment generated in a column changes depending on the direction of horizontal load, the shape of the cross section of the column is symmetrical, square,
The overwhelming majority of columns are rectangular or circular, and the main reinforcements 1 are also arranged symmetrically with respect to the center of gravity axis of the column, and the tie bars 2 are arranged around the main reinforcements 1.

The tie reinforcement 1 has the function of preventing cracks due to shear force, and the main reinforcement 1
It is required to have the function of preventing concrete from buckling, preventing concrete from extruding, and ensuring stickiness. Therefore,
In order to fulfill the above function, for example, in conventional RC columns and SRC columns with a square or circular cross section, the 27th
The shape and arrangement shown in FIGS. 30 to 30 are adopted.

By the way, even though it has been proposed to use RC columns and SRC columns with a cross-shaped cross section for the purpose of effectively utilizing room space, regarding the RC columns and SRC columns with a cross-shaped cross section,
The shape, arrangement, etc. of the main reinforcing bars, tie bars, steel frames, etc. have not yet been fully elucidated.

Therefore, RC columns and SRC columns with cross-shaped cross sections are hardly ever put into practical use.

The problem to be solved by this invention is to provide RC columns and SRC columns with a cross-shaped cross section that have sufficient functions as columns. The object of the present invention is to provide an RC column and an SRC column with a cross-shaped cross section that can prevent concrete from extruding.

Means for Solving the Problems The present invention employs the following configuration as a means for solving the problems described above.

The structure of the present invention is such that in an RC column having a cross-shaped cross section, which includes main reinforcements and tie reinforcements, and is composed of a central rectangular portion and protruding portions protruding in all directions from the central rectangular portion, the outer side of each protruding portion is Main reinforcements are arranged near the corners of each, a first tie reinforcement is arranged around each main reinforcement arranged on one of the two opposing protrusions, and a first tie reinforcement is arranged around each of the main reinforcements arranged on the other two opposing protrusions. The RC column has a cross-shaped cross section and is characterized by a second tie reinforcement placed around each main reinforcement.

In a preferred embodiment, the first strap and the second strap are rectangular. The first tie reinforcement and the second tie reinforcement are constructed by joining the ends of reinforcing bars bent into a rectangular shape, but the middle part of the reinforcing bars connected in a rectangular shape is connected with connecting reinforcing bars etc. to form a lattice. You may also use grid-shaped reinforcing bars.

If necessary, main reinforcing bars are also provided at the inner corner portions of the quadrangular portions surrounded by the first straps and the second straps in a plan view of the central rectangular portion of the cross. In addition, reinforcing bars that are effective against axial force are provided at or near the center of the square portion to extend in the longitudinal direction of the column.

The four protrusions of the cross are compressed by arranging main reinforcements at each corner of the square in plan view within the four protrusions of the cross, and by arranging square reinforcing bars around the main reinforcements. For the purpose of intensively reinforcing the area closer to the end of the section, reinforcing bars, brush-shaped reinforcing bars,
Reinforced concrete rods with embedded reinforcing bars are installed to extend in the longitudinal direction of the columns. Also, if necessary,
Reinforcing bars, brush-shaped reinforcing bars, etc. are provided in the portion surrounded by the first ties and the second ties.

In some cases, reinforcing bars are arranged in an RC column with a cross-shaped cross section at an angle with respect to the center line of the cross to withstand high axial forces.

Further, the structure of the present invention includes an SRC in a cross-shaped cross section, including a cross-shaped eight-shaped steel frame, main reinforcement, tie reinforcement, etc., and consisting of a central rectangular portion and protruding portions protruding in all directions from the central rectangular portion. In the columns, main bars were installed near the outer corners of the protruding parts, and a large number of through holes were drilled in each web of the cross-shaped steel frame, and these were installed in one of the two opposing protrusions. A first strap is arranged around the main reinforcement through the through hole, and a second strap is arranged through the through hole around the main reinforcement arranged in the other two opposing protrusions. It is an SRC column with a cross-shaped cross section.

In the case of a cross-shaped SRC column, the main reinforcement may be placed at the inner corner of the quadrangular portion surrounded by the first stirrup and the second stirrup in plan view, or the cross-shaped Rectangular reinforcing strips are placed around each main reinforcement placed at the corners of the rectangle in plan view within the four protrusions.

