701DRIVEN PILING

701.01Description

This work shall consist of furnishing and driving foundation piles of the type and dimensions specified including cutting of f or building up foundation piles when required. This work shall also consist of providing test piles and performing loading tests when required. Piling shall be installed at the location and to the tip elevation, the penetration depth, and nominal driving re sistance shown on the plans in accordance with 105.03.

MATERIALS

701.02Materials

Materials shall be in acco rdance with the following:

B Borrow ..................................................................... 904.06* Bentonite Grout ........................................................... 913.06 Conical Pile Tips ......................................................... 915.01(a)2 End Plates .................................................................... 915.01(a)1 20 Epoxy Coating fo r Piles ............................................... 915.01(d) Pile Sh oes .................................................................... 915.03 Reinforcing Bars .......................................................... 910.01 Steel H Piles ................................................................ 915.02 Steel Pipe Piles ............................................................ 915.01 Timber Piling, Treated ................................................. 911.02(c) Timber Piling, Untreated ............................................. 911.01(e)

* B borrow consisting of ACBF or GBF shall not be used.

Unless otherwise specified, reinforcing bars may be either plain or epoxy coated.

Steel pipe piles shall consist of a steel pipe which is driven into place and filled with class A concrete.

The Contractor may furnish and drive steel pipe piles with thicker walls than specified.

Treated and untreated timber piles shall be strapped with at least three straps: one approximately 18 in. from the butt, one approximately 24 in. from the butt, and one 40 approximately 12 in. from the tip. Additional straps shall be provided at approximately 15 ft centers between the butt and tip. Strapping shall encircle the pile once and be tensioned as tightly as possible. Straps shall be 1 1/4 in. wide, 0.031 in. thick, cold rolled, fully heat treated, high tensile strapping, painted and waxed, with breaking 701.02

strength of 5,500 lb. The strap shall be crimped with a notch type sealer to furnish a joint yielding 80% of the strap tensile stre ngth. Treated timber piles shall be strapped after treatment.

701.03Handling of Epoxy Coated Piles

Epoxy coated piles shall be protected at all times from damage to the epoxy 50 coating. Damage to epoxy coated piles shall be repaired in accordance with 915.01(d). Epoxy coated piles will be rejected if the total area of repair to the coating exceeds 2% of the total coated surface area.

CONSTRUCTION REQUIREMENTS

701.04Equipment for Driving Piles

All pile driving equipment, including the pile driving hammer, hammer cushion, 60 helmet or pile drive head, pile cushion, and other appurtenances furnished by the Contractor shall be in working condition and approved in writing by the Engineer prior to delivery of the pile driving equipment to the job site. All pile driving equipment shall be sized such that the piles can be driven to the length required without damage. Approval of pile driving equipment does not relieve the Contractor of the responsibility to drive piles, free of damage, to the required nominal driving resistance and, if specified, the minimum tip elevation shown on the plans. Pile driving equipment will be subject to satisfactory performance during production.

The Contractor shall submit a completed pile and driving equipment data form to 70 the Engineer at least 15 calendar days prior to driving piles. The pile and driving equipment data form is available on the Department’s website. The Contractor will be notified of the acceptance of the proposed pile driving system within 15 calendar days of the receipt of the pile and driving equipment data fo rm. Acceptance of pile and driving equipment does not relieve the Contractor of the responsibility to provide equipment suitable for driving the specified piling to the required bearing without damage.

If the method of pile driving approval is in accordance with the dynamic formula shown in 701.05(a) the dynamic formula method will be used to determine if the pile 80 driving equipment is acceptable for use. To be considered for approval, the proposed driving system shall obtain the nominal driving resistance between the specified blow count range of 30 and 120 blows per foot.

If the nominal driving resistance is to be determined by dynamic pile load test in accordance with 701.05(b) or static load test in accordance with 701.05(c), the Engineer will use the wave equation analysis method for driving system approval. To be approved, the proposed driving system shall obtain the nominal driving resistance between the specified blow count range of 30 and 120 blows per foot, and shall maintain driving stresses below the specified driving stress limits for the pile type 90 701.03

being driven. If wave equation predicted driving stresses are greater than specification limits or the wave equation blow count for the nominal driving resistance is outside the specified blow count range, the Contractor shall modify or replace the proposed equipment until subsequent wave equation analyses indicate the piles can be driven to the nominal driving resistance within the allowable blow count range and within driving stress limits.

If the driving system requires revision, the Contractor will be notified of the acceptance of the revised driving system with in seven calendar days of receipt of a revised pile and driving equipment data form. 100

The Contractor shall use the approved pile driving system. No changes shall be made without prior written approval from th e Engineer, with the exception that the concrete pile cushion thickness may be increased to control driving stresses. A change in the pile driving system will only be considered after the Contractor has submitted a new pile and driving equipment data form. The Contractor will be notified of the acceptance of a proposed change in drivi ng equipment within three work days of receipt of the pile and driving equipment data form. If the Engineer determines the Contractor’s hammer is not functioning properly and is unable to drive the piles to the required penetration depth or nominal driving resistance, the hammer shall be removed 110 from service.

