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Leads

Hammer

Boom

FoundationPiles

Operating Cab &Machinery House

CS(1

1. Pile Types2. Splicing Piles3. Toe Treatments4. Pile Coating5. Pile Driving Hammers6. Pile Driving Leads7. Methods of Starting Piles8. Pile Testing9. Safety10. Pile Inspection11. Communication and Forms

1. Cast‐in‐Place (CIP) Piles

2. Tapered (CIP) Piles

3. Steel H‐piles

4. Steel Pipe Piles

5. Precast Concrete Piles

6. Timber Piles

Commonly used

Cost effective

Closed end steel pipe, driven, concrete fill

No rock in soil profile

Integral abutment spans < 165’

Conical tips on soft rock or boulders

CIP pile with a taper

Used occasionally

Increased vertical resistance

Decreased uplift resistance

Used for:

Minimal penetration

Additional resistance

Cost effective

Commonly used where:

• Rock >10’ below BOF

• All Integral abutment bridge lengths >165’

• Boulders are present

Slide 1

CS(1 Conklin, Steve (DOT), 12/26/2019

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Similar to CIP, but open‐ended

End plugs up after a bit of driving

Filled with soil or concrete

High axial or lateral capacity applications

Friction or end bearing piles

Used mainly downstate ‐Tappan Zee

Not common upstate ‐ large hammers

Corrosive in salt water

Circular, square, or octagonal cross‐section

Care must be taken to avoid overstress when driving

Corrosive resistance

Marine environments

Difficult to splice

Not common upstate

Consists of a tree trunk driven into the ground

Durable in submerged marine environments, unless organisms that eat the timber are present

Not normally used for bridge foundations anymore, longer spans and higher loads now

Currently used for small projects such as docks

Maximum pile length ~ 60’

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BACKING PLATE ARC GOUGE METHOD

1. FLAT PLATE

2. CONICAL TIPS

3. BUFFALO STAR POINTFLAT TIP AGGRESSIVE TEETH

AND ANGLE TO BITE INTO SLOPING ROCK

NO TREATMENT OR EMBEDDED STINGER FLAT OR POINTED TOES

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• Bitumen

• Epoxy

Coal TarEpoxy Coating

• Air Steam Hammers

• Diesel Hammers (most common upstate)

• Hydraulic Hammers

• Vibratory Hammers

• External power unit• Single‐acting

• Constant rate of 60 bpm• Common stroke of 3 ft

• Double‐acting• Half stroke and half speed of single‐acting

• Must act at prescribed speed or they do not supply correct energy

• Internal power unit

• Single‐acting

• Check stroke and/or blow rate

• Double‐acting

• Bounce chamber pressure must have gauge for inspection and monitoring

• Environmentally friendly

• External power unit

• Single‐acting – state jobs

• Double‐acting – off shore jobs

• Stroke can be easily controlled

• Hammers are closed and ram cannot be seen

• Used to initially drive piles, but not to verify capacity

• External hydraulic power unit

• Eccentrically suspended weights in hammer that turn, creating vibrations

• Record rate of penetration in seconds per ft, frequency, horsepower, pressure

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DieselHammer

Air Steam

Hammer

Hydraulic Hammer

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• Spudding

• Augers

• Jetting

CONTINUOUS FLIGHTAUGER

SINGLE FLIGHTAUGER

Many precast piles have a pipe cast into the pile.

• Dynamic Pile Load Tests

• Static Load Tests Determine Pile Resistance Monitor Pile Stresses Monitor Hammer Performance Determine if Pile has been damaged

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Strain gauges

Accelerometers

300 k pile resistance

Quick Test Loads applied in increments

Constant-Rate-of-Penetration Test Rate at which pile penetrates the soil is controlled

Not Common for Driven Piles

Locations of AccidentsCauses of Accidents in Pile Driving

Protective gear Eye protection

Concrete piles spall, cushions throw out particles, exhaust oil spewed through air, capblock pieces come loose, welding glare, timber piles explode

Position self upwind from & not directly in front of the hammer.

Most dangerous time is between piles finishing paperwork when rig is most active. Leave the area, be alert, or stop operation temporarily if necessary.

