U.S. patent application number 11/696122 was filed with the patent office on 2007-08-23 for engineered structural members and methods for constructing same.
This patent application is currently assigned to TAC TECHNOLOGIES, LLC. Invention is credited to Barry Carlson, Jason Underhill.
Application Number | 20070193212 11/696122 |
Document ID | / |
Family ID | 35839873 |
Filed Date | 2007-08-23 |
United States Patent
Application |
20070193212 |
Kind Code |
A1 |
Carlson; Barry ; et
al. |
August 23, 2007 |
ENGINEERED STRUCTURAL MEMBERS AND METHODS FOR CONSTRUCTING SAME
Abstract
A system and method of manufacture providing reinforced
structurally functional load-bearing members, including but not
limited to using thermoplastic materials, such as High Density
Polyethylene (HDPE), reinforced such as with an aluminum alloy or
carbon fiber core element. Among its possible uses, the present
invention has application for provision of structural support
members, such as an illustrative I-joist product having a vertical
center member preferably comprising HDPE, and top and bottom
flanges having structurally meaningful reinforcement. The center
member and flanges preferably comprising HDPE provides a relatively
hard, durable, substantially weather-resistant structure.
Inventors: |
Carlson; Barry; (Windsor,
CO) ; Underhill; Jason; (Fort Collins, CO) |
Correspondence
Address: |
SHERIDAN ROSS PC
1560 BROADWAY
SUITE 1200
DENVER
CO
80202
US
|
Assignee: |
TAC TECHNOLOGIES, LLC
11749 WCR 76
Windsor
CO
80550
|
Family ID: |
35839873 |
Appl. No.: |
11/696122 |
Filed: |
April 3, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11194973 |
Aug 2, 2005 |
7213379 |
|
|
11696122 |
Apr 3, 2007 |
|
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60598014 |
Aug 2, 2004 |
|
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60644451 |
Jan 14, 2005 |
|
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60686870 |
Jun 1, 2005 |
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Current U.S.
Class: |
52/750 |
Current CPC
Class: |
Y10T 29/49625 20150115;
E04C 2003/0439 20130101; E04C 2003/0478 20130101; E04C 2003/043
20130101; Y10T 29/49616 20150115; Y10T 29/49982 20150115; E04C
2003/0447 20130101; E04C 3/29 20130101; Y10T 29/49623 20150115;
E04C 2003/0452 20130101; E04C 2003/0465 20130101; E04C 3/30
20130101; E04C 2003/0413 20130101; E04C 2003/0469 20130101; E04C
2003/0434 20130101 |
Class at
Publication: |
052/750 |
International
Class: |
E04B 1/00 20060101
E04B001/00 |
Claims
1. A method of manufacturing a structural support member having a
rated deflection loading, comprising: preparing a structural
reinforcing member for bonded integration into a structural support
member, the structural reinforcing member comprising a plurality of
opposing arms; forming a structural support member by feeding the
structural reinforcing member into a thermoplastic extruder and
covering the structural reinforcing member with a thermoplastic,
wherein the thermoplastic is bonded to at least a portion of an
exterior surface of the structural reinforcing member.
2. The method of claim 1, further comprising cooling the
extrusion-formed structural support member wherein the bonded
thermoplastic and structural reinforcing member share the loading
of the structural support member without separating when the
structural support member is loaded to the rated deflection
loading.
3. The method of claim 1, wherein said preparing the structural
reinforcing member includes forming an aluminum alloy extrusion
with a non-uniform surface.
4. The method of claim 3, wherein said forming the aluminum alloy
with a non-uniform surface includes providing surface attributes
that improve bonding of the thermoplastic to the structural
reinforcing member.
5. The method of claim 4, wherein the providing surface attributes
includes adding at least one of a divot, aperture, ribbing,
scarified surface and texturing to the surface of the structural
support member.
6. The method of claim 1, wherein said preparing the structural
reinforcing member further includes extruding the structural
reinforcing member and adjusting its temperature by cooling.
7. The method of claim 1, wherein said structural reinforcing
member comprises at least one of a metal alloy, aluminum, aluminum
alloy, and carbon fiber.
8. The method of claim 1, wherein said plurality of arms comprises
at least four arms.
9. The method of claim 8, wherein a bisector of an angle between a
first arm and a second arm of the plurality of arms is
substantially perpendicular to an axis of the structural support
member, and wherein the structural support member is configured for
orienting so that a compression force applied to the structural
support member is substantially parallel to said axis of the
structural support member.
10. The method of claim 1, wherein said thermoplastic comprises
HDPE.
11. The method of claim 1, wherein said structural support member
is selected from the group consisting of a beam, a post, a column,
at least a portion of an I-joist, a rim joist, and at least a
portion of a truss.
12. A method of manufacturing a structural member, comprising:
preparing a structural reinforcing member having a longitudinal
length L and a plurality of substantially hollow arms; and
extruding a resin around the structural reinforcing member along
substantially the entire longitudinal length L of the structural
reinforcing member to form the structural member.
13. The method of claim 12, wherein said preparing the structural
reinforcing member includes forming an aluminum alloy extrusion
with a non-uniform surface.
14. The method of claim 13, wherein said forming an aluminum alloy
includes providing surface attributes that improve bonding of the
resin to the structural reinforcing member.
15. The method of claim 14, wherein the providing surface
attributes includes adding at least one of a divot, aperture,
ribbing, scarified surface and texturing to a surface of the
structural member.
16. The method of claim 12, wherein said preparing the structural
reinforcing member further includes extruding the structural
reinforcing member and adjusting its temperature by cooling.
17. The method of claim 12, wherein said structural reinforcing
member comprises at least one of a metal alloy, aluminum, aluminum
alloy, and carbon fiber.
18. The method of claim 12, wherein said plurality of arms
comprises at least four arms including a first arm substantially
opposite a third arm, and a second arm substantially opposite a
fourth arm.
19. The method of claim 18, wherein a bisector of an angle between
the first arm and the second arm is substantially perpendicular to
an axis of the structural member, and wherein the structural member
is configured for orienting so that a compression force applied to
the structural member is substantially parallel to the axis of the
structural member.
20. The method of claim 12, wherein said resin comprises HDPE.
21. The method of claim 12, wherein said structural member is
selected from the group consisting of a beam, a post, a column, at
least a portion of an I-joist, a rim joist, and at least a portion
of a truss.
22. A method of forming a structural member adapted for use in a
load-bearing assembly, comprising: preparing a structural
reinforcing member from a first material having a longitudinal
length L and a plurality of arms extending outwardly therefrom;
modifying the structural reinforcing member including adding at
least one of a divot, aperture, ribbing, scarified surface and
texturing to a surface of the structural reinforcing member; and
extruding a second material around the longitudinal length L of the
structural reinforcing member and said plurality of arms to form a
structural member; wherein the structural member is configured for
use in construction of the load-bearing assembly.
23. The method of claim 22, wherein the second material is bonded
to at least a portion of the surface of the structural reinforcing
member.
24. The method of claim 22, wherein said preparing the structural
reinforcing member includes forming an aluminum alloy
extrusion.
25. The method of claim 22, wherein said preparing the structural
reinforcing member further includes extruding the structural
reinforcing member and adjusting its temperature by cooling.
26. The method of claim 22, wherein said first material comprises
at least one of a metal alloy, aluminum, aluminum alloy, and carbon
fiber.
27. The method of claim 22, wherein said plurality of arms
comprises at least four arms including a first arm substantially
opposite a third arm, and a second arm substantially opposite a
fourth arm.
