Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TOP-CHORD BEARING WOODEN JOIST AND METHOD
FIELD OF THE APPLICATION
[0001] The present application relates to wooden joists
and, more particularly, to a wooden joist used in a top-
chord bearing configuration.
BACKGROUND OF THE ART
[0002] Wooden joists are horizontal supporting members
that run from wall to wall, wall to beam, or beam to beam to
support a ceiling, roof or floor. Wooden joists have a pair
of horizontal chords, interrelated by a board in an I-joist
configuration, or by V-shaped webs, in an open-joist or
joist configuration.
[0003] When wooden joists are transversely connected to
beams, metal hangers are used to interrelate the joists to
the beams. Hangers are brackets that are secured to the
beam, and that define a U-shaped so as to support an end of
a joist. Hangers are costly items, and require a non-
negligible amount of skilled manpower to use.
[0004] Some wooden joists are used in a top-chord bearing
configuration. In this configuration, the top chord has an
extension projecting beyond the bottom chord at an end of
the joist. The extension is seated on top of a beam, when
the joist is transversely positioned on a beam. As all-
wooden joists typically use an adhesive between the chords
and the wooden webs/board, all-wooden joists are not used in
a top-chord bearing configuration. The top-chord bearing
configuration is used with open joists in which the webs are
metal, or in open joists in which metal square plates
interface the wooden webs to the chords. Both these open
joists are relatively expensive as they use numerous metal
components.
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SUMMARY OF THE APPLICATION
[0005] It is therefore an aim of the present application
to provide a novel wooden joist for use in a top-chord
bearing configuration.
[0006] It is a further aim of the present application to
a method for adapting a wooden joist to a top-chord bearing
configuration.
[0007] Therefore, in accordance with the present
application, there is provided a wooden joist comprising: a
wooden top chord; a wooden bottom chord; a main section
comprising at least one of wooden boards and wooden webs
adhesively connected to the wooden top chord and to the
wooden bottom chord to form at least one of an I-joist
subsection and an open-joist subsection along the main
section of the wooden joist; an end configuration at at
least one end of the main section, comprising: a wooden post
extending generally perpendicularly between the wooden top
chord and the wooden bottom chord and being adjacent to the
main section; a wooden diagonal web extending diagonally
from the wooden top chord to the wooden bottom chord; a
first set of metal plates in alignment on opposed sides of
the wooden joist to connect the wooden top chord to the
diagonal web; a second set of metal plates in alignment on
opposed sides of the wooden joist to connect the diagonal
web and the post to the bottom chord; a third set of metal
plates in alignment on opposed sides of the wooden joist to
connect the wooden top chord to the post; and an extension
defined by the wooden top chord extending beyond the
diagonal web at an end of the wooden joist; whereby the
wooden joist is adapted to be in a top-chord bearing
relation with a beam by the extension being on top of the
beam.
[0008] Further in accordance with the present
application, there is provided a wooden joist comprising: a
wooden top chord; a wooden bottom chord; a main section
comprising at least one of wooden boards and wooden webs
adhesively connected to the wooden top chord and to the
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wooden bottom chord to form at least one of an I-joist
subsection and an open-joist subsection along the main
section of the wooden joist; an end configuration at at
least one end of the main section, comprising: a first
wooden post extending generally perpendicularly between the
wooden top chord and the wooden bottom chord and being
adjacent to the main section; a wooden diagonal web
extending diagonally from the wooden top chord to the wooden
bottom chord; a wooden second post extending generally
perpendicularly from the wooden top chord to the wooden
bottom chord at an end of the bottom chord; a first set of
metal plates in alignment on opposed sides of the wooden
joist to connect the wooden top chord to the diagonal web
and to the first post; a second set of metal plates in
alignment on opposed sides of the wooden joist to connect
the diagonal web and the second post to the bottom chord; a
third set of metal plates in alignment on opposed sides of
the wooden joist to connect the wooden top chord to the
second post; a fourth set of metal plates in alignment on
opposed sides of the wooden joist to connect the wooden
bottom chord to the first post; and an extension defined by
the wooden top chord extending beyond the second post at an
end of the wooden joist; whereby the wooden joist is adapted
to be in a top-chord bearing relation with a beam by the
extension being on top of the beam.
