U.S. patent application number 12/047036 was filed with the patent office on 2009-09-17 for foam-concrete rebar tie.
Invention is credited to Steven J. Nelson.
Application Number | 20090229214 12/047036 |
Document ID | / |
Family ID | 41061443 |
Filed Date | 2009-09-17 |
United States Patent
Application |
20090229214 |
Kind Code |
A1 |
Nelson; Steven J. |
September 17, 2009 |
FOAM-CONCRETE REBAR TIE
Abstract
A fastener is disclosed having a an extension portion configured
to be inserted into a first construction material such as foam, and
having a stirrup portion configured to retain portion of a second
construction material, such as rebar at a distance from the first
construction material. A third construction material such as
concrete can then be inserted (poured) in contact with the first
construction material and surrounding the second construction
material such that the second construction material is not directly
in contact with the first construction material.
Inventors: |
Nelson; Steven J.;
(Bellingham, WA) |
Correspondence
Address: |
HUGHES LAW FIRM, PLLC
5160 Industrial Place,#107
Ferndale
WA
98248-7819
US
|
Family ID: |
41061443 |
Appl. No.: |
12/047036 |
Filed: |
March 12, 2008 |
Current U.S.
Class: |
52/700 |
Current CPC
Class: |
E04C 5/20 20130101 |
Class at
Publication: |
52/700 |
International
Class: |
E04C 5/16 20060101
E04C005/16 |
Claims
1. A rebar holding member configured to be positioned in a foam
material having an outer surface, the rebar holding member
comprising: a. an extension portion having a longitudinal axis, the
extension portion having a plurality of barb members extended
radially outward from the longitudinal axis; b. a base portion
having a base surface located in a forward longitudinal direction;
c. a stirrup portion having a base region and a rebar holding
region, the rebar holding region comprising first and second arms
comprising an interior surface configured to hold a rebar member
therein; d. whereas the base region maintains a minimum prescribed
distance from the base surface which is configured to be placed
adjacent to the foam material.
2. The rebar holding member as recited in claim 1 where the
plurality of barb members are arranged such that a longitudinally
rearward barb member extends radially further outward than a
longitudinally forward barb member.
3. The rebar holding member as recited in claim 1 where the
plurality of barb members comprise a first transverse axis and a
second transverse axis where a first set of barbs are aligned
substantially in the direction of the first transverse axis and a
second set of barbs are aligned substantially in the second
transverse axis direction.
4. The rebar holding member as recited in claim 3 where the first
set of barbs are spaced so as to be longitudinally offset and
interposed between the second set of barbs.
5. The rebar holding member as recited in claim 4 where the second
set of barbs substantially extend in the second transverse
direction and comprise a perimeter flange portion which extends in
the first transverse direction.
6. The rebar holding member as recited in claim 1 where the
interior surface of the rebar holding region has a plurality of
radially inward extensions having a width sufficiently narrow so
the extensions undergo plastic deformation when the rebar is placed
between the first and second arms of the rebar holding region.
7. The rebar holding member as recited in claim 6 where the width
of the radially inward extensions are less than one half the width
of the first and second arms.
8. The rebar holding member as recited in claim 7 where the rebar
holding member is configured to hold the rebar in an inverted
manner.
9. The rebar holding member as recited in claim 1 where the first
and second arms each provide an inward slanting surface defining a
central open region configured to have a portion of rebar pass
therethrough.
10. The rebar holding member as recited in claim 9 where the rebar
is operatively configured to be held within the interior surface of
the rebar holding region when the rebar holding region is
positioned beneath the extension portion.
11. The rebar holding member as recited in claim 1 where the
extension portion, base portion, and stirrup portion are formed a s
a unitary structure.
12. The rebar holding member as recited in claim 11 where the
unitary structure is substantially formed as a polymer.
13. A device comprising: a. an extension portion operatively
configured to be inserted into a portion of resilient material
wherein the extension portion further comprises; i. a plurality of
orthogonally extending base members; and ii. a plurality of barb
members; b. a base portion having a first side and a second side,
the first side coupled to the extension portion; c. a stirrup
portion coupled to the second side of the base portion, the stirrup
portion operatively configured to hold a portion of construction
material.