28. The method of claim 27, wherein a bisector of an angle between
the first arm and the second arm is substantially perpendicular to
an axis of the structural member, and wherein the structural member
is configured for orienting so that a compression force applied to
the structural member is substantially parallel to the axis of the
structural member.
29. The method of claim 22, wherein said structural member is
selected from the group consisting of a beam, a post, a column, at
least a portion of an I-joist, a rim joist, and at least a portion
of a truss.
30. The method of claim 22, further comprising using the structural
member to construct the load-bearing assembly, the load bearing
assembly comprising at least one an indoor and outdoor support
structure.
31. The method of claim 22, wherein said second material comprises
a resin.
32. The method of claim 22, wherein said second material comprises
a thermoplastic.
33. The method of claim 22, wherein said second material comprises
HDPE.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a Divisional of U.S. application Ser.
No. 11/194,973, filed Aug. 2, 2005, which claims the benefit of
U.S. Provisional Application No. 60/598,014 filed on Aug. 2, 2004,
U.S. Provisional Application No. 60/644,451 filed on Jan. 14, 2005,
and U.S. Provisional Application No. 60/686,870 filed on Jun. 1,
2005, the entire disclosures of which are incorporated herein by
reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention is directed to construction materials,
and more particularly, to structural members, such as joists, posts
and beams, as well as methods of manufacturing the same.
BACKGROUND OF THE INVENTION
[0003] Use of engineered materials, such as wood composites and
various plastics, including recyclable thermoplastic, such as
high-density polyethylene (HDPE), is becoming increasingly popular
in the construction industry. These uses encompass various
horizontal and vertical applications that meet a range of present
decorative and/or structural construction needs.
[0004] Structural members, such as joists, beams and the like, are
currently available as wood lumber, a valuable yet limited resource
with no recycling capability, as plastic lumber, and as reinforced
or composite lumber. Composites often include wood fiber or
fiberglass in a plastic matrix, or wood composites such as I-joist
products having oriented strand board with micro-laminated top and
bottom flanges.
[0005] Wood-containing products generally are sensitive to
environmental conditions, such as the effect of moisture. Such
sensitivity must be accounted for during design, installation and
use. There are various recyclable thermoplastic products available
which are generally less sensitive to environmental conditions,
specifically to the effect of moisture, than wood and composite
products. Design benefits follow accordingly.
[0006] HDPE resins are used in a variety of blow molding,
rotational molding, and extruded applications for liquid food
containers, automotive fuel tanks, and large volume drums. HDPE is
widely known as the material of choice for recyclable milk
containers. It is also widely used for pipelines for water or other
solution distribution systems, and for liners for landfills, water,
or other solution holding ponds.
[0007] U.S. Plastic Lumber Corporation provides a fiberglass
reinforced HDPE product that is available in sizes and shapes of
standard lumber. These plastic lumber products are typically heavy
and contain fiberglass fibers that can quickly dull saw blades and
drill bits of construction equipment used to size the materials.
Other known HDPE I-joists contain hollow cores with wide flanges
that are not conducive to easy cutting-to-dimension with standard
construction tools, nor fit with standard fasteners.
[0008] Accordingly, there is a need for structural members,
including joists, beams, posts and the like, that are preferably
made of a weather-resistant recyclable material and that provide
adequate structural performance while not being too heavy or large
for practical use. In addition, there is a need for providing
reinforced structural members that provide adequate structural
performance and that can be worked with standard construction
equipment without unduly dulling cutting blades and drill bits.
There is a further need for such members to be available in either
standard and custom sizes and ratings, on demand or as needed, and
with the possibility of working the engineering tradeoff between
strength and weight in use of engineered materials, such as
HDPE.
SUMMARY OF THE INVENTION
[0009] One aspect of the present invention relates to load-bearing
systems, and methods of manufacture, that provide structurally
functional, load-bearing assemblies. Embodiments of the invention
include, but are not limited to, thermoplastic structural materials
such as HDPE in a form that is reinforced with a rigidifying
portion, such as an aluminum, aluminum alloy, or carbon fiber
core.
[0010] More specifically, novel structural members may include
various joists, beams, posts and the like, having sufficient
strength and deflection characteristics for use in structural
applications, such as framing, for decking and the like. Such
structural members are comparatively lighter in weight as compared
to currently available fiber-reinforced plastic lumber products and
are more weather-resistant compared to wood and wood-composite
products.
[0011] An illustrative I-joist product in one aspect of the present
invention defines a vertical center member preferably including
HDPE, and top and bottom flanges interconnected to the vertical
center member, also including HDPE. The HDPE provides a relatively
hard, durable, substantially weather-resistant structure. The
flanges form a system having structural vigor and enable the
HDPE-based system to provide sufficient strength, construction
flexibility, and true alignment (i.e., true to specification).
[0012] In accordance with other embodiments of the present
invention, such I-joists are provided that adequately support loads
for indoor and/or outdoor decking, flooring, and other support
systems. Webbing may be formed with or as a rigid member and may be
combined with top and bottom flanges of a relatively hard, durable,
flexible, and substantially weather-proof material. Preferred
materials include either virgin and/or recycled HDPE, surrounding a
suitable rigidizing core component, such as of an aluminum alloy.
Use of recyclable material, such as HDPE, enables cut waste to be
recycled. This recycling meets and adheres to current "Green Build"
objectives, and is environmentally proactive. Therefore, the
present invention not only achieves the design criteria required
for support, but also provides a framework suitable for re-use of
components in the future.
[0013] In various embodiments, webbing and top and bottom flanges
of I-joists are manufactured with various dimensions and
characteristics and with various materials to achieve maximum
transfer of loading with minimal to no vertical or horizontal
movement of the finished joist, as specified, while standard
construction tools can be used to cut the product to desired
dimensions.
[0014] Preferably, the load-bearing members, for example, the top
and bottom flanges of an I-joist, contain a strengthening core
material or other channel or flange reinforcing members so as to
stabilize the member and to assist in load-bearing. Thus, depending
on load requirements, either or both the top and/or bottom flanges
of an I-joist of the invention may contain one or more of various
reinforcing members, which may include aluminum or other alloys, or
other materials such as carbon fiber, and may include rods, C-
and/or M-shaped channels, channels with center slot, or other
configurations, for supplying a desired structural
reinforcement.
[0015] Load-bearing HDPE embodiments of the present invention
weather exceptionally well and do not absorb moisture. Therefore
the present invention may be freely utilized for both indoor and
outdoor support structures.
[0016] In various embodiments, vertical and/or horizontal support
members of the invention may replace wood and/or composite material
members, and may have hollow or solid cores depending upon the
application and need, while also being configurable in custom
and/or standard sizes. For example, boards, studs, posts and beams
can be provided as standard 2.times.4, 4.times.4, 6.times.6 (values
in inches) sized lumber, and joists, rim joists, and beams can be
provided as standard 2.times.8, 2.times.10, 2.times.12 sized
lumber, while engineered I-joists can be provided as standard sized
91/2 or 117/8 members with 2 1/16 flanges. It is advantageous that
such standard sizes will enable use of conventional fasteners and
other hanging hardware.
[0017] In several embodiments of the invention, structural members
are configured to meet given design specifications, which may be
custom or customary specifications. Structural configuration and
use may be anticipated accordingly during the manufacture process,
or can be adjusted before installation by selection or by adding
strengthening components.
