Note: Descriptions are shown in the official language in which they were submitted.
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1
"A FRAM11~1G SYSTEM FOR BUILDINGS"
This invention relates to a framing system for buildings. More particularly
the
invention relates to frame members, frame assemblies incorporating such frame
members and frame buildings incorporating the frame assemblies.
Many metal framing systems have been proposed in the past to take advantage of
the
accurate fabrication which is possible in metal construction. Such metal
framing
systems have the potential to simplify construction methods and to provide
accuracy
which is not readily obtained with one off brick, concrete or timber
construction.
Metal frames also have the advantage that rigid perimeter frames can be
constructed
without the need for diagonal bracing. Typically this rigidity is associated
with
welded joints between horizontal and vertical members of the frame. This is
not
particularly suited to fabrication using galvanised or coated metal frame
members.
While the desired rigidity can be achieved by bolted or screw joints, most
systems
proposed to date have not provided the desired degree of simplicity and/or
versatility
to make them a popular aiternative to one-off timber framed construction.
The applicant is aware of steel buildings which are used for housing
warehouses and
the like, which are made by the joining of steel frames. The frames have a
base
section and rising sections which rise up from both sides of this base section
forming
an open ended rectangle. Typically this frame is then treated to resist rust.
However
the attachment of horizontal members to vertical members on site is not easily
accomplished. Some form of pressing machine is required which requires heavy
machinery to be brought on to the construction site.
Alternatively the frames are welded to each other. However for welding it is
necessary for the two frames to be positioned perpendicularly to one another
and
3 0 thus welding is complicated. Further welding damages the rust prevention
treatment.
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2
Accordingly it would be advantageous if a means could be found for erecting a
steel
frame structure on a building site expeditiously and efficiently.
This invention aims to provide vertical and horizontal members of a frame
assembly
which can be attached to each other reliably and efficiently.
This invention also aims to provide a structure wherein prefabricated frame
assemblies are stood in end to end abutting relationship to form a wall and if
required, located one upon the other in a simple and efficient manner.
The panels would be located on top of each other for the provision of multi
storey
buildings or for providing relatively small wall panels which may be easily
handled
and stacked one upon the other. The panels would be placed in abutting side by
side
relationship to form a wall structure or a floor or roof structure.
According to one aspect of this invention there is provided a frame assembly
for a
building, the assembly including, a first plurality of frame members and a
second
plurality of frame members, each of said members of said first and second
plurality
defining two major surfaces and having a central channel opening to one face
of the
member and side channels on each side of the central channel opening to the
other
face of the member, wherein the first plurality of members has the base webs
of the
side channels removed at the ends thereof, and wherein the second plurality of
members has the base web of the central channel removed at the ends thereof so
that
the side channel sections extend beyond the central channel section whereby
the ends
of the first plurality of members are complementary to the ends of the second
plurality of members.
Preferably the first plurality of members is horizontally extending and the
second
plurality of members is vertically extending.
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Preferably the ends of the base webs of the side channels of the first
plurality of
members are cut away from their respective side flanges and folded back
inwardly
into the channel to form tabs which mate with the base webs of the side
channels of
a member of the second plurality of members when the two are attached, thereby
providing overlapping surfaces for attachment by the attachment means.
Preferably the ends of the base web of the central channel of the second
plurality of
members is cut away from its respective side flanges and folded back inwardly
into
the channel to form tabs which mate with the base web of the central channel
of a
member of the first plurality of members when the two are attached, thereby
providing overlapping surfaces for attachment by the attachment means.
In one particularly preferred form the inwardly folded ends of the base webs
of the
first and second plurality of members are folded substantially perpendicular
to the
remainder of the web so as to facilitate attachment of the frame members at
right
angles to one another.
Preferably the members of the first plurality of members engage the members of
the
second plurality of members such that the engaged members have overlapping
mating surfaces extending in three substantially mutually orthogonal axes.
Typically the frame assembly includes attachment means for attaching each of
the
members of the first plurality of members to the adjacent members of the
second
plurality of members.
Advantageously the overlapping mating surfaces of each of the first and second
plurality of members define aligned apertures, and the attachment means
comprises
fastening elements which are passed through said aligned apertures to securely
attach
the members to each other.
