Note: Descriptions are shown in the official language in which they were submitted.
CA 02661370 2009-03-31
FF-13472
TITLE: HIGHWAY NOISE BARRIER
FIELD OF THE INVENTION
The invention relates to an exterior noise barrier, such as would be used
along transportation
corridors, such as highways and railway lines.
BACKGROUND OF THE INVENTION
Noise barriers are erected in exterior areas where it is desired to reduce
noise transmitted from
one zone to another. Typical locations for such noise barriers are beside busy
highway and
railway corridors, where it is desired to reduce the level of noise emanating
from traffic moving
along these corridors into adjacent residential zones.
Common noise barriers are walls consisting of pre-cast reinforced concrete
wall sections
attached to appropriate support posts spaced at regular intervals. Individual
wall sections
between support posts may be unitary pre-cast wall panels or an assembly of
smaller, stacked
wall panels. Such pre-cast panels typically are solid, not hollow. Concrete
formulations used in
some such panels may include sound absorbing components, such as wood fibres.
In some noise barriers, extruded thermoplastic panels have been used, with
individual wall
sections usually being an assembly of smaller, stacked wall panels. Such
extruded thermoplastic
panels are typically hollow. The hollow internal cavities are usually left
void but, in some cases,
such cavities have been filled with sound-absorbing insulation. Such
thermoplastic panels are
made with suitable compositions so as to be adequately protected from
degradation by exposure
to ultraviolet radiation from the sun.
All such panels suffer from various problems. The concrete panels, for
example, are heavy and
difficult to manipulate during fabrication, transportation and construction.
Their heavy weight
additionally means that the support post structures must be relatively robust
so as to support the
panels safely and effectively. In addition, their hard exterior surfaces
reflect a significant amount
of sound back into the environment, where it may eventually affect persons or
activities in the
area.
On the other hand, thermoplastic panels in which the internal cavities remain
void are light-
weight and may require less robust support. However, such panels do not
necessarily provide an
effective barrier to the passage of sound. Thermoplastic panels in which the
internal cavities are
filled with sound-absorbing insulation provide a more effective noise barrier
and still remain
1
CA 02661370 2009-03-31
FF-13472
relatively lightweight, but it can be laborious and therefore expensive to
fill the internal cavities
with sound-absorbing insulation, such as by cutting to the appropriate shapes
and sizes. Like the
concrete panels, the hard exterior surfaces of thermoplastic panels can
reflect a significant
amount of sound back into the environment.
Another problem with both of such prior art structures is that it is difficult
to present decorative
options for the panels. For example, typically the noise barrier made of a
uniform material,
whether concrete or extruded thermoplastic, will have the same uniform colour
on each side of
the barrier. In addition, it can be difficult to repair such structures, or
change their colours, after
installation.
There thus remains a continuing need for an effective, lightweight noise
barrier and which may
provide certain decorative design options.
SUMMARY OF THE INVENTION
The present invention is directed, in one aspect, to a noise barrier panel
assembly having a base
panel, sound-attenuating insulation located adjacent an exterior surface of
the base panel and an
insulation retaining structure to secure the insulation in fixed relation to
the base panel. In
another aspect, the invention is a noise barrier with at least two generally
vertical support posts,
at least one wall panel with sides attached to the support posts, sound-
attenuating insulation
located adjacent an exterior surface of the wall panel and an insulation
retaining structure to
secure the insulation in fixed relation to the base panel. In yet a further
aspect, the invention is a
noise barrier retrofit kit adapted to be attached to a wall surface having at
least two channel-
defining members adapted to be mounted to the wall surface in generally
parallel spaced apart
relationship, so as to define an insulation receiving channel therebetween,
sound-attenuating
insulation adapted to be located in such channel and at least one insulation
retaining structure
adapted to be secured to the channel-defining members whereby to hold the
insulation in place.
In yet another aspect, the invention is a noise barrier having a wall surface,
at least two channel-
defining members mounted to the wall surface in generally parallel spaced
apart relationship, so
as to define an insulation receiving channel therebetween, sound-attenuating
insulation located in
such channel and an insulation retaining structure secured to the channel-
defining members
whereby to hold the insulation in place.