A cross-shaped steel frame is used as the column steel frame for the cross-shaped SRC column. This steel frame is constructed using H-shaped steel, but L-shaped steel,
It may also be made using a combination of sheet steel, etc. A plurality of through holes for passing the stirrups are made at predetermined positions in the four webs of the cross-shaped steel frame.

If you want to increase the restraint integrity of concrete, you can use main reinforcement placed at the inner corner of the square part surrounded by the first stirrup and second stirrup of the central rectangular part of the cross, Reinforcing bars are installed between the sides of the cross-shaped steel frame web to withstand high axial forces.

The formation of the cruciform cross-section RC and SRC columns of this invention may be cast in place or precast.

Examples RC columns and SRC columns with a cross-shaped cross section of the present invention are:
For example, it is used as a cross-shaped pillar c1 of a building with a pillar arrangement as shown in FIG.

The cross-sectional shape of the cross-shaped pillar c1 is as shown in FIG.
When the two rectangles P and Q are positioned approximately at the center of their center lines P1 and Ql so that their center lines intersect at right angles, the cross shape formed by the composition of the two rectangles P and Q is Shape, that is, a central rectangular portion R and rectangular protrusions s1, s2, s that protrude in all directions from this central rectangular portion R.
Match 5 to the shape consisting of 3 and s4. two rectangles P
The lengths of the long sides and short sides of , Q are determined as appropriate depending on the building etc. to be constructed.

An RCCl2O embodiment of the present invention will be explained using FIGS. 2 to 19.

The arrangement of the main reinforcing bars of the RC column, the shape of the stirrup bars, the basic form of their arrangement, etc. are shown in Figs. 2 to 12.

The basic model shown in FIG. 2 has a main bar 11a of an ordinary reinforcing bar near the outer corner of the four protruding parts s1 to S4,
llb is arranged, and the main reinforcements 11a, 11b and the main reinforcements 11a, l
An appropriate number of main reinforcing bars are also provided between the lbs as necessary. Two vertically opposing protrusions S1 in FIG.
A rectangular tie reinforcement 12a is provided on the outside of the main reinforcement 11a of S2 and in contact with the main reinforcement 11a. Furthermore, rectangular band reinforcements 12b are arranged outside and in contact with the main reinforcements 11b at each corner of the two horizontally opposing protrusions S3 and S4 in FIG. Intersection 13 of tie bars 12a and ties 12b and main bars 11a, llb
An appropriate number of main reinforcing bars are also arranged inside the straps 12a, 12b between them, as necessary.

The rectangular ties 12a and 12b are used to bend long iron bars,
It is formed by connecting short iron bars. Strap 12
To connect the iron rods composing parts a and 12b, ordinary connecting means such as welding, mechanical joints, lap joints, etc. are used.

In addition, the main reinforcements 11a, llb, llc and the tie reinforcements 12a,
In addition to ordinary reinforcing bars, the material for 12b is P.
C steel rods, high tensile strength fibers, or a combination of these can also be used.

The basic type shown in Fig. 3 has L-beams lid, lle instead of the main bars 11a and llb of the ordinary reinforcing bars in Fig. 2.
This is what was used. In addition to L-shaped steel, T-shaped steel,
L-shaped steel, channel steel, etc. can also be used.

The basic type shown in FIG. 4 is the basic type shown in FIG.
A main reinforcement 11f is added to the inner corner of each of the straps 12a and 12b at the intersection 13 of the ties 12a and 12b.

The basic type shown in FIG. 5 is the basic type of tie bar 12 shown in FIG.
A reinforcing bar 11g that is effective against axial force is placed at the center of a rectangle connecting the four intersections 13 of a and 12b.

As the reinforcing bar 11g, L-shaped steel, T-shaped steel, L-shaped steel, channel steel,
PC steel rods, high-tensile fibers, etc. may be used.9 The basic type shown in Figure 6 is similar to the basic type shown in Figure 2.
For the rectangular part connecting the four intersections 13 of a and 12b, a rectangle that is /lX smaller than this rectangle is assumed, and at the corner of the assumed rectangle, a section steel 11h that is effective against axial force is attached along the longitudinal axis of the column. It is arranged so as to extend in the direction. Instead of the L-shaped steel 11h, a T-shaped steel, an L-shaped steel, a channel steel, a PC steel bar, a high-tensile fiber, etc. can be used.

