JP2014066087A - Building structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance economical efficiency by achieving rational stress sharing, in a frame including a plurality of span parts with different column spans.SOLUTION: In a building structure, adjacent columns 1 are joined together via a beam 2 by arranging a plurality of types of span parts S with different column spans L. Span arrangement is adjusted on the basis of each total bending moment value Mc that is the sum of a designed bending moment value Ma in the case of a sustained load acting on each beam 2 and a designed bending moment value Mb in the case of a seismic load. Thus, the total bending moment value Mc acting on the beam 2 for the plurality of types of span parts S is equalized.

Description

  The present invention relates to a building structure in which a plurality of types of span portions having different column spans are arranged and adjacent columns are joined by beams.

Conventionally, to secure flexibility as a building plane by forming a wide space, an example of setting a large column span has been given as an example. It can be used freely, or can be used as a divided space by inserting a partition according to the application. In addition, future layout changes will be facilitated. However, increasing the column span increases the bending moment value of the beam during long-term loading, so increasing the beam formation (or beam width or amount of reinforcing bars, etc.) to withstand large internal stresses. Is required.
As a conventional building structure of this kind, a span with a long column span (hereinafter simply referred to as “large span”) and a span with a short column span (hereinafter simply referred to as “small span”) are mixed. (For example, refer to Patent Document 1).

Japanese Patent Laying-Open No. 2011-162982 (FIG. 1)

According to the conventional building structure described above, the span length and the span arrangement of the large span portion and the small span portion are often determined from the viewpoint of the plane section of the building plane. The design of the beam cross section in each span portion is performed based on the sum of bending moment values, which is the sum of the design bending moment value during a long-term load and the design bending moment value during an earthquake load acting on each beam.
Accordingly, in the span portion where the large sum of bending moments acts, a large beam formation is set as compared with the span portion where the small sum of bending moments acts, and the beam formation differs depending on the span portion.
Further, from the viewpoint of design different from the bending moment value, the beam formation of all span portions may be aligned with the maximum beam formation.
In the case of the above-mentioned "beam formation varies depending on the span part", in order to secure a predetermined ceiling height in any part, it is necessary to determine the floor height based on the span part of the largest beam formation, Since the floor height itself becomes high, it is desired to improve the rationality in the member design.
In addition, in the above-described case, “all the beam sections of all span portions are aligned with the maximum beam structure”, beams that are excessively designed due to stress appear, and it is also desired to improve the rationality in the member design.
That is, according to the conventional building structure, there is a problem of lack of rationality in the member design in each span portion.

  Accordingly, an object of the present invention is to solve the above-mentioned problems and provide a building structure capable of achieving rational stress sharing and improving economic efficiency in a frame having a plurality of span portions having different column spans. There is a place to do.

  A first characteristic configuration of the present invention is a building structure in which a plurality of types of span portions having different column spans are arranged and adjacent columns are joined by beams, and a design at the time of long-term load acting on each beam By adjusting the span split based on the sum of the bending moment values, which is the sum of the bending moment value and the design bending moment value at the time of seismic loading, the sum of bending moments acting on the beams of the above-mentioned span parts is evenly distributed. It is in the place that has become.

  The bending moment value at the time of long-term load and the bending moment value at the time of seismic load differ depending on the span length, and the bending moment value at long-term load is proportional to the span length. While the large span portion has a large value, the small span portion has a small value. Further, since the bending moment value at the time of the earthquake load is inversely proportional to the span length, the bending moment value becomes a small value in the large span portion and a large value in the small span portion.

Therefore, the sum of the bending moment values, which are the sum of the bending moment values during the long-term load and the earthquake load, can be made uniform by adjusting the span split.
That is, in the large span portion, a bending moment value at a large long-term load and a bending moment value at a small seismic load act, whereas in the small span portion, a bending moment value at a small long-term load and Because the bending moment value at the time of a large earthquake load acts, the building where the same bending moment sum value (or almost the same value) acts on the large span portion and the small span portion by setting each span split appropriately. You can make a structure.