[0009] Still further in accordance with the present
application, there is provided a wooden joist comprising: a
wooden top chord; a wooden bottom chord; a main section
comprising at least wooden boards adhesively connected to
the wooden top chord and to the wooden bottom chord to form
at least an I-joist subsection along the main section of the
wooden joist; an end configuration at at least one end of
the main section, comprising: a wooden post extending
generally perpendicularly between the wooden top chord and
the wooden bottom chord and being adjacent to the I-joist
subsection of the main section; a first set of metal plates
in alignment on opposed sides of the wooden joist to connect
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the wooden top chord to the wooden post; a second set of
metal plates in alignment on opposed sides of the wooden
joist to connect the post to the bottom chord; and an
extension defined by the wooden top chord extending beyond
the post at an end of the wooden joist; whereby the wooden
joist is adapted to be in a top-chord bearing relation with
a beam by the extension being on top of the beam.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Fig. 1 is a schematic view of a joist-end
configuration in accordance with a first embodiment of the
present disclosure, the first joist-end configuration being
adjacent to an open-joist section of a joist;
[0011] Fig. 2 is a schematic view of the joist-end
configuration of Fig. 1, as adjacent to an I-joist section
of a joist;
[0012] Fig. 3 is a schematic view of the joist-end
configuration of Fig. 1, with a support block;
[0013] Fig. 4 is a schematic view of the joist-end
configuration of Fig. 3, as adjacent to an I-joist section
of a joist;
[0014] Fig. 5 is a schematic view of the joist-end
configuration of Fig. 3, with a secondary post;
[0015] Fig. 6 is a schematic view of the joist-end
configuration of Fig. 1, as adjacent to an I-joist section
of a joist;
[0016] Fig. 7 is a schematic view of the joist-end
configuration of Fig. 5, with a support block;
[0017] Fig. 8 is a schematic view of the joist-end
configuration of Fig. 7, as adjacent to an I-joist section
of a joist;
[0018] Fig. 9 is a schematic view of the first joist-end
configuration of Fig. 1, with a secondary top chord;
[0019] Fig. 10 is a schematic view of the joist-end
configuration of Fig. 9, as adjacent to an I-joist section
of a joist;
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[0020] Fig. 11 is a schematic view of the joist-end
configuration of Fig. 9, with a longer secondary top chord;
[0021] Fig. 12 is a schematic view of a joist-end
configuration in accordance with another embodiment of the
present disclosure, the joist-end configuration being
adjacent to an open-joist section of a joist;
[0022] Fig. 13 is a schematic view of the joist-end
configuration of Fig. 12, as adjacent to an I-joist section
of a joist;
[0023] Fig. 14 is a schematic view of the joist-end
configuration of Fig. 12, with a support block;
[0024] Fig. 15 is a schematic view of the joist-end
configuration of Fig. 14, as adjacent to an I-joist section
of a joist;
[0025] Fig. 16 is a schematic view of a joist-end
configuration in accordance with yet another embodiment of
the present disclosure, the joist-end configuration being
adjacent to an I-joist section of a joist;
[0026] Fig. 17 is a longitudinal view of a joist with the
joist-end configuration of Fig. 2 at one end;
[0027] Fig. 18 is a longitudinal view of a joist with the
joist-end configuration of Fig. 7 at one end;
[0028] Fig. 19 is a longitudinal view of an I-joist
section with the joist-end configurations of Fig. 2 at both
ends; and
[0029] Fig. 20 is a longitudinal view of an I-joist
section with the joist-end configuration of Fig. 10 at one
end.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0030] Referring to the drawings, and more particularly
to Figs. 1 to 19, joist-end configurations are illustrated
at the ends of joists comprising a top chord 1, a bottom
chord 2, and a main section of joist comprising at least one
of an open-joist subsection of wooden webs 3 (Fig. 1), and
an I-joist subsection of wooden boards 4 (Fig. 2).