In the basic form shown in Figures 2 to 6, the ties 12a, 1
2b are arranged at intervals in the longitudinal direction of the column 10 around the main reinforcements 11a, llb, llc, etc. extending in the longitudinal direction of the column 10, as shown in FIG. However, the tie 12a
There may also be cases where the tie bars 12b and the tie bars 12b are arranged in an overlapping manner.

The basic type shown in FIG. 8 is a type to be adopted when it is desired to intensively reinforce the four protrusions S1 to S4 of the cross shape.
Main reinforcements 11a, llb, 11c are provided at the corners of the assumed rectangle of each protruding portion of the rectangular cross section.

11i, and reinforcing bars 12c made of rectangular iron bars or the like are arranged around these main bars.

The tie bars 12c are arranged at intervals in the longitudinal direction of the column. This basic shape is rarely used alone, but is often used in combination with the basic shapes shown in FIGS. 2 to 6.

The basic types shown in FIGS. 2 to 6 and 8 may be used in combination.

The applied type shown in FIG. 9 is a combination of the basic type shown in FIG. 2 and the basic type shown in FIG.

In this applied type, as shown in FIG. 10, tie bars 12a and ties 12b are arranged at intervals in the longitudinal direction of the column 10,
In addition, a strap 12c is arranged between the strap 12a and the strap 12b.

The basic type shown in Figures 11 and 12 is based on the cross-section of the RC column in order to increase the restraint integrity of concrete when high axial force is applied in the adoption of the basic type shown in Figures 2 to 6. It has diagonal reinforcing bars inside. 11th
The type shown in the figure is an application of the basic type shown in FIG. 2, and reinforcing bars 14a,
14b is arranged, and the bent portions of the ends of the reinforcing bars 14a and 14b are applied to the main reinforcing bars 11a and llb. The type shown in FIG. 12 is an application of the basic type shown in FIG.
c, 14c, and if necessary, reinforcing bars 14c, 1
This is an example in which the bent portion of 4c is applied to each main reinforcement 11f. In addition,
The reinforcing bars 14a, 14b, and 14c are arranged at intervals in the longitudinal direction of the column 10.

The mold shown in FIGS. 13 and 14 is a modification of the mold shown in FIG. 9, and is used to lengthen the four cruciform protrusions S1 to S4. In such a case, when a high axial force is applied and a large bending stress is applied, a large compressive force is applied to the portions closer to the ends of the four protrusions S1 to S4. Therefore, reinforcement is required to intensively restrain the concrete near the ends.

In order to strongly restrain the portion from the end, the 15th
A lattice reinforcing bar as shown in Figures 1 to 17 is used.

The welding grid 12d shown in FIG. 15 consists of two long iron bars 12.
The ends of d1 and two short iron bars 12d2 are welded to form a rectangular shape, and the ends of two connecting iron rods 12d are welded to the middle part of the rectangular shape to form a lattice shape. This is what I did. The lattice reinforcing bars shown in Fig. 16 are shown in Fig. 16 (
A long rectangular strap 12e1 formed by bending the iron rod in A) and a short rectangular strap 12e2 formed by bending the iron rod in FIG. 16(B) are overlapped and connected in a lattice shape.

The lattice-like ties shown in Fig. 17 are attached to two parts from the ends of the long rectangular ties 12f formed by bending the iron bar shown in Fig. 17 (A), and from the ends shown in Fig. 17 (B). Short connecting reinforcing bars 12f2 each having a hook portion are hung thereon to form a lattice shape.

The mold shown in FIG. 13 includes main bars 11a, llb, 11c, l.
lf and lli are arranged, and a large number of welding grids 12d are hung on these main reinforcements at intervals in the longitudinal direction. The type shown in Figure 14 is.

