U.S. patent application number 12/086932 was filed with the patent office on 2010-02-11 for load bearing frame.
This patent application is currently assigned to KABUSHIKI KAISHA KOBE SEIKO SHO (KOVE STEEL, LTD.). Invention is credited to Tadao Hatanaka, Nobuo Hiura, Toshikazu Karatsu, Takeshi Morii, Tomokazu Nakagawa, Takeo Suga, Tetsuo Tamada, Fumio Watanabe.
Application Number | 20100031600 12/086932 |
Document ID | / |
Family ID | 38287461 |
Filed Date | 2010-02-11 |
United States Patent
Application |
20100031600 |
Kind Code |
A1 |
Nakagawa; Tomokazu ; et
al. |
February 11, 2010 |
Load Bearing Frame
Abstract
The present invention is to provide a load bearing frame for
suppressing generation of buckling of diagonal materials and
breakage of connection parts and having high deformability. A load
bearing frame 1 has two pillar materials 2 and 3, two frame
materials 4 and 5 and four diagonal materials 6 to 9. A connection
point 41 between the pillar material 3 and the frame material 4 is
apart from a connection point 43 between the diagonal material 6
arranged on the uppermost side and the pillar material 3 by a
distance L1. A connection point 48 between the pillar material 3
and the frame material 5 is apart from a connection point 47
between the diagonal material 9 arranged on the lowermost side and
the pillar material 3 by a distance L2.
Inventors: |
Nakagawa; Tomokazu; (Hyogo,
JP) ; Hatanaka; Tadao; (Osaka, JP) ; Karatsu;
Toshikazu; (Osaka, JP) ; Hiura; Nobuo; (Osaka,
JP) ; Tamada; Tetsuo; (Hyogo, JP) ; Morii;
Takeshi; (Osaka, JP) ; Suga; Takeo; (Osaka,
JP) ; Watanabe; Fumio; (Kyoto, JP) |
Correspondence
Address: |
Juan Carlos A. Marquez;c/o Stites & Harbison PLLC
1199 North Fairfax Street, Suite 900
Alexandria
VA
22314-1437
US
|
Assignee: |
KABUSHIKI KAISHA KOBE SEIKO SHO
(KOVE STEEL, LTD.)
HYOGO
JP
|
Family ID: |
38287461 |
Appl. No.: |
12/086932 |
Filed: |
December 27, 2006 |
PCT Filed: |
December 27, 2006 |
PCT NO: |
PCT/JP2006/326154 |
371 Date: |
June 22, 2009 |
Current U.S.
Class: |
52/653.1 |
Current CPC
Class: |
E04B 1/24 20130101; E04B
2001/2496 20130101; E04B 2001/2454 20130101; E04B 2001/2415
20130101 |
Class at
Publication: |
52/653.1 |
International
Class: |
E04H 12/04 20060101
E04H012/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 17, 2006 |
JP |
2006-008217 |
Claims
1. A load bearing frame having a first pillar material, a second
pillar material, a first frame material for connecting one ends of
said first pillar material and said second pillar material
respectively, and a second frame material for connecting the other
ends of said first pillar material and said second pillar material
respectively, wherein a first diagonal material for connecting a
connection position which is other than both the ends of said first
pillar material and a position which is other than both the ends of
said second pillar material close to the one end of said second
pillar material in comparison with the connection position, and a
second diagonal material for connecting a connection position which
is other than both the ends of said first pillar material and a
position which is other than both the ends of said second pillar
material close to the other end of said second pillar material in
comparison to the connection position are provided with regard to
one or more connection position, and a connection point between
said first diagonal material arranged closest to the one end of
said second pillar material and said second pillar material is
apart from a connection point between said second pillar material
and said first frame material, and a connection point between said
first diagonal material arranged closest to the other end of said
second pillar material and said second pillar material is apart
from a connection point between said second pillar material and
said second frame material.
2. The load bearing frame according to claim 1, wherein a distance
between the connection point between said first diagonal material
arranged closest to the one end of said second pillar material and
said second pillar material and the connection point between said
second pillar material and said first frame material, and a
distance between the connection point between said first diagonal
material arranged closest to the other end of said second pillar
material and said second pillar material and the connection point
between said second pillar material and said second frame material
are distances corresponding to 5 to 20% of the entire length of
said second pillar material.
3. The load bearing frame according to claim 1, further comprising
a reinforcing material for connecting a position which is other
than both ends of said first frame material and a position which is
other than both ends of said second frame material, the reinforcing
material being jointed to said first diagonal material and said
second diagonal material.