14. The device of claim 13 wherein the extension portion, base
portion, and stirrup portion are formed as a unitary structure.
15. The device of claim 14 wherein the unitary structure is formed
of a polymer.
16. The device of claim 13 wherein the resilient material is
substantially a foam material.
17. The device of claim 13 wherein the portion of construction
material is a length of rebar.
18. The device of claim 13 wherein the portion of construction
material is a length of tubing.
Description
BACKGROUND OF THE DISCLOSURE
[0001] Foam concrete structures are utilized in various capacities
ranging from concrete stairs, drive ways, ramps, floating docks,
precast walls, abutments, retaining walls with lightweight fill
load distribution slabs, roadways and applications for concrete
foam systems such as Geofoam.TM. and other applications for
concrete foam structures. In general, a foam concrete structure has
a central region comprised of foam material which may be expanded
polystyrene (EPS) or extruded polystyrene (XEPS) with a perimeter
portion of concrete therearound. Oftentimes, a tensile strength
member such as rebar is positioned within the concrete. At present
time, rebar, which is comprised of steel or other iron-based
compositions, is a primary form of enhancing the strength of
concrete to reinforce concrete structures. In general, concrete is
very poor in tension, and having an insert therein, for example a
metallic member such as a longitudinally extending piece of rebar,
significantly enhances the strength of the concrete structure.
[0002] Now in the case of having a concrete block with a foam
center portion, when a bending moment is placed upon the structure,
there is a compressive force at its greatest magnitude in one
portion of the block structure, whereas the opposing portion has a
tensile stress imposed thereon. The concrete is used to encapsulate
or provide a protective shell, for example: floatation, geofoam,
floor systems, ICF's, poured-in-place and pre-cast concrete
systems. The foam portion functions as floatation, lightweight
fill, or insulation. Of course, the center portion has a shear
force acting as welt pursuant to basic beam theory. Therefore,
having a properly spaced tensile member such as rebar positioned in
the foam concrete structure is important for properly positioning
the rebar in the concrete to absorb the tensile stress placed
thereon.
[0003] The prior art has failed to present a system, apparatus and
method for properly positioning and orienting rebar at a proper
depth within the outer concrete perimeter region. In some forms the
rebar is positioned during a construction state in vertically and
inverted orientated positions as well as a regular horizontal
position. Therefore, in one form, having an apparatus to orientate
the rebar in various orientations with respect to the flux field of
gravity is desirable for constructing and forming a concrete/foam
structure.
[0004] Further, having a proper anchoring system to attach to the
foam material allows for proper positioning of the rebar holding
unit. In one form, having a properly sized and dimensioned base
portion allows for a sufficient amount of stability, without
requiring excessive force to penetrate the foam to be mounted
during production. These steps may be carried out in a
manufacturing facility, or on a job site.
SUMMARY OF THE DISCLOSURE
[0005] The structure in one form described in this disclosure is a
holding member having an extension portion, a base portion, and a
stirrup portion. The extension portion is configured to be inserted
into a rigid construction material such as a block of foam. The
extension portion in one form comprises a plurality of base members
with barbs which extend radially outward from the longitudinal axis
of the extension portion. These barb members are constructed to add
rigidity to the structure, and assist in proper positioning within
the rigid construction material. These barb members are especially
helpful in preventing rotational and longitudinal movement of the
holding member in relation to the foam. In one form, a plurality of
barb members extend from the barb members to further maintain the
position of the extension within the first construction material.
The extension portion may be directly coupled to or formed with the
stirrup portion, or an intermediate base portion may be provided
between the two. This base portion can provide a stop which will
limit the depth to which the extension member can be inserted into
the foam. All three elements may also be formed as a unitary
structure, say of a polymer or metal.
[0006] In one form, after inserting the extension portion of the
structure into the rigid construction material, a portion of an
elongate construction material, such as a length of rebar, is
coupled to the stirrup portion of the structure to hold the rebar a
specified distance from the rigid construction material. After the
rebar is positioned within the stirrup, another construction
material such as concrete can be disposed in contact with the first
construction material and substantially surrounding the second
construction material. This will substantially encapsulate the
construction materials and form a protective shell with the rebar
adding support to the concrete (second material).
