MINGJIANG TAO, PH.D., P.E. WORCESTER POLYTECHNIC INSTITUTE JANUARY, 2011 Update LADOTD Policy on Pile Driving Vibration Management (09-1GT)
MINGJIANG TAO, PH.D., P.E.WORCESTER POLYTECHNIC INSTITUTE
JANUARY, 2011
Update LADOTD Policy on Pile Driving Vibration Management (09-1GT)
Presentation Outline
Research Objectives
Methodology
ResultsThreshold PPV limitsApproach to determine a pre-construction
survey distance & a monitoring distance
Conclusions and Recommendations
Research Incentives
http://www.georisk.se/web/page.aspx?pageid=29013
How large a vibration monitoring area is enough?
Strongly dependent on:
• soil conditions
• dynamic sources
• susceptibility of structures
Research Objectives
Update current LA DOTD policy, and provide implementable recommendations for monitoring and control of ground and structure vibrations
Methodology
Methodology
Literature Review
Questionnaire Survey
Collect data from case history project in Louisiana
Data analysis
Pile driving, wave propagation, & wave attenuation
Scaled-distance concept
Preconstruction survey distance vs. vibration monitoring distance
Pile
Rsurvey
Rmonitoring
structural damage: PPV<0.5 in/s
Rmonitoring=Rsurvey
Determine pre-construction survey distance
Estimate the Monitoring Area Range
1. Upper limit PPV
2. Determine threshold PPV
value
3. SD corresponding to
threshold PPV
Chart PPV vs. SD
0.01
0.1
1
10
0.1 1 10
PP
V(i
n./
s)
Scaled distance(ft/sqrt(ft-lbs))
Scaled Distance(horizontal, Max Rated Energy)-PPVk=0.93, n=1
0.5
Step 1
Step 2
Step 3
Determine pre-construction survey distance
Mon
itori
ng D
ista
nce
(ft)
Rated Energy (ft-lbs)
Monitoring Distance vs. Rated Energy
Rated Energy of the Hammer Applied
Vibration Monitoring Distance
Step 44. Vibration monitoring
distance
Step 1: Determine vibration monitoring distance
A statistical approach:• Best-fit line• Confidence level line• Prediction level line
Back-calculation approach (best-fit line)
Determine vibration monitoring distance: Step 1
Confidence level line: 95 % Confidence Interval ─ if you collected ground vibration data many times, 95 times out of 100, the mean of the dataset would be in this range.
Prediction level line: 95 % Prediction Interval means that about 95 % of the time, the next ground vibration measurement you make will be inside this interval.
Step 2: Threshold PPV value
Maximum Peak Particle Velocity That Varies with Frequency
0.1
1
10
1 10 100
PAR
TIC
LE V
ELO
CIT
Y, in
/sec
FREQUENCY, Hz
RI 8507 APPENDIX B. -- ALTERNATE BLASTING LEVEL CRITERIA
0.5 in/s Plaster0.75 in/s DrywallOSM Modificaton
0.03 in
0.008 in
2 in/s
0.5 in/s
0.75 in/s
1. USBM criteria
Current LA DOTD specification
Determining threshold PPV value
2. Germany criteria
Current LA DOTD specification
Determining threshold PPV value
3.The Swedish Standard
Determining threshold PPV value- The Swedish Standard
Residential house: V= 9 x 1.00 x 0.75 x 0.60 = 4.05 mm/s (0.16 in/s) This value is less than 6 mm/s (0.24 in/s) used as a
limit for human response in the German Standard DIN 4150 (1986).
Industrial building: V = 9 x 1.20 x 1.20 x 1.00 = 12.96 mm/s (0.51 in/s) This value is very small for industrial building built
with reinforced concrete, steel, and pile foundations.
Too conservative
Determining threshold PPV value-Russia criterion
4. Russia Limits of Structure Vibration The frequency-independent safe limit of 51 mm/s (2
in/s) can be chosen for the PPV of structural (not ground) vibrations for multi-story residential, commercial and industrial buildings.