Reference numerals 1 to 4 are used hereinafter to refer to
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these components. The joists of Figs. 1-19 are said to be
all-wooden, in that the top chord 1, the bottom chord 2, the
open-joist subsection of wooden webs 3 and the I-joist
subsection of wooden boards 4 are interconnected by an
adhesive, and complementary joints (e.g., finger joints).
[0031] Referring to Fig. 1, a first joist-end
configuration is illustrated at 10, at the end of an open-
joist section of a joist. The first joist-end configuration
has a diagonal 11 (a.k.a., an end web) and a post 12
(i.e., column) between the top chord 1 and the bottom chord
2. The diagonal 11 is connected to the top chord 1 by a
first set 13 of metal plates (one shown, but with one on
each side of the top chord 1). The diagonal 11 and the post
12 intersect at the bottom chord 2, with a second set 14 of
metal plates (one shown) connecting the bottom chord 2, the
diagonal 11 and a bottom end of the post 12. The diagonal
11 has a double-cut end so as to have a first surface in
planar contact with the bottom chord 12, and a second
surface in planar contact with the post 12. A top end of
the post 12 is connected to the top chord 1 by a third set
of metal plates. For clarity of the illustrations, the
sets of metal plates are shown as being transparent
throughout Figs. 1 to 10.
[0032] The metal plates of the sets 13, 14 and 15 and all
other sets described hereinafter are of the type having
serrated surfaces that will grip into the wooden components
when pressed against them. The metal plates (which may be a
plurality of sub-plates) are paired up such that metal
plates are in alignment on opposed sides of the chords 1 and
2. Moreover, the sets 13, 14 and 15 may have any suitable
dimension. Accordingly, the various wooden components of
the joist-end configurations described above and
hereinafter, such as the diagonal 11 and the post 12, have
the same width as the top chord 1 and the bottom chord 2,
for the metal plates to form a planar joint when connecting
such pieces. It is not required to use adhesives to connect
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the wooden components with the top chord 1 and the bottom
chord 2, when metal plates are used.
[0033] In the embodiment of Fig. 1, the diagonal 11 is
connected to the top chord 1 adjacent to an end thereof,
thereby defining an extension 16 (i.e., a bearing
extension). The extension 16 is the interface of the top
chord 1 with beam A when the joist is in a top-chord bearing
relation with the beam A, as illustrated in Fig. 1.
Accordingly, by the diagonal 11 being adjacent to the
extension 16, the joist-end configuration 10 has the
diagonal 11 in tension.
[0034] Referring to Fig. 2, a joist-end configuration is
shown at 20, and is similar to the joist-end configuration
of Fig. 1, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
10 and 20 is that the joist-end configuration 20 is adjacent
to an I-joist section of the joist, as opposed to an open-
joist section for the joist-end configuration 10. The
joist-end configuration 20 therefore also has the diagonal
11 in tension.
[0035] Referring to Fig. 3, a joist-end configuration is
shown at 30, and is similar to the joist-end configuration
10 of Fig. 1, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
10 and 30 is that the joist-end configuration 30 has a
support block 31. The support block 31 is connected to the
top chord 1 by the first set 13 of metal plates, and
interfaces the top chord 1 to the beam A when the joist is
in the top-chord bearing relation with the beam A. The
joist-end configuration 30 advantageously has the set 13 of
metal plates above the bearing interface between the beam A
and the support block 31. This configuration increases the
capacity of the joist.
[0036] Referring to Fig. 4, a joist-end configuration is
shown at 40, and is similar to the joist-end configuration
30 of Fig. 3, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
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30 and 40 is that the joist-end configuration 40 is adjacent
to an I-joist section of the joist, as opposed to an open-
joist section for the joist-end configuration 30.