If the dynamic formula method is used, the energy of the pile driving equipment shall be rated by the manufacturer at or above the appropriate minimum manufacturer’s rated hammer energy for the corresponding nominal driving resistance as shown in the table below. The table below will be used as the basis of approval of pile driving equipment for the dynamic formula method.

DYNAMIC FORMULA METHOD Minimum Pile Hammer Requirements Nominal Driving Resistance Minimum Manufacturer’s Rated Energy kips ft·lb ” 12,000 181 - 300 21,000 301 - 400 28,800 > 400 Wave Equation Analysis required

The minimum rated energies do not account for losses and inef ficiencies in the pile driving system. If the hammer selected cannot satisfy all the criteria, a wave equation analysis shall be submitted by the Contractor for approval.

701.04

For the pile driving equipment to be acceptable, the driving stresses predicted by the wave equation analysis shall not exceed the values where pile damage impends. These limiting values shall be calculated as follows:

steel piles = 0.9F y.

concrete piles = (0.85f’c - fpe), where fpe is the effective prestress value.

concrete piles = ටf c ' + fpe

, where f’c and fpe are expressed in psi.

approved working drawings.

exceed 3Fco, where Fco is the base resistance of wood in compression parallel to the grain, in psi.

Piles may be driven with air, steam , diesel, or hydraulic hammers. Gravity hammers, vibratory hammers, and other pile driving methods shall be used only if 150 specified or approved in writing by the Engineer.

Gravity or drop hammers shall be used to drive timber piles only. The ram shall have a weight of between 2,000 and 3,500 lb . The height of drop shall not exceed 12 ft. The weight of gravity hammers shall not be less than the combined weight of the helmet and pile. All gravity hammers sh all be equipped with hammer guides and helmet to ensure concentric impact on the drive head.

The plant and equipment furnished for steam and air hammers shall have sufficient capacity to maintain, under working conditions, the volume and pressure specified by the manufacturer of the hammer. The hose connecting the air compressor to the hammer shall be at least the mi nimum size recommended by the manufacturer. The plant and equipment shall be equipped with accurate chamber pressure gauges which are easily accessible to th e Engineer. If wave equation analysis is not used for pre-approval, the weight of the striking parts of air and steam hammers shall be equal to or greater than one-third the combined weights of the drive head and pile being 701.04

driven. The striking parts shall not weigh less than 2,800 lb. Proximity switches and an electronic readout device shall be provided prior to driving piling. 170

Open-end or single acting diesel hammers shall be equipped with a device such as graduated rings or grooves on the ram to enable the Engineer to visually determine hammer stroke at all times during pile driving operations. The Contractor shall provide the Engineer a chart from the hammer manufacturer equating stroke, blows per minute, and potential energy for the approved open-end diesel hammer. The Contractor shall also provide and maintain, in working order, an approved device that automatically measures and displays the ram stroke for open-end diesel hammers.

Closed-end double acting diesel hammers shall be equipped with an accurate bounce chamber pressure gauge, easily accessible to the Engineer. The Contractor shall provide the Engineer a calibrated chart equating bounce chamber pressure to either equivalent energy or stroke for the closed-end diesel hammer to be used. Calibration of actual hammer performance shall be performed no more than 90 days prior to the beginning of the work.

Under working conditions, the power plant shall have sufficient capacity to maintain the volume and pressure for the hydraulic hammer as specified by the 190 manufacturer. Hydraulic hammers shall also be equipped with a controlled variable stroke system and a readout device to measure ram energy. The plant and equipment shall be equipped with accurate pressure and velocity gauges and an energy readout device which are easily accessible to the Engineer.

Except for pile lengths which have been evaluated from load test piles, the nominal driving resistance of the piles driven with vibratory hammers shall be verified

by redriving the first pile driven in each group of 10 or fewer piles with an impact

hammer of suitable energy to measure the nominal driving resistance before driving200

the remaining piles in the group. All piles which rely on point bearing capacity shall

be redriven with an impact hammer.

Pile driving aids such as jets and followers, shall not be used unless specified or

approved in writing by the Engineer. If specified or approved, pile driving aids shall

be used for installing production piles only after the minimum pile tip elevation is

established by means of load testing or indicator test piles conventionally driven in

accordance with 701.05. The Contractor shall perform all extra load tests or extra work

required to drive indicator test piles as determined by the Engineer.210

All impact pile driving equipment, except gravity hammers, shall be equipped

with a suitable thickness of hammer cushion material to prevent damage to the hammer

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602

or pile and to ensure uniform driving behavior. Impact hammers designed such that a

hammer cushion is not required are excluded from this requirement. Hammer cushions

shall be made of durable, manufactured materials, provided in accordance with the

hammer manufacturer’s guidelines. Wood, wire rope, or asbestos hammer cushions

shall not be used. A striker plate, as recommended by the hammer manufacturer, shall

be placed on the hammer cushion to ensure uniform compression of the cushion220

material. The condition of the hammer cushion shall be checked with the Engineer

when beginning pile driving at each structure or after each 100 h of pile driving,

whichever is less. A hammer cushion whose thickness has been reduced to less than

75% of the original thickness shall be replaced.