Main bars 11 of each protrusion S1 to S4 of the mold shown in FIG.
Reinforcement reinforcing bars 11g, which are effective against axial force, were arranged to extend in the longitudinal direction of the column in the rectangular part surrounded by a, llb, lie, and lli and the rectangular part surrounded by each main reinforcement 11f. It is something. Examples of the reinforcing bars 11g include regular reinforcing bars, PC steel bars, steel pipes, square steel, and L
Shaped steel, T-shaped steel, H-shaped steel, channel steel, high tensile strength fibers, etc. are used.

Further variations of the RC column are shown in FIGS. 18 and 19. FIG. 18 shows a rectangular portion surrounded by the main reinforcements 11a, llb, llc of each of the protrusions S1 to S4 and a square portion surrounded by each of the main reinforcements 11f of the central rectangular portion R, arranged on an imaginary circle. Many main bars 11j
and cup-shaped reinforcing bars 16 formed by arranging tie bars 12d around them. In FIG. 19, instead of the cup-shaped reinforcing bars shown in FIG. 18, a rod-shaped body 17 made of reinforced concrete and formed by embedding reinforcing bars is provided.

Next, an embodiment of the SRC column of the present invention will be described using FIGS. 20 to 25.

The cross shape of the pillar 20 is the same as the RCCl2O cross shape of the previous embodiment. A cross-shaped eight-shaped steel frame will be used for the 2OA pillar steel frame.

In the basic type shown in FIG. 20, the arrangement of the main reinforcements 21a and 21b is the same as the arrangement of the main reinforcements 11a and llb in FIG.
, 12b.

The differences from the one in Figure 2 are that a cross H-shaped steel frame 20A with through holes for passing the stirrups 22a and 22b is used, that the stirrups 22a and 22b are divided into at least two parts, and that the cross H-shaped steel frame 20A and tie bars 22a,
22b, etc.

Four webs 20A as a cross H-shaped steel frame 20A
1 with through holes 20A1a through which the stirrups 22a, 22b are passed at intervals in the longitudinal direction, and the stirrups 22a, 2
2b, at least two parts 22a0.22a2
．． 22b1.22b2 is used.

One portion 12a1.1 of the ties 22a, 22b
2b, through each through hole 20A1 of each web 20A1.
a, and its end and the end of the other part 22a2.22b2 are connected by the connecting means 18, and an integral strap 22a,
22b.

Note that it is also possible to use a U-shaped reinforcing bar formed by bending an iron bar into a U-shape as the tie bar, and attach the ends of the U-shaped reinforcing bar to each web. In this case, for example, the ends of the webs are passed through the through holes of each web, and nuts are screwed into the ends to prevent them from slipping out.

The basic type shown in FIG. 21 is a main bar 21a with a normal circular cross section.
, 21b, L-shaped steels 21d and 21e are used. Instead of this L-shaped steel, T-shaped steel, H-shaped steel,
Channel steel etc. can also be used.

The basic mold shown in FIG. 22 is obtained by adding main reinforcements 21f to the inner corners of the rectangular portion surrounded by the ties 22a and 22b of the central rectangular portion R of the basic mold shown in FIG. be.

The basic model shown in FIG. 23 is adopted when it is desired to intensively reinforce the four protruding parts of the pillar 20, and the four protruding parts S1 to S4 of the cross shape are assumed to have a rectangular shape, and the rectangular shape is Main reinforcing bars 21a, 21b, 21c, and 21i are arranged at the corners, etc., and rectangular reinforcing bars 22c are arranged around these main reinforcing bars.

For example, the reinforcing ties 22c are separated into two parts,
One end of the strap 12c is passed through each through hole 20A1b of each web 20A1, and the end is connected to the other end of the connecting means 1.
8, connect and arrange.

The basic type shown in FIG. 23 is rarely used alone, and is usually used in combination with other basic types.

The basic type shown in Figure 24 is the same as the basic type shown in Figure 20.
This is a combination of the basic model shown in Figure 3. Stirrup 2
2c is a steel frame 20 similar to the tie reinforcement 12C shown in FIG.
Each strap 22a, 2 arranged at intervals in the longitudinal direction of A
Place it between 2b.

The basic type shown in Fig. 25 is based on the basic type shown in Fig. 22, and in order to increase the restraint integrity of concrete when high axial force is applied, diagonal reinforcing bars are installed in the cross section of the SRC column. 24 is included. For example, the diagonal reinforcing bar has a hook 24a at one end and a straight part 24 at the other end.
Using the dogleg-shaped reinforcing bar 24 b, attach the hook 24a to the main bar 21.
f, and the straight portion 24b is connected to each web 20A of the steel frame 20A.
Place it in line with 1. The straight portion 24b is welded to the web 20A1 as necessary.

