JPH02248582A - Continuous layer, earthquake-proof wall structure for high-storied structure - Google Patents

Abstract

PURPOSE:To raise the effectiveness of earthquake-proofing design by a method in which the accompanying columns of the lower floor of a continuous layer, earthquake-proof wall are formed in RC or SRC ones wound with steel tube and integrated through a share resistor part with the wall concrete. CONSTITUTION:The accompanying columns A of the lower floors in a continuous layer, earthquake-proof wall B are formed by arranging main reinforcing bars 2, core reinforcing bars 3, and hoops 4 in an angular steel tube 1 and then by placing high-strength concrete 5 into it. Shear keys 6 as shear resistors are welded to the periphery of the tube 1 to integrate the columns A with the reinforced concrete earthquake-proof wall B. The strength and toughness of the columns A of the lower floors can thus be improved, raising the effectiveness of a earthquake-proof design.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a continuous shear wall structure in a high-rise building.

(Prior Art) Conventional multi-layer shear walls are generally made of cast-in-place concrete, as shown in Figures 13 and 14.
) and ancillary pillars (b) are cast at the same time.

The accessory columns are generally made of reinforced concrete or steel-framed reinforced concrete, and the columns are covered with cover concrete, and the restraining force of the concrete against the column's axial compressive force is determined by the hoop reinforcement (b )
It is structured so that it can be obtained by

In the figure, (a+)(at) is a vertical wall reinforcement and a horizontal wall reinforcement, and (C) is a beam.

(Problems to be Solved by the Invention) The following two stresses occur in a multi-layer shear wall placed in a high-rise building.

(i) Under vertical load, a compressive axial force acts on the attached column. This axial force is generally larger than that of other columns.

(ii) Under earthquake load, shearing force is generated in the wall plate,
At the same time, compressive axial force and tensile axial force generated by bending moments act on the attached columns of the lower floors alternately.The toughness of this type of shear wall under seismic loads is mainly ensured by bending deformation of the lower floors. , this bending deformation is determined by the toughness of the attached column, especially the toughness of the column on the side receiving the compressive force.

Therefore, in the conventional multi-layer shear wall, when the compressive force (axial force during vertical load + axial force during seismic load) applied to the attached column reaches the uniaxial compressive strength of the attached column or more, the Because the toughness decreases rapidly and as a result, the bending toughness also decreases.
It becomes difficult to ensure the seismic performance of seismic walls.

The present invention was proposed in view of the problems of the prior art, and its purpose is to improve the strength and toughness of attached columns on the lower floors of multi-story shear walls in high-rise buildings, and to The purpose is to improve the effectiveness of earthquake-resistant design of earthquake-resistant walls.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the multi-story shear wall structure in a high-rise building according to the present invention is such that the attached columns on the lower floor of the multi-story shear wall are made of steel pipe-wrapped RC or SRC. It is constructed of pillars, and the additional pillars and wall concrete are integrated through shear resistance members attached to the steel pipes.

(Function) According to the present invention, as described above, by configuring the accessory columns on the lower floor of the multi-story shear wall from steel pipe-wrapped RC or SRC columns, the compressive toughness of the accessory columns is improved, and the accessory columns are The bending toughness of the shear wall integrated with the column via the shear resistance member attached to the outer periphery of the steel pipe is also significantly improved.

(Example) The present invention will be described below with reference to the illustrated embodiments.

In Figures 1 and 2, (A) is an auxiliary column made of steel pipe-wrapped RC construction for a continuous shear wall in a high-rise building, with main column reinforcement (2) and core column reinforcement (3 ) and stirrup (4
) are reinforced and a high-strength concrete outer reit (5) is placed.

In addition, steel pipe-wrapped RC columns have steel pipes wrapped around the outer periphery instead of the hoops of conventional RC columns, and are edged by the column capital and column base.

X in the figure is this edge cutting part.

The attached column (A) is a shear key (forming the shear resistance member) that is implanted by welding on the outer peripheral surface of the steel pipe (1).
6) is integrated with the reinforced concrete shear wall (B).