[0018] Joists according to the invention therefore may be supplied
having specifications that enable center-to-center spacing selected
according to project needs and design specifications while still
providing substantially straight and true structural framing. These
structural members can be delivered to specification without the
need for trimming and truing as per wood lumber, and with minimal
cutting but for length adjustments, if needed. This flexibility and
reliability is uncommon to lumber products.
[0019] Another aspect of the present invention may also include an
extrusion process for extruding load members, and further provides
a dual extrusion process wherein a reinforcing member, such as an
aluminum alloy, is extruded with a specified shape, cooled,
prepared for receipt of the HPDE, and the HDPE is then extruded
around the reinforcing member, with an option of also within the
reinforcing member, and then cooled, all within a continuous
process, to form a structural assembly or member of the
invention.
[0020] In certain embodiments of the invention, the extruded
aluminum, other alloy component, or carbon fiber reinforcing member
may comprise an outer surface that includes a configuration for
enhanced bonding between itself and the HDPE. This may include
scarification of the surface, apertures in the surface, application
of bonding tape, provision of ribs or other non-flat surface
features, or the like, to provide a bonding and adhesion surface
for the HDPE. Improved bonding between the aluminum and HDPE can
improve the load bearing rating of the final product.
[0021] For at least one embodiment of the present invention having
a reinforcing member with a plurality of arms, the reinforcing
member is shaped such that with embedding of the reinforcing
member, the reinforcing member can produce a mechanical bond with
the HDPE or other surrounding material. The reinforcing member may
comprise apertures or ribbing to aid in developing a sufficient
mechanical bond between the HDPE and the reinforcing member,
thereby removing the need for adhesive bonding or scarification of
the reinforcing member, although adhesive bonding of the
reinforcing member to the HDPE, and/or scarification of the surface
of the reinforcing member are also optional.
[0022] The extrusion process can be enabled to provide various
lengths of product as desired, thereby maximizing shipping
efficiency. Typically, 60 foot lengths would optimally fill a rail
car load, while 40 foot lengths would be desired for a trailer
truck load.
[0023] Thus, in accordance with various embodiments of the present
invention, a structural joist adapted for use in a building
structure is provided, the joist comprising a substantially solid
vertical center member comprising a thermoplastic material and
having a longitudinal axis, and a top flange and a bottom flange
interconnected to said vertical center member and extending
substantially the entire length of the longitudinal axis, the top
flange and the bottom flange comprising a thermoplastic material.
In addition, the joist comprises an outer top flange interconnected
to the top flange and extending substantially an entire length of
the longitudinal axis, and an outer bottom flange interconnected to
the bottom flange and extending substantially the entire length of
the longitudinal axis. In addition, the joist comprises a metallic
non-planar channel member operatively associated with at least one
of the top flange, the bottom flange, the outer top flange, or the
outer bottom flange, the channel member extending substantially the
entire length of the longitudinal axis.
[0024] Further embodiments of the present invention also include a
joist with outer flanges, with an optional channel member. Thus, in
accordance with embodiments of the present invention, an I-joist
adapted for use in a building structure is provide, the I-joist
comprising an intermediate member having a longitudinal axis and a
top flange and a bottom flange, an outer top flange interconnected
to the top flange and extending substantially an entire length of
the longitudinal axis, and an outer bottom flange interconnected to
the bottom flange and extending substantially the entire length of
the longitudinal axis.
[0025] At least one method of manufacturing a joist having outer
flanges is provided herein, the method of manufacturing a joist
comprising providing a vertical center member having a top flange
and a bottom flange, providing an outer top flange have a
receptacle for receiving the top flange, providing an outer bottom
flange have a receptacle for receiving the bottom flange,
positioning the top flange in the receptacle of outer top flange,
and positioning the bottom flange in the receptacle of outer bottom
flange. A reinforcing channel member may also be added as part of
the method of manufacturing.
[0026] Various embodiments of the present invention may also
include joists without outer flanges. Thus, in accordance with
embodiments of the present invention, a structural joist is
provided comprising a vertical center member, a top flange and a
bottom flange connected to the vertical center member, and a
reinforcing member substantially embedded within at least one of
the top flange and the bottom flange, the reinforcing member
extending along substantially an entire length of a longitudinal
axis of the at least one of the top flange and the bottom flange,
wherein a strength of the structural joist is increased.
[0027] Other embodiments of the present invention may include a
reinforcing member used in various structures, such as post and
joists, wherein the reinforcing member includes a plurality of
arms. Thus in accordance with embodiments of the present invention,
a structural member is provided, the member comprising a
thermoplastic outer member having a longitudinal length; and at
least one reinforcing member located within the thermoplastic outer
member and extending substantially along the longitudinal length of
the thermoplastic outer member, the reinforcing member comprising a
plurality of arms.
[0028] Another embodiment of the present invention may also include
an I-joist, wherein the I-joist comprises a webbing having a
longitudinal length, with a top flange connected proximate a first
end of the webbing and a bottom flange connected proximate a second
end of the webbing, and wherein the top and bottom flanges extend
along the longitudinal length. In addition, the I-joist includes at
least one reinforcing member located within at least one of the top
flange and the bottom flange, the reinforcing member extending
substantially along the longitudinal length, and the reinforcing
member comprising a plurality of arms.
[0029] Among other embodiments of the present invention described
herein, an additional method of manufacture is provided for
manufacturing a structural support member having a rated deflection
loading. The method comprises preparing a structural reinforcing
member of at least length L for bonded integration into a
structural support member of at least length L, and forming a
structural support member preform by feeding the structural
reinforcing member into a thermoplastic extruder and extruding the
structural reinforcing member with a thermoplastic, wherein the
thermoplastic is bonded to the surface of the structural
reinforcing member along the length of at least L. In addition, the
method comprises controlled cooling of the extrusion-formed
structural support member preform wherein the thermoplastic is
bonded to the structural reinforcing member along the length of at
least L and wherein the bonded thermoplastic and structural
reinforcing member share the loading of the structural support
member without separating along the at least length L when the
structural support member is loaded to the rated deflection
loading.
[0030] Various embodiments of the present invention are set forth
in the attached figures and in the detailed description of the
invention as provided herein and as embodied by the claims. It
should be understood, however, that this Summary Of The Invention
may not contain all of the aspects and embodiments of the present
invention, is not meant to be limiting or restrictive in any
manner, and that Invention as disclosed herein is and will be
understood by those of ordinary skill in the art to encompass
obvious improvements and modifications thereto.