Piles driven with impact hammers shall have an adequate helmet that adequately

distributes the hammer blow uniformly and concentrically to the pile head. The helmet

shall be axially aligned with the hammer and the pile shall be guided by the leads and

not be free-swinging. The helmet shall fit around the pile head and prevent transfer of230

torsional forces during driving while maintaining proper alignment of hammer and

pile.

For steel and timber piling, the pile heads shall be cut squarely. For timber piles,

the least inside helmet horizontal dimension or hammer base horizontal dimension

shall not exceed the pile head diameter by more than 2 in. If the timber pile diameter

slightly exceeds the least helmet or hammer base dimension, the pile head shall be

trimmed to fit the helmet.

A helmet as recommended by the manufacturer shall be provided to hold the axis240

of the pile in line with the axis of the hammer. The pile head shall be plane and

perpendicular to the longitudinal axis of the pile to prevent eccentric impacts from the

drive head.

The heads of concrete piles shall each be protected with a pile cushion made of

plywood, hardwood, or composite plywood and hardwood materials. The use of

manufactured pile cushion materials shall be by the hammer manufacturer’s

recommendation. The pile cushion dimensions shall equal or exceed the cross-

sectional area of the pile top, and shall be sized to fit the dimensions of the pile cap.250

The minimum pile cushion thickness placed on the pile head prior to driving shall be

either as recommended by wave equation analysis or not less than 4 in. if the dynamic

formula is used. A new pile cushion shall be provided for each pile. The pile cushion

shall be replaced if, during the driving of the pile, the cushion is either compressed

more than one-half the original thickness or begins to smolder or burn. Pile cushions

shall be protected from weather and kept dry prior to use. Pile cushions shall not be

soaked in liquid unless approved by the Engineer.

A used pile cushion in acceptable condition shall be used for restrike tests. The

used pile cushion shall be the same pile cushion from the end of initial driving on that260

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603

pile unless the condition of that pile cushion is no longer within specification limits.

If the original pile cushion is not within specification limits, a used cushion of similar

thickness as the end of drive pile cushion shall be used.

Piles shall be supported in line and position with leads while being driven. Pile

driver leads shall be constructed in a manner that affords freedom of movement of the

hammer while maintaining alignment of the hammer and the pile to ensure concentric

impact for each blow. Leads may be either fixed or swinging type. Swinging leads,

when used, shall be fitted with a pile gate at the bottom of the leads. The leads shall270

be adequately embedded in the ground, or the pile shall be constrained in a structural

frame such as a template to maintain alignment. The leads shall be of sufficient length

to make the use of a follower unnecessary and shall be designed as to enable proper

alignment of battered piles.

Followers shall only be used if specified or approved in writing by the Engineer.

If a follower is allowed, the first pile in each bent and every tenth pile driven thereafter

shall be driven full length without a follower, to verify that adequate pile length is

being attained to develop the nominal driving resistance. The follower and pile shall280

be held and maintained in equal and proper alignment during driving. The follower

shall be of such material and dimensions to enable the piles to be driven to the required

penetration depth determined necessary from the driving of the full length piles.

The final position and alignment of the first two piles installed with followers in

each substructure unit shall not exceed more than 3 in. from the locations shown on

the plans before additional piles are installed.

Jetting shall only be allowed if specified or approved in writing by the Engineer.290

The Contractor shall determine the number of jets and the volume and pressure of

water at the jet nozzles necessary to freely erode the material adjacent to the pile

without affecting the lateral stability of the final in-place pile. The Contractor shall be

responsible for all damage to the site caused by unapproved or improper jetting

operations. If jetting is specified, the jetting plant shall have sufficient capacity to

enable installation to the required elevation, location, and alignment in accordance

with 701.09(b). Unless otherwise directed, external jet pipes shall be removed once

the pile tip is 5 ft above the prescribed tip elevation, depending on soil conditions. The

pile shall then be driven to the nominal driving resistance with an impact hammer. The

Contractor shall provide suitable sediment control measures for jet water in300

accordance with the specifications. Where practical, all piles in a pile group shall be

jetted to the required penetration depth before beginning pile driving. Where large pile

groups or pile spacing and batter make this impractical, restrike tests on a select

number of previously driven piles shall be performed to check nominal driving

resistance after jetting operations are completed.

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604

Upon completion of driving a jetted pile, all voids around the pile shall be filled

with B borrow and saturated with water.

Where timber piles are used, collars, bands, or other devices shall be provided to

protect piles against splitting and brooming.

Pile shoes shall be used when specified. End plates or conical pile tips shall be

used on pipe piles. Steel pile shoes shall be used on H piles if specified.

If shoes are required on timber piles, the tips of timber piles shall conform to the

approved steel shoes to ensure a firm uniform contact and prevent local stresses

concentrations in the timber.320

701.05Nominal Driving Resistance of a Driven Pile

The Engineer will use one of the following methods as specified to determine the

nominal driving resistance of a driven pile.