There will be practical obstacles for LA DOTD implementing this criterion
Determining threshold PPV value
5.Maximum Peak Particle Velocity Independent of Frequency (by Woods 1996)
Structure and ConditionLimiting Particle Velocity
(in./sec) (mm/sec)Historic and some old
structures 0.5 (12.7)
Residential structures 0.5 (12.7)New residential structures 1.0 (25.4)
Industrial building 2.0 (50.8)Bridges 2.0 (50.8)
Threshold PPV limits for LA DOTD
Structure and ConditionLimiting Particle Velocity
(in./sec) (mm/sec)Historic and some old
structures 0.1 (2.5)
Residential structures 0.5 (12.7)New residential structures 1.0 (25.4)
Industrial building 2.0 (50.8)Bridges 2.0 (50.8)
o Simple and easy to be implemented.o Reasonably conservative: assumed a magnification factor of 4, structural vibration is 2 in./sec.
Threshold PPV limits-Further confirmation with dynamic FEM simulations
Results
Collected Available Data
(a) a list of necessary data and information required for pile-driving vibration risk management
Available Information Huey P. Long Bridge Widening Project
Millerville Road over Honey Cut Bayou
Bayou Plaquemine Bridge Replacement Project
The Rigolets Pass Bridge Project
Project Description √ √ √ √Hammer and Pile Details √ √ √ √Penetration Depth Data √ √Energy transferred to Plies √Vibration Monitoring √Soil Profile √ √ √ √PPV 3 directional Velocity √ √ √
Velocity Vector √ √ √Max PPV √ √ √ √
0.001
0.01
0.1
1
10
0.1 1 10
Peak
Par
ticle
Vel
ocity
(in.
/s)
Scaled Distance (ft/sqrt(ft-lbs))
Millerville Bayou Road Rigolets Bayou Degleises
Causeway Tickfaw Amite HPL
PPV = 0.080(SD)-0.679
R2=0.404
PPV = 0.015(SD)-1.494
Woods & Jedele’s, Soil II
PPV = 0.081(SD)-1.11
Woods & Jedele’s, Soil III
0.001
0.01
0.1
1
10
0.1 1 10
Peak
Par
ticle
Vel
ocity
(in.
/s)
Scaled Distance (ft/sqrt(ft-lbs))
Millerville Bayou Road Rigolets Bayou Degleises
Causeway Tickfaw Amite HPL
PPV = 0.350(SD)-1.0
PPV = 0.080(SD)-0.679
R2=0.404
PPV = 0.211(SD)-1.0
PPV = 0.015(SD)-1.494
Woods & Jedele’s, Soil II
PPV = 0.081(SD)-1.11
Woods & Jedele’s, Soil III
PPV = 0.1(SD)-1.0
0.01
0.1
1
10
0.1 1 10
Peak
Par
ticle
Vel
ocity
(in.
