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It's called "THE
BIG DIG". Boston's Central Artery and Harbor Tunnel project
is the largest highway construction job ever undertaken in
the United States...at a cost over $11 billion dollars!
One sensitive issue of such a significant project is how construction
noise will impact local businesses and residences. Quincy
Marketplace, a unique, open-air collection of restaurants,
shops and offices, is located adjacent to a section of the
project requiring working underneath an overhead highway,
while a densely populated residential area is located on the
opposite side. Thus, the noise impact upon the Marketplace
and residences is even greater from the direct construction
noise as well as the reflected noise off the deck.
Neva Associates,
the local Sound Seal distributor, working in conjunction
with the Noise Control Division of the Central Artery Commission,
determined that Sound Seal BBC-13-2" Acoustical Curtain
Panels would offer the required noise reduction. BBC-13-2"
Acoustical Curtain Panels are a combination of a 2" thick
vinyl-faced Quilted Fiberglass Sound Absorber and a 1 lb
PSF reinforced loaded vinyl noise barrier. Modular Panels
are constructed with grommets for attaching to the framework
as well as exterior grade hook and loop fasteners for joining
adjacent panels together. United Process manufactured and
shipped over 400 such panels within a three week period.
As the panels were being installed, preliminary sound level
testing showed a 9 to 10 dB(A) reduction in noise levels
even before the entire job site was buttoned up. This was
just the kind of noise reduction promised to the local community.
Many other sections
of the massive project have also utilized the Sound Seal
Curtain Panels with even better results since they were
not located below an overpass, with completed sections showing
noise reductions up to 12 dB(A). A common treatment is to
have the Sound Seal Curtains installed on fence posts inserted
in pre-cast concrete highway barriers. This allows for the
noise reduction treatment to be easily relocated along with
the highway barriers.
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Sound
Seal's BBC Panels are tough enough to be used at any
job site.
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In conjunction
with the Noise Barrier/Sound Absorption Walls, United Process,
Inc., , has also manufactured a significant quantity of
portable "Hoistable Curtain Enclosures". The BBC-13-2" Acoustical
Curtain Panels are installed on heavy duty frames to drop-over
jackhammer operations during that phase of construction.
The jack-hammer
operator works inside the three-sided roofed enclosure to
screen that very loud operation from the neighbors. The
enclosure is then lifted by crane and dropped onto the next
section they are working on. By combining a sound absorber
with a noise barrier at construction projects such as these,
the Sound Seal Acoustical Curtain Panels offer noise reduction
for construction workers as well as serving the primary
purpose of keeping noise levels at a minimum in the neighborhood.
| These
are just a few examples of how United Process' Sound
Seal Acoustical Products quiet "THE BIG DIG". |
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Sound
Transmission Loss (dB) Octave Band Center Frequencies
(Hz)
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| Curtain
Product |
125
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250
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500
|
1000
|
2000
|
4000
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STC
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| BBC-13-2" |
13
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20
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29
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40
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50
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55
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32
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Sound
Absorption
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Octave
Band Center Frequencies (Hz)
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| Curtain
Product |
125
|
250
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500
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1000
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2000
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4000
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NRC
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| BBC-13-2" |
.07
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.27
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.96
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1.13
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1.08
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.99
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.85
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