[0031] Additional advantages of the present invention will become
readily apparent from the following discussion, particularly when
taken together with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Various advantages and benefits of the present invention
will be better understood when considered in conjunction with the
following detailed description, making reference to the drawings
that are not necessarily to scale, wherein:
[0033] FIG. 1 is a perspective view of an illustrative I-joist in
accordance with embodiments of the present invention;
[0034] FIG. 2 is a perspective view of an upper outer flange of the
I-joist depicted in FIG. 1;
[0035] FIG. 3 is a perspective view of a lower outer flange of the
I-joist depicted in FIG. 1;
[0036] FIG. 4 is a perspective view of an I-joist in accordance
with embodiments of the present invention;
[0037] FIG. 5 is a perspective view of a channel reinforcing member
of the I-joist depicted in FIG. 4;
[0038] FIG. 6 is a perspective view of an I-joist in accordance
with embodiments of the present invention;
[0039] FIG. 7 is a perspective view of an I-joist in accordance
with embodiments of the present invention;
[0040] FIG. 8 is a perspective view of flange reinforcing members
of the I-joist depicted in FIG. 7;
[0041] FIGS. 9-11A are perspective views of I-joists in accordance
with embodiments of the present invention;
[0042] FIG. 11B is an end, side elevation view of a flange of an
I-joist having an alternate embodiment of a reinforcing member;
[0043] FIG. 12 is a perspective view of an I-joist having gusset
reinforcing members in accordance with embodiments of the present
invention;
[0044] FIG. 13 is a side elevation of an I-joist having side
vertical reinforcing members in accordance with embodiments of the
present invention;
[0045] FIG. 14 is a side elevation of an I-joist having webbing
with knockouts in accordance with embodiments of the present
invention;
[0046] FIGS. 15A-15G are perspective views of posts (or reinforced
portions of structural members) having core reinforcing members in
accordance with embodiments of the present invention;
[0047] FIGS. 16-20 show illustrative reinforcement embodiments of
the present invention, the reinforcing members suitable for use in
the flange portion of I-joists, as well as in posts;
[0048] FIG. 21 is an end, side elevation view of an I-joist in
accordance with embodiments of the present invention;
[0049] FIG. 22 is an end, side elevation view of yet another
I-joist in accordance with embodiments of the present
invention;
[0050] FIG. 23 is an end, side elevation view of a rim joist in
accordance with embodiments of the present invention;
[0051] FIG. 24 is a side elevation view a web and flange
reinforcing member in accordance with embodiments of the present
invention; and
[0052] FIG. 25 shows illustrative method of the present
invention.
DETAILED DESCRIPTION
[0053] Referring now to FIG. 1, in accordance with embodiments of
the present invention, an illustrative I-joist structural member 10
is shown. I-joist 10 includes a web member 13. Web member 13 has a
central web or webbing 14, an upper flange 18, and a lower flange
22, wherein flanges 18, 22 are interconnected by webbing 14.
[0054] As part of a typical I-joist, webbing 14 interacts as a
load-bearing member with load-bearing upper and lower flanges 18,
22. In one embodiment, web member 13 includes webbing 14, upper
flange 18 and lower flange 22 formed of a relatively hard, durable,
flexible, and substantially weather-proof material, including but
not limited to thermoplastics, such as HDPE, and/or thermoplastic
composite materials, such as HDPE with additives such as, for
example, natural or man-made fibers or particles of various
materials/compositions, including but not limited to wood particles
and/or fiberglass strands. Preferably web member 13 is
extruded.
[0055] I-joist 10 also includes an upper outer flange 26 that is
interconnected to upper flange 18 to form upper flange assembly 27
and a lower outer flange 30 that is interconnected to lower flange
22 to from lower flange assembly 29. Provision of these flange
assemblies 27, 29 increases the rigidity and load-bearing
capability of joist 10.
[0056] Typically, upper flange 18 and lower flange 22 are similar
in cross-section but they may be dissimilar according to design
specifications as needed. Likewise, typically outer upper flange 26
and outer lower flange 30 are similar in cross-section but they may
be dissimilar according to design specifications as needed.
[0057] Alternatively webbing 14, upper flange 18, and lower flange
22 are not integrally formed and may be separately manufactured and
then interconnected. For separately extruded parts, interconnection
may be by extrusion welding or the like, thus to form web member
13.
[0058] Outer flanges 26 and 30 may be formed over upper flange 18
and lower flange 22, respectively, in an integrated manufacturing
process or may be separately formed and then mated (e.g., slid) in
place and then interconnected, such as by extrusion welding or the
like. One advantage of separate components is that a single supply
can be used for both outer flanges for an I-joist with symmetrical
cross-section, which may provide some cost savings. Alternatively,
each component may be separately specified, to provide specialized
configurations, as needed, without having to interrupt regular
extrusion production runs. Such flexibility enables meeting various
architectural and custom design goals while providing some cost
savings.
[0059] Referring again to FIGS. 1-3, upper flange 18 cooperates
with its connection to webbing 14 to form a key 38. More
particularly, upper flange 18, as it extends from and in
cooperation with webbing 14, forms key 38. Accordingly, upper outer
flange 26 includes a receptacle 34 that internally substantially
corresponds in shape (i.e., cross section) to the external shape of
key 38.
[0060] Likewise, lower flange 22 and webbing 14 form a key 42, and
lower outer flange 30 includes receptacle 46 that internally
substantially corresponds in shape to the external shape of key 42.
Receptacle and key pairs 34, 38 and 46, 42, as cooperating locking
components, form locking mechanisms 39 and 43, respectively.
[0061] Locking mechanism 39 enables flanges 18 and 26 to be
intimately mated and structurally sound. Likewise, locking
mechanism 43 enables flanges 22 and 30 to be intimately mated and
structurally sound.
[0062] Outer flanges 26 and 30 preferably feature material
characteristics that generally complement the structural
characteristics of I-joist 10. In accordance with preferred
embodiments of the present invention, outer flanges 26 and 30
include HDPE material.
[0063] Webbing 14 is preferably solid, but may be a lattice,
slotted or otherwise apertured, depending on the surrounding
application environment, needs of the construction project,
load-bearing specifications, and overall construction objectives,
and may be formed of various suitable load-bearing materials, such
as HDPE, aluminum or the like.
[0064] Referring now to FIGS. 4-5, in accordance with embodiments
of the present invention, an I-joist structural member 60 is shown
that is similar to I-joist 10 described with respect to FIG. 1, and
further includes channel reinforcing members 64, 65.
[0065] By way of example and not limitation, channel reinforcing
member 64, 65 have a substantially rectangular shape with an
opening 68 along one side. The shape of each channel reinforcing
member 64, 65 allows it to be engaged or slid over upper flange 18
and lower flange 22, respectively, prior to, or in combination with
interconnecting with outer flanges 26 and 30. Preferably, channel
reinforcing members 64, 65 include a metal alloy, as for example,
an aluminum alloy, with the thickness of the sidewalls of each
channel reinforcing member being selected based on intended use and
designed loading of I-joist 60. Channel reinforcing members 64, 65
preferably extend substantially the entire longitudinal length L of
I-joist 60.
[0066] Referring now to FIG. 6, an I-joist structural member 70 in
accordance with embodiments of the present invention is shown.
I-joist 70 includes webbing 14 having an integrated upper flange 74
and lower flange 78, where flanges 74 and 78 have a relatively
larger cross-sectional area than flanges 18 and 22 of I-joist
10.
[0067] Preferred embodiments of the invention include structural
members formed with HDPE and a reinforcing member that acts as a
strengthened core for the HDPE. The HDPE is preferably without
cellular fiber content, such as wood fiber, and at least to the
extent that any such content should not seriously impact resistance
to moisture of the resulting structural member. Also preferably,
the HDPE is without mineral fiber content, such as fiberglass, to
the extent that the ability of the structural member can remain
easily cut and/or drilled without tool damage. However, unless
otherwise specified, any thermoplastic and/or thermoplastic
composite materials are collectively herein referred to as simply
"HDPE" or "thermoplastic," and it is to be understood that
reference herein to "HDPE" and "thermoplastic" includes other
possible thermoplastics other than HDPE, as well as blends,
composite/amended thermoplastic materials, and/or coated
thermoplastic members, and further includes substantially virgin or
recycled HDPE. Furthermore, other materials other than
thermoplastics are within the scope of the invention. Thus, a
structural member, such as an I-joist, that utilizes a
non-thermoplastic (non-HDPE) material to form its flanges and/or
webbing, is within the scope of the present invention.
