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ACIP and DD Pile Case HistoriesPresented by:
Morgan NeSmithChief Geotechnical Engineer
To
DFI Seminar
New York NY
07 November 2013
• Scope of Presentation Drilled Displacement Piles in NYC
Continuously Flighted Piles in NYC
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Initial use of ACIP Piles in NYCLate 1970s
• Alternative to driven piles where vibrations from driven piles had damaged existing structures.
• Loss-of-ground problems documented.
• Application generally limited to vibration-sensitive projects.
• “Uncased concrete piles” not addressed in NYC Building Code. Use requires submission to Building Department.
• Augers advanced by power units that developed +- 30,000 ft-lbs
• ASTM C-33 sand used in grout mixes.
• Higher volume, more powerful pumps are available.
• Redi-mix grout common.
• Original patent for ACIP piles expires. New installers enter the market.
STATE OF THE ACIP INDUSTRYLate 1970s
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• First application was on a project where the use of driven piles was restricted.
• Like conventional ACIP piles, low noise, very low vibration.
• No soil transport = no loss-of-ground issues.
• Drastic reduction in spoils.
• Higher unit shaft and toe components in sands.
Initial use of DD Piles in NYC2002
Displacement Pile Tool
Stem becomes progressively larger, terminating in the displacing element
+- 3 feet, regular flighting
Reverse flighting Displacing element. Same diameter as the flighting below
Stem, smaller than flighting
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Installation Platform
TO GROUT PUMP
REAL-TIME DISPLAY OF DEPTH, TORQUE,
AND GROUT PRESSURE
PRESSURE SENSOR
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Installation
E
Grout “overpressure” is measured at the top of the tools, which may be 60 feet to 90 feet above the tip. Overpressure range for liftoff and shaft casting is 10 to 20 psi.
Pressure at the tip includes the overpressure plus the fluid head of grout in the stem.
Augers filled with soil, and the displacing element, act as a packer to confine the grout below the tool.
Any soil in the annular space around the stem is capture by reverse flighting and displaced into the sides of the hole.
Pressure Sensor
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BASIC INSTALLATION
CHART
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Power Plant - Nassau County
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GENERATOR
0
10
20
30
40
50
60
0 50 100 150 200
qc, tsf
De
pth
, ft
TURBINE
0
10
20
30
40
50
60
0 50 100 150 200
qc, tsf
De
pth
, ft
WEST EDGE OF STACK
0
10
20
30
40
50
60
0 50 100 150 200
qc, tsf
De
pth
, ft
Power Plant - Nassau County
FINE GRAINED ORGANIC
FILL
SAND
GENERATOR
0
10
20
30
40
50
60
0 50 100 150 200
qc, tsf
De
pth
, ft
TURBINE
0
10
20
30
40
50
60
0 50 100 150 200
qc, tsf
De
pth
, ft
WEST EDGE OF STACK
0
10
20
30
40
50
60
0 50 100 150 200
qc, tsf
De
pth
, ft
Power Plant - Nassau County
FINE GRAINED ORGANIC
FILL
SAND
22-ft x 16-in DD pile for 50 tons
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Power Plant - Nassau County
Riverdale Plaza - Bronx
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Riverdale Plaza - Bronx
CPT-B.4-8, Near Test Pile 1
0
10
20
30
40
50
0 100 200 300
qc, tsfD
epth
, ft.
Soil Type Number
0
10
20
30
40
50
0 2 4 6 8 10
Dep
th, f
t.
FILL
FINE GRAINED
SAND
Cobbles
Riverdale Plaza - Bronx
CPT-B.4-8, Near Test Pile 1
0
10
20
30
40
50
0 100 200 300
qc, tsf
Dep
th, f
t.
Soil Type Number
0
10
20
30
40
50
0 2 4 6 8 10
Dep
th, f
t.
FILL
FINE GRAINED
SAND
Cobbles
14-in dia. X 30 ft for 60 tons
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Test Pile Installation Record
Torque
Depth
Grout Pressure
Riverdale Plaza - Bronx
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Coney Island Hospital - Brooklyn
Coney Island Hospital - Brooklyn
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Cone Tip Resistance vs Depth, Coney Island Hospital
0
10
20
30
40
50
60
0 50 100 150 200
Cone Tip Resistance (qc), tsf
Dep
th, f
t
Coney Island Hospital - Brooklyn
SAND
FILL
Cone Tip Resistance vs Depth, Coney Island Hospital
0
10
20
30
40
50
60
0 50 100 150 200
Cone Tip Resistance (qc), tsf
Dep
th, f
t
Coney Island Hospital - Brooklyn
SAND
FILL
16-in dia. X 44 ft for 80 tons
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Coney Island Hospital - Brooklyn
Coney Island Hospital - Brooklyn
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Lowes - Brooklyn
Boring B-8, Near Test Pile 2
0
10
20
30
40
50
60
0 10 20 30 40 50
SPT "N", bpf
De
pth
, ft
Boring B-1S, Near Test Pile 1
0
10
20
30
40
50
60
0 10 20 30 40 50
SPT "N", bpf
De
pth
, ft
Lowes - Brooklyn
FINE GRAINED ORGANIC
FILL
SAND
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Boring B-8, Near Test Pile 2
0
10
20
30
40
50
60
0 10 20 30 40 50
SPT "N", bpf
De
pth
, ft
Boring B-1S, Near Test Pile 1
0
10
20
30
40
50
60
0 10 20 30 40 50
SPT "N", bpf
De
pth
, ft
Lowes - Brooklyn
FINE GRAINED ORGANIC
FILL
SAND
12-in dia. X 35 ft for 30 tons
Lowes – Brooklyn
Load Displacement 1, Lowes, Brooklyn 12" Diameter, 35' Berkel Displacement Pile, 30-ton Compression
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
0 10 20 30 40 50 60 70 80 90
Load, tons
Dis
pla
cem
en
t, in
ch
es
TEST DATA HYPERBOLIC MODEL
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Lowes - BrooklynLoad Displacement 2, Lowes, Brooklyn
12" Diameter, 35' Berkel Displacement Pile, 30-ton Compression
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
0 10 20 30 40 50 60 70 80
Load, tons
Dis
pla
cem
ent,
inc
hes
TEST DATA HYPERBOLIC MODEL
• Areas of glacial and alluvial deposits (where DD piles may be feasible) occur in all five boroughs and Long Island.
• In some of the glacial deposits (clean, angular sands and gravels) shaft and toe resistances are among the highest developed with DD piles.
• Zones of cobbles, boulders and dense sands limit application or capacity
• Current design methodology is applicable under NYC Building Code
• Application is a function of matching system characteristics, subsurface conditions and working capacity
Application of DD Piles in New York City
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What about flighted piles?Queens Approach - Bronx Whitestone Bridge
Queens Approach - Bronx Whitestone Bridge
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4Q-R 5Q-R
Queens Approach - Bronx Whitestone Bridge
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