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4
Typically the frame assembly includes two vertically spaced horizontally
extending
members interconnected by two horizontally spaced vertically extending members
such that the assembly has a substantially rectangular configuration.
Optionally the horizontally extending members may be arranged with the central
channel facing outwardly relative to the rest of the frame assembly and the
vertically
extending members arranged with the central channel facing inwardly relative
to the
rest of the frame assembly.
Typically each member is made out of sheet steel and is treated to resist
corrosion
thereof and the sheet steel has a thickness of 0.8 - 1.5 mm.
According to another aspect of this invention there is provided a frame
assembly for
a building, the assembly including, a plurality of frame members each having a
1 S central channel section opening to one face of the frame member and side
channel
sections on each side of the central channel section opening to the other face
of the
frame member, wherein the base webs of the side channels~are cut away at the
end
of one frame member to form spaced side flanges which receive the projecting
side
channels of a mating frame member which terminates with its side channels
extending beyond its central channel.
The frame assembly may include any one or more of the features described above
with respect to the first aspect of the invention. For example the frame
assembly
may include attachment means for attaching said one and mating frame member to
each other.
According to yet another aspect of this invention there is provided a method
of
forming a frame member for use in a frame assembly, the method including the
step
of folding a rectangular sheet of steel into seven side by side portions, each
portion
being folded substantially perpendicularly about its line of interconnection
with the
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adjacent portion so as to form a member having a central channel facing to one
side
of the member and side channels facing to opposite sides of the member.
Typically the method includes the additional step of dividing the rectangular
sheet
5 of steel into said seven side by side portions prior to said folding step.
Advantageously the method includes the step of cutting slits in opposed ends
of the
central panel portion to form two tabs and folding the two tabs inwardly such
that
they extend substantially orthogonally inwardly relative to the remainder of
the
central panel portion.
Alternatively the method includes the step of cutting slits in opposed ends of
the
panel portions on either side of the central portion spaced one away from the
central
potion to form two tabs on each of the portions, and folding the two pairs of
tabs
inwardly such that they extend substantially orthogonally inwardly relative to
the
remainder of the portion.
Typically the method includes the step of drilling holes in a plurality of
portions
towards each end of the portions.
According to yet another aspect of this invention there is provided a frame
building
including a plurality of frame assemblies as defused above, the assemblies
being
arranged in side by side abutting relationship to form a peripheral wall.
The frame assemblies may include any one or more of the optional features
described above with respect to the first aspect of the invention.
Typically the building is a house and includes a roof which is supported on
the
peripheral wall.
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6
In addition to said frame assemblies being arranged in side by side abutting
relationship, they may also be mounted on top of each other to form two layers
of
panels in forming the peripheral wall.
Optionally the building may have an upper and a lower storey and the floor of
the
upper storey may be supported on the peripheral wall, and the roof in turn may
also
be supported on the peripheral wall.
Preferably the frame building includes reinforcing posts positioned between
adjacent
abutting frame assemblies.
The support posts may be made of wood and the posts may be received within
communicating side channels of adjacent vertically extending frame members.
According to yet another aspect of this invention there is provided a steel
frame
formed from a plurality of frame members, each frame member being formed into
first to seventh band-shaped sections divided by first to sixth bend lines
which extend
parallel in one direction, and at least first, third, fifth and seventh band-
shaped
sections are formed with the same width, and so that said first, third, fifth
and
seventh band-shaped sections are perpendicular to remaining second, fourth and
sixth band-shaped sections, they are bent into a valley shape at said first,
second,
fifth and sixth bend lines, and into a mountain shape at the remaining third
and fourth
bend lines, forming a section with alternate open-ended rectangle-shaped
depression
sections and protruding sections.
Preferably a notch section is formed along third and fourth bend lines at both
ends
in a longitudinal direction of the fourth band-shaped section on the main body
of the
frame, and a bend section is formed on the end of said fourth band-shaped
section
between both notch sections with the length of this notch being the same as
the width
of said fourth band-shaped section, and this bend section is bent
perpendicularly
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downward with respect to said fourth band-shaped section, thereby fornling an
open-
ended rectangle-shaped cut out section surrounded by said bend section and
third
and fifth band-shaped sections.