[0068] In alternative embodiments of the invention, I-joist 70 is
formed with a structure of HDPE, wherein either the webbing 14
and/or any of the flanges, include one or more reinforcing or
strengthening members. A strengthening member 75 is indicated by
dotted detail in FIG. 6, which may include, as for example, a
fiberglass, metal, wood, or composite material.
[0069] Referring now to FIGS. 7-8, an I-joist structural member 82
in accordance with embodiments of the present invention is shown.
I-joist 82 may be understood to add elements to the basic structure
of I-joist 70, and further includes flange reinforcing members 86,
87 within flanges 74 and 78, respectively. More particularly, FIG.
8 shows an illustrative configuration which may serve for both
reinforcing members 86, 87, wherein flange reinforcing members 86,
87 are positioned in or manufactured in conjunction with formation
of flanges 74, 78, respectively.
[0070] The presence of flange reinforcing members 86, 87 improves
the structural performance of the I-joist, and allows the I-joist
to provide adequate load carrying capacity with tolerable
deflection, while maintaining a relatively small profile.
Preferably, the flange reinforcing members include a metal or metal
alloy, as for example, an aluminum alloy, with the dimensions and
thickness of the sidewalls of the flange reinforcing members being
capable of being customized and selected based on intended use of
the I-joist. The reinforcing members may also include carbon fiber.
The use of an aluminum alloy material as compared to steel as a
flange reinforcing member can enable a lighter weight I-joist and
can enable the I-joist to be cut relatively easily using standard
construction equipment. That is, an aluminum alloy provides
attractive reinforcing characteristics, while at the same time not
unduly dulling cutting blades of saws that are used to dimension to
length the I-joist. Carbon fiber provides yet a lighter weight
I-joist, but would potentially require the use of diamond-bit
blades for successful repeated cutting and dimensioning the
I-joist.
[0071] In accordance with embodiments of the present invention,
flange reinforcing members 86, 87 are encased within flanges 74,
78, wherein the material forming the flange completely surrounds
the longitudinal sides of the reinforcing member. Flange
reinforcing members preferably extend substantially the entire
longitudinal length L of the I-joist.
[0072] Flange reinforcing members may take on a variety of shapes.
Referring again to FIG. 7, flange reinforcing members 86, 87 may,
as by way of example and not limitation, include a plurality of
angles and substantially planar surfaces, such as forming a
corrugated reinforcing member 90, 91.
[0073] Corrugated reinforcing member 90, 91 may include sharper or
wider angles as compared to the example structure shown in FIGS. 7
and 8, and may further include rounded corners and curved surfaces.
Thus, it is to be understood that the shape of corrugated
reinforcing member 90, 91 shown in FIGS. 7 and 8 and is provided by
way of illustration and not limitation.
[0074] Referring now to FIG. 9, another configuration of flange
reinforcing members 86, 87 is shown. The substantially M-shaped
reinforcing members 94, 95 of FIG. 9 include a pair of inward
projections 98 adjacent opening 102. In accordance with embodiments
of the present invention, opening 102 is open toward webbing 14,
and is preferably substantially aligned with axis A-A of webbing
14. When placed in lower flange 78, substantially M-shaped
reinforcing member 95 is preferably inverted, as shown.
[0075] Referring now to FIG. 10, an I-joist structural member 106
in accordance with embodiments of the present invention is shown.
I-joist 106 adds to the structure of I-joist 70, and further
includes at least one enclosed flange reinforcing member 109, 110
within each of flanges 74 and 78, respectively.
[0076] In the illustration of FIG. 10, each of upper flange 74 and
lower flange 78 includes a plurality of enclosed flange reinforcing
members 109, 110 that are spaced apart from one another. However, a
single enclosed flange reinforcing member 109, 110 may be used,
depending upon the desired structural performance sought.
Preferably, enclosed flange reinforcing member 109, 110 is hollow
and includes a metal or metal alloy, as for example, an aluminum
alloy, with the dimensions and thickness of the sidewalls of the
enclosed flange reinforcing member capable of being customized and
selected based on the intended use of the I-joist. Enclosed flange
reinforcing member 109, 110 preferably extends substantially the
entire longitudinal length L of the I-joist.
[0077] As shown in FIG. 10, and in accordance with embodiments of
the present invention, enclosed flange reinforcing members 109, 110
include a substantially rectangular member. However, other shapes
are within the scope of the present invention, which may be but are
not limited to geometric shapes. By way of illustration, such other
shapes may include a triangular shape or a flattened-oval shape,
for example.
[0078] As shown in FIG. 10, in one aspect of the present
embodiment, the pair of enclosed flange reinforcing members
positioned in upper flange 74, as well as the pair in lower flange
78, are spaced apart a distance "d" that is substantially the same
as width "w" of webbing 14. However, separation distance d may be
less than or greater than width w of webbing 14.
[0079] In accordance with preferred embodiments of the present
invention, each of the enclosed flange reinforcing members is
situated within upper flange 74 or lower flange 78, wherein the
material forming upper flange 74 or lower flange 78 completely
surrounds the sides of each enclosed flange reinforcing members.
Preferably, I-joist 106 includes an HDPE material that forms the
upper and lower flanges, while the HDPE material completely
surrounds each longitudinal side of the enclosed flange reinforcing
members.
[0080] Referring now to FIG. 11A, an I-joist structural member 106'
is shown, wherein two adjacent enclosed flange reinforcing members
109, 109 and 110, 110 are used in each of upper flange 74 and lower
flange 78, respectively. Flange reinforcing members 109, 109 are
used in an upper flange 74 and may have a selected separation
distance (if any), and a like configuration may be provided for
flange reinforcing members 110, 110 in lower flange 76. Although
not required for all structural applications, flange reinforcing
members in a particular flange may be interconnected by a tie bar,
band, wire, glue, weld, pin, rivet, screw or other connecting means
111.
[0081] Referring now to FIG. 11B, in accordance with embodiments of
the present invention, reinforcing member 71 is shown within upper
flange 74. However, it is to be understood that reinforcing member
71 may be used in lower flange 78 of an I-joist, and may also be
used in other structures, such as posts and beams. Reinforcing
member 71 includes a plurality of rods 72 having a substantially
circular cross section, wherein the rods 72 are rigidly connected
by a cross member 73. The reinforcing member 71 is preferably
formed of carbon fiber or a metal alloy, such as an aluminum alloy.
Depending upon the loading conditions for the structural member,
the reinforcing member may comprise solid or hollow rods 72, with a
solid or hollow cross member 73.
[0082] In accordance with embodiments of the present invention,
I-joists may include an upper flange having a reinforcing member,
such as a corrugated reinforcing member 90, and the lower flange
may having a different type of reinforcing member, such as an
enclosed flange reinforcing member 110. Accordingly, it is within
the scope of the present invention that the upper and lower flanges
may include different types of reinforcing members. Such
configurations may be advantageous for certain design
considerations, such as where the upper and lower flanges will
experience different amounts and/or modes of loading.
[0083] Referring now to FIG. 12, in accordance with embodiments of
the present invention, an I-joist structural member 114 is shown
that includes reinforcing wedges or gussets 118 as reinforcing
members between outer upper flange 26 and webbing 14. In addition,
gusset reinforcing members 118 may also be used between webbing 14
and outer lower flange 30. Gusset reinforcing members 118 may be
formed as part of the outer flanges.