[0007] In one form, the barb members previously discussed also have
a plurality of barb-like extensions which are configured to keep
the structure from pulling out of the rigid construction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 shows a side view taken along a first transverse axis
of the rebar holding member;
[0009] FIG. 2 shows another side view taken along a first
transverse axis;
[0010] FIG. 3 is looking longitudinally rearward along the support
portion of the rebar holding member;
[0011] FIG. 4 is taken from a longitudinally forward vantage point
looking at the extension portion of the rebar holding member;
[0012] FIG. 5 is a progressive view of a method of manufacture of a
foam concrete block structure;
[0013] FIG. 6 shows a rebar positioned in a stirrup region of the
rebar holding member which is embedded in the foam;
[0014] FIG. 7 shows a completed foam concrete structure with
concrete in the outer perimeter region having a foam center
region.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] As shown in FIG. 7, there is an environmental view of a foam
concrete structure 20. In general, the foam concrete structure 20
comprises a foam material 22 and a concrete perimeter 24. Further
comprising the foam concrete structure 20 are tensile stress
members such as rebars and rebar holding members 28. Further, in
one form of manufacture, an outer mold member 30 can be utilized to
hold the concrete 24 in its position while in an uncured state.
This outer mold member 30 can either be a part of the veneer of the
structure, or be removed from the concrete perimeter 24 once the
concrete cures or otherwise is sufficiently rigid to hold its
stationary form.
[0016] Therefore, it can be appreciated that the tensile stress
member 26, which is most commonly rebar at the time of this
writing, is positioned at a substantially center region 32 within
the concrete perimeter 24. This positioning allows the rebar 26 to
engage the surrounding concrete so as to transfer force thereto, so
when for example the particular concrete perimeter wall section 34
is in tension, these tensile stresses are transferred to the rebar
26 properly, whereas the concrete aggregate itself is in general
very poor at handling tension, and of course very strong in
compressing as is well-known pursuant to conventional material
science theory.
[0017] Therefore, as described in detail herein, the rebar holding
member 28 provides utility in properly positioning the rebar during
the production and manufacture of the foam concrete structure 20.
Various attributes of one form of a rebar holding member will be
described herein in detail with the understanding that other forms
could be utilized without departing from the spirit and scope of
the Applicant's broad concept.
[0018] In another embodiment, a section of tubing can be utilized
instead of the tensile stress member 26. This would not only add
rigidity to the material but would also add a channel for applying
fluids, gases, or serve as a conduit for electrical or
communication service. For example, once the structure is
completed, hot water could be provided through the tubing which
would heat the structure adjacent the tubing.
[0019] Referring now to FIG. 1, there is shown a side profile view
of the rebar holding member 28. To aid in the general description,
the axes system 10 is provided where axis 12 indicates the
longitudinal forward direction. Referring ahead now to FIG. 4,
there is shown a first transverse axis 14 and a second transverse
axis 16. In general, the axes 14 and 16 extend radially outward
from the longitudinal center axis 12''. In one form these axes are
orthogonal to one another, but of course the general directions of
the structures related to these axes need not be orthogonal.
[0020] Referring now to FIG. 1, it can be appreciated that in
general the rebar holding member 28 has an extension portion 36 and
a support portion 38. Interposed between the extension portion 36
and the support portion 38 is a base portion 40 which in one form
is a transverse extending planar member configured to be positioned
adjacent to the outer surface 96 of the foam center 22 described
herein with reference to FIG. 5.
[0021] In general, the extension portion 36 is configured to be
positioned in the foam material 22 in a manner as shown in FIG. 5.
The foam material in one form may be expanded polystyrene (EPS) or
extruded polystyrene (XEPS). By way of background, one form of a
foam concrete structure is a concrete dock where the interior
portion is comprised of foam material. The perimeter portion can be
between 1 and 3 inches of concrete or more. Rebar being placed in
this perimeter region, as shown in FIG. 6 and FIG. 7, greatly
enhances the structural integrity of the foam concrete structure 20
(see FIG. 7).