In the figure, (7) is the wall vertical reinforcement, (8) is the wall horizontal reinforcement, (9) is the width stop reinforcement, (lO) is the wall concrete, and (C) is the beam.

Note that a circular steel pipe may be used instead of the square steel pipe (1) in the accessory column (A).

In the above example, the attached column (A) was made of a steel pipe-wrapped RC column for the purpose of improving the compressive toughness due to compressive axial force. When improved, the bending toughness of the shear wall (B) is significantly improved.

Here, a steel pipe-wrapped RC column constituting the attached column (A),
The SRC pillars will be explained.

In a steel pipe-wrapped RC column or SRC column, the steel pipe is cut off at the column capital and column base, so that the steel pipe is not directly loaded in the axial direction (particularly compressive axial force).

On the other hand, in conventional steel pipe concrete columns, the steel pipe is connected to the horizontal members at the column capital and column base, and axial force is directly applied to the steel pipe.

Figures 6 to 8 show experimental examples of the above-mentioned steel pipe-wrapped RC columns, SRC columns, and steel pipe concrete columns.
In the steel pipe concrete column shown in Figure 6, which shows an RC column, compressive axial force is applied to the steel pipe from the start of loading, so when the maximum load is applied, local buckling of the steel pipe is caused as shown in y in Figure 8. After this, it becomes difficult to ensure toughness.

In contrast, steel pipe-wrapped RC columns or SRC columns shown in Fig. 7
In column construction, steel pipes are not directly loaded in the axial direction (particularly compressive axial force), so the steel pipes mainly play the role of restraining the internal concrete by tensile resistance in the column circumferential direction.

FIG. 9 shows the difference in deformation characteristics under load between the steel pipe concrete column shown in FIG. 6 and the steel pipe-wrapped RC column or SRC column shown in FIG. 7.

Next, the effects of the present invention will be explained in detail with reference to FIGS. 10 to 12.

Figure 10 shows curves showing the relationship between axial load and axial compressive strain for various columns, where K+ indicates the case of a conventional reinforced concrete column, and h indicates the case of a steel pipe-wrapped RC structure using square steel pipes or SRC. Indicates the case of pillar construction, K and I indicate the case of steel pipe-wrapped RC construction or SRC construction pillar using circular steel pipes,
This figure shows that steel pipe-wrapped RC or SRC columns have greater compressive toughness due to compressive axial force than conventional reinforced concrete columns.

In the figure, , , and 2 are respectively described later. Corresponds to tc.

Figure 11 shows the strain distribution in the cross section of the shear wall when axial force N, bending moment M, and shear force Q are applied to the multi-layer shear wall during an earthquake, and ゎε in the figure. is the compressive strain 1 of the conventional reinforced concrete column on the compression side, and ε0 is the tensile strain of the column reinforcement of the conventional reinforced concrete column on the tension side.1. ε8 is the tensile strain of the wall reinforcement associated with this.

By making the attached column a steel pipe-wrapped RC or SRC column using square steel pipes or circular steel pipes, the compressive strain of the column concrete becomes Ct'CIC' c, and the tensile strain of the column reinforcement becomes Lg'C+tffi'. In addition, ε′
1. tε″0 is the tensile strain of the wall reinforcement.

Therefore, as shown in Figure 11, the bending curvature of the shear wall is φ'Y or φ#, rather than φ8 in the case of conventional reinforced concrete columns.
Increases to 0.

Figure 12 shows the relationship between bending moment and bending curvature of shear walls, where K11 has conventional reinforced concrete attached columns, and 172 has steel pipe-wrapped RC or SRC attached columns using square steel pipes. , gl indicates a case where a steel pipe-wrapped RC structure or SRC structure is attached to a strap using a circular steel pipe. By using steel pipe-wrapped RC or SRC columns, the compressive toughness of the attached columns is improved, and by increasing the bending curvature of the shear wall, the bending toughness of the shear wall is greatly improved.