4. The load bearing frame according to claim 1, further comprising
connection members arranged between said first and second pillar
materials and said first and second diagonal materials, the
connection members being fixed to said first and second pillar
materials at fixing positions apart from pillar corner parts of
said first and second pillar materials towards the inside.
5. The load bearing frame according to claim 4, wherein a distance
between the pillar corner parts of said first and second pillar
materials and the fixing positions are distances corresponding to
20 to 30% of width of side surfaces of said first and second pillar
materials.
6. The load bearing frame according to claim 2, further comprising
a reinforcing material for connecting a position which is other
than both ends of said first frame material and a position which is
other than both ends of said second frame material, the reinforcing
material being jointed to said first diagonal material and said
second diagonal material.
7. The load bearing frame according to claim 2, further comprising
connection members arranged between said first and second pillar
materials and said first and second diagonal materials, the
connection members being fixed to said first and second pillar
materials at fixing positions apart from pillar corner parts of
said first and second pillar materials towards the inside.
8. The load bearing frame according to claim 3, further comprising
connection members arranged between said first and second pillar
materials and said first and second diagonal materials, the
connection members being fixed to said first and second pillar
materials at fixing positions apart from pillar corner parts of
said first and second pillar materials towards the inside.
9. The load bearing frame according to claim 6, further comprising
connection members arranged between said first and second pillar
materials and said first and second diagonal materials, the
connection members being fixed to said first and second pillar
materials at fixing positions apart from pillar corner parts of
said first and second pillar materials towards the inside.
10. The load bearing frame according to claim 7, wherein a distance
between the pillar corner parts of said first and second pillar
materials and the fixing positions are distances corresponding to
20 to 30% of width of side surfaces of said first and second pillar
materials.
11. The load bearing frame according to claim 8, wherein a distance
between the pillar corner parts of said first and second pillar
materials and the fixing positions are distances corresponding to
20 to 30% of width of side surfaces of said first and second pillar
materials.
12. The load bearing frame according to claim 9, wherein a distance
between the pillar corner parts of said first and second pillar
materials and the fixing positions are distances corresponding to
20 to 30% of width of side surfaces of said first and second pillar
materials.
Description
TECHNICAL FIELD
[0001] The present invention relates to a load bearing frame used
for forming a wall surface of a building.
BACKGROUND ART
[0002] A general load bearing frame is formed in a truss structure
of a substantially rectangular shape in which both ends of two
pillar materials are respectively connected by two frame materials,
and the two pillar materials are diagonally connected by a
plurality of diagonal materials (refer to Patent Documents 1 and 2
for example). Here, in the conventional load bearing frame,
connection points between diagonal materials arranged on the
uppermost side and the lowermost side and pillar materials
correspond to corner parts of a frame. In the load bearing frame of
the above structure, force is smoothly transmitted, while in the
case where an excessive horizontal load is imposed, there is a
problem that a stress is concentrated on the diagonal materials and
connection parts so that buckling of the diagonal materials and
breakage of the connection parts are generated in an earlier stage
and thus deformability of the entire frame is small. In order to
solve the above problem, it can be thought that strength of the
diagonal materials (cross section capacity) and rigidity of the
connection parts are increased. However in the above case, although
a maximum load bearing capacity is increased, the deformability of
the entire frame (ductility) is reduced. Therefore, there is
sometimes a case where after a maximum load is obtained, the entire
frame suddenly collapses. As another method for solving the above
problem, it can also be thought that the connection parts between
the diagonal materials and the pillar materials are brought apart
in the vertical direction (refer to Patent Document 3 for example).
In the load bearing frame of the above structure, in the case where
the horizontal load is imposed, the diagonal materials are
plastically deformed in the axial direction, and the pillar
materials are also plastically deformed by bending. Therefore, the
deformability of the entire frame is improved.
Patent Document 1: Japanese Patent Laid-Open No. 2002-30745 (FIG.
1)
Patent Document 2: Japanese Patent Laid-Open No. 2004-116036 (FIG.
1)
Patent Document 3: Japanese Patent No. 2942481 (FIG. 1)
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
[0003] However, in the load bearing frame of the above structure,
in the case where the excessive horizontal load is imposed, the
pillar materials are plastically deformed by bending. Therefore,
the load bearing capacity for supporting the load in the vertical
direction is extremely lowered. Consequently, the above load
bearing frame cannot be used as a main structure of the building,
and is only arranged in the vicinity of other pillar materials for
supporting the load in the vertical direction.