Alternatively a notch section is formed at both ends in a longitudinal
direction of
second band shaped section of the main body of the frame along first and
second
bend lines, and with the length of this notch section being substantially the
same as
the width of said second band shaped section, a bend section is formed at the
end of
said second band-shaped section of both notch sections, and a further notch
section
is formed along fifth and sixth bend lines at both ends in the longitudinal
direction
of the sixth band-shaped section of said main body of the frame, and with the
length
of this notch section substantially the same as the width of said sixth band-
shaped
section, a bend section is formed on the ends of said sixth band-shaped
section
between both notch sections, and both said bend sections are bent
substantially
perpendicularly upwards with respect to second and sixth band-shaped sections
respectively, thereby forming an open ended rectangle shaped cut out section
which
is surrounded by said bend section and first and third band-shaped sections
and an
open ended rectangle shaped cut out section surrounded by said bend section
and
fifth and seventh band-shaped sections.
The invention extends to a steel frame structure including first and second
frames
with sections having alternating open endedrectangle shaped depression
sections and
protruding sections, said first frame notch sections being formed along third
and
fourth bend Iines on both ends in a longitudinal direction of fourth band-
shaped
section on the main body of the frame and the length of this notch section
being
substantially the same as the width of the fourth band-shaped section, a bend
section
being formed on the end of said fourth band-shaped section between both notch
sections, this bend section being bent downwards perpendicularly with respect
to
said fourth band-shaped section, thereby foaming an open ended rectangle
shaped cut
out section surrounded by said bend section and third and fifth band-shaped
sections,
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8
and on said second frame notch sections being formed along first and second
bend
lines on both ends in a longitudinal direction of second band shaped section
of main
body of frame, and with the length of this notch section the same as the width
of the
second band-shaped section, a bend section is formed on the ends of said
second
band shaped section between both notch sections, and notch sections being
formed
along fifth and sixth bend lines on both ends on a longitudinal direction of
the sixth
band shaped section of said main body of the frame, and with the length of
this notch
section the same as the width of the sixth band shaped section, a bend section
being
formed on the end of the sixth band shaped section between both notch
sections, and
both said bend sections being bent perpendicularly upwards with respect to
second
and sixth band-shaped sections respectively, thereby forming an open ended
rectangle shaped cut out section surrounded by said bend section and first and
third
band-shaped sections, and an open ended rectangle shaped cut out section
surrounded by said bend section and fifth and seventh band shaped sections
respectively, and at least second and sixth band-shaped section of the second
frame
is at least slightly wider than the second and sixth band shaped sections of
the first
frame, and at least the fourth band shaped section of the second frame is at
least
slightly narrower than the fourth band-shaped section of the first frame.
Preferably the frame structure includes two first frames provided in parallel
at a
prescribed interval and at the joining position on the top edge of each of
these first
frames and the joining position on the lower edge, two second frames are
provided
extending perpendicularly with respect to the first frame and in addition to
mating
the protruding section formed by the third to fifth band-shaped sections ofthe
second
frame and the cut out section at the end of the first frame and the
protrusions foamed
by the first to third band-shaped sections and fifth to seventh band-shaped
sections
of the first frame are mated to the cut out section of the second frame
wherein the
overlapping parts of the first and second frames axe joined together.
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It is also preferred that the base web of the central channel section be cut
away from
its respective side flanges to form the protruding side channel sections and
that this
cut away base web section be folded into the central channel section so that
it
overlaps the base web of the complementary section, again forming further
mating
surfaces which may be bolted or screwed together.
Alternatively the inwardly folded web sections may be folded through an acute
or
obtuse angle to provide an angled connection between the joined frame members.
Preferably the mating surfaces at the join are predrilled for accurate bolting
together
of the components.
In the preferred form the bolted connection includes bolts extending through
three
mutually orthogonal axes including, bolts having their shanks disposed in a
horizontal or vertical plane and extending about transverse and longitudinal
axes and
a further bolt having its shank axis intersecting that horizontal or vertical
plane so as
to provide a secure joint between the frame members capable of transmitting
bending
moments through the joint.