As the coupling means 18, for example, ordinary means such as welding, joints, and wire binding are used.

In addition, even in the basic type shown in FIGS. 20 to 25, the main reinforcements 21a, 21b and the main reinforcements 21a,
The inside of the straps 12a and 12b between 21b and the strap 1
An appropriate number of main reinforcements are arranged inside the ties 12a and 12b between the intersection 13 of the ties 2a and the ties 12b and the main reinforcements 11a and llb.

Effects of the Invention The RC column of the present invention has main reinforcements arranged near the outer corners of each of the four protrusions of the cross shape, and around each main reinforcement arranged on one of the two opposing protrusions. Since the first tie reinforcement is placed and the second tie reinforcement is placed around each main reinforcement placed on the other two opposing protrusions, cracks will not occur even if a large shearing force is applied. It is possible to prevent buckling of the main reinforcing bars and prevent concrete from protruding without causing any problems.

By placing reinforcing bars around the main reinforcement placed at the rectangular corners of the four protruding parts of the cross shape in plan view, the concrete in each protruding part can be intensively restrained. R
Placing the reinforcing bars in the C column at an angle can further increase the restraining integrity of the concrete.

In addition, the SRC column of the present invention uses a cross-H-shaped steel frame with main reinforcements arranged near the inner side of the outer corners of the cross-shaped protrusion, and through-holes formed in each web of the cross-H-shaped steel frame. A first strap is provided through the through hole around the main reinforcing bars arranged on one of the two opposing protrusions, and a first strip is provided around the main reinforcing bars arranged on the other two opposing protrusions. Since the second reinforcement is provided through the hole, no cracks will occur even if a large shearing force is applied, and the concrete can be completely prevented from protruding.

By placing reinforcing bars around the main reinforcements placed at the corners of the rectangle in plan view within the four protrusions of the cross, the concrete in each protrusion can be intensively restrained. The main reinforcement arranged inside the corner of the square part surrounded by the first stirrup and the second stirrup in a plan view of the central rectangular part of and the side surface of the cross H-shaped steel frame web. Placing reinforcing bars in between further increases the restraining integrity of the concrete and allows it to withstand high axial forces.

[Brief explanation of drawings]

Figures 1 to 18 show examples of cross-shaped RC columns, and the plan view of the cross-shaped column in Figure 1, Figures 2 to 6, and Figure 8 show the main reinforcement and tie reinforcements. A plan view of the basic type of arrangement, Figure 7 is an elevation view of the main reinforcement and tie bars in Figure 2, Figure 9
The figure is a plan view of an applied version of the arrangement of main bars and stirrers, Figure 10 is an elevation view of the main bars and stirrers in Fig. 9, and Figures 11 and 12 are the arrangement of main bars, ties, and reinforcing bars. 13 and 14 are plan views of other applied types, FIG. 15 is a plan view of the welded grid, and FIGS.
) is a plan view of rectangular reinforcing bars for making lattice ties, and Figure 17 (A
) and (B) are plan views of rectangular reinforcing bars and connecting reinforcing bars that make lattice bars, Figs. 18 and 19 are plan views of other applied types, and Figs. 2o to 25 are cross-shaped SRC columns. 20 to 23 show examples of steel frames,
Fig. 24 and 25 are plan views of the basic type of arrangement of main reinforcements and stirrups, Fig. 26 is a plan view of an applied version of the arrangement of steel frames, main reinforcements and stirrups, and Fig. 26 is a cross-shaped RC column of this invention, SRC. Schematic plans of buildings using columns, 27th WI and 28th
The figure is a plan view of the arrangement of the main reinforcement and tie bars of a conventional RC column, and FIGS. 29 and 30 are plan views of the arrangement of the main reinforcement and tie bars of a conventional SRC column. In the figure, 10 is an RC column, lla to llc, IIf, 1
1i, 21a to 21c, 21f and 21i are main reinforcements, 11g is reinforcing bars, llh is L-shaped steel, 12a, 12b, 2
2a and 22b are stirrups, 12c and 22c are reinforcing stirrups, 13 and 23 are intersections, 14a, 14b, 14c
and 24 are reinforcing bars, 16 are brush-shaped reinforcing bars, 17 are reinforced concrete rods, 18 are coupling means, 20 are SRC columns, 20A are cross H-shaped steel frames, 20 A 1 a and 20 A1b are through holes, and R is The central rectangular portions S1 to S4 are protrusions. Figure 26