[0004] A major object of the present invention is to provide a load
bearing frame for suppressing generation of buckling of diagonal
materials and breakage of connection parts and having high
deformability.
Means for Solving the Problems
[0005] A load bearing frame according to the present invention has
a first pillar material, a second pillar material, a first frame
material for connecting one ends of the first pillar material and
the second pillar material respectively, and a second frame
material for connecting the other ends of the first pillar material
and the second pillar material respectively, wherein a first
diagonal material for connecting a connection position which is
other than both the ends of the first pillar material and a
position which is other than both the ends of the second pillar
material close to the one end of the second pillar material in
comparison with the connection position, and a second diagonal
material for connecting a connection position which is other than
both the ends of the first pillar material and a position which is
other than both the ends of the second pillar material close to the
other end of the second pillar material in comparison to the
connection position are provided with regard to one or more
connection position, and a connection point between the first
diagonal material arranged closest to the one end of the second
pillar material and the second pillar material is apart from a
connection point between the second pillar material and the first
frame material, and a connection point between the first diagonal
material arranged closest to the other end of the second pillar
material and the second pillar material is apart from a connection
point between the second pillar material and the second frame
material.
[0006] Here, the connection point between the first diagonal
material and the second pillar material indicates an intersection
point between an extended line of a central axis of the first
diagonal material and a central axis of the second pillar material.
The connection point between the second pillar material and the
first frame material indicates an intersection point between a
central axis of the second pillar material and a central axis of
the first frame material. The connection point between the second
pillar material and the second frame material indicates an
intersection point between the central axis of the second pillar
material and a central axis of the second frame material.
[0007] According to the above configuration, even in the case where
a horizontal load (a load in the perpendicular direction to the
pillar material) is imposed on the load bearing frame, the
horizontal load is not directly transmitted to the diagonal
materials but indirectly transmitted through the pillar materials
between corner parts of a frame and the diagonal materials.
Therefore, generation of an excessive stress in the diagonal
materials and connection parts is suppressed. In comparison with
the conventional frame in which the connection points between the
diagonal materials and the pillar materials correspond to the
corner parts of the frame, since rigidity of the frame is reduced
so as to facilitate deformation, it is possible to prevent sudden
collapse after a maximum load is obtained. Therefore, in the
present invention, buckling of the diagonal material and breakage
of the connection parts in an earlier stage are suppressed, and an
energy absorption capacity excellent in deformability over the
entire frame is obtained.
[0008] Further, in the load bearing frame according to the present
invention, a distance between the connection point between the
first diagonal material arranged closest to the one end of the
second pillar material and the second pillar material and the
connection point between the second pillar material and the first
frame material, and a distance between the connection point between
the first diagonal material arranged closest to the other end of
the second pillar material and the second pillar material and the
connection point between the second pillar material and the second
frame material may be distances corresponding to 5 to 20% of the
entire length of the second pillar material.
[0009] According to the above configuration, it is possible to
suppress the generation of the buckling of the diagonal materials
and the breakage of the connection parts in the earlier stage, and
also to prevent a large decrease in a load bearing capacity of the
entire frame.
[0010] Further, the load bearing frame according to the present
invention may further comprise a reinforcing material for
connecting a position which is other than both ends of the first
frame material and a position which is other than both ends of the
second frame material, the reinforcing material being jointed to
the first diagonal material and the second diagonal material.
[0011] According to the above configuration, even in the case where
length of the diagonal materials is longer than height of the frame
(height of a rectangular frame) (in the case where a ratio between
width and the height of the frame is large), it is possible to
improve buckling strength of the diagonal materials. Therefore, it
is possible to improve the load bearing capacity of the entire
frame.
[0012] Further, the load bearing frame according to the present
invention may further comprise connection members arranged between
the first and second pillar materials and the first and second
diagonal materials, the connection members being fixed to the first
and second pillar materials at fixing positions apart from pillar
corner parts of the first and second pillar materials towards the
inside.
[0013] According to the above configuration, even in the case where
force in the direction of leaving apart from the pillar materials
is imposed on the diagonal materials, energy is absorbed by plastic
deformation of the connection members. Therefore, the load bearing
capacity of the entire frame is improved.
[0014] Further, in the load bearing frame according to the present
invention, a distance between the pillar corner parts of the first
and second pillar materials and the fixing positions may be
distances corresponding to 20 to 30% of width of side surfaces of
the first and second pillar materials.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 A view showing a schematic configuration of a load
bearing frame according to a first embodiment of the present
invention. FIG. 1A is a front view, FIG. 1B is a bottom view and
FIG. 1C is a side view.