Preferably the frame sections are roll formed or folded fi~om steel sheet but
they
could be formed of other materials and by other methods such as by extrusion.
It is
also preferred that the horizontal frame members of rectangular frames be
arranged
with the central channel opening to the outside of frame and that the vertical
frame
members be arranged with the side channel sections opening outwardly of the
frame.
With this arrangement, lower frame sections may be located on a central common
rail which fits snugly within the open channel section of these frame members
and
providing continuous alignment along a wall. Similarly, upper frame sections
may
support a continuous top plate or top plate section spanning the joints
between frame
sections. The vertical frame members of adjoining frames may be coupled to one
another with one or more members nested within the box sections formed by the
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opposed mating side channel sections of respective frames. Of course if
desired the
frames may be located with the side channel sections opening outwardly of the
frame
as the horizontal frame members.
5 In order that this invention be more readily understood and put into
practical effect,
reference will now be made to the accompanying drawings which illustrate a
prefewed embodiment of this invention, and wherein:-
FIG. 1 illustrates the developed blank for a frame member according to this
10 invention;
FIG. 2 illustrates the cross-sectional configuration of the formed frame
member;
FIG. 3 is a perspective view of the formed frame member;
FIG. 4(a) illustrated the developed blank with cuts for forming the frame
member with an end termination as illustrated in Figs. 4(b) and 4(c);
FIG. 5 is an enlarged perspective view of the frame member of FIG. 4;
FIG. 6(a) illustrated the developed blank with cuts for forming the frame
member with an end termination as illustrated ill Figs. 6(b) and 6(c);
FIG. 7 is an enlarged perspective view of the frame member of FIG. 6;
FIG. 8 is a perspective view illustrating the joining of complementary frame
members;
FIG. 9 provides several views including a perspective view and opposite end
views of the finished joint between complementary frame members;
FIG. 10 is a side view of a rectangular frame made with frame members and
joints as previously illustrated;
FIGS. 11 and 12 illustrate the joining of adjacent frames of the type
illustrated in FIG. 10; and
FIG. 13 is perspective view of part of adjacent frame members.
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The frames 23 of this invention include rectangular frames as illustrated in
FIG. 10
and formed from four frame members 11, I2 connected together at their corners
by
bolted joints 22 as illustrated in FIGS. 8 and 9.
It will be seen that each frame members 11, 12 is substantially identical in
section,
however the vertical members 12 are foamed to fit closely within the
horizontal
members 1 I as will become apparent from the following description.
Each frame member 11, 12 has a central channel section 30, 31 opening to one
face
ofthe respective frame member and side channel sections 32, 33 adjacent
thereto and
opening to the other face of the respective frame member 1 l, 12.
As illustrated in FIGS. 1 to 7 the frame members 11, 12 are folded or roll
formed
wide right angle bends along the fold lines 2a to 2f and the blanks 1/11 for
the
I5 vertical frame members 12 are slit at 6 inwardly from each end along the
fold lines
2c and 2d in the central panel 3d to form a tab 7. When the frame members 12
are
formed to shape, the tabs 7 are folded inwardly between the adjacent side
walls 3c
and 3e as illustrated in Figs. 4(b) & 4(c).
The blanks 1/12 are slit at each end at 13 and 15 inwardly from each end along
the
fold lines 2a, 2b and 2e, Zf in the side panels 3b and 3f to form the tabs 14
and 16.
When the frame members 11 are is formed to shape, the tabs 7 are folded
inwardly
between the adjacent side walls 3a and 3c as illustrated in FIGS. 6(b) & 6(c).
The length L 1 of the tabs 7 is so formed as to provide, when folded inwardly,
an end
protrusions 9 and a central recess 8 which accommodates the central protrusion
19
of the frame member 12. The identical lengths L3 to L5 of the tabs 14 and 16
in the
member 12 are so formed as to provide, when folded inwardly, recesses 17, 18
at
opposite sides of the protruding central channel portion 19. The recesses 17,
18
accommodate end protrusions 9.