According to the first characteristic configuration of the present invention, the span split is adjusted based on the sum of bending moments (at the time of long-term load + at the time of earthquake load) acting on each beam of a plurality of types of span portions having different column spans. Since the sum of the bending moments acting on the beams in each span is equalized, the long-term load and earthquake load acting on the beams can be rationally distributed to the frame. Also in the section, it is possible to share the cross-sectional property of each beam.
As a result, it is possible to set a member cross section without waste, and it is possible to achieve a reduction in work period and cost reduction in building construction.

Furthermore, in the large span section, the building plane with a wide space between the pillars can be secured, while in the small span section, the rigidity of the beam end including the large span section can be maintained with high rigidity, and the entire building can be maintained. It is possible to suppress the interlayer displacement.
Note that “span split” here is not limited to the adjustment of two types of span length relationships between adjacent large span portions and small span portions, and for example, three or more types of span lengths are set. It also includes things. Furthermore, the total number of span portions with different column spans and the presence or absence of the adjacent portions are not fixed.

  A second characteristic configuration of the present invention is a building structure in which spans having different column spans are adjacent to each other and adjacent columns are joined by beams, and a design bending moment value during a long-term load acting on each beam. The sum of the bending moments acting on the beams in each adjacent span section by adjusting the length relationship between the adjacent span sections based on the sum of the respective bending moment values, which is the sum of the bending moment value and the design bending moment value at the time of seismic load It is in the place where is equalized.

  According to the second characteristic configuration of the present invention, the lengths of adjacent span portions based on the sum of bending moments (at the time of long-term load + at the time of earthquake load) acting on each beam of a plurality of types of span portions having different column spans. By adjusting the height relationship, the sum of the bending moment acting on the adjacent span beams can be equalized, so the long-term load and earthquake load acting on the beam can be rationally distributed to the frame. It is possible to share the cross-sectional properties of the beams in both the large span portion and the small span portion.

As a result, it is possible to set a member cross section without waste, and it is possible to shorten the work period and reduce the cost in building construction.
Furthermore, in the large span section, the building plane with a wide space between the pillars can be secured, while in the small span section, the rigidity of the beam end including the large span section can be maintained with high rigidity, and the entire building can be maintained. It is possible to suppress the interlayer displacement.

  The third characteristic configuration of the present invention is that the beams of the span portions having different column spans are aligned.

According to the 3rd characteristic structure of this invention, since the beam formation of the span part from which a column span differs is arranged, the same ceiling height can be ensured in each span part.
As a result, in addition to being able to improve aesthetics by flattening the ceiling, for example, when installing pipes and ducts in the space between beams on the back of the ceiling, the height is even and the usability Will improve.
Furthermore, even when the floor height is set, it is possible to set the height without waste.

  A fourth characteristic configuration of the present invention is that the member cross sections of the beams of the span portions having different column spans are made common.

According to the fourth characteristic configuration of the present invention, since the member cross sections of the beams in the span portions having different column spans are made common, the cross section design of the beam, the construction of the beam, and the joint portion with the column are provided. Design and construction can be performed efficiently without taking time and effort.
As a result, it is possible to achieve cost reduction in the entire construction including building design to construction.

  According to a fifth feature of the present invention, a plurality of types of span portions having different column spans are juxtaposed along each of a plurality of directions intersecting in plan view, and based on the sum of bending moments acting on each beam. Thus, by adjusting the respective span splits in the plurality of directions, the sum of bending moments acting on the beams of the span portions arranged along the plurality of directions is equalized.

  According to the fifth characteristic configuration of the present invention, the sum of the bending moments acting on the beams of the span portions arranged along the plurality of directions is equalized by adjusting the span split in the juxtaposed directions of the span portions. The effect of the first characteristic configuration of the present invention can be expanded not only in one direction on the building plane but also in a plurality of intersecting directions, and the whole building can be set with a lean member cross section. Therefore, the construction period can be shortened and the cost can be reduced in building construction.

  According to a sixth characteristic configuration of the present invention, the span portions having different column spans are adjacent to each other in a plurality of directions intersecting in plan view, and the plurality of directions are based on the sum of bending moments acting on each beam. By adjusting the length relationship between the adjacent span portions in each of the above, the sum of the bending moment acting on each beam of the adjacent span portions along the plurality of directions is equalized.