[0084] It will be appreciated by those skilled in the art that
conventional wood or composite I-joists that are constructed by
gluing the top and bottom flanges to the vertical center member are
not weather-resistant, unlike HDPE weather-resistant embodiments of
the present invention. An additional benefit of the present
invention is that the configuration can be a plain or true I-system
or a custom I-system.
[0085] Such custom configuration may include strengtheners or
deflection-reducing elements, such as having gussets 118 supporting
webbing and/or the upper and lower flanges, or having one or more
pins 136 mating the HDPE overlay and the reinforcing core, so as to
further strengthen the resulting structural members.
[0086] Referring now to FIG. 13, a partial side elevation view of
an I-joist structural member 122 is shown that includes at least
one, and more preferably, a plurality of vertical reinforcing
members 126 positioned along the exterior of webbing 14. Vertical
reinforcing members 126 increase stability, load capability and/or
load transfer characteristics of I-joist. Vertical reinforcing
members 126 are preferably spaced apart laterally and positioned
between the bottom of outer upper flange 24 and the top of outer
bottom flange 30.
[0087] Alternatively, vertical reinforcing members 126 may be
positioned between the bottom of upper flange 18 and the top of
lower flange 22, extending through the outer upper flange 26 and
outer lower flange 30. Alternatively, for I-joists not having an
outer upper flange 26 or an outer lower flange 30, vertical
reinforcing members 126 may be placed between upper flange 74 and
lower flange 78, as for example, in I-joists 70, 82, 106, and 106'
described above.
[0088] Referring now to FIG. 14, in accordance with embodiments of
the present invention, an I-joist structural member 130 is shown
that includes one or more knock-outs 134 in webbing 14. Such
knock-outs 134 are advantageous for passing conduits through the
joist framing, such as for electrical power.
[0089] Redwood and treated hemlock/fir are often used for outside
decking material because of their ability to withstand weathering
better than other lumber products. Load to deflection tests have
been conducted using I-joists according to the invention versus
wood product that would be replaced therewith. Such testing
demonstrated better performance of an I-joist of the present
invention as against redwood and treated hemlock/fir. Therefore it
will be appreciated that the present invention provides easy to
configure and weather-resistant structural members with excellent
load-bearing characteristics that enables improved load-bearing
systems for a wide variety of applications.
[0090] Referring now to FIGS. 15A-15G, in accordance with
embodiments of the present invention, additional illustrative
structural members 200 are shown by way of illustration and not by
way of limitation of the invention. These members may serve as
reinforcing configurations within the flanges for I-joists, beams,
posts, studs, or the like in horizontal or vertical structural
support systems, for a variety of purposes. An illustrative
application includes structural columns and posts for supporting
framing, such as to support dock or deck platforms, or such as
otherwise may be used to support I-joists thereunder.
[0091] Support members 200 include a core reinforcing member
surrounded by a thermoplastic material, such as HDPE. The core
reinforcing members are stiff or rigid and preferably hollow, and
may be formed of a metal or metal alloy, such as an aluminum alloy,
or may also be formed of carbon fiber.
[0092] The following configurations are described with respect to
cross-sectional views. Referring to FIG. 15A, a rectangular or
square post 200 having a plurality of rectangular core reinforcing
members 204 is shown, where members 204 are surrounded by outer
layer 208 that includes HDPE.
[0093] Referring to FIG. 15B, a rectangular or square post 200 is
shown with a single core reinforcing member 204 having a
rectangular cross section. Referring to FIG. 15C, a rectangular or
square post 200 is shown with a single core reinforcing member 204
having a circular cross section.
[0094] Referring to FIG. 15D, a circular post 200 is shown with a
single core reinforcing member 204 having a circular cross section.
Referring to FIG. 15E, a circular post 200 is shown with a single
core reinforcing member 204 having a rectangular cross section.
[0095] Referring to FIG. 15F, a circular post 200 is shown with a
core reinforcing member 204 having a triangular cross section.
Referring to FIG. 15G, a circular post 200 is shown with an core
reinforcing member 204 having a flattened oval cross section. Thus
a variety of post configurations are possible, as are a variety of
core reinforcing members, in practice of the invention.
[0096] During manufacture of the reinforcing members, or prior or
during forming an I-joist, post, or beam, the reinforcing member
may be textured to provide improved adhesion between the surface of
the reinforcing member and the HDPE. Surface texturing is
anticipated to provide better bonding between the thermoplastic
material and the reinforcing member, and thus better structural
performance.
[0097] Referring again to FIGS. 7-8, flange reinforcing members 86,
87 may include one or more apertures 88. Apertures 88 also provide
continuity between the thermoplastic material, as for example HDPE,
located above and below the flange reinforcing members 86, 87.
[0098] It will be further appreciated that surfaces of flange
reinforcing members 86, 87, enclosed flange reinforcing members
109, 110, or core reinforcing member 204, and the like, may include
a textured, scarified, and/or roughed surface and which may also
include projections or indentations as well as apertures 88. An
example of this surface treatment is generally shown in FIG. 5 as
details 66.
[0099] Referring now to FIG. 16, a structural reinforcing member
300 is provided that includes a plurality of arms extending from a
central core 304. In accordance with illustrative embodiments of
the present invention, structural reinforcing member 300 includes
four arms, including a first arm 308, a second arm 312, a third arm
316, and a fourth arm 320. The first arm 308 is preferably situated
substantially opposite third arm 316, or between about 160 to 200
degrees from third arm 316, and more preferably, about 180 degrees
from third arm 316. Similarly, second arm 312 is also preferably
situated substantially opposite fourth arm 320, or between about
160 to 200 degrees from fourth arm 320, and more preferably, about
180 degrees from fourth arm 320. In addition, first arm 308 is
separated from second arm 312 by between about 45 to 90 degrees,
and more preferably, by between about 55 to 75 degrees, and more
preferably yet, by between about 68 degrees. Similarly, third arm
316 is separated from fourth arm 320 by between about 45 to 90
degrees, and more preferably, by between about 55 to 75 degrees,
and more preferably yet, by between about 68 degrees. A structural
reinforcing member may have more than four arms and is considered
within the scope of the present invention. As for example and not
intending to limit the scope of the invention, a reinforcing member
may comprise six arms.
[0100] Structural reinforcing member 300 is encased within HDPE
structural member 328 and preferably includes a metal alloy, such
as an aluminum alloy, or carbon fiber. In accordance with several
embodiments of the present invention, central core 304 is
preferably hollow. Structural reinforcing member 300 preferably
extends the entire longitudinal length L of structural member
328.
[0101] Referring now to FIG. 17, a modified structural reinforcing
member 300' is shown, wherein structural reinforcing member 300'
includes an internal reinforcing core 332. Reinforcing core 332
adds additional strength to structural reinforcing member 300', and
allows structural member 328' including structural reinforcing
member 300' to be used in higher load types of applications, but
without the extra weight of a solid core addition.
[0102] As shown in FIG. 17, reinforcing core 332 appears as a
cross-shaped member. However, other shaped reinforcing cores are
within the scope of the present invention. As for example,
reinforcing core may include a substantially square, circular or
diamond shape in cross section.
[0103] Referring still to FIGS. 16 and 17, and in accordance with
embodiments of the invention, the exterior surface of structural
reinforcing members 300 and 300' preferably includes a surface
texturing to aid in the bonding of the surrounding HDPE with
members 300 and 300'. More particularly, an exterior rib 336 may be
provided at the exterior intersection 340 between arms 308, 312,
316 and 320 of structural reinforcing members 300 and 300'. Ribs
336 preferably extend the longitudinal length L of structural
reinforcing members 300 and 300'.