The nominal driving resistance will be determined by means of a dynamic

formula. Piles shall be driven to the penetration depth necessary to obtain the nominal

driving resistance. The nominal driving resistance, as shown on the plans, can be

calculated from the formula as follows:330

Rndr = 1.75ξE x (log 10N) – 100

where:

Rndr = nominal driving resistance in kips

E = manufacturer’s rated energy in foot·pounds at the field observed

ram stroke and not reduced for efficiency

log 10N = logarithm to the base 10 of the quantity 10 multiplied by N,

where N is the number of hammer blows per 1 in. at final

penetration.

An indicator test pile shall be the first pile driven at each bent and pier and shall

be driven to the plan tip elevation or to the nominal driving resistance whichever

occurs first. All indicator test piles shall be driven with impact hammers unless

otherwise directed. The length of indicator test piles shall be greater than the estimated

length of production piles to provide for variation in soil conditions. Precast concrete340

and treated timber test piles shall be a minimum of 10 ft longer than the estimated

length of piling shown on the plans. Steel piles shall be provided such that additional

10 ft of driving will not require an additional splice.

The driving equipment used for driving indicator test piles shall be identical to

that proposed for use on the production piling and shall be subject to approval. The

701.05

605

Contractor shall excavate the ground at each indicator test pile location to the elevation

of the bottom of the footing before the pile is driven, unless otherwise shown on the

plans.

350

To assess the effects of relaxation and setup, each indicator test pile shall be

restruck after the number of hours specified unless otherwise approved. The hammer

shall be warmed up before driving begins by applying at least 20 blows to another

fixed object. The maximum amount of penetration required during restrike shall be 3

in., or the total number of hammer blows shall be 20, whichever occurs first. If the

indicator test pile does attain the nominal driving resistance upon restriking, the

penetration resistance attained during initial driving shall be used to establish the

adequacy of production piles. If the nominal driving resistance is not attained upon

restriking, the Contractor shall redrive the indicator test pile until it achieves the

nominal driving resistance and repeat the restrike procedure described above. If the360

nominal driving resistance is still not obtained, pile driving shall stop immediately and

the Office of Geotechnical Services shall be notified.

A record of driving indicator test piles, which includes the number of hammer

blows per 1 ft for the entire driven length, the as-driven length, cutoff elevation,

penetration, and all other pertinent information will be kept by the Engineer. The

penetration resistance at various hammer strokes versus nominal driving resistance

relationship will be determined based on the driving of representative indicator test

piles.

370

If indicator piles are not shown on the plans, all piles shall be driven to the nominal

driving resistance and restriking is not required.

Dynamic monitoring will be performed for the purpose of obtaining the nominal

driving resistance, pile driving stresses, pile integrity, and pile driving system

performance. Dynamic monitoring will be conducted by PDA in accordance with

ASTM D4945. PDA will be performed on the first pile driven. The length of the pile

used in the dynamic pile load test shall be a minimum of 10 ft greater than the

estimated length of production piles in order to provide for variation in soil conditions.380

The Contractor shall assist the Department in obtaining dynamic measurements with

the PDA during initial pile driving and during pile restrikes. If a static load test is

required, the dynamic pile load test shall be performed on the same pile as the pile

used in the static load test. The restrike for the dynamic pile load test on a static load

test pile shall be performed within 48 h of completion of the static load test.

The Contractor shall notify the Engineer at least seven calendar days before the

scheduled date of driving piles to be monitored by PDA. The Contractor shall confirm

the driving date three calendar days prior to the scheduled driving date. The Contractor390

shall indicate at which foundation production pile driving is to begin. The Engineer

will provide final driving criteria for the indicated foundation first.

701.05

606

The Contractor shall make the steel piles available so that the Engineer can

predrill the required instrument attachment holes prior to the Contractor placing the

pile in the leads. Each pile to be tested shall be instrumented with force and

acceleration transducers provided by the Department. The Contractor shall install the

transducers before striking the pile. The pile driving may have to be temporarily

interrupted for the transducers to be adjusted or replaced, or for the monitoring results400

assessed.

Prior to placement in the leads, the Contractor shall make each designated

concrete or timber pile available for taking of wave speed measurements and for

predrilling the required instrument attachment holes. When wave speed measurements

are made, the piling shall be in a horizontal position and not in contact with other

piling. Predriving wave speed measurements will not be required for steel piles. The

Contractor shall mount the instruments near the head of the pile after the pile is placed

in the leads.

410

The Contractor shall drive the test pile to the minimum tip elevation and to the

penetration depth at which the dynamic test equipment indicates that the nominal

driving resistance shown on the plans and in accordance with 701.04(a) has been

achieved. The Contractor may reduce the driving energy transmitted to the pile by

using additional cushions or reducing the energy output of the hammer in order to

maintain stresses below the values shown in 701.04(a)1. If non-axial driving is

indicated by the dynamic test equipment measurements, the Contractor shall

immediately realign the hammer system. Upon determination by the Engineer that

valid data has been secured, the Contractor shall assist the Engineer with the removal

of the instrumentation from the pile.420

The Contractor shall wait the specified minimum time period prior to the

restriking of a dynamic load test pile. The Contractor shall assist the Engineer with

reattachment of dynamic test instruments. The hammer shall be warmed up before

restriking begins by applying at least 20 blows to another pile or other fixed object.