  According to the sixth characteristic configuration of the present invention, the sum of the bending moment acting on each beam of the span portion adjacent in the plurality of directions is equalized by adjusting the span length relationship in the adjacent direction of the span portion. From the above, it is possible to expand the operation and effect of the above-described second characteristic configuration of the present invention not only in one direction on the building plane but also in a plurality of intersecting directions. Setting is possible, and construction period shortening and cost reduction in building construction can be realized.

Building structure map Building structural framework Beam bending moment diagram Bending moment diagram of a beam in another embodiment Bending moment diagram of a beam in another embodiment Structural plan of the building of another embodiment

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2 show an embodiment of a building structure according to the present invention. Building B has a plurality of hierarchies, each of which has a large number of pillars 1 and beams erected on adjacent pillars 1. The frame is composed of 2 frames.

A span portion S is configured by a pair of adjacent columns 1 and a beam 2 installed on the pair of columns 1. Incidentally, in the embodiment, along the vertical direction (the Y direction in the drawing) in the structural plan shown in FIG. 1, a plurality of the span portions S with the column span L having a constant value are arranged in parallel. Along the horizontal direction (X direction in the figure), the large span portions S1 of the long column spans L1 and the small span portions S2 of the short column spans L2 are alternately arranged.
Further, a small beam 3 is provided in a state extending between the beams 2 arranged side by side along the longitudinal direction in the X direction.

  The pillar 1 is erected at the same position through the upper and lower layers. Therefore, the arrangement of the large span portion S1 and the small span portion S2 is also common to each layer.

  The column span L1 of the large span portion S1 and the column span L2 of the small span portion S2 are set according to the design bending moment value Ma at the long-term load acting on the end of the beam 2 of each span portion and the seismic load. The bending moment total value Mc which is the sum of the design bending moment value Mb at the time is set to be the same value (or almost the same value) (see FIG. 3).

This relationship will be described with reference to FIG.
FIG. 3A shows design bending moment values Ma1 and Ma2 under a long-term load acting on the beam 2A of the large span portion S1 and the beam 2B of the small span portion S2.
As can be seen from the figure, at the end of the beam 2A of the large span portion S1, the design bending moment value Ma1 at the time of long-term load is the design bending moment value at the end of the beam 2B of the small span portion S2 at the time of long-term load. The value is larger than Ma2.

FIG. 3B shows design bending moment values Mb1 and Mb2 at the time of an earthquake load acting on the beam 2A of the large span portion S1 and the beam 2B of the small span portion S2.
As can be seen from the figure, at the end of the beam 2A of the large span portion S1, the design bending moment value Mb1 at the time of the earthquake load is the design bending moment value at the end of the beam 2B of the small span portion S2 at the time of the earthquake load. The value is smaller than Mb2.

FIG. 3C shows bending moment sums Mc1 and Mc2 acting on the beam 2A of the large span portion S1 and the beam 2B of the small span portion S2.
As seen from the figure, the sum of bending moments Mc1 acting on the end of the beam 2A of the large span portion S1 and the sum of bending moments Mc2 acting on the end of the beam 2B of the small span portion S2 are the same (or It is almost equivalent).

  As described above, in the building structure of the present embodiment, each of the design bending moment values Ma1 and Ma2 at the time of long-term load acting on the beams 2A and 2B and the design bending moment values Mb1 and Mb2 at the time of the earthquake load are the sums. By adjusting the column spans L1 and L2 based on the bending moment total values Mc1 and Mc2, the bending moment total values Mc1 and Mc2 acting on the beams 2A and 2B of the plurality of types of span portions S1 and S2 are equalized. .

  Therefore, both the beam 2A of the large span portion S1 and the beam 2B of the small span portion S2 have the same beam h (see FIG. 2), beam width w (see FIG. 1), and the amount of reinforcing bars. Is formed. That is, the member cross-section is made common.