[0016] FIG. 2 An enlarged view of the vicinity of a connection part
between a pillar material and a connection member.
[0017] FIG. 3 A sectional view by line III-III of FIG. 2.
[0018] FIG. 4 A view showing a deformed state of the connection
member.
[0019] FIG. 5 A view showing a schematic configuration of a load
bearing frame according to a second embodiment of the present
invention. FIG. 5A is a front view, FIG. 5B is a bottom view and
FIG. 5C is a side view.
[0020] FIG. 6 A view showing a fixing condition and a loading
condition of the frame in an evaluation test.
[0021] FIG. 7 A view showing a result of the evaluation test.
EXPLANATION OF THE REFERENCE NUMERALS
[0022] 1, 01: Load bearing frame [0023] 2, 3: Pillar material
[0024] 4, 5: Frame material [0025] 6, 7, 8, 9: Diagonal material
[0026] 10: Connection member [0027] 102, 103: Reinforcing
material
BEST MODE FOR CARRYING OUT THE INVENTION
[0028] Hereinafter, a description will be given to preferred
embodiments of the present invention with reference to drawings.
FIG. 1 is a view showing a schematic configuration of a load
bearing frame according to a first embodiment of the present
invention. FIG. 1A is a front view, FIG. 1B is a bottom view and
FIG. 1C is a side view. FIG. 2 is an enlarged view of the vicinity
of a connection part between a pillar material and a connection
member. Although FIG. 2 shows the vicinity of a connection part
between a pillar material 3 and a connection member 10, a
configuration of the vicinity of a connection part between a pillar
material 2 and the connection member 10 is the same. FIG. 3 is a
sectional view by line III-III of FIG. 2.
[0029] A load bearing frame 1 (hereinafter, referred to as the
frame 1) shown in FIG. 1 is a steel frame for a steel house. The
frame 1 has two pillar materials 2 and 3, two frame materials 4 and
5 and four diagonal materials 6 to 9. The pillar materials 2 and 3
and the frame materials 4 and 5 are quadrilateral tube members
having rectangular cross sections (refer to FIG. 2). The diagonal
materials 6 to 9 are members in an open cross sectional shape.
[0030] The two pillar materials 2 and 3 extend in the vertical
direction and are arranged in parallel to each other with a
predetermined clearance therebetween. The two frame materials 4 and
5 are horizontally arranged and connected to upper ends or lower
ends of the pillar materials 2 and 3 respectively. Therefore, an
outer shape of the frame 1 is formed in a substantially rectangular
shape by the pillar materials 2 and 3 and the frame materials 4 and
5.
[0031] The four diagonal materials 6 to 9 connect positions which
are other than the upper ends and the lower ends of the pillar
materials 2 and 3 through connection members 10. Here, the diagonal
materials 6 to 9 and the connection members 10 are jointed to each
other by spot welding, and joint positions are shown by circle
symbols in FIG. 1. The connection members 10 and the pillar
materials 2 and 3 are jointed to each other by screw fastening as
described later.
[0032] The diagonal materials 6 to 9 are arranged in order from the
upper side to the lower side. The diagonal materials 6 and 8 are
inclined so that left ends thereof are lower than right ends
thereof and arranged in parallel to each other. The diagonal
materials 7 and 9 are inclined so that right ends thereof are lower
than left ends thereof and arranged in parallel to each other.
[0033] Further in detail, the diagonal material 6 connects a
connection point 43 of the pillar material 3 apart from a
connection point 41 between the pillar material 3 and the frame
material 4 (an intersection point between a central axis of the
pillar material 3 and a center axis of the frame material 4) to the
lower side by a distance L1, and a connection point 44 of the
pillar material 2 apart from a connection point 42 between the
pillar material 2 and the frame material 4 (an intersection point
between a central axis of the pillar material 2 and the center axis
of the frame material 4) to the lower side by a distance L1+L3.
Here, a state that the diagonal material 6 and the pillar material
3 are connected at the connection point 43 for example indicates a
state that an intersection point between the central axis of the
pillar material 3 and an extended line of a central axis of the
diagonal material 6 is at the connection point 43.