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I2
For this purpose, the width L2 of the central panel 3d of member 11 is greater
than
the width of the central panel 3d of member 12 and the widths L4 and L6 of the
side
panels 3b and 3f of member 12 are heater than the width of the side panels 3b
and
3f of member 11.
As shown ill FIG. 8, at the joining end of the member 11, the tab 7 and wall
panels
3a, 3b, 3f and 3g are formed with respective central apertures 20 and the tabs
14, 16
and at the end of the complementary member 12 and the adjoining panels 3a, 3d,
3g
are formed with apertures 21. The apertures 20 and 21 alilm when the ends of
the
members 11, 12 are overlapped in a joining relationship as illustrated in FIG.
9, and
are through bolted by self tapping bolts or screws 22 to secure the members
11, 12
rigidly together.
For this purpose it will be seen that the apertures 20, 21 are placed in
panels in which
fasteners 22 may be accessed by a shaft of a power screw driver or the like
for rapid
assembly.
The assembled rectangular frame 23 will be rigid with the joints or a
structural skin
applied thereto resisting the loads applied along the line of the wall.
However if
desired lateral bracing struts may be connected thereto by the fasteners 22 or
additional fasteners as required.
Preferably, as illustrated in FIG. 11 the frames 23 are wall height and have
continuous central channels which open outwardly for location about a
correspondingly rectangular sectioned bottom plate. A corresponding top plate
may
be used to tie the upper horizontal members 12 together and/or to provide a
connection for roof trusses and the like.
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As can be clearly seen in FIG. 11(b), the upright side channels 32 mate to
form open
box sections 25 which may hold a joining spline or carry services or the like.
The
mating wall panels 3d may be interconnected by screwing or the Like.
FIG. 13 illustrates a portion of the member I 1 of a frame assembly 23 in side
by side
abutting relationship with a member I 1 of an adjacent frame assembly 23. The
outer
channels face outwardly and thereby the outer channels of the two members 11
open
out to each other to define a verkically extending chamber or conduit 30.
A reinforcing support post 31 may be mounted on a support surface and extend
upwardly through the conduit 30. The support post 31 may typically be made of
wood although naturally other materials are also possible. A primary function
of the
support post 31 is that it maintains struchual support in the event of a fire
which
causes the steel member 11 to melt. This additional structional safety feature
is
important.
A further advantage of the reinforcing post 31 is that it preserves the
continuity of the
wall surface when viewed from the outside. This is particularly important as
adjacent members 11 are prone to pulling apart from each other as the
structure is
developed and additional assemblies 23 are added. The continuity of the wall
surface provided by the post 31 is very important to the aesthetics and
insulation
properties of the building.
For mufti-storey buildings, it will be seen from FIG. 12 that the abutting
oppositely
disposed horizontal members 12 have their side panels 3b and 3f in face to
face
overlying relationship whereby they may be screwed together at opposite sides
of the
box section 28 formed by the opposing channels 31.
The box sections 25 and 28 provide relatively massive structural members at
each
frame joint for accommodating normal applied horizontal and vertical loads
such that
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construction using these frames should proceed quickly and with minimum
further
material to provide the structural requirements of the wall.
The frames may be supplied in complete form having at least one skin bonded
and/or
screwed thereto. Typically the skin would be a particle board such as
CRAFTWOOD or a plywood panel.
Tests were carried out by the Technical Structures Laboratory of Queensland
University to compare the shuctural strength of the applicant's frame members
as illustrated in the drawings (CDS Sections) with a "C" section frame member
("C" section}. Both types of section were fabricated from one 1.0 mm 6550
Zincalume. The "C" section was formed from steel sheet approximately 194 mm
wide while the CDS section was formed from steel sheet 197 mm wide. To
simplify the testing there was no restraint other than at the ends and the
I S unavoidable restraint occasioned at the load points.
The following tests were conducted:
a) Stud Compression Test;
b} Stud Bending Test; and
c) Plate Bending Test.
Stud Compression Test
In the stud compression test, individual stud sections of 2,700 mm length were
tested under axial load. The studs were not restrained against lateral or
torsional
movement other than by the loading of the plates at each end. The load was
applied as evenly as possible.
Two "C" sections and two CDS sections were tested. The results are provided
in the table below:
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I5
Test Identification Failure Load (kN)
Sample
"C" section stud No. 10.6
1
"C" section stud No. 13.3
2
CDS section stud No. 22
1
CDS section stud No. 24.1
2
Thus the CDS section only failed at approximately twice the load of the "C"
section.
Stud Bending Test
In the stud bending test individual stud sections of 2,700 mm length were
tested
under bending load.
One "C" section and one CDS section were subjected to the test. The results
are
provided in the table below:
Test Ultimate Deflection at Load at
IdentificationLoad (kN) Ultimate Load Deflection =
Sample (mm) Span/150 (kN)
(approximate) (approximate)
"C" section 2.3 105 0.9
stud
CDS section 1.6 22 1.5
stud
The test results can reasonably be taken as indicative of the behaviour of the
sections for loads producing a deflection of span/150. As shown in the results
table, the CDS section stud carries approximately 1.5 times the load carried
by
the "C" section stud at a deflection of span divided by 150. A valid
comparison
cannot be made regarding the ultimate strength of the sections because the
modes
of failure experienced for both sections were not representative of in-service
conditions.
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Plate Bending Test
In the plate bending test, individual plate sections of 800 mm lengths were
tested
under bending load. The bending load in deflection was measured as tile plate
was incrementally loaded to failure. Because the elate cecrinnc arP "~t
symmetrical about their bend axis, tests were carried out with die plates
facing
both upwardly and downwardly. The results of the plate bending tests are shown
below:
Sample Failure Load (kN) Load at Deflection
=
span/150 (kN)
(approximate)
"C" section plate up No. 2.121 2
1
"C" section plate up No. 2.141 2
2
"C" section plate up No. 2.162 2
3
"C" section plate down 6.984 6
No. 1
"C" section plate down 6,gg4 6
No. 2
"C" section plate down 6.857 6
No. 3
CDS section plate up No. 5.264 4
1
CDS section plate up No. 5.344 4
2
CDS section plate up No. 5.367 4
3
CDS section plate down 7.197 4
No. 1
CDS section plate down 7.149 4
No. 2
CDS section plate down 6.949 4
No. 3
In this test all of the test sections except for one "C" section plate failed
in local
bearing under the point load. Therefore different results would have been
obtained if the load was applied over a larger area in order to eliminate the
local
bearing failure.
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In summary the CDS section plate with its flanges up is around 2.5 times as
strong in bending as the "C" section plate with flanges up.
The CDS section plate with flanges down is marginally stronger in bending than
the "C" section plate with flanges down. For a continuous plate as distinct
from
the simply suppolrted plate as tested, the CDS section can carry around 1.3
times
the load carried by the "C" section.
Summary
The tests indicate that a 2,700 mm long CDS section will support approximately
twice the compressive load supported by a "C" section stud.
The tests also show that a 2,700 mm long CDS section stud will support around
1.5 times the bending load supported by a "C" section stud at the
serviceability
deflection limit.
The plate bending test showed that for a continuous plate spanning G00 mm
between supports a CDS section plate will support approximately 1.3 times the
load supported by a "C" section plate and that a CDS section plate has
approximately the same stiffness as a "C" section plate.
Finally therefore the test results showed that the CDS sections performed
either
similarly or better than a "C" section manufactured from the same material and
with approximately the same amount of steel.
An advantage of the frame assembly described above is that it provides frame
members joined together which resist deviation and deformation even if a load
is
applied thereto. This enables steel buildings of appropriate strength to be
constructed
easily and efficiently. The structural features of the frame such as the box
structure
and the attachment along three mutually orthogonal axes improves frame
rigidity and
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improves the axial and torsional load bearing properties of the assembly. The
attachment of the two members is very simple and can be done quickly and
efficiently during construction by workers without special skills.
It is also possible to pass utilities such as water piping, electrical wiring
or coolant
piping for air conditioners through the hollow section of the member.
It will of course be realized that the above has been given only by way of
illustrative
example of the invention and that all such modifications and variations
thereto as
would be apparent to persons skilled in the art are deemed to fall within the
broad
scope and ambit of the invention as defined in the claims.