[0022] Therefore, it can be appreciated that the extension portion
36 must provide a reasonably stable platform when inserted within
the foam. As shown in FIGS. 1 and 2, there are first and second
base portions 46 and 48. In one form these base portions are
orthogonal to one another as shown in FIG. 4, but of course need
not be orthogonal to one another. As shown in FIGS. 1 and 2, each
of the first and second base portions 46 and 48 comprise a
plurality of barb members. As shown in FIG. 2, the plurality of
barb members 50 generally comprise, in one form, three barb members
50a, 50b and 50c. In one form the barb members are of a similar
radial width from a center longitudinal axis 12' as shown at 50a
and 50b, and in another form the barb members reduce in their
radial width extension, such as where the barb 50c is shorter than
the barb 50b. In general, the barbs provide a transverse extension
where in particular the plurality of barbs 50 extend in the first
transverse direction 14 as shown in FIG. 4, and provide a
locking-like action when extended within the foam material.
[0023] Now referring to FIG. 1, it can be appreciated that the
plurality of barb members 52 are shown, and more specifically in
one form there are three sets of barb members 52a, 52b and 52c. In
one form, the plurality of barb members 52 can have (as shown in
FIG. 2) a perimeter flange 54 which basically extends slightly
outward from the surfaces 56 and 58 of the second base member 48.
Present analysis indicates that this perimeter flange extension
provides extra gripping of the foam material when inserted therein.
Further, it can be appreciated that the barb members have a leading
surface 60, which is configured to engage the foam material when
thrust therein. As shown in FIG. 1, the trailing surface 62 is
provided which is configured to engage the foam material to
maintain the extension portion 36 mounted firmly in the core foam
structure 22 (see FIG. 7).
[0024] With the foregoing description in place with regard to the
extension portion 36, there will now be a discussion of the support
portion (otherwise referred to as a stirrup portion) 38 with
initial reference to FIG. 1. As shown in FIG. 1, in one form the
support portion 38 is comprised of a base region 70. The base
region 70 in one form can be comprised of base extensions 72 and
74. Positioned in the longitudinally rearward region of the support
portion is a support 74 which comprises first and second arms 76
and 78. The first and second arms comprise an interior surface 80,
which is configured to hold a tension member, such as a rebar 26 as
shown in FIG. 5. In general, the interior surface can have a
longitudinally outward region 82 which encompasses the cylindrical
rebar member 26 so as to lock it in place therein. Further provided
in the support 74 are the radially inward extension/fins 84 as
shown in FIG. 1 and FIG. 3 within the stirrup 80. In general, the
radially inward extension is configured to have a width 86 which is
such that the stresses placed thereon when a rebar member is placed
in the radially inward extensions plastically deform and mesh to
the rebar to further lock the rebar in place. This deformation is
particularly advantageous because it prevents the rebar from
repositioning or otherwise slipping along the longitudinal axis of
the rebar, such as if the rebar is positioned in a more vertically
oriented manner. Therefore, the width 86 would be somewhat less
than the width 88 is shown in FIG. 3, depending upon the material
used. Using a plastic injected molded unitary piece to construct
the rebar holding member 28, a desirable plastic may have a
durometer rating between 50 and 100 made from nylon, polyethylene,
or other suitable material.
[0025] As further shown in FIG. 5, in one form the first and second
legs 76 and 78 each comprise an inward slanting surface 90 and 92.
The surface of course facilitates positioning the outer surface 27
of the rebar member 26 into the central chamber region 94 of the
support portion 38. Still referring to FIG. 5, the base portion 40
generally comprises a base surface 94 positioned in a
longitudinally forward direction, which is configured to engage the
outer surface 96 of the full material 22.
[0026] To further describe one form of the rebar holding member 28,
the plurality of barbs 50 and 52 as shown in FIGS. 1 and 2 are
arranged such that, for example, the barb 50a is offset by
approximately 90.degree. and interposed between the barbs 52a and
52b. Present analysis indicates that this transversely offset and
interposed relationship provides greater engagement of the
surrounding foam material when the extension portion 36 is embedded
within the foam 22 as shown in the lower portion of FIG. 5. Of
course other forms of a barb can be employed and the above
description is one form of carrying out the applicant's
concept.