According to the building structure of the embodiment, the setting of the member cross section without waste is performed, and the construction period can be shortened and the cost can be reduced in building construction.
Furthermore, in the large span portion S1, a building plane having a wide space between the pillars 1 can be secured, while in the small span portion S2, the degree of fixation of the end of the beam 2 including the large span portion S1 is increased due to high rigidity. It can be maintained, and the interlayer displacement of the entire building B can be suppressed.

[Another embodiment]
Other embodiments will be described below.

<1> The building structure can be applied to any structural type such as a reinforced concrete structure, a steel reinforced concrete structure, and a steel structure. Moreover, the system comprised by on-site placement and the system formed by assembling a precast member may be sufficient.
In the previous embodiment, a ramen frame that does not include a seismic wall or braces has been described as an example. However, a building structure including a strength member such as a seismic wall or braces may be used. In this case, the span split may be considered based on the load of the frame structure obtained by subtracting the shearing force at the time of the earthquake borne by the strength member such as the seismic wall or brace.

<2> “Span split” is not limited to alternately arranging the large span portions S1 and the small span portions S2 as described in the previous embodiment. For example, FIG. 4 and FIG. As described above, the large span portions S1 or the small span portions S2 may be arranged so that they are adjacent to each other. As shown in the figure, equalization of the bending moment total values Mc is achieved.
Furthermore, as shown in FIG. 5, it may be arranged so as to provide a group of large span portions S1 and a group of small span portions S2.
Further, although not shown in the drawing, the column span L is not limited to two types of large and small, and may be, for example, a span split having three types of large, medium, and small, or more types.

<3> “Span split” is not limited to a plurality of types of span portions arranged along one direction in a plan view as described in the previous embodiment, but a plurality of crossing in a plan view. A plurality of types of span portions may be provided in parallel along each of the directions.
For example, as shown in FIG. 6, a plurality of types of span portions may be arranged in parallel along both the left-right direction and the up-down direction on the paper surface. According to the building structure of this embodiment, it is possible to expand the effects in the embodiments described above not only in one direction on the building plane but also in the orthogonal direction, and there is no waste as a whole building. The member cross section can be set, and the construction period can be shortened and the cost can be reduced in building construction.

<4> The beam 2 in each span portion S is not limited to the common cross-section of the members with the same beam h, beam width w, and reinforcing bar amount described in the previous embodiment. Alternatively, any or all of the beam width w and the amount of reinforcing bars may be different as long as they satisfy the cross-sectional specifications designed based on the equalized bending moment total value Mc.

  In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry. In addition, it goes without saying that the present invention can be carried out in various modes without departing from the gist of the present invention.

1 Column 2 Beam h Beam formation L Column span Ma Design bending moment value during long-term load Mb Design bending moment value during earthquake load Mc Bending moment combined value S Span

Claims (6)

A building structure in which multiple types of spans with different column spans are arranged and adjacent columns are joined together with beams,
By adjusting the span split based on the total bending moment value that is the sum of the design bending moment value under long-term load acting on each beam and the design bending moment value under seismic load, A building structure with equalized bending moments acting on beams. It is a building structure in which spans with different column spans are adjacent to each other and adjacent columns are joined with beams.
By adjusting the length relationship between adjacent spans based on the sum of the bending moments, which is the sum of the design bending moment values for long-term loads and seismic loads acting on each beam. A building structure that equalizes the sum of bending moments acting on beams in each span.   The building structure according to claim 1 or 2, wherein the beams of the span portions having different column spans are aligned.   The building structure according to claim 3, wherein member cross sections of the beams of the span portions having different column spans are made common. A plurality of types of span portions having different column spans are juxtaposed along each of a plurality of directions intersecting in plan view,
By adjusting the respective span splits in the plurality of directions based on the sum of the bending moment acting on each beam, the sum of the bending moment acting on each beam of the span portion arranged along the plurality of directions is equalized. The building structure according to claim 1. While adjoining the span portions having different column spans along each of a plurality of directions intersecting in plan view,
By adjusting the length relationship between the span portions adjacent in each of the plurality of directions based on the sum of the bending moments acting on each beam, it acts on each beam of the span portion adjacent along the plurality of directions. The building structure according to claim 2, wherein the sum of bending moments to be equalized is equalized.

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