[0034] The diagonal material 7 connects the connection point 44 of
the pillar material 2 apart from the connection point 42 to the
lower side by the distance L1+L3, and a connection point 45 of the
pillar material 3 apart from the connection point 41 to the lower
side by a distance L1+2.times.L3. Similarly, the diagonal material
8 connects the connection point 45 of the pillar material 3 apart
from the connection point 41 to the lower side by the distance
L1+2.times.L3, and a connection point 46 of the pillar material 2
apart from the connection point 42 to the lower side by a distance
L1+3.times.L3. The diagonal material 9 connects the connection
point 46 of the pillar material 2 apart from the connection point
42 to the lower side by the distance L1+3.times.L3, and a
connection point 47 of the pillar material 3 apart from a
connection point 48 between the pillar material 3 and the frame
material 5 (an intersection point between the central axis of the
pillar material 3 and a central axis of the frame material 5) to
the upper side by a distance L2 (corresponding to a connection
point of the pillar material 3 apart from the connection point 41
to the lower side by a distance L1+4.times.L3).
[0035] In the present embodiment, the distance L1 between the
connection point 41 between the pillar material 3 and the frame
material 4 and the connection point 43 between the diagonal
material 6 arranged on the uppermost side and the pillar material 3
is a distance corresponding to 8.8% of the entire length of the
pillar material 3. The distance L2 between the connection point 48
between the pillar material 3 and the frame material 5 and the
connection point 47 between the diagonal material 9 arranged on the
lowermost side and the pillar material 3 is a distance
corresponding to 15.8% of the entire length of the pillar material.
Here, in the case where the distances L1 and L2 are distances less
than 5% of the entire length of the pillar material 3, a stress on
the connection parts between the diagonal materials and the pillar
materials is excessive, and thus buckling of the diagonal materials
and breakage of the connection parts are generated in an earlier
stage. Meanwhile, in the case where the distances L1 and L2 exceed
20% of the entire length of the pillar material 3, force
transmitted to the diagonal materials is extremely small, and thus
a load bearing capacity of the entire frame is largely lowered.
Therefore, the distances L1 and L2 are preferably distances
corresponding to 5 to 20% of the entire length of the pillar
material 3.
[0036] As shown in FIG. 2, the connection member 10 is a member
having a U shape cross section, and eight screw holes 10a (refer to
FIG. 3) are formed on one side surface thereof. Eight screw holes
2a or 3a (refer to FIG. 3) corresponding to the eight screw holes
10a of the connection member 10 are formed at an attachment
position to the connection member 10 on one side surface of the
pillar material 2 or 3. Therefore, as shown in FIG. 3, in the
connection member 10, screws 11 are fastened in a state that the
screw holes 10a thereof correspond to the screw holes 2a of the
pillar material 2 or the screw holes 3a of the pillar material
3.
[0037] Provided that width of the one side surface of the pillar
material 2 or 3 and one side surface of the connection member 10 is
D, the connection member 10 is screwed at a position apart from
both ends thereof towards the inside by a distance C. That is, the
screw holes 2a, 3a and 10a are formed at positions apart from
pillar corner parts by the distance C. Here, the distance C between
the pillar corner part and the screw fastening position is
preferably a distance corresponding to 20 to 30% of the width D of
an inner side surface of the pillar material 2 or 3. As mentioned
above, the screw fastening of the connection member 10 at the
position apart from the pillar corner part by a predetermined
clearance is to absorb energy by plastically deforming the
connection member 10 in the case where the force in the direction
of leaving apart from the pillar material 2 or 3 (the arrow
direction of FIG. 4) is imposed on the diagonal materials as shown
in FIG. 4. In FIG. 4, the connection member 10 before plastic
deformation is shown by a broken line, and the connection member 10
after the plastic deformation is shown by a heavy line.
[0038] Next, a description will be given to a load bearing frame
according to a second embodiment of the present invention with
reference to FIG. 5. FIG. 5 is a view showing a schematic
configuration of the load bearing frame according to the second
embodiment of the present invention. FIG. 5A is a front view, FIG.
5B is a bottom view and FIG. 5C is a side view.
[0039] A load bearing frame 101 of the second embodiment
(hereinafter, referred to as the frame 101) is different from the
frame 1 of the first embodiment in terms of the point that two
reinforcing materials 102 and 102 are further provided. The other
configuration of the frame 101 is the same as the frame 1 and thus
given the same reference numerals and a detailed description
thereof will be omitted.
[0040] The two reinforcing materials 102 and 103 are plate like
members. The reinforcing material 102 is arranged on a near side
surface of the frame 101, for connecting a central part of the
frame material 4 and a central part of the frame material 5, and
jointed to central parts of the diagonal materials 6 to 9.