/s)
Scaled Distance, SD (ft/sqrt(ft-lbs))
Millerville Bayou Road RigoletsBayou Degleises Causeway TickfawAmite HPL
PPV = 0.350(SD)-1.0
PPV = 0.211(SD)-1.0
0.5
0.70.4
Pre-Construction Survey Distance
Determine vibration monitoring range
Step 4 ( , PPV=0.5 in./s, (Hammer energy transfer efficiency=50%)
Hammer ModelRated energy (W) (ft‐lbs)
Monitoring distance (ft)
Monitoring distance (ft)
Monitoring distance (ft)
Bruce SGH‐3013 hydraulic hammer 282,100 158.5 262.9 133
DELMAG D46‐23, Diesel Hammer 105,000 96.7 160.4 81
PILECO, D19‐42, Diesel Hammer 42,480 43.8 72.6 52Boh/Vulcan 08 24,000 50.0 82.9 39Boh/Vulcan 09 27,000 56.0 92.9 41Boh/Vulcan 010 32,500 61.5 102.0 45
Conmaco 300E5,Air Hammer 149,600 46.2 76.7 97I.C.E 42‐S, Single‐Acting Diesel 42,000 49.0 81.3 51I.C.E 60S, Single‐Acting Diesel 60,000 53.8 89.2 61
I.C.E I‐46v2, Single‐Acting Diesel 10,700 115.4 191.4 26
APE Model D30‐4237,824 61.2 101.4 4967,274 73.1 121.2 6574,750 30.9 51.2 68
I.C.E I‐30 Diesel Hammer 35,385 58.0 96.3 4771,700 70.2 116.4 67
99%PL k=0.35; n=-1
FL DOTk=0.21; n=-1
10
100
10,000 100,000
Mon
itori
ng d
ista
nce
(ft)
Rate energy of driving hammer (ft-lbf)
99% Prediction level BackCalculation (k=0.35; n=1)
Fl DOT specification
0.25√W
Use the chosen pile driving hammer to determine Vibration Monitoring Distance (based on 50% energy transfer efficiency of hammer and threshold PPV=0.5 in/s)
0.30√W
0.49√W
Current LA DOTD specification
W (ft‐lbs) D (ft)100,000 79.1100,000 94.4100,000 156.5
200
500
200,000
10
100
1000
10,000 100,000
Mon
itori
ng d
ista
nce
(ft)
Rate energy of driving hammer (ft-lbf)
99% prediction level (k=0.211, n=-1);threshold PPV=0.1 in./s
Use the chosen pile driving hammer to determine Vibration Monitoring Distance (based on 50% energy transfer efficiency of hammer and threshold PPV=0.1 in/s) for special conditions
5001.49√W
Conclusions and Recommendations
Vibration Monitoring Distance for LA DOTD
The current LA DOTD specification is too conservative (500 ft)
Use 200-ft for general conditions
Use 500-ft for special cases (loose sand deposits; historic buildings; etc.)
For a given pile driving project with: Designed pile bearing capacity & chosen driving hammer
o Pre‐construction surveyo Estimated Vibration Monitoring Distance (VMD)
Incorporate site specific conditions:o Distances of surrounding buildings from driven pileso Any historic buildings within EVMRo Any building housing sensitive equipment within VMD
Verify adequacy of actual VMD during driving testing piles
Use verified VMD for driving production piles
Modify VMD and/or driving design if actual VMD is not adequate
Implementation Flow-chart
Engineering Mitigation Measures
Pre-poring prior to pile installation Selecting proper hammers to reduce hammers
energy Using cast-in-place piles or non-displacement piles Drilling shaft foundation instead of driven piles
Conclusions and Recommendations
Threshold PPV limits are determined for LA DOTD.
A procedure to determine Pre-construction survey area & Vibration Monitoring Distance is developed.
An updated specification to managing pile-driving induced risk has been developed.
Questions
Acknowledgements
The project is financially supported by the Louisiana Transportation Research Center and Louisiana Department of Transportation and Development (LA DOTD) (09-1GT).
Gavin Gautreau, Dr. Doc Zhang, Dr. Ching Tsai, and other PRC members
Mo Zhang (WPI graduate student) Mark Svinkin (Vibroconsult)
Dynamic settlement (presence of loose sand) Consolidation settlement (presence of soft clay) Threshold shear strain concept
Determining threshold PPV value
Relative density, Dr(%) Description0‐20 Very loose20‐40 Loose40‐60 Medium60‐80 Dense80‐100 Very dense
NHI (2002) Manual on Subsurface Investigations: Geotechnical Site Characterization
Determining threshold PPV value
0.01% >
Compare γ of loose sand to the γt (0.01%).
Determine if loose sand exists based on CPT or SPT results
Dynamic settlement is not a concerned issue.
No Yes
Determining threshold PPV value
0.01% >The shear wave velocities are in the range of 300-500 ft/s for most sands
The threshold PPV values for preventing dynamic settlement are calculated as a range of 0.36-0.6 in/s
Replaced with PPV =k(SD)(-n)
Determining threshold PPV value