[0104] Still referring to FIGS. 16 and 17, in accordance with
embodiments of the present invention, ribs 336 may further include
fully penetrating or partially hollowed out depressions or divots
344. Divots 344 are preferably spaced apart along the longitudinal
length of ribs 336. Divots 344 serve to further anchor reinforcing
member 300, 300', that preferably includes an aluminum alloy or
carbon fiber, to the surrounding thermoplastic material, preferably
HDPE. Divots 344 assist in limiting or removing sliding tendencies
between the HDPE and reinforcing members 300, 300' when structural
members 328, 328' are under loaded conditions. In an alternative
embodiment, the reinforcing member 300, 300' may include apertures
88 that act as openings for receiving at least some HDPE when the
HDPE is extruded around the reinforcing member 300, 300'. As with
divots 344, the apertures 88 assist in limiting or removing sliding
tendencies between the HDPE and reinforcing members 300, 300' when
structural members 328, 328' are under loaded conditions.
[0105] Referring now to FIGS. 18-20, end elevation views of
structural reinforcing members 300' are shown, wherein arms 308,
312, 316 and 320 have various shapes and end shapes 348, such as
prongs or lobes. For the reinforcing members shown in FIGS. 18-20,
reinforcing cores 332 may be omitted if a hollow structural member
300 without reinforcing cores 332 is desired. Reinforcing members
300, 300' may also be solid.
[0106] In practice of an embodiment of the invention, structural
reinforcing members 300 and 300' may be used in I-joists, posts
beams, trusses, and the like, with good benefit. As for example,
FIG. 21 illustrates an embodiment of the present invention, wherein
I-joist 350 includes flange 74, 78 with reinforcing members 300,
300'. In accordance with embodiments of the present invention, for
I-joist 350 the reinforcing member 300, 300' is preferably oriented
such that a bisector "b.sub.1-2" of the angle ".alpha..sub.1-2"
between first arm 308 and second arm 312 is transverse to axis A-A
of the I-joist 350, and more preferably, bisector "b.sub.1-2" is
substantially perpendicular to axis A-A of I-joist 350. Similarly,
bisector "b.sub.3-4" of the angle ".alpha..sub.3-4" between third
arm 316 and fourth arm 320 is transverse to axis A-A of the I-joist
350, and more preferably, bisector "b.sub.3-4" is substantially
perpendicular to axis A-A of I-joist 350. I-joist 350 is
anticipated to preferably be oriented such that a compression load
or force "F" applied to I-joist 350 is substantially parallel to
axis A-A of I-joist 350.
[0107] The configuration of the reinforcing member 300, 300'
comprising a plurality of arms enhances the strength of the entire
I-joist 350. This is achieved under loading conditions when the
upper arms 308 and 320 tend to converge toward the lower arms 312
and 316, respectively, thereby binding in place the HDPE. That is,
the first arm 308 and the second arm 312 tend to converge toward
each other compressing the HDPE between them together and thereby
further locking the reinforcing member 300, 300' in place under
loading conditions. Likewise, the fourth arm 320 and third arm 316
tend to converge toward each other compressing the HDPE between
them together and thereby further locking the reinforcing member
300, 300' in place under loading conditions. In addition, the ribs
336 and associated divots 344, whether partially or fully
penetrating, keep the HDPE from traversing along the longitudinal
axis of the reinforcing member 300, 300' when under loading
conditions.
[0108] Referring now to FIG. 22, in accordance with embodiments of
the present invention, an I-joist 352 is shown that comprises a web
and flange reinforcing member 354. The web and flange reinforcing
member 354 preferably is formed of carbon fiber or a metal alloy,
such as an aluminum alloy. The web and flange reinforcing member
354 preferably comprises an assembled, integral structure that
includes webbing 356 that is connected or formed integrally with
reinforcing flange members 358 and 360. Webbing 356 may be solid or
hollow, and reinforcing flange members 358 and 360 may comprise one
of the earlier presented reinforcing members, such as reinforcing
members 300, 300', where such reinforcing members may also be solid
or hollow, and where hollow, may include a reinforcing core 332. In
addition, the webbing 356 may be solid and combined with hollow
reinforcing members. For a web and flange reinforcing member 354
made of carbon fiber, the webbing 356 is preferably thinner in
width w than a structurally equivalent webbing 14 that is made of
HDPE. As for example, the webbing 356 may be about 3/16 of an inch
in width. In accordance with embodiments of the present invention,
to form the I-joist 352, HDPE is extruded to the exterior of
reinforcing flange members 358 and 360 of web and flange
reinforcing member 354.
[0109] Referring now to FIG. 23, an end-on side elevation view of a
rim joist 362 in accordance with embodiments of the present
invention is shown. The rim joist 362 includes the web and flange
reinforcing member 354 as described above for I-joist 352, and
further comprises a substantially rectangular shaped outer member
364 encompassing the web and flange reinforcing member 354.
[0110] Referring now to FIG. 24, a side elevation view of only the
web and flange reinforcing member 354 is shown. In accordance with
embodiments of the present invention, the web 356 of the web and
flange reinforcing member 354 may include holes 366 spaced apart
along its longitudinal length.
[0111] Combining HDPE with a metal alloy, such as an aluminum
alloy, or carbon fiber, in the configurations shown and described
herein provides functionality by increasing loading strength. Under
compression or tension, the integral configuration of the
structural members, flanges and the like, serves to resist movement
from either, thereby improving load ratings. Hollow cores enable
achieving structurally sound members with some reduction of
weight.
[0112] In accordance with embodiments of the present invention, at
least one method of manufacture is also provided, the method
comprising a unique process. As one example, the method of
manufacture may comprise a dual extrusion in-line fabrication
process. It will be appreciated that the various structural
assemblies are described herein which generally may be referred to
as structural members or load members, and are preferably formed in
a sequence of separate steps. As an illustration, for example, web
member 13 and flanges 26, 30, may be formed as respective
structures prior to their assembly and formation of a structural
member, such as I-joist 10. Likewise, web member 13, channel
reinforcing members 64, 65 and flanges 26, 30, may be formed as
respective structures prior to their assembly and formation of a
structural member, such as I-joist 60. As a further example, any of
reinforcing members 71, 86, 87, 109, or 110 may be formed as
respective structures prior to formation of a structural member 82,
106, 106', or 114. As a further example, a reinforcing member 204,
300, or 300' may be formed as respective structures prior to
formation of a structural member 200, 328 or 328'.
[0113] In accordance with another embodiment of the present
invention, an illustrative method of manufacturing a structural
support member having a rated deflection loading includes: (a)
preparing a structural reinforcing member of at least length L for
bonded integration into a structural support member of at least
length L; (b) forming a structural support member preform by
feeding the structural reinforcing member into a thermoplastic
extruder and extruding the structural reinforcing member with a
thermoplastic, wherein the thermoplastic is bonded to the surface
of the structural reinforcing member along the length of at least
L; and (c) controlledly cooling the extrusion-formed structural
support member preform wherein the thermoplastic is bonded to the
structural reinforcing member along the length of at least L and
wherein the bonded thermoplastic and structural reinforcing member
share the loading of the structural support member without
separating along the at least length L when the structural support
member is loaded to the rated deflection loading.