Similarly, the reinforcing material 103 is arranged on an opposite
side surface of the frame 101, for connecting the central part of
the frame material 4 and the central part of the frame material 5,
and jointed to the central parts of the diagonal materials 6 to
9.
[0041] Next, a description will be given to an evaluation test for
the frames 1 and 101 and a result thereof with reference to FIGS. 6
and 7. FIG. 6 is a view showing a fixing condition and a loading
condition of the frame in the evaluation test. FIG. 7 is a view
showing the result of the evaluation test and a relationship
between a shear deformation angle and a horizontal load (an
envelope of shear deformation angle-horizontal load curve). Here,
the evaluation test is performed by repeatedly imposing the
horizontal load on upper ends of the frames 1 and 101 in a state
that lower ends of the frames 1 and 101 are fixed. As a comparative
example, the same test is performed for the conventional frame in
addition to the frames 1 and 101.
[0042] In the conventional frame, the connection parts are broken
and thus the test is ended. Meanwhile, in the frame 1, the
connection parts are not broken, and as seen from the test result
in FIG. 6, deformability and a maximum load are largely increased
in comparison to the conventional frame. In the frame 1, the
diagonal materials are finally plastically buckled and the test is
ended. However, in the frame 101 to which the reinforcing materials
are added, not only the breakage of the connection parts but also
the buckling of the diagonal materials are not generated, and hence
an energy absorption capacity which is higher than the frame 1 is
obtained.
[0043] As mentioned above, in the frames 1 and 101 according to the
present embodiments, even in the case where the horizontal load is
imposed, the horizontal load is not directly transmitted to the
diagonal materials 6 to 9. The horizontal load is indirectly
transmitted through the pillar materials between the corner parts
of the frame and the diagonal materials (a part corresponding to
between the connection point 41 and the connection point 43 of the
pillar material 3, and a part corresponding to between the
connection part 47 and the connection part 48 of the pillar
material 3). Therefore, generation of the excessive stress in the
diagonal materials 6 to 9 and the connection parts is suppressed.
In comparison with the conventional frame in which the connection
parts between the diagonal materials and the pillar materials
correspond to the corner parts of the frame, since rigidity of the
frame is reduced so as to facilitate deformation, it is possible to
prevent sudden collapse after the maximum load is obtained.
Therefore, in the present invention, the buckling of the diagonal
materials 6 to 9 and the breakage of the connection parts in the
earlier stage are suppressed, and the energy absorption capacity
excellent in the deformability over the entire frame is
obtained.
[0044] The frames 1 and 101 of the present invention can achieve a
well-balanced energy absorption capacity for the entire frame not
with a structure for absorbing the energy by plastically deforming
the pillar materials by bending but by delaying the generation of
the buckling of the diagonal materials and the breakage of the
connection parts. Since the load bearing capacity against the load
in the vertical direction is not extremely lowered, it is possible
to use the frames 1 and 101 as a main structure of a building.
[0045] The distances L1 and L2 are the distances corresponding to 5
to 20% of the entire length of the pillar material 3. Therefore, it
is possible to suppress the generation of the buckling of the
diagonal materials and the breakage of the connection parts in the
earlier stage, and also to prevent a large decrease in the load
bearing capacity of the entire frame.
[0046] The frame 101 is reinforced by the reinforcing materials 102
and 103. Therefore, even in the case where the distances of the
diagonal materials 6 to 9 are longer than height of the frame
(height of a rectangular frame) (in the case where a ratio between
width and the height of the frame is large), it is possible to
improve buckling strength of the diagonal materials. Therefore, it
is possible to improve the load bearing capacity of the entire
frame.
[0047] The connection members 10 are screwed to the pillar
materials 2 and 3 at the screw fastening positions apart from the
corner parts of the pillar materials 2 and 3 towards the inside by
a predetermined clearance. Therefore, even in the case where the
force in the direction of leaving apart from the pillar materials 2
and 3 is imposed on the diagonal materials 6 to 9, the energy is
absorbed by the plastic deformation of the connection members 10.
Therefore, the load bearing capacity of the entire frame is
improved.
[0048] The description is given to the preferred embodiments of the
present invention above. However, the present invention is not
limited to the above embodiments, and various design modifications
are available within the scope of the claims. For example, although
the frames 1 and 101 have the four diagonal materials 6 to 9 in the
above embodiments, the number of the diagonal material may be
changed. The distances L1 and L2 can also be changed.
* * * * *