IN THE DRAWINGS
Preferred embodiments of the present invention are illustrated in the attached
drawings in which:
Figure 1 is a perspective view of a noise barrier according to the invention;
2
CA 02661370 2009-03-31
FF-13472
Figure 2 is a front perspective view of one section of a noise barrier
according to
the invention;
Figure 3 is a perspective view, partially cut away, of a noise barrier panel
assembly, supported along one side, according to the invention;
Figure 4 is a cross-sectional view of a noise barrier panel assembly according
to
the invention, in which a portion of the sound-absorbing insulation has
been cut away;
Figure 5 is a cross-sectional view of an alternate embodiment of a face panel
as
may be incorporated into the invention;
Figure 6 is a perspective view of a panel side structure as may be
incorporated
into the invention;
Figure 7 is a perspective view of a panel side structure as may be
incorporated
into an alternate embodiment of the invention;
Figure 8 is a front perspective view of one section of an alternate embodiment
of
a noise barrier according to the invention;
Figure 9 is a perspective view of an alternate embodiment of a noise barrier
panel
assembly according to the invention;
Figure 10 is a cross-sectional view of such alternate embodiment of a noise
barrier panel assembly according to the invention;
Figure 11 is a cross-sectional view of an alternate embodiment of the
invention as
may be used in a retrofit application.
DETAILED DISCLOSURE
Referring to Figure 1, there is generally shown a noise barrier 10 according
to the invention.
Noise barrier 10 is located adjacent a transportation corridor such as highway
T. Noise barrier
will attenuate noise moving from transportation corridor T toward areas, such
as residential
areas on the other side of noise barrier 10.
3
CA 02661370 2009-03-31
FF-13472
Noise barrier 10 comprises a series of supports, which are generally vertical
support posts 12, to
which wall panels 14 are attached. Preferably, the support posts are spaced at
pre-determined
regular intervals. As shown in Figure 2, at a minimum, in a free-standing
noise barrier 10, there
will be at least two support posts 12 and at least one wall panel 14. In some
cases, a wall panel
14 could be mounted to some other supporting structure, such as the side of a
building, with only
one end being supported by a post 12. Posts 12 are anchored to the ground by
suitable means.
As shown in Figure 2, there may be base plates 16 at the bottoms of posts 12
which would in
turn be mounted to suitable concrete walls, foundations or footings, not
shown.
Referring to Figure 3, a preferred form of support post 12 is a vertically
oriented I-beam with
flanges 18 and channels 20.
Wall panel 14 comprises at least one noise barrier panel assembly 24. In
Figure 2, wall panel 14
is shown as being comprised of five such panel assemblies 24, but any number
could be used
depending on the height of the noise barrier 10 and on the height of
individual noise barrier panel
assemblies 24.
Referring now to Figures 3 and 4, the structure of the noise barrier assembly
24 is illustrated.
Each panel assembly 24 includes a base panel 26. Preferably, base panel 26 is
extruded from a
thermoplastic material containing suitable agents to provide protection from
ultraviolet exposure;
however, other materials and manufacturing techniques could be used to
fabricate a suitable base
panel.
On an exterior surface 28 of base panel 26, sound-attenuating insulation 30 is
secured. An
example of a suitable sound-attenuating insulation material is water
resistant, low moisture
sorption ROXUL ROCKBOARDTM mineral wool fibre board insulation. Mineral wool
densities
for such mineral wool board insulation will preferably be in the range from
about 50 to 200
kg/m3 depending on degree of sound absorption required. For normal usage, a
mineral wool
density of about 100 kg/m3 has been found to be satisfactory. Such mineral
wool board insulation
may be conveniently cut into batts of rectangular cross-section and suitable
size. Preferably,
sound insulation 30 has a moisture resistant layer 60 on one surface thereof.
When the batts of
insulation 30 are placed on exterior surface 28, in the illustrated
embodiment, preferably they
will be placed so that the moisture resistant layer 60 will be on the side of
insulation 30 away
from exterior surface 28.
Although insulation 30 could be attached to surfaces 28 by any suitable means
(including
adhesive or mechanical fasteners), it is preferable that insulation 30 be
additionally retained in
place and protected from external forces and agents by an insulation retaining
structure. In the
illustrated embodiment, such structure comprises face panels 32 which extend
across the
4
CA 02661370 2009-03-31
FF-13472
insulation 30 and are attached to base panel 26 on either side of the
insulation 30. With or
without the use of adhesive, face panels 32 secure the insulation 30 in fixed
relation to base panel
26.
It is additionally preferable that structure be provided by base panel 26 to
assist in the placement
and secure retention of insulation 30. To this end, base panel 26 has channel
walls 34 which
extend outwardly from exterior surface 28, thereby defining channels 36 into
which the batts of
insulation 30 may be placed. A noise barrier panel assembly 24 may be provided
with one or
more such channels 36. In the illustrated embodiment, each panel assembly 24
has two such
channels 36 and thus each such panel assembly 24 is illustrated with two
locations where
insulation 30 is affixed and two face panels 32 are used to secure same.
