JPH0443130B2 - - Google Patents

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention relates to structures constituting the framework of buildings,
In particular, the present invention relates to a structure that is effective when applied to the framework of a high-rise building of the tube frame type.

``Prior Art'' A tube frame as shown in FIG. 5 is known as a frame structure for high-rise buildings made of steel frames or steel-framed reinforced concrete. This frame type consists of an X-direction frame 3 composed of columns 1 and beams 2,
3 and the Y-direction frames 4, 4, a tube-shaped (cylindrical) structure 5 that constitutes the outer peripheral frame of the building is constructed, and only this structure 5 bears the seismic force. . With such a frame type, the interior of the structure 5 can be column-free and beam-free, and an internal space with a high degree of freedom in plan planning and excellent livability can be obtained.

In such a tube structure, the structure 5
In order to resist seismic force as a whole, the seismic force is borne not only by the frame parallel to the applied direction but also by the frame perpendicular to it. This is a major difference from conventional frame structures in which the earthquake force is borne only by the frame parallel to the direction of the earthquake.

For example,
When an earthquake force in the direction is applied, a part of the axial force generated in the X-direction frames 3, 3 parallel to it is transmitted to the Y-direction frames 4, 4 perpendicular to it,
Both sides now bear the axial force during an earthquake.
In this case, each column 1 of the X-direction frames 3, 3...
In response to pull-out force or reaction force from the ground, an axial force is generated in the direction shown in the lower part of Figure 5, but these stresses are also transmitted to the Y-direction frames 4, 4, and each of the columns 1... An axial force as shown in the lower part of Figure 5 will be generated. If the tube frame is not used, such stress will not occur in the orthogonal frame. Figure 6 shows how each column 1 of the Y-direction frame (orthogonal frame) 4 responds to such X-direction seismic force.
It shows the axial force distribution state of stress generated in
As is clear from this figure, the axial force is greater in the outer columns.

If the direction of the seismic force is in the Y direction as indicated by the dashed arrow in Figure 1, the Y direction frames 4, 4 which are parallel frames in that case are changed from the X direction frames 3, 3 which are orthogonal frames. Similarly, stress will be transmitted to .

By the way, in order for the stress at the time of an earthquake as described above to be effectively transmitted from the parallel frame to the orthogonal frame and to make it possible for the entire structure 5 to bear the earthquake force, it is necessary to It is necessary that the rigidity is sufficiently high. Since the direction of the seismic force cannot be limited to a specific direction, in the tube frame structure 5, each frame 3, 3, 4, By making the column spacing (span) of No. 4 small and the beam size large, the rigidity of the beams No. 2 is made high.

``Problems to be solved by the invention'' However, increasing the beam dimensions as described above not only increases the floor height and increases costs, but also causes problems such as violating building height restrictions. .

For this reason, it is possible to transmit stress by providing braces on each frame 3 and 4 without increasing the beam size, but in this case, the position and size of openings such as windows in the outer wall The problem is that it is restricted. In addition, in order to prevent an increase in floor height, it has been considered that beams 2... should not be installed on all floors, but instead installed every other floor, that is, at intervals of two floors, but in this case, There is a problem that the structural floor height doubles, the bending moment of the columns 1 increases, and the horizontal rigidity of the structure 5 decreases, which is not realistic.

This invention was made in view of the above circumstances, and aims to provide a structure that can reduce the amount of steel frames and reduce construction costs.

``Means for Solving the Problems'' The present invention utilizes a plurality of columns erected at positions on the outer periphery of a multi-story building in a plan view, and beams spanned between the columns. A constructed building structure, wherein some or all of the beams are provided between the pillars at the floor of the building at an interval of two layers of the building, and ,
The beams provided between adjacent columns are characterized by being offset from each other by one layer of the building.

"Example" Hereinafter, an example in which the present invention is applied to a high-rise apartment building will be described with reference to FIGS. 1 to 4. FIG. 1 is a perspective view showing the overall schematic configuration of the structure 10 that constitutes the outer peripheral frame of this building, and FIG. 2 is a partial elevation view thereof.
FIG. 3 is a partial sectional view.

This building has a tube frame similar to the conventional structure 5 mentioned above, and the structure 1
0 is constructed in a tube shape with X-direction frames 13, 13 and Y-direction frames 14, 14, which are each composed of columns 11... and beams 12..., and this entire structure 10 resists seismic force. It is made to be.

In this structure 10, the beam 1
2... is spanned between each pillar 11... at the floor position of this building at an interval of two layers of this building, and the beam 12... is spanned between each of the adjacent columns 11... They are separated from each other by one layer of the building. In other words, the beams 12 on each floor are not continuous with each other and span every span, and the beams on the floors directly above and directly below the span where the beams 12 are installed are omitted. There is.

Moreover, these beams 12... are shown in FIGS. 2 and 3.
As shown in the figure, the floors 15 are supported by the lower ends of the reverse beams, that is, the beams 12 (FL in FIGS. 2 and 3 indicates the position of the top surface of each floor). In addition, small beams 16 are provided in spans where beams 12 are not provided. This beam 16
. . . may have a very small cross section that can support the floor 15 . . . or may be omitted if unnecessary in terms of design.

In addition, in this building, as shown in Figure 3,
A balcony is provided with a floor 15 protruding from the outside of the pillar 11.