The maximum amount of penetration required during restrike will be 3 in., or the total

number of hammer blows will be 20, whichever occurs first. If the pile does not

achieve the required nominal driving resistance during restrike, the Engineer will

either accept the tip elevation or specify additional pile penetration and testing.430

Once the restrike test for the test pile is complete, the Engineer will run CAPWAP

analyses and will provide the final driving criteria within two business days of the

restrike test. Production piles driven prior to receipt of the final driving criteria shall

be done at the Contractor’s risk. Final driving criteria for additional structures will be

provided within two business days of the restrike test or, when multiple test piles are

restruck the same day, at a rate of one substructure location per business day in the

order requested by the Contractor.

701.05

607

The Contractor shall perform the PDA in accordance with ASTM D4945. The

firm conducting the PDA shall have at least one geotechnical engineer who shall have

achieved one of the following certification levels: intermediate, advanced, master, or

expert, within the last three years through the Dynamic Measurement and Analyses

Proficiency Test conducted by Pile Dynamics, Inc., and the Pile Driving Contractors

Association. An engineer with a lower certification level can provide services so long

as this individual is under the direct supervision of an engineer with intermediate

certification level or higher. The CAPWAP shall be utilized to determine the as-built

pile capacity from the PDA data. The first pile driven for each substructure unit shall

be a PDA test pile. The pile driving criteria with the PDA and CAPWAP results shall450

be submitted to the Department’s Office of Geotechnical Services for approval.

A static load test shall be conducted on a non-production test pile at the location

shown on the plans. The test pile axial deflection in compression shall be verified by

performing actual loading tests of the designated static load test pile in accordance

with ASTM D1143, Quick Load Test Method, with loads applied by hydraulic jack.

The test shall be continued until either plunging failure is achieved or the capacity of

the loading system is reached. The nominal pile resistance will be determined from the

settlement versus load curve generated by the incremental loading in accordance with460

The top elevation of all test piles shall be determined immediately after driving

and again just before load testing to check for heave. A pile which heaves more than

1/4 in. shall be redriven, or jacked, to the original elevation prior to testing. The

Contractor shall wait 36 h between the driving of a load test pile and the

commencement of the load testing unless otherwise specified.

The Contractor shall provide complete protection at all times for the pile,

supports, and reference beam from wind, direct sunlight, frost action, or other470

disturbances. The Contractor shall maintain an air temperature in the immediate

vicinity of the test pile and reference beam of not less than 50°F and shall provide

adequate lighting for the duration of the test.

No production piles shall be driven until completion of the static pile load test

unless approved by the Engineer. Reaction piles shall be driven prior to driving the

static load test pile.

The Contractor shall furnish and construct a suitable reaction frame or load480

platform to provide a load on the pile having a capacity of 2,000 kips or 150% of the

nominal driving resistance, whichever is less. A minimum of seven days prior to

driving the static load test pile or construction of the reaction frame or load platform,

the Contractor shall submit, for review and approval, detailed working drawings to

701.05

608

scale for the reaction frame or load platform and loading apparatus including the

distances between the load test pile and all reaction piles and reference beam supports.

The submittal shall also include a proposed load test and reaction pile driving

sequence, a scaled profile drawing of the loading apparatus detailing the ground

surface elevation, the pile cutoff elevation, the dimensions and locations of all bearing

plates, the jack, the load cell, the spherical bearing plate, and the reaction beam or490

platform.

Working drawings for the reaction frame and loading apparatus shall be submitted

in accordance with 105.02. The submittal shall include calibration certifications for

the hydraulic jacks, load cell, pressure gauges, and hydraulic pumps conducted within

30 days of the load test. If required by the Engineer, the jack, load cell, and pressure

gauge shall be recalibrated after the load test. The loading apparatus shall be

constructed to allow the various increments of the load to be placed gradually, without

causing vibration to the test pile. If the approved method requires the use of tension or

reaction piles, the reaction piles, if feasible, shall be of the same type and dimensions500

as the production piles and shall be driven in the location of permanent piles. Reaction

piles that are the same type and dimensions as the production piles and are driven in

the location of permanent piles will be considered permanent piles.

Timber or tapered piles installed in permanent locations shall not be used as

tension piles. The primary method of determining the applied load shall be from a

calibrated load cell. Incremental loads of 5% of the nominal driving resistance shall

be placed on the pile at 5-minute intervals until continuous jacking is required to

maintain the incremental load or the capacity of the load frame is reached. Support for

the load test plates, jack, and ancillary devices shall be provided to prevent them from510

falling in the event of a release of load due to hydraulic failure, test pile failure, or

other cause.