Preparation in the Office

Checks in the Field

Documenting in the Field and Office

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Review: Plans Soil Profile BD-138 Form (Pile Driving Data) Pile Driving Criteria

1. Check piles:Off-load piles carefully Check for pile damage Length & Section Steel Thickness Steel Grade Shoe

2. Familiarize yourself with hammer Check Hammer Type & Size

Open ended diesel Air Steam Hydraulic

Check Hammer cushion type, thickness and condition

Inspect Hammer condition Lay hammer down to inspect capblock, cushion

3. Check that Excavation is at grade.

4. Check that pile layout is correct.5. Confirm pile that will placed.6. Check that pile is marked every

foot, and every inch near estimated length.Mark pile every foot

Mark pile Every inch nearEstimated length

7. Identify Proper Pile BatterMinimum LengthPractical RefusalDriving CriteriaPile Set-up

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Minimum Length 10 feet below Bottom of Footing 10 feet below Scour Depth Below a compressible soil layer As specified in Plans

Practical Refusal Typically on Rock 5 blows per ¼ inch (20 bl/in) at

Minimum Required Stroke

Driving CriteriaCriteria used for stopping a pile

1. Blows per foot for 18 inches at minimum required stroke.

2. Within 1 ft of estimated length, driving stops to allow pile to set-up.

3. Dynamic Pile Load Test (DPLT): GEB determines driving criteria after testing in field.

Pile Set-upFine grained soils (Clays, Silts, Fine Sands)Excess pore water pressure or re-moulding of

soil occurs during driving:1. Stop driving for a specified time, allow

pore pressures to dissipate.2. Restrike pile – count blows per inch

Blow count will hopefully increase

1. Note pile penetration & time at start of driving.2. Note blows per ft as driving continues.3. Note Hammer rate of operation in blows per

minute at least every 3 feet. After 10 feet, stop driving & check alignment of pile and

leads.

4. Near estimated length, note blows per inch. Required blow count should be sustained for 18 inches. At refusal (20 bpi), can drive 5 blows per ¼ inch.

Place a good reference for blow counts A board placed on ground

Measure blow rate (easier than measuring stroke) Use 2 people: 1 for blow count, 1 for blow rate

Saximeter a tool for stroke and blow rate Apps are currently being looked into

Mark pile in inches near where driving criteria is expected Record blows per inch and blow rate

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Stroke and/or blow rate are very important for Open Ended Diesel hammers!

The drop height (stroke) determines the energy put into the pile.

The stroke, or blow rate, needs to be combined with the blow count in order to determine if adequate design resistance is achieved.

Higher stroke = lower blow rate, vice versa. If hammer isn’t operating up to rated capacity, piles

won’t achieve the resistance to carry the bridge loads. Possible problems: Poor fuel pump, seals, cushion

If resistance changes from high to low and high again, driving should stop. This could be indicative of pile toe damage.

Note the time that driving stopped. A dynamic pile load test (DPLT) may be needed to

investigate, or the pile may need to be extracted. Note any abrupt changes in penetration rate, or

change in pile alignment or location. Could indicate an obstruction.

Also note if water shows up in CIP casings. Indicative of damage to pile.

Call Main Office Structures sooner, rather than later, if pile driving is not going as expected.

If pile has lost alignment, stop driving. Consult foreman and main office on solutions: 3 possible solutions:

1. Abandon the pile & drive a replacement nearby.2. Pull the pile & start at another location.3. Continue driving & decide on acceptability when

finished. If continued driving is chosen, then the leads and hammer

must be aligned with the new alignment. Otherwise, poor energy transfer and pile damage. Note time that driving resumes.

Record pile length. Note time driving stopped. Survey pile tops. Cover tops of CIP piles to keep out water &

debris. Internally inspect inside of CIPs. Check that rebar cages are correct sizes.

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Pile and Driving Equipment Data (BD 138) Pile Driving Record (MURK 8) Pile Driving Record Summary (MURK 8-1) Welding Procedure Specification (BD 190)

Complete Forms are needed:1. To analyze pile resistance2. Tracking time can be useful in claims

FrontBack

Project Information

Hammer Information

Hammer Cushion Information

Pile Cap Information

Pile Cushion Information

Pile Information

Distribution

Welding Procedures used for:• Splicing Piles• Attaching Toe

Treatments

Materials Used

Filler Metal

Accomplishment of Weld

Weld Progression

Pile MaterialShielded Metal Arc Welding Process (SMAW)

Stick Welding - Manual

Vertical or Horizontal

A5.1E7018 or E8018 rod

Lincoln

Multiple

AC or DCSingle Arc

DC with reverse polarity

Not typically used in the fieldDitto Ditto Ditto

Stingers

250 degreesDescribed in NYSSCM

Not typically used in the field

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Welding Procedure

All 1/8” 120-190 Const-ant

8-12”/min

Sketch for toe protectionSplice details from Plans

Final Blows and Length Information

Hammer Information

Pile Driving Information

Project Information and Pile Driving Location

Pile and Hammer Information

Pile Lengths and Blow Counts

Make sure your piles can support the bridge…

In all conditions

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EICs are encouraged to reach out to RGE/GEB for project specific inspection training.

All of this is covered in the GEB Pile Driving Inspection Manual, GEM‐26