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Pile Driving TerminologyAnchor 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 pil

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

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

• 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

• 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

• Vibratory Pile

Driver

– Used when piles

are driven into

water-saturated

non-cohesive soils – Powered either

electrically or

hydraulically

Pile driving by Jacking

• Used extensively

in underpinning

situations

Jetting Piles

• Use of water to assist in driving piles into sand or fine gravel

• Reduces the

resistance due to skin friction

Spudding and Preaugering

Timber Piles

• Typically 8" tip and 12" butt diameters

• 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

•Average pile driving time: 17:22

•Description of Driving Rig: Pile Master 24-900

•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

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

Contract Amount: Cost Plus $6,250,

not to exceed $31,250Reimbursement for Piling

Bobcat/Auger attachment Air Compressor

Air Hammer

Labor

Crane Time/Delivery

• Precast or cast in place

• Square, cylindrical, octagonal

low impact velocity

• Excavate Soil plug to existing

soil elevation

Concrete Piles: Precast-Prestressed Concrete Piles

•Displacement piles , the most common in Florida

•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

•Driven as a group can densify soils in the immediate area

•Large, heavy, hard to cut/splice

•High transportation costs

Concrete Piles: Cast in Place with Shells (cased)

Cast in place, cont’d: Cast in situ pile (Franki technique)

Advantages:

• Fast

• Economical,

• Reinforcement of pile shaft can be increased at top of pile

• Effective method of making an enlarged base

• Allowable pile loads can be very high, up to 2500 kN

Concrete Piles:

Augered Cast in Place (uncased)

•Drilling with auger

• Inject grout through the auger • Reinforcing is inserted before it cures• 3000-5000 PSI

Concrete Piles: Bent/Pier Piles

•Pile tops generally are at or below

existing grade.

•piles are tied together with a pile cap

(footing)

•column is constructed from the pile cap

up to the required beam seat elevation

•finished for connection to the structure.

•piles rise above the ground surface

to a specified elevation

• piles are tied together with a bent cap.

• Greater depth

• H-sections, hollow box/tubular

secions, or pipes

• More expensive per length of pile

• Higher load-carrying capacity can reduce driving costs

• Little displacement=high transfer

of energy to bottom of pile

Steel Piles:

H-Piles

• Are non-displacement piles

• Not as common as concrete piles

• Typically used where pile lengths over 125‘ are needed or extremely variable subsurface conditions exist

• Ease of splicing is big advantage

• Non displacement piles are often used where a

large number of piles are needed in a small area,

such as under a Bascule bridge pier

Steel Piles: Open Ended Pipe Piles

•The least common of the typical piles

•Are hollow pre-stressed concrete pipes manufactured to project needs

•Used when project is accessible by barge

•Used in corrosive environments

•Can be used as both end-bearing and friction piles

•Displacement piles, following installation can be filled with concrete

or other materials

•Very heavy and requires larger than typical barges, cranes and

driving equipment

Advantages of Composite Pilings:

• High strength-to-weight ratio

•Directional strength

•Corrosion & weather resistance

•Dimensional stability

•Low thermal conductivity

•Low coefficient of thermal expansion

•Non-magnetic

•High impact strength

•Low maintenance

•Long term durability

•Tailored surface finish

•light weight

The Super Kong

“You can’t build up if you don’t build down.”

“You can’t build up if you don’t build down.”

Sheet Piles: Material

Sheet Piles: Material

Sheet Piles: Materials

• Steel Sheet Piles

– Two common types

found in the U.S

• Flat and Z section sheets

Sheet Piles: Plastic

• it does not rust or rot;

• no risk of sparking;

• maintains its original

appearance over time,

• not affected by salt water;

• resistant to marine borers

and rodent attack;

• easily cut or bored;

• maintenance free;

• lighter to handle;

• available in a variety of

colours

Questions