[0027] Analysis upon the overall dimensions of the rebar holding
member 20 will now be presented. As shown in FIGS. 1 and 2, these
dimensions are in one form substantially to scale, and in one form
95% of an actual prototype. Of course the scope of the concept is
not limited to the specified dimensions of the figures; however,
for purposes of included subject matter, the figures are to scale
of one embodiment (plus or minus 20%) as to the actual dimensions
and the relative dimensions between portions of the rebar holding
member 28 itself. In other words, it has been found that having a
length from the most forward location 96 from the base surface 94
of approximately 3 11/16'' provides a desirable combination of
stability of the rebar holding member 28 when fully embedded in the
foam 22 (see FIG. 6), and ease of force required to position and
force the extension portion 36 in the foam. Further, having the
first and second base portions 46 and 48 which extend
longitudinally provide a sufficient amount of rigidity to hold the
rebar and further provide a sufficiently narrow cross-section (see
FIG. 4) to fit within the foam material 22, which as noted above,
in one form is EPS. The stirrup can be higher, for example
three-six inches (plus or minus say 20% in broader range), such as
when utilizing a low distribution slab where the layer of concrete
may be a thick layer so the rebar is positioned substantially in a
central region thereof. In the broader scope, with a low
distribution slab of say twelve inches, the stirrup region can
extend vertically six inches or more. Even with the longer stirrup
region, it has been found using the EPS foam that having the
distance of approximately just under 4 inches (.+-.30% in one form
depending on the nature of the foam) provided a desirable
combination of stability and ease of force depressing within CPS
foam.
[0028] Therefore, as shown in FIG. 5, the force vector 100 is
applied to the rebar holding member 28. The force 100 can be by way
of an impact force such as a mallet-like member, or directly pushed
by one who is constructing a foam concrete structure. When the
extension portion 36 is fully inserted or at least substantially
inserted within the foam 22, in one form the base surface 94 is
pressed thereagainst and the rebar 26 can be properly positioned
within the central chamber region 94. As shown in FIG. 6, a
plurality of rebar members 26a and 26b can be positioned within the
various rebar holding members 28. The support portion 38 is
generally arranged to position the rebar a prescribed distance 102
from the outer surface 96 of the foam 22 (EPS in one form), and
further positioned a prescribed distance 104 from the interior wall
108 of the outer mold member 30.
[0029] FIG. 6 illustrates one method of manufacture where some form
of outer mold member 30 is utilized in a lower wail or a lateral
wall as shown in FIG. 6. This outer mold member 30 can be a part of
the final structure or removed thereafter. The interior wall 108
positions the un-cured concrete and maintains the desired form of
the concrete until the concrete cures. The upper region 110 can
additionally be poured and have concrete filled therein as shown
FIG. 7. Therefore, it can be appreciated that a foam concrete
structure 20 can be more readily constructed with a higher degree
of confidence of the orientation in position of the rebar contained
therein. The rebar may be specified to be positioned in a central
region of the overall width of the concrete layer, such as the
region indicated at 32 in FIG. 7.
[0030] In general, the device can be utilized in various forms,
such as concrete sandwich panels, which in one form are poured in
place, or alternatively can be pre-cast. Further, the device can be
utilized in other forms, such as insulated heated floors, or
further, precast concrete joists, decking, floors, or roofs and
various compositions thereof. For example, the device could be
utilized similar to decking for insulated reinforced concrete floor
such as Decklite.TM. from Benchmark Foam, Inc. and other similar
products from other manufactures.
[0031] While the present invention is illustrated by description of
several embodiments and while the illustrative embodiments are
described in detail, it is not the intention of the applicants to
restrict or in any way limit the scope of the appended claims to
such detail. Additional advantages and modifications within the
scope of the appended claims will readily appear to those sufficed
in the art. The invention in its broader aspects is therefore not
limited to the specific details, representative apparatus and
methods, and illustrative examples shown and described.
Accordingly, departures may be made from such details without
departing from the spirit or scope of Applicants' general
concept.
* * * * *