The Contractor shall furnish the hydraulic pump, load cell, spherical bearing plate,

and two reference beams. Each reference beam shall be a W or M section, of minimum

length of 20 ft, and a weight of 5 to 20 lb/ft unless otherwise approved. The Engineer

will conduct the static load test and will provide the gauges to measure movement of

the test pile. The Contractor shall provide all assistance necessary to perform the static

load test. The Contractor shall furnish and install telltale rods encased in a lubricated

pipe in the test pile prior to the static load test.520

If the nominal pile resistance of a pile from the load settlement curve does not

equal or exceed the nominal driving resistance shown on the plans, the Contractor shall

redrive the pile to an adequate nominal driving resistance. The increase in nominal

driving resistance will be determined by PDA. The pile shall be load tested again after

the appropriate waiting period. Load tests shall be repeated as many times as necessary

until the pile carries the required load. The pile axial resistance will be determined

from the test data in accordance with the Davisson Method as specified in the

AASHTO LRFD Bridge Design Specifications.

530

701.05

609

Hydraulic jacks and pressure gauges shall be used for the superimposed load. The

jacks, pressure gauges, load cell, and hydraulic pumps shall be calibrated with each

other within the last 30 days by an independent laboratory. When a jack, pressure

gauge, load cell, and hydraulic pump are calibrated, they shall be calibrated and used

as a unit. All calibration checks shall be within 5% of the applied load if calibrated as

a unit. Changing one of the four components shall require recalibration prior to use.

Pressure gauges shall be a minimum of 4 1/2 in. in diameter with gradations in

accordance with ASTM D1143. Hydraulic jacks shall have a nominal load capacity

exceeding the maximum anticipated jack load by at least 20%. The jack, pump, any540

hoses, pipes, fittings, gauges, or transducers used shall be rated to a safe pressure

corresponding to the nominal jack capacity. The Contractor shall provide copies of the

most recent calibration certification a minimum of five days prior to the static load

test.

On completion of the static load test, a test pile or anchor pile which is not a part

of the finished structure shall be removed or cut off at least 1 ft below either the bottom

of footing or the finished ground elevation if not located within the footing area.

550

701.06Blank

701.07Piling Length

The lengths of piles shown on the plans and in the Schedule of Pay Items are

estimated lengths and are for bidding purposes only. The Contractor shall provide the

actual length of piles necessary to obtain the nominal driving resistance and

penetration depth required as determined from results obtained from driving

representative test piles or other pertinent data. There will be expected variations in

final tip elevations due to differences in nominal pile driving resistance. The final tip

elevation of each pile will be determined during the driving operation. If minimum tip560

elevations are specified, the Contractor shall drive piles to a penetration depth that

satisfies this requirement in addition to the nominal driving resistance. If no

penetration depth or minimum tip elevation is specified, the pile shall be driven a

minimum of 10 ft below the bottom of the footing elevation. The Contractor shall also

furnish satisfactory evidence as to the identification, such as heat numbers for steel

piles, of all portions of a built-up pile.

701.08Nominal Driving Resistance of Production Piles

Production piles shall be driven the depth necessary to obtain the required nominal

driving resistance as determined by 701.05. If a minimum pile tip elevation is shown570

on the plans, in addition to obtaining the required nominal driving resistance,

production piles shall also be driven to the minimum pile tip elevation or to practical

refusal.

When the nominal driving resistance is determined in accordance with 701.05(a),

for acceptance, the Engineer will record, at a minimum, the number of hammer blows

701.08

610

per inch or per foot of pile movement for the last 24 in. of driving. When the nominal

driving resistance is determined in accordance with 701.05(b), for acceptance, the

Engineer will record the blow count per inch or foot of pile movement and the

associated hammer stroke for the last two consecutive feet of driving, and the final pile580

tip elevation as per the pile driving criteria established through the dynamic pile load

test.

Practical refusal will be defined as 20 blows per inch of penetration with the

hammer operated at its maximum fuel or energy setting, or at a reduced fuel or energy

setting recommended by the Engineer based on pile installation stress control and less

than 1/4 in. rebound per blow. The Contractor shall stop driving as soon as the

Engineer determines that the pile has reached practical refusal.

The nominal driving resistance of jetted piles shall be based on impact driving590

penetration resistance after the jet pipes have been removed. Jetted piles not attaining

the nominal driving resistance at the ordered length shall be spliced and driven with

an impact hammer until the nominal driving resistance is achieved in accordance with

the driving criteria in 701.05.

The required nominal driving resistance of piles driven with followers will only

be considered acceptable if the piles with followers attain the same tip elevation as the

full length piles driven without followers, installed in accordance with 701.04(c)5.

The required nominal driving resistance of piles driven with vibratory hammers600

shall be based on the driving resistance recorded during impact driving after the

vibratory equipment has been removed from the first pile in each group of 10 piles.

Vibrated piles not attaining the nominal driving resistance at the ordered length shall

be spliced and driven with an impact hammer until the nominal driving resistance is

achieved in accordance with the driving criteria in 701.05. Once the nominal driving

resistance is attained, the remaining nine piles in the group shall be installed to similar

penetration depths with similar vibratory hammer power consumption and rate of

penetration as the first pile.