[0037] Referring to Fig. 5, a joist-end configuration is
shown at 50, and is similar to the joist-end configuration
of Fig. 1, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
10 and 50 is that the joist-end configuration 50 has a
second post 51. The second post 51 is connected to the top
chord 1 at an intersection with the diagonal 11, whereby the
top chord 1, the diagonal 11 and the second post 51 are
interconnected by the first set 13 of metal plates. The
second post 51 is connected to the bottom chord 2 by a
fourth set 52 of metal plates. Accordingly, the second post
51 has the same width as the top chord 1, the bottom chord
2, the diagonal 11 and the post 12. Because of the second
post 51, the first set 13 of metal plates have a greater
gripping surface with wooden components of the joist,
thereby increasing the capacity of the joist.
[0038] Referring to Fig. 6, a joist-end configuration is
shown at 60, and is similar to the joist-end configuration
50 of Fig. 5, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
50 and 60 is that the joist-end configuration 60 is adjacent
to an I-joist section of the joist, as opposed to an open-
joist section for the joist-end configuration 50.
[0039] Referring to Fig. 7, a joist-end configuration is
shown at 70 is similar to the joint-end configurations 30
(Fig. 3) and 50 (Fig. 5), whereby like elements will bear
like reference numerals. Essentially, the joist-end
configuration 70 has the support block 31 and the second
post 51, as well as the appropriate sets of metal plates to
interconnect these wooden components to a remainder of the
joist. The joist-end configuration 70 therefore benefits in
terms of capacity from the presence of the support block 31
and of the second post 51.
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[0040] Referring to Fig. 8, a joist-end configuration is
shown at 80, and is similar to the joist-end configuration
70 of Fig. 7, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
70 and 80 is that the joist-end configuration 80 is adjacent
to an I-joist section of the joist, as opposed to an open-
joist section for the joist-end configuration 70.
[0041] Referring to Fig. 9, a joist-end configuration is
shown at 90, and is similar to the joist-end configuration
of Fig. 1, whereby like elements will bear like reference
numerals. The joist-end configuration 90 has a secondary
top chord 91. The secondary top chord 91 is connected
against an undersurface of the top chord 1, from extends
along the joist from the post 12 to the extension 16. The
sets 13 of metal plates connect the top chord 1, the
diagonal 11 and the secondary top chord 91. The sets 15 of
metal plates connect the top chord 1, the top end of the
post 12 and the secondary top chord 91. The secondary top
chord 91 lies on the beam A when the joist is in top-chord
bearing relation with the beam A. The addition of the
secondary top chord 91 increases the capacity of the joist.
[0042] Referring to Fig. 10, a joist-end configuration is
shown at 100 , and is similar to the joist-end configuration
90 of Fig. 9, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
90 and 100 is that the joist-end configuration 100 is
adjacent to an I-joist section of the joist, as opposed to
an open-joist section for the joist-end configuration 90.
[0043] Referring to Fig. 11, a joist-end configuration is
shown at 110, and is similar to the joist-end configuration
90 of Fig. 9, whereby like elements will bear like reference
numerals. However, in the joist-end configuration 110, the
portion of the top chord 1 extending from the post 12 to the
extension 16 is longer than that of the joist-end
configuration 90 of Fig. 1. Accordingly, the diagonal 11
and secondary top chord 111 are longer than the joist-end
configurations of Figs. 1 to 10. It is observed that the
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sets 14 and 15 of metal plates do not connect the post 12 to
the top chord 1 and to the bottom chord 2, as chords 1 and 2
are wider than the post 12. Although not illustrated, the
joist-end configuration 110 may be used adjacent to I-joist
sections.
[0044] In Figs. 1 to 12, the diagonal 11 connects to the
top chord 1 adjacent to the beam A, and connects to the
bottom chord 2 adjacent to the post 12.
[0045] Referring to Figs. 12 to 15, alternatives
embodiments are shown, in which the diagonal is oriented
differently than in Figs. 1 to 11, and is therefore in
compression. Referring to Fig. 12, a joist-end
configuration 120 is similar to the joist-end configuration
of Fig. 1, whereby like elements will bear like reference
numerals. In the joist-end configuration 120, diagonal 11'
connects to the top chord 1 adjacent to the post 12, by the
set 13 of metal plates interconnecting the three components.