Preferably, base panel 26 and face panels 32 are provided with cooperating
attachment structures
whereby the face panels 32 may be conveniently attached to base panel 26. In
the illustrated
embodiment, the outer portion of channel wall 34 is provided with a hook-
shaped lip 38
extending away from the adjacent channel 36. To cooperate therewith, face
panels 32 are
provided with face panel hook structures 40, adapted to engage with the hook-
shaped lips 38 of
base panel 26.
As previously noted, base panel 26 is preferably extruded from a thermoplastic
material, in
which case lips 38 extend the length of base panel 26 on either side of
adjacent channels 36.
Similarly, and preferably, face panels 32 will also be formed in a linear
manufacturing process,
such as steel roll-forming or extrusion of a thermoplastic material
(containing suitable agents to
provide protection from ultraviolet exposure) or other materials such as
aluminum, whereby the
face panel hook structures 40 will similarly extend the length of the face
panels 32. Although
preferable, it is not however necessary for the hook structures 38 or 40 to be
integrally
manufactured with base panel 26 or with face panel 32. Instead, separate hook
attachments or
other fasteners could be used to attach face panels 32 to base panel 26.
In assembly of a noise barrier panel assembly 24, it is possible for face
panels 32 to be
longitudinally slid into place from one end of base panel 26. Preferably
however, face panels 32
with their hook structures 40 may be transversely snapped into place. This
latter operation may
be made easier by engaging a hook structure 40 and a corresponding lip 38 on
one side of a
channel 36 and then snapping the other hook structure 40 into place over and
around the other lip
38. In a reverse removal operation, a face panel 32 may be transversely
disengaged from lips 38
on the sides of channel 36.
To provide sufficient structural integrity and to achieve the required
dimensions, panel 26 may
be provided with various internal cavities 42. In the illustrated embodiment
cavities 42 are left
CA 02661370 2009-03-31
FF-13472
void. However, if additional sound absorption is required, it would be
possible to fill cavities 42
with additional sound insulation material.
To assist in providing additional rigidity to panel assembly 24, one or more
of cavities 42 may be
provided with a stiffening member, such as the S-shaped member 44. Other
structural member
profiles, such as channels or I-beams, could be used. Such stiffening members
44 can be made
from any suitable material such as steel or in some cases aluminum.
To assist in the proper alignment and securing together of adjacent panel
assemblies 24, top and
bottom surfaces 46 and 48, respectively, of base panel 26 are provided with
cooperating upper
and lower registration structures 50 and 52. In the particular embodiment
shown, the top surface
46 is provided with outwardly extending ridge 54 and the bottom surface 48
provided with a
corresponding inwardly extending groove 56. Adjacent panel assemblies 24 may
therefore be
fitted together by engaging a ridge 54 of one panel assembly 24 with a groove
56 of a
neighbouring panel assembly 24.
As shown in Figures 3 and 6, preferably face panels 32 are provided with a
multiplicity of sound
admitting slots or openings 58. If face panels 32 are extruded or roll formed,
then openings 58
will be added in a separate stamping operation. As previously noted, when the
batts of insulation
30 are placed into channels 36, layer 60 is preferably located away from
exterior surface 28, so
that in this manner it will be adjacent to face panel 32. In this arrangement,
rain or other water
that may enter into the panel assembly 24 through openings 58 will be repelled
by layer 60 and
thus be less likely to be absorbed by insulation 30 behind face panels 32
where, particularly if
exposed to freeze-thaw cycles, there could be some risk of damage to the
structure. It must be
stated however that noise barrier 10 is not necessarily designed to be
waterproof and the entry of
at least some water into the structure is not expected to be problematic in a
normal range of
conditions.
Because the face panels 32 are separate components from the base panels 26,
various colour and
tone and other decorative options can be presented to the noise barriers
users. For example, the
face panels 32 can be of a different colour/tone compared to the colour/tone
of the base panel 26.
In addition, different colours/tones could be used for different face panels,
giving a striping
effect from top to bottom of barrier 10. In another embodiment (not shown),
hook structures
similar to lips 28 could be provided on an interior surface 29 of base panel
26. Such hook
structures would allow face panels 32 to be located on that side of the noise
barrier, so that
persons on both sides of noise barrier 10 may have different colour and tone
options and also the
option of adding additional sound-attenuating insulation. Other decorative
features (for example
solid panels, panels with different surface textures and patterns, panels with
different hole
6
CA 02661370 2009-03-31
FF-13472
patterns, shapes or sizes) may also be applied to different face panels,
giving an even wider range
of decorative options.