When high-strength concrete has no lateral restraint,
After the maximum compressive strength is reached, rapid fracture occurs, so toughness cannot be expected. However, as in the above embodiments, by coating an appropriate amount of steel pipe, a significant improvement in compressive toughness can be expected. (See Figure 10) In general, members other than accessory columns and other than corner pillars have a maximum of 400
Since it is sufficient to use concrete having a compressive strength of about 500 kg/cj, it is not reasonable to separately cast concrete with a higher strength than that in place, and it is better to use PC.

Figure 3 shows another embodiment of the present invention, in which main bars (2) and tie bars (4) are arranged inside a square steel pipe (1) and filled with high-strength concrete (5). By means of a shark (6) welded to the square steel pipe (1) in a steel pipe-wrapped RC attached column in which a cast-in-place reinforced concrete part (11) is provided in a hollow part provided in the column core of a precast steel pipe concrete column, It is integrated with the reinforced concrete shear wall (B).

In the figure, parts equivalent to those of the above embodiment are given the same reference numerals.

In the embodiment shown in Fig. 4, a steel column (12) is arranged inside the square steel pipe (1) instead of the core column reinforcement (3) in the embodiment of Fig. 1, and high-strength concrete (5) is installed. Casting and winding steel pipe S
It is made up of attached columns made of RC construction.

In the drawings, parts equivalent to those of the above embodiments are given the same reference numerals.

In the embodiment shown in Fig. 5, the main column reinforcement (2
) and stirrups (4) to form high-strength concrete (5).
A column steel frame (13) is installed in the hollow part provided in the column core of the precast steel pipe concrete column loaded with steel pipe S.
It is made up of RC attached pillars.

In the figure, parts equivalent to those of the above embodiments are given the same reference numerals.

(Effects of the Invention) As described above, the present invention improves the compressive toughness of the attached column by configuring the attached column on the lower floor of the multi-story shear wall from a steel pipe-wrapped RC structure or SRC column. The bending toughness of the shear wall integrated with the column via the shear resistance member attached to the steel pipe is greatly improved, and the effectiveness of the seismic design of the multilayer shear wall is improved.

The invention as claimed in claim 2 achieves a significant improvement in compressive toughness by pouring high-strength concrete into the steel pipes of the steel pipe-wrapped RC construction or SRC construction accessory columns, thereby restraining the concrete from the lateral direction by the steel pipes. It is something.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional plan view showing one embodiment of the multi-story shear wall structure in a high-rise building according to the present invention, Fig. 2 is a longitudinal cross-sectional view thereof, and Fig. 3 is a diagram showing another embodiment of the present invention. cross-sectional plan,
FIGS. 4 and 5 are cross-sectional plan views of an accessory column portion in still another embodiment of the present invention, and FIGS. 6 and 7 are front views of a steel pipe concrete column and a steel pipe-wrapped RC or SRC column, respectively. , Figure 8 is a front view showing the state of deformation of a steel pipe concrete column due to compressive axial force, Figure 9 is a diagram showing the relationship between the axial force and axial deformation of each column, and Figures 10 to 12 are the main views. Figure 10 is a diagram showing the relationship between the axial compressive strain of the attached column and the axial load, Figure 11 is a strain distribution diagram of a cross section of a shear wall, and Figure 12 is a diagram showing the bending of the shear wall. FIGS. 13 and 14, which show the relationship between moment and bending curvature, are partially vertical front views taken in a transverse plane and showing conventional multi-layer shear wall structures, respectively. (^)...Additional column, (B)...Shear wall, (1
)...Square steel pipe, (5)...High-strength concrete, (6)...Sharkey Agent Patent attorney Shige Okamoto 2 people outside the JGT theory! P12 sq figure piro senka 11 agony

Claims (2)

[Claims] (1) Ancillary columns on the lower floor of the multi-story shear wall are composed of steel pipe-wrapped RC or SRC columns, and the ancillary columns and wall concrete are integrated through shear resistance members attached to the steel pipes. A continuous shear wall structure for high-rise buildings characterized by (2) Claim 1, wherein the steel pipe-wrapped RC or SRC attached pillar is constructed by pouring high-strength concrete into a steel pipe.
Continuous shear wall structure in the mentioned high-rise building.