701.09Preparation and Driving610

For steel and timber piling, the pile heads shall be plane and perpendicular to the

longitudinal axis of the pile before the helmet is attached. The pile heads shall be

protected with a hammer cushion.

Precast concrete pile heads shall be flat, smooth, and perpendicular to the

longitudinal axis of the pile. Prestressing strands shall be cut off below the surface of

the end of the pile. The pile head shall be chamfered on all sides. The heads of all

concrete piles shall be protected with a pile cushion.

Approval of a pile hammer relative to driving stress damage will not relieve the620

Contractor of responsibility for piles damaged due to misalignment of the leads, failure

of hammer cushion or cushion material, failure of splices, malfunctioning of the pile

701.09

611

hammer, or improper construction methods. Piles damaged for such reasons will be

rejected and shall be replaced if the Engineer determines that the damage impairs the

strength of the pile.

Pilot holes are prebored, predrilled, or cored. After a pile is driven thru a pilot

hole, all voids around the pile shall be filled with B borrow. Water shall be added to

the hole to saturate the final placement of B borrow.630

If the Engineer determines that preboring or predrilling has disturbed the nominal

driving resistance of previously installed piles, those piles that have been disturbed

shall be restored by means of redriving or other approved remedial measures.

Redriving or other remedial measures shall be instituted after the preboring or

predrilling operations in the area have been completed.

When shown on the plans, the Contractor shall prebore holes at the locations

shown and to the depth specified. Prebored holes shall be 2 in. smaller than the640

diameter or diagonal of the pile cross-section that is sufficient to allow penetration of

the pile to the specified depth. If subsurface obstructions, such as boulders or rock

layers, are encountered, the hole diameter may be increased to the least dimension

which is adequate for pile installation.

Augering, wet-rotary drilling, spudding, or other methods of preboring shall be

used only when specified or approved in writing by the Engineer. The procedures shall

be carried out so as not to impair the nominal driving resistance of the piles already in

place or the safety of existing adjacent structures.

650

Except for end bearing piles, preboring shall be stopped at least 5 ft above the pile

tip elevation shown on the plans. The pile shall be driven with an impact hammer to

the specified penetration resistance. Where piles are to be end-bearing on rock or

hardpan, preboring may be carried to the surface of the rock or hardpan. The piles shall

then be driven with an impact hammer to ensure proper seating.

The hole shall have a minimum diameter of not less than the greatest dimension

of the pile cross-section plus 4 in. The holes shall be drilled to the elevations shown

on the plans.660

Before driving piles for end bents, holes to receive piling shall be predrilled or

spudded through new embankment to the original ground elevation if the new

embankment is 10 ft or more in height. If the new embankment is less than 10 ft in

height, predrilling is not required. If new embankment in the area of the end bents is

to be constructed of sand, gravel, or other permeable material in which a predrilled

hole would not remain open, the piling shall be driven before the embankment is

constructed.

701.09

612

Pilot holes for end bent piles for structures with integral end bents shall be670

predrilled to the depth specified in the plans, regardless of the height of new

embankment.

If pile sleeves are shown on the plans, the drilled holes shall be sleeved to maintain

the opening during the driving of the piles.

If bentonite grout is shown on the plans, it shall be used to fill the annular space

around the pile. The grout shall be placed at the depths shown on the plans or as

directed. The entire annular space shall be filled from the bottom upwards to the top

of the pile in one pumping operation using a tremie pipe.680

Tremie pipe construction shall include side discharge ports. The tremie pipe can

be terminated by means of a tee connection. Tremie pipe may be PVC, however, joints

shall not be glued or cemented.

When specified, holes shall be cored into rock to accommodate pile placement.

The approach grade shall be completed before coring is begun. Holes of the diameter

shown on the plans shall then be predrilled through the embankment into solid rock to

the elevations shown on the plans or as otherwise directed. The piles shall be driven690

to practical refusal at the bottom of the cored holes. The holes in cored rock shall then

be filled with concrete.

A maximum deviation of 1 1/2 in. in any direction from the plan position will be

allowed in pile trestle bents and exposed pile bents. A maximum deviation of 6 in. in

any direction will be allowed for a foundation pile in footings for piers or abutments.

The tendency of concrete or steel piles to twist or rotate shall be prevented and

corrected. Piles to be swaybraced shall be aligned as necessary so that the swaybracing

may be properly welded to the piles by a welder qualified in accordance with 711.32.700

No pile shall be closer than 4 in. from an edge of the pile cap. Pulling or pushing

laterally on installed piles to correct misalignment or splicing a properly aligned

section on a misaligned section will not be allowed. The pile head at cutoff elevation

shall be within 2 in. of plan elevation for bent caps supported by piles.

Piles driven at integral end bents shall be installed so that the axial alignment of

the top 10 ft of the pile is within 2% of the specified alignment.

Battered piles shall be installed so that the alignment of the top 10 ft of the pile

does not vary by more than 3% from the batter rate shown on the plans.710

If the location or alignment tolerances are exceeded, the extent of overloading

shall be investigated. If the Engineer determines that corrective measures are

701.09

613

necessary, such corrective measures shall be designed and constructed by the

Contractor. Proposed corrective measures will be subject to approval by the Engineer.