[0114] Practice of the invention may further include preparing the
structural reinforcing member, to include forming an aluminum alloy
extrusion with a non-uniform surface, the surface extending a
length of at least L. The method may further include forming an
aluminum alloy with a non-uniform surface that includes providing
surface attributes that improve the bonding of the thermoplastic
(or thermoplastic composites, such as amended HDPE) to the
structural reinforcing member. The method may further include
preparing the structural reinforcing member to include forming an
aluminum alloy extrusion with a non-uniform surface, the surface
extending a length of at least L. Furthermore, the method may
include preparing the structural reinforcing member to include
extruding the structural reinforcing member and adjusting its
temperature by cooling.
[0115] FIG. 25 shows an illustrative method 400 for forming a
structural member of the invention, including: (a) the step 404 of
selecting the structural member, including selecting a
thermoplastic material, and a reinforcing member shape and material
type; (b) the step 408 of preparing to manufacture the structural
member, including preparation of resins and reinforcing materials;
(c) the step 412 of extruding the reinforcing member, such as
extruding an aluminum alloy reinforcing member; (d) the step 416 of
modifying, if appropriate, the reinforcing member, such as by
adding partially or fully penetrating divots or apertures,
scarifying at least a portion of the surface of the reinforcing
member, and/or otherwise providing texturizing features to the
reinforcing member that were not otherwise generated when the
reinforcing member was extruded; (e) the step 420 of cooling the
reinforcing member (which may occur before step (d) depending upon
the materials used and the nature of the modifications performed in
step 416); (f) the optional step 424 of adding any adhesives or
bonding agents to at least a portion of the surface of the
reinforcing member (such as may be necessary of a carbon fiber
reinforcing member is used in combination with HDPE outer member);
(g) the step 428 of feeding the reinforcing member, such as the
aluminum alloy reinforcing member into the HDPE extruder; (h) the
step 432 of extruding the HDPE around the reinforcing member; and
(i) the step 436 of cooling the structural member comprising the
HDPE and reinforcing member, where such cooling may be performed in
a controlled fashion.
[0116] In one embodiment, at least some of steps 412 through 436
are continuous, wherein a reinforcing member is extruded to
specification, cooled and texturized (if necessary), and then fed
into an HDPE extruder, extruded with HDPE, and then cooled to form
the desired structural member. The step 436 of cooling the extruded
structural member may accommodate for complexities in cooling the
extruded structural member having diverse materials, such as having
a HDPE over an aluminum or carbon fiber reinforcing member. This
dual in-line fabrication extrusion method has the advantage of
providing all necessary opportunity for engineered control of a
continuous manufacture process in one location. U.S. Patent
Application Publication US 2005/0108983 A1 discloses a method of
forming a reinforced extruded composite structural member, and such
publication is incorporated herein by reference in its
entirety.
[0117] To assist in the understanding of the present invention the
following list of components and associated numbering found in the
drawings is provided herein: TABLE-US-00001 Number Component 10
I-joist 13 web member 14 webbing 18 upper flange 22 lower flange 26
upper outer flange 27 upper flange assembly 29 lower flange
assembly 30 lower outer flange 34 receptacle (of the upper outer
flange 26) 38 key (of the webbing 14 and upper flange 18) 39
locking mechanism 42 key (of the webbing 14 and lower flange 22) 43
locking mechanism 46 receptacle (of the lower outer flange 30) 60
I-joist 64 channel reinforcing member 65 channel reinforcing member
66 details/surface texturing 68 opening 70 I-joist 71 reinforcing
member 72 rods 73 cross member 74 upper flange 75 strengthening
member 78 lower flange 82 I-joist 86 flange reinforcing member 87
flange reinforcing member 88 aperture 90 corrugated reinforcing
member 91 corrugated reinforcing member 94 M-shaped reinforcing
member 95 M-shaped reinforcing member 98 inward projections (of
M-shaped reinforcing member 94) 106 I-joist 106' I-joist 109
enclosed flange reinforcing member 110 enclosed flange reinforcing
member 111 connecting means 114 I-joist 118 gusset reinforcing
member 122 I-joist 126 vertical reinforcing member 130 I-joist 134
knock-outs 136 pins 200 structural member (or post) 204 core
reinforcing member (of post 200) 208 outer layer (of post 200) 300
structural reinforcing member 300' structural reinforcing member
304 central region (of structural reinforcing member 300 or 300')
308 first arm (of structural reinforcing member 300 or 300') 312
second arm (of structural reinforcing member 300 or 300') 316 third
arm (of structural reinforcing member 300 or 300') 320 fourth arm
(of structural reinforcing member 300 or 300') 328 structural
member (with structural reinforcing member 300) 328' structural
member (with structural reinforcing member 300') 332 reinforcing
core (of structural reinforcing member 300') 336 rib (of structural
reinforcing member 300 or 300') 340 exterior intersection (between
the arms 308, 312, 316, 320) 344 divot 348 end shape (of arms 308,
312, 316, 320) 350 I-joist 352 I-joist 354 web and flange
reinforcing member 356 webbing 358 reinforcing flange member 360
reinforcing flange member 362 rim joist 364 outer member 366 holes
400 method of manufacturing 404 select (reinforcing member
specifics and outer material specifics) 408 prepare (reinforcing
member and outer HDPE) 412 extruding alloy (or other reinforcing
member) 416 rib/scarify/texturize alloy (or other reinforcing
member) 420 cool alloy (or other reinforcing member) 424 apply
adhesive (optional depending upon material type of reinforcing
member) 428 feed alloy (or other reinforcing member) 432 extrude
HDPE around alloy (or other reinforcing member) 436 cool HDPE A--A
axis (of webbing 14 or joist) .alpha..sub.1-2 angle between first
arm 308 and second arm 312 .alpha..sub.3-4 angle between third arm
316 and fourth arm 320 b.sub.1-2 bisector of the angle
.alpha..sub.1-2 b.sub.3-4 bisector of the angle .alpha..sub.3-4 F
force L longitudinal length d separation distance (between
reinforcing members) w width (of webbing 14)
[0118] The present invention, in various embodiments, includes
components, methods, processes, systems and/or apparatus
substantially as depicted and described herein, including various
embodiments, subcombinations, and subsets thereof. Those of skill
in the art will understand how to make and use the present
invention after understanding the present disclosure. The present
invention, in various embodiments, includes providing devices and
processes in the absence of items not depicted and/or described
herein or in various embodiments hereof, including in the absence
of such items as may have been used in previous devices or
processes, e.g., for improving performance, achieving ease and\or
reducing cost of implementation.
[0119] The foregoing discussion of the invention has been presented
for purposes of illustration and description. The foregoing is not
intended to limit Invention to the form or forms disclosed herein.
In the foregoing Detailed Description for example, various features
of the invention are grouped together in one or more embodiments
for the purpose of streamlining the disclosure. This method of
disclosure is not to be interpreted as reflecting an intention that
the claimed invention requires more features than are expressly
recited in each claim. Rather, as the following claims reflect,
inventive aspects lie in less than all features of a single
foregoing disclosed embodiment. Thus, the following claims are
hereby incorporated into this Detailed Description, with each claim
standing on its own as a separate preferred embodiment of the
invention.
[0120] Moreover, though the description of the invention has
included description of one or more embodiments and certain
variations and modifications, other variations and modifications
are within the scope of the invention, e.g., as may be within the
skill and knowledge of those in the art, after understanding the
present disclosure. It is intended to obtain rights which include
alternative embodiments to the extent permitted, including
alternate, interchangeable and/or equivalent structures, functions,
ranges or steps to those claimed, whether or not such alternate,
interchangeable and/or equivalent structures, functions, ranges or
steps are disclosed herein, and without intending to publicly
dedicate any patentable subject matter.
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