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Piles and Pile Driving
Jackson Tukuafu
Brandon Smith
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Safety First
Pile Driving Terminology
Anchor Pile: pile that is connected to a structure
Butt of pile: the fat end of the pile
Cushion: spreads out impact of the hammer
Cutoff: height you cut your pile after its been driven
Downdrag: condition that adds load to the installed pile
Driving cap/ helmet: protects top of pile while
being driven
Embedment: how much is in the ground
Overdriving: too much driving damages your piles
Penetration: how far it goes in each time you hit it
Pile bent: more than one pile driven in a cluster
Pile-driving shoe: Metal shoe on bottom end to
make it go in better
Soldier pile: holds up an excavation
Tension pile: holds structure down from
being pulled out
Pile Hammers
Types of Hammers
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Drop Hammers
• Single-acting steam or

compressed air
• Double-acting steam or
compressed air
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Differential-acting steam
or compressed air
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Diesel
• Hydraulic-impact and
drivers
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Vibratory drivers
Hammer selection
considerations:
1. Number of piles
2. Character of the soil
3. Location of the project
4. Topography of site
5. Equipment available
6. Pile driving on land or
water
Pile Hammers
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Drop Hammers
–
Only used in remote
areas with less piles
–
Time of completion is
not important

– Productivity
•
4-8 blows/min
–
Not suitable for
concrete piles
Pile Hammers
•
Double-Acting
Hammers
–
“ram” is driven by
compressed air to
steam both when
rising and when
falling
– 95-300
blows/min.
– Lighter ram and
high
Pile Hammers***
•
Single-Acting
Hammers
–
40-60 blows/min
– Sizes vary 7000-
1,800,000 ft-
lb/blow
–

“Ram” is lifted by
steam or
compressed air
and then dropped
Pile Hammers***
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Differential-Acting
–
Uses the
advantages of a
single- and
double-acting
hammers
Pile Hammers
•
Diesel Hammers
–
Open end
•
40-55 blows/min.
–
Close end
• 75-85 blows/min.
–
Used in cohesive
or very dense soils
Pile Hammers***
•
Hydraulic Impact
Hammers

–
Operates on
differential pressure
of hydraulic fluid
– Uses a power unit
– Two types
•
Hydraulic drop
hammer
•
Double-Acting
hammer
Pile Hammer
•
Hydraulic Drivers
–
Press-in hydraulic
pile driver
–
Used for thrusting
and extracting
steel H piles and
steel sheet piles
–
Compact, minimal
noise, and little
vibration
Pile Hammers
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Vibratory Pile

Driver
–
Used when piles
are driven into
water-saturated
non-cohesive soils
– Powered either
electrically or
hydraulically
Pile driving by Jacking
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Used extensively
in underpinning
situations
Jetting Piles
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Use of water to
assist in driving
piles into sand or
fine gravel
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Reduces the
resistance due to
skin friction
Spudding and Preaugering
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Solution to
preexisting
foundations,
previous

construction, hard
overlying soil
strata
Timber Piles
•
Typically 8" tip and 12" butt diameters
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Common lengths 15' to 50'
•
Typically made from pressure treated
southern pine or Douglas fir woods
•
use includes temporary structures, docking
and fender systems, detour bridges and
Bailey bridges
G
Timber Piles, cont’d
Pile Driving Record
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Average pile driving time: 17:22
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Weight of Pile: 1087 lbs.
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Weight of Ram: 900 lbs.
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Rated Energy: 1800 ft*lbs.
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Pile Dimensions: 25’ long, 10” diameter
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Stroke length: 2.0’

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Description of Driving Rig: Pile Master 24-900
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Average # blows for last 12”: 220
Cost Data
Model 24-900 Model 24-2000 Model 24-2500 Model 36-3000
Ram Weight 900 2000 2500 3000
Hammer Weight 2300 4100 4600 6100
Variable Stroke
Minimum 0.5 0.5 0.5
Maximum 2 2 2 1
Energy Rating (Ft*lbs) 3
minimum 450 1000 1250 3000
maximum 1800 4000 5000 9000
blows per minute 15-72 15-72 15-72 15-55
Recommended PSI 125 CFM, 125 psi 185 CFM, 125 psi 185 CFM, 125 psi 250 CFM, 125 psi
Length of hammer: 9 9 10 10
Resistance of Piles to Penetration
Costs
Contract Amount: Cost Plus $6,250,
not to exceed $31,250
Reimbursement for Piling
Bobcat/Auger attachment
Air Compressor
Air Hammer
Labor
Crane Time/Delivery
Concrete
• Precast or cast in place
• Square, cylindrical, octagonal

shapes
• Prone to damage due to
flexural stress
• Drive with heavy ram, large
stroke,
low impact velocity
• Excavate Soil plug to existing
soil elevation
Concrete Piles:
Precast-Prestressed Concrete Piles
•
Displacement piles , the most common in Florida
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Typically used where limestone or dense stratum is <125'
•
Used in corrosive environments
•
Used as friction piles, end bearing piles, and combination of both
•
Voided piles are made to reduce pile weight
•
Voided piles with solid ends provide some protection during driving
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Driven as a group can densify soils in the immediate area
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Large, heavy, hard to cut/splice
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High transportation costs