The Contractor shall take an elevation reading on each pile in a foundation

immediately after each pile in that foundation has been driven and again after all piles

in that foundation have been driven. Elevation readings for checking pile heave shall720

continue until the Engineer determines that such checking is no longer required. All

piles which have heaved more than 1/4 in. shall be redriven to the required resistance

or penetration. If pile heave is detected for pipe piles, the piles shall be redriven to

original position prior to filling with concrete. A hammer-pile cushion system shall be

submitted and approved prior to redriving pipe piles which have been filled with

concrete.

The order of placing individual piles within a pile group shall begin from the

center of the group and proceed outward in both directions unless an alternate730

installation sequence is approved in writing. For a bent with a single row of piles, pile

driving shall begin at one end of the bent and proceed toward the opposite end.

The Engineer shall be given a minimum of 24 h notice before driving piling. No

pile shall be driven except in the presence of the Engineer.

Prior to placing concrete in driven pipe piles, the Contractor shall supply suitable

lighting for the inspection of each pipe pile by the Engineer throughout its entire

length.740

After all water and other foreign substances have been removed from the pipe

piles and the final approval given, reinforcing bars, if specified, shall be placed, and

the pipe piles shall be filled with class A concrete in the presence of the Engineer.

Concrete shall be deposited into pipe piles in a stream with a cross-sectional area that

is no more than approximately 50% of the area of the pipe pile to prevent air pockets

from forming. At a minimum, concrete shall be vibrated in the upper 25 ft of the pipe

piles. Concrete shall not be placed in pipe piles until all pile driving has progressed

beyond a radius of 15 ft from the pile to be filled. All pile driving within the above750

limits shall be discontinued until the concrete in the last pile cast has cured for a

minimum of 48 h.

701.10Unsatisfactory Piles

The method used in driving piles shall not subject the piles to excessive or undue

abuse which produces deformation of the steel, injurious splitting, splintering, and

brooming of the wood, or crushing and spalling of the concrete. All piles damaged

during driving due to internal defects, improper driving, being driven out of its proper

location, or being driven below the designated cutoff elevation shall be corrected as

directed.760

701.10

614

Piles which have been bent, or otherwise damaged, during installation shall be

considered unsatisfactory unless the nominal driving resistance is proven by load tests

performed by the Contractor. If such tests indicate inadequate pile resistance,

corrective measures such as the use of the bent piles at reduced pile resistance,

installation of additional piles, strengthening of the bent piles, or replacement of the

bent piles shall be done as approved by the Engineer.

A concrete pile will be considered defective if a visible crack appears around the

entire periphery of the pile or if a defect is observed, as determined by the Engineer.770

701.11Splicing Piles

Full length piles shall be placed in the leads if practical. However, if splicing is

necessary, the following methods shall be used.

Splicing of steel piles shall be made as shown on the plans. The top of the pile to

be extended shall be restored to its original cross-section shape. The mating end of the

other pile shall be beveled as shown on the plans. A wire brush or grinder shall be used

to remove any scale, dirt, slag, or other foreign material that is detrimental to780

fabricating a sound weld from all surfaces to be welded. For H piles, a mechanical

splice shall not be used within 20 ft of the ground surface unless it is proven that the

splice can transfer the full pile strength in compression, tension, and bending. Splices

for pipe piles shall be watertight. All work shall be done with approved methods and

materials and by welders qualified in accordance with 711.32. If the temperature of

the piles is below 50°F, both piles to be spliced shall be preheated to a minimum

temperature of 70°F in the vicinity of the splice immediately prior to welding. The

temperature of the piles shall be maintained at a minimum of 50°F until the welding

is complete. There shall not be more than two splices exposed to view in each length

of piling after driving is completed. A mechanical splice shall not be used in integral790

end bents.

Timber piles shall not be spliced.

Full length concrete piles shall be used where practical. If splicing is necessary,

concrete splice details shall conform to the contract documents. Mechanical splices

including drive-fit splices may also be used if the splice can transfer the full pile

strength in compression, tension and bending.800

701.12Blank

701.13Cut-Off Lengths

The tops of all steel pile shall be cut off at the elevation shown on the plans. All

unused cut-off lengths shall become the property of the Contractor and shall be

removed from the project site.

701.11

615

The length of timber pile above the elevation of cut-off shall be sufficient to

enable the complete removal of all material injured by driving. Immediately after810

making final cut-off on treated timber foundation piles, the cut area shall be treated

with copper naphthenate in accordance with AWPA Standard M4.

Timber piling supporting timber structures where the piles are cut off, but not

concrete capped, shall be treated with copper naphthenate in accordance with AWPA

Standard M4. A layer of saturated building felt or fiberglass cloth which overlaps the

side of the pile at least 2 in. shall be securely fastened and completely covered with 20

gauge thick galvanized metal or aluminum sheeting. All cuts, injuries, and holes,

which occur from removal of nails or