In addition, because the face panels 32 are separate and removable components,
face panels 32
may be changed as desired, for example either to achieve different esthetic
effects or to repair
damaged face panels.
Referring now to Figure 5, an alternate profile for a face panel 32 is shown.
The hook structure
40a illustrated, which has a tip 41a doubling back on itself, is particularly
robust and may be
useful in certain applications or for certain face panel materials.
As shown in Figures 3 and 6, wall panel 14 is of a width which is
approximately the width of
channels 20 between I-beam flanges 18. Base panel 26 may be provided with an
edge cap 21
which provides some protection to the edges of base panel 26. Sealing
structures 22 are attached
to base panel 26 adjacent edge cap 21. Wall panel 14 is securely held in place
between flanges
18 by friction by means of the sealing structures 22 of its panel assemblies
24.
Referring to Figure 7, an alternate version of an edge cap 21 a and associated
seals 22a are shown
for wall panel 14a.
In the embodiments of Figures 6 and 7, circular openings 25 have been cut in
edge caps 21 and
21 a, so as to reduce weight and material usage. The cut-out segments can be
recycled or
reprocessed.
Referring to Figure 8, there is shown an alternate embodiment of a noise
barrier 100 according to
the invention. In this embodiment, an alternate wall panel l 14 is held in
place, in generally the
same manner as previously described above, between support posts 12. As
illustrated, wall panel
114 comprises five noise barrier panel assemblies 124 but as before other
numbers could be
used.
Referring to Figures 9 and 10, panel assembly 124 comprises a base panel 26,
as described
above. In addition, batts of sound-attenuating insulation 30 are located as
described above,
except that in this embodiment if insulation 30 has a moisture resistant layer
60, preferably such
layer 60 will be located adjacent exterior surface 28. In this embodiment,
face panel 132
comprises a lattice or mesh structure. Preferably, face panel 132 is made of
wire mesh, with cells
about 6 inches by 6 inches. Face panel 132 is provided with upper and lower
hooks 140 to attach
to the lips 38 of base panel 26. In the illustrated embodiment, face panel 132
is sized to extend
across two neighbouring batts of insulation 30. In addition to face panel 132,
an inner mesh or
net 142 may be pressed into place between face panel 132 and batts of
insulation 30.
7
CA 02661370 2009-03-31
FF-13472
The purpose of the open lattice work of face panel 132 and of any inner mesh
142 is to provide a
support structure for plants, such as vines, ivies and the like, that may be
planted adjacent to the
noise barrier 100. Any moisture which may be absorbed by the insulation
material 30 will be
available to the plants.
Referring now to Figure 11, there is shown an alternate embodiment for
retrofitting sound-
attenuating insulation to an existing wall surface W, thereby converting such
wall into a noise
barrier structure 150. The retrofit components may be supplied in kit form.
The kit will comprise
at least two channel-defining rail members 152. The rail members 152 are
mounted to pre-
existing wall surface W by any suitable means, such as fasteners 154, in
generally parallel
spaced apart relationship a pre-determined distance apart from each other, so
as to define an
insulation receiving channel 156 therebetween. In normal use, rail members 152
will be
mounted generally horizontally. However, it is possible that, for artistic or
other purposes, they
could be mounted in any desired orientation. Indeed, if the area of the wall
is large enough, for
artistic purposes, the different rail member components could be provided in a
variety of
different orientations, in essence in a mosaic-type pattern. Rail members 152
have two inwardly
oriented hook-shaped lips 160.
The kit may also include batts of sound-attenuating insulation 158 which will
be located in
channel 156 adjacent the wall surface W. If the insulation has a moisture
resisting layer 162,
preferably such layer 162 will be located away from wall surface W.
The kit will additionally include at least one face panel 32. When rail
members 152 are duly
mounted to wall surface W and insulation 158 put in place, the face panel hook
structure 40 may
be slid or snapped into place into engagement with lips 160.
The wall surface W to which noise barrier structure 150 may be attached could
be the reverse
side of a wall panel of the type described above, namely wall panel 14. In
this fashion, both sides
of wall panels 14 may be made sound-attenuating as well as provide various
decorative options
as previously described.
If it is desired merely to achieve decorative effects as described above, it
is possible to attach
face panel 32 to rail members 152 without including any insulation 158 in
channel 156.
Although various preferred embodiments of the present invention had been
described herein in
detail, it will be appreciated by those skilled in the art that variations may
be made thereto
without departing from the spirit and scope of the invention.
8