This structure 10 supports the vertical load with about half the number of beams 12 compared to the conventional structure, and forms a tube frame together with the columns 11 as described above to bear the earthquake force as a whole. Because of this, the beam dimensions of the beams 12 are larger than those of conventional general frame structures.
The beams 2 are also larger than the beams 2 in the conventional tube frame structure 5 shown in FIG. 5, thereby ensuring sufficient rigidity.

In the structure 10 having the above configuration, when compared with the conventional structure 5 in which the beams 2 are continuous in each span,
It is possible to reduce the amount of steel while ensuring the same or higher rigidity and strength.

This will be explained by showing respective design examples. First, the beam 2 in the conventional structure 5 is H
The dimensions of each part are 550mm (beam size) x 300mm (width) with shaped steel.
x 16 mm (web thickness) x 25 mm (flange thickness), the amount of steel in this beam 2 is 180 kg/m per 1 m of the total span length, and the value of the moment of inertia, which represents the rigidity of the beam 2, is I=1.20×10 ⁵ (cm ⁴ ), and the value of the section modulus representing the yield strength is Z=4367 (cm ³ ).

On the other hand, the beams 12 in the structure 10 of this embodiment are made of H-beam steel with dimensions of 900 mm at each part so that one beam can have the strength of two of the beams 2.
×300mm×16mm×28mm, the amount of steel frame is
238Kg/m, second moment of area is I=4.0×10 ⁵
(cm ⁴ ), the section modulus is Z = 8880 (cm ³ ), and Z is almost the same (that is, the same proof strength) for the two conventional beams 2 (H-550 x 300 x 16 x 25), I is 70%
(improved rigidity), and the amount of steel frame decreased by 34% (cost reduction).

That is, in this structure 10, although the individual beams 12 are larger than the conventional beams 2,
Since the required number is about half, structure 1
0 Overall, the amount of steel can be reduced. As a result, the rigidity and yield strength do not decrease, and as is clear from the above values of I and Z, they can be increased to the same level or on the contrary.

In addition, in this structure 10, the transmission of stress to the frame perpendicular to the applied direction of seismic force is
This is more effective than the conventional structure 5. That is, axial force is generated in each column 11 of the frame perpendicular to the direction of force application in a distribution state as shown in Fig. 4A, but this distribution is different from the conventional case shown in Fig. 6 (broken line in the figure). ), the outer pillars are smaller and the middle pillars are larger. This indicates that the stress is effectively transmitted to the middle column, reducing the burden on the outer columns, and the stress is borne by the entire frame.
In addition, the shear force distribution of this frame is as shown in Figure 4 (b), which also reduces the stress at the middle column compared to the conventional case (indicated by the broken line in the figure), reducing the burden. The smaller outer pillars 11 are slightly larger, so that the load is almost equally distributed throughout.

Furthermore, in this structure 10, since the beams 12... are reverse beams, sufficient space under the beams can be secured even when the floor height is small, and the outer wall (not shown) has the lower end of the beam 12... An opening can be freely provided in the range up to the floor 15 of the lower floor, and a so-called sweep window that can be used for entering and exiting the balcony can be provided. Also, although it is not possible to install a sweeping window in the span where these beams 12... come out above the floor, it is possible to provide an opening between the top end of the beam 12... and the bottom end of the small beam 16..., which is also sufficient here. A large window area can be secured. Therefore, in the tube structure, the spacing between columns is small and each dwelling unit consists of two or more spans, making it possible to secure entrances and exits to balconies.
To provide a dwelling unit with excellent livability by ensuring a sufficient window area without impairing usability.

In this way, by making the beams 12... inverse beams, it can also be applied to buildings with relatively small floor heights such as apartment complexes, which was previously difficult to apply due to restrictions on openings provided in external walls. , it becomes possible to apply a tube structure.

Although one embodiment of the present invention has been described above, the present invention cannot be applied to buildings of various shapes (plan shapes and number of floors) and buildings of various uses. Further, the beams do not necessarily have to be reverse beams, but may be forward beams.

Note that the interior of the structure may be designed as appropriate, and may have no columns or beams, or may of course be provided with columns and beams at required locations. Furthermore, a tube-like structure similar to the above structure can be provided inside the structure to form a double tube structure.

"Effects of the Invention" As explained in detail above, according to the present invention, the beams are provided at the floor position between each column at two-layer intervals, and the beams provided between adjacent columns are Since the structure is shifted by one layer,
It is possible to reduce the amount of steel compared to conventional structures without reducing the strength of the building.
This has the effect of significantly reducing construction costs.

[Brief explanation of drawings]

1 to 4 are diagrams showing embodiments of the present invention. Fig. 1 is a perspective view showing the overall schematic configuration of the structure of this embodiment, Fig. 2 is a partial elevation view of the structure, Fig. 3 is a sectional view thereof, and Fig. 4 is each column of this structure. FIG. 2 is a diagram showing the state of stress distribution, of which A is a diagram showing the axial force distribution, and B is a diagram showing the shear force distribution. 5 and 6 are diagrams showing a conventional structure, in which FIG. 5 is a perspective view showing its overall schematic configuration, and FIG. 6 is a diagram showing a column axial force distribution in an orthogonal frame. 10...Structure, 11...Column, 12...Beam.

Claims (1)

[Claims] 1. A building structure constructed from a plurality of columns erected at the outer circumferential position of a multi-story building in plan view and beams spanned between the columns, which Some or all of the beams are provided between the pillars at the floor level of the building at two-story intervals, and the beams provided between the adjacent pillars are: Building structures characterized by being offset from each other by one layer of the building.