identifying vibration sensitive work...
TRANSCRIPT
Identifying Vibration Sensitive Work Zones
About The Research
FDOT Grant No. BDB-11
Report Title
Use of Nondestructive Techniques to Estimate the Allowable Vibratory Compaction Level During Construction.
Authors
N. Mike Jackson, Ph.D., P.E., University of North Florida
Michael Hammons, Ph.D., P.E., Applied Research Associates.
Robert Walker, Applied Research Associates.
Harold Von Quintus, P.E., Applied Research Associates.
Research Report Available Online at http://www.dot.state.fl.us/research-center/Completed_StateMaterials.htm
2
Background
Asphalt Density Critical for Pavement Performance
Quality Control Criteria for Hot Mix Asphalt
Compaction of Asphalt Static Rollers
Vibratory Rollers – Construction Vibration
3
Human Annoyance
Infrastructure Damage
Architectural
Structural
Construction Vibration
Types of Waves
5
P-Wave or Compression Wave (Seismic Body Wave)
S-Wave or Shear Wave (Seismic Body Wave)
Rayleigh or Surface Wave (Seismic Surface Wave)
Push-Pull
motion
Wavelength Double Amplitude
6
Construction Induced Vibrations
Energy Carried By Different Waves
P-Wave
S-Wave
Rayleigh Wave
Falling Weight Deflectometer
7
Time
Deflection
or particle
velocity
Surface Waves Surface Waves
Sensor Locations
FWD vs. Roller
Falling Weight Deflectometer
– Impact Load (Falling weight)
– Peak load range: 1.5 to 27 kips
– Typical peak load magnitude = 9 kips
Vibratory Roller
– Continuous vibration
– Operating weight range: 3 to 30 kips
Both induce ground vibration!
Identification of Vibration Sensitive Areas
A practical methodology for identifying vibration sensitive areas
– Vibratory compaction not recommended
Use FWD time histories to predict the ground oscillation from vibratory rollers
9
Vibration Descriptor
Peak Particle Velocity (PPV)
Correlates well with damage and complaints
Particle movement is mostly in vertical direction
Measured by Falling Weight Deflectometer
10
Prediction of Ground Motion
11
Bounding Predictor and Curve
0.1
1
10
0.10 1.00 10.00
Scaled Range
Peak P
arti
cle
Velo
cit
y
(in
/sec)
Peak P
art
icle
Velo
cit
y
Distance or Sensor Offset Normalized (Scaled) Distance
Peak P
art
icle
Velo
cit
y
Bounding Predictor and Curve y = 0.5704x-0.6371
0.1
1
10
0.10 1.00 10.00
Scaled Range
Peak P
arti
cle
Velo
cit
y
(in
/sec)
Normalize the distance by the
square root energy scaling law
Ground Motion Predictor Curve
Upper 95% Confidence Interval of curve fitted through FWD data
0.01
0.1
1
10
0.1 1 10
Scaled Range ft/(ft-lb)^0.5
Pea
k P
articl
e V
eloci
ty, in
/sec
Vibration Criteria
Human perception
– Subjective; depends upon individuals and circumstances
Human annoyance
– Subjective; uncomfortable for some individuals
Architectural damage
– Superficial damage such as hairline cracks in plaster
Structural damage
– Cracking in foundation, separation of masonry blocks, etc.
13
Office of Surface Mines – US Bureau of Mines
Based on Architectural damage of low-rise residential structures
Most often cited criteria
Used by FDOT for pile driving
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0.1
1
10
1 10 100
Vibration Frequency, Hz
Pea
k P
articl
e V
elo
city
, in
/sec
Maximum Allowable PPV
Architectural Damage Possible
DIN 4150 (Germany)
Based on human annoyance
Recognizes two settings: – Offices and factories
– Residencial areas
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0.1
1
10
1 10 100
Vibration Frequency, Hz
Pea
k P
articl
e V
elo
city
, in
/sec
Maximum Allowable PPV for Residential Areas
Maximum Allowable PPV for Offices and Factories
Criteria Adopted by FDOT
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Red – Architectural damage possible
Yellow – People may be annoyed, but architectural damage unlikely
Green - People may perceive vibration, but annoyance is unlikely
German DIN 4150 Criteria
US OSM Criteria
Analysis Procedures
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Use FWD to
characterize site
Predictor Curve
FWD
CRITERIA
Operating
Frequency of
vibratory roller
Convert scaled range to actual
distance using the energy of the
vibratory roller
Obtain PPV
threshold
Field Verification
Re-Paving Accelerated Pavement Test Tracks at the State Materials Office of the Florida Department of Transportation
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Vibration Monitoring Plan
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LA
NE
2
LA
NE
5
LA
NE
3
LA
NE
4
LA
NE
6
LA
NE
7
N
LA
NE
1 53
03
55
32
54
01
52
98
5304
5305
5304 Unit Number
Fixed Unit
Moving Unit
(Relocated as
paving
operations
moved from
lane to lane)
LEGENDUnits 5401 and
5532 were set
to record full
time histories
LA
NE
2
LA
NE
5
LA
NE
3
LA
NE
4
LA
NE
6
LA
NE
7
N
LA
NE
1 53
03
55
32
54
01
52
98
5304
5305
5304 Unit Number
Fixed Unit
Moving Unit
(Relocated as
paving
operations
moved from
lane to lane)
LEGENDUnits 5401 and
5532 were set
to record full
time histories
Office
Building
Caterpillar CB-634C
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Scaled Vibration From Compactor
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0.01
0.1
1
10
0.1 1 10
Scaled Range ft/(ft-lb)^0.5
Pea
k P
articl
e V
eloci
ty, in
/sec
FDOT Example
Public Complaint
Increased Vibration after Patch Installation
Human Annoyance
Plaster Wall Damage
Asphalt Patch
FWD Survey Results
18 kip Single Axle Modeled
Building is Approx. 90 ft. from Pavement Edge
In Green Zone!!
Vibration Monitor Results
Vibration Monitored
– 2 Monitors Set to Report PPV and Frequency
– 2 different Days
All PPVs in Green zone
0.001
0.01
0.1
1
10
1 10 100
Pe
ak P
arti
cle
Ve
loci
ty (
in/s
ec)
Frequency (Hz)
On Brick Entrance to Office In Hedge by Entrance
0.001
0.010
0.100
1.000
10.000
1 10 100
Pe
ak P
arti
cle
Ve
loci
ty (
in/s
ec)
Frequency (Hz)
On Brick Entrance to Office On Entrance Driveway
DAY 1 DAY 2
Conclusion - FDOT Example
Building is in the Green Zone
Architectural Damage Unlikely
Implementation of Algorithm
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