Claims (1)

[Scope of Claims] 1. In an RC column having a cross-shaped cross section, including main reinforcements and tie reinforcements, and consisting of a central rectangular portion and protruding portions protruding in all directions from the central rectangular portion, each protruding portion Main reinforcements are arranged near the outer corners of each, a first tie reinforcement is arranged around each of the main reinforcements arranged on one of the two opposing protrusions, and a first tie reinforcement is arranged around each of the main reinforcements arranged on the other two opposing protrusions. A second reinforcement is placed around each main reinforcement placed in the
An RC column with a cross-shaped cross section, characterized by the fact that it is equipped with tie bars. 2. Claim 1, characterized in that the main reinforcement is disposed at the inner corner of the intersection of the first strap and the second strap in plan view of the central rectangular portion of the cross shape. An RC column with a cross-shaped cross section. 3. A reinforcing bar that is effective against axial force is installed in the center or near the center of the square part surrounded by the first stirrup and the second stirrup in a plan view of the central rectangular part of the cross. The RC column with a cross-shaped cross section according to claim 1 or 2, characterized in that the RC column is arranged to extend in the longitudinal direction. 4. Claims 1 to 3, characterized in that main reinforcing bars are provided at each corner of a rectangle in plan view within the four protruding portions of the cross, and reinforcing tie bars are provided around the main reinforcing bars. An RC column with a cross-shaped cross section as described in any one of the above. 5. The RC column with a cross-shaped cross section according to claim 4, wherein the first stirrup bars and reinforcing stirrup bars and the second stirrup bars and reinforcing stirrup bars are composed of lattice reinforcing bars. 6. Rectangular reinforcing bars are arranged around each main reinforcing bar placed at each corner of the square in plan view in the four protrusions of the cross, and the main reinforcing bars are surrounded by the rectangular reinforcing bars. The first strap and the second strap in plan view within the part or central rectangular part
The cross shape according to any one of claims 1 to 5, characterized in that reinforcing bars or the like are arranged extending in the longitudinal direction of the column in the quadrangular portion surrounded by the ties. RC column in cross section. 7. The cruciform shape according to any one of claims 1 to 6, characterized in that reinforcing bars are arranged in the columns of the cruciform cross section so as to be inclined with respect to the center line of the cruciform shape. RC column in cross section. 8. In an SRC column with a cross-shaped cross section, including a cross H-shaped steel frame, main reinforcement, tie reinforcement, etc., and consisting of a central rectangular part and a protruding part that protrudes in all directions from the central rectangular part, the protruding part Main reinforcements are placed near each outer corner,
A large number of through holes are drilled in each web of the cross H-shaped steel frame, and a first tie reinforcement is provided through the through hole around the main reinforcement provided on one of the two opposing protrusions,
An SRC column having a cross-shaped cross section, characterized in that second tie reinforcements are arranged through the through holes around the main reinforcements arranged on the other two opposing protrusions. 9. A claim characterized in that the main reinforcing bars are arranged at the inner corners of the quadrangular part surrounded by the first straps and the second straps in a plan view of the central rectangular part of the cross shape. The SRC column having a cross-shaped cross section according to item 8. 10. According to claim 8 or 9, main reinforcements are arranged at each corner of a rectangle in plan view within the four protrusions of the cross shape, and reinforcing ties are arranged around the main reinforcements. An SRC column with a cross-shaped cross section. 11. The main reinforcement is arranged at the inner corner of the square part surrounded by the first stirrup and the second stirrup in a plan view of the central rectangular part of the cross, and each of the cross H-shaped steel frames The SRC column with a cross-shaped cross section according to any one of claims 8 to 10, characterized in that reinforcing bars are provided between the side surfaces of the web and the main bars at the corners.