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Making Work Zones Work
BetterEffective Noise Control
During Nighttime Construction
Cliff Schexnayder, Ph.D., PEEminent Scholar
Arizona State University
and
James Ernzen, Ph.D., PEAssociate Professor
Arizona State University
Domenick Biller, New Jersey DOT
J. Conrad, Washington DOT
Steve DeWitt, North Carolina DOT
William Dowd, FHWA
Arthur Gruhn, Connecticut DOT
Fred Hejl, TRB
Crawford Jencks, TRB
J. Smythe, Iowa DOT
Erich Thalheimer, Central Artery/Tunnel Proj.
Ron Williams, Arizona DOT
Construction Nuisances
The goal is to minimize construction’s impact on abutting residents and businesses, while moving forward with the work on schedule and within budget.
CONSTRUCTION NOISE GENERATORS
PROBLEM ACTIVITESActivity Type % identifying
as Problem*
Pavement Breaking 27
Paving/Resurfacing 25
Pile Driving 24
Bridge Deck Removal 24
Rehab 206
NOISE TRANSFER SITUATION
SOURCE CONTROLS
It is a cardinal rule that, where possible, noise control should occur at the source.
Require modern equipment
Modern equipment has better engine insulation and mufflers.
SOURCE CONTROLS
Require the use of Manually adjustable or Ambient-sensitive
backup alarms.
Equipment Restrictions
POSITION OF
BACKUP ALARMS
By specification direct the use of only solar powered traffic control devices.
SOURCE CONTROLS
Equipment Restrictions
SOURCE CONTROLS
Operate at minimum power
A frequency reduction will assist in reducing perceived noise.
Use electric or hydraulic powered equipment.
SOURCE CONTROLS
Use quieter alternate equipment
PATH CONTROLSThe second line of attack is controlling noise radiation along its transmission path.
PATH CONTROLS
Enclose especially noisy activities or stationary equipment
PATH CONTROLSGrout plant enclosure for audio, visual and dust control.
Note advertising space sold on the enclosure.
PATH CONTRO
LS
PATH CONTROLS Erect noise barriers or
curtains.
Noise barriers are cost-effective when they provide perceptible noise reduction benefits to a relatively large number of receptors.
PATH CONTROLS Erect noise barriers or
curtains.
A barrier must physically fit in the space available and completely break the line-of-sight between the noise source and the receptors.
Acousticshadow
Source
High frequency cut-offLow frequency cut-off
ACOUSTIC SHADOW ZONE
PATH CONTRO
LSMay be very temporary systems mounted on jersey bases for easy relocation.
PATH CONTROLSMore permanent walls designed to last several years on long duration projects.
PATH CONTROLSAny gaps should be completely sealed.
PATH CONTROL
SAnother option for temporary noise barriers are acoustical curtains.
BARRIER COST
Barrier Type Cost per sf.
Temporary walls $10 - $15
Curtains $8 - $9
Permanent wallU.S. Gypsum, Ultrascreen
$12 - $14
6
RECEPTOR CONTROLS
When all other approaches to noise control fail a program of control at the receiver should be undertaken.
RECEPTOR CONTROLS Window treatment
program
A receptor located very close to the noise generating activity.
RECEPTOR CONTROLS
• Resident with health condition
Window treatment program
Criteria:
• Hardship situation ( infant, house-bound person)
RECEPTOR CONTROLS
• Interior glazed storm sash
Window treatment program
Measures:
• Replace window with double pane glass
• Sliding glass storm door
RECEPTOR CONTROLS Window treatment program
Cost guidelines on CA/T project:
• $800 per interior storm sash
• $2,500 per window replacement
• $5,000 total per resident
RECEPTOR CONTROLS
Temporary relocation
In very special cases temporary relocation may be necessary.
• California - earthquake repair
• One case I-15 project (medical)
• Four apartments CA/T project
COMMUNITY RELATIONS
Early communication with the public is
COMMUNITY RELATIONS
Establishment of good rapport with the community can provide high benefits at low cost.
COMMUNITY RELATIONS
Inform the public of any potential construction noise impacts and measures that will be employed to reduce the impacts.
COMMUNITY RELATIONS
INFORMATION Identify the work activity and location.
Identify the work hours and the duration of the activity.
COMMUNITY RELATIONS
INFORMATION Explain what neighbors can
expect, sounds, lights and equipment. A statement of concern about the nuisances and that every effort is being made to reduce impacts is important.
COMMUNITY RELATIONS
INFORMATION“Whenever possible, crews will point lights away from homes and will also try to move heavy equipment so that back-up alarms are angled away from homes.”
Where to get more information
Noise complaint hotline number
COMMUNITY RELATIONS
INFORMATION
COMMUNITY RELATIONS
INFORMATION Noise complaint hotline
number
COMMUNITY RELATIONS
I-15 Hotline Calls
0
1000
2000
3000
4000
5000M
ay-9
7
Jun-
97
Jul-9
7
Aug-
97
Sep
-97
Oct
-97
Nov
-97
Dec
-97
Jan-
98
Feb-
98
Mar
-98
Apr-
98
May
-98
Num
ber
of P
hone
Cal
ls
COMMUNITY RELATIONS
Establish and publicize a responsive complaint mechanism for the duration of the project.
NOISE MITIGATION COST
CA/T Noise Program Estimate
Cost Category CostDirect Expenses1 $5,326,360Indirect Expenses2 $102,000Mitigation Costs3 $4,729,600Contractor Costs4 $5,420,660
Total $15,578,6206
NOISE MITIGATION COST
Cost Category CostTotal $15,578,620
6
This mitigation effort represents about 0.15% of project cost.
What does project delay cost.