The secondary post 51 is connected to the bottom chord 2 by
the set 14 of metal plates, and is connected to the top
chord 1 by a fourth set 121 of metal plates. The post 12 is
connected to the bottom chord 2 by set 15' of metal plates.
Because of the orientation of the diagonal 11', the joist-
end configuration 120 has smaller metal plates than for a
different orientation of diagonal, thereby representing
lesser costs.
[0046] Referring to Fig. 13, a joist-end configuration is
shown at 130, and is similar to the joist-end configuration
120 of Fig. 12, whereby like elements will bear like
reference numerals. A difference between the joist-end
configurations 120 and 130 is that the joist-end
configuration 130 is adjacent to an I-joist section of the
joist, as opposed to an open-joist section for the joist-end
configuration 120.
[0047] Referring to Fig. 14, a joist-end configuration
140 is similar to the joist-end configuration 120 of
Fig. 12, whereby like elements will bear like reference
numerals. A difference between the joist-end configurations
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120 and 140 is the use of the support block 31 has interface
between the beam A and the top chord 1. The joist-end
configuration 140 advantageously has the fourth set 121 of
metal plates above the bearing interface between the beam A
and the support block 31. This configuration increases the
capacity of the joist.
[0048] Referring to Fig. 15, a joist-end configuration is
shown at 150, and is similar to the joist-end configuration
140 of Fig. 14, whereby like elements will bear like
reference numerals. A difference between the joist-end
configurations 140 and 150 is that the joist-end
configuration 150 is adjacent to an I-joist section of the
joist, as opposed to an open-joist section for the joist-end
configuration 140.
[0049] It is pointed out that the bottom chord 2, the
diagonals 11/11' the vertical posts 12 and the second posts
51 may all have a secondary twin member, as the top chord 1
does with the secondary top chord 91 (in Fig. 9). Secondary
twin members would increase the capacity of the joist.
[0050] Referring to Fig. 16, another joist-end
configuration is illustrated at 160, with reference to
reference numerals used previously for similar elements of
the other joist-end configurations. In the joist-end
configuration 160, there is no diagonal, but rather a single
vertical post 12 connected to the bottom chord 2 by a set
161 of metal plates.
[0051] Now that a plurality of the joist-end
configurations are described, different types of joists
using such configurations are shown. Although the addition
of elements increase the structural integrity of the joists,
some applications are exposed to lesser loads in which
simple configurations such as the joist-end configuration 10
of Fig. 1 or the joist-end configuration 160 of Fig. 16 are
suitable and cost-efficient.
[0052] In Fig. 17, a joist 170 has the joist-end
configuration 10 (amongst all other possibilities) in top-
chord bearing relation with the beam A, whereas another end
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is in a bottom-chord bearing relation with beam B.
Adjustments to the length of the joist 170 are made by
removing a given length of the wooden panels 4 of the I-
joist subsection, to then add the various elements of the
configuration 10. This is typically done off-site.
[0053] Referring to Fig. 18, the joist 180 has the joist-
end configuration 70 (amongst all other possibilities) in
top-chord bearing relation with beam A. As the joist-end
configuration 70 is adjacent to an open-joist subsection, a
longitudinal adjustment of the joist 180 may be done on-site
by removing an exceeding length of the I-joist subsection.
[0054] It is pointed out that the joists and joist-end
configurations described for Figs. 1-16 may be used at both
ends of a joist, for the joist to be in top-chord bearing
relation at both ends. As an example thereof, Fig. 19
illustrates a joist 190 having a set of the joist-end
configurations 20 supported by beams A. Any other suitable
combination of joist-end configurations is considered.
[0055] Referring to Fig. 20, joist 200 has the joist-end
configuration 100 in top-chord bearing relation with beam A.
The joist 200 is an I-joist that is in a bottom-chord
bearing relation with beam B at the other end. Accordingly,
a portion of the I-joist section may be removed prior to
installation, for the joist 200 to have a selected length.
Although not illustrated, it is pointed out that both ends
of the joist 200 may each have the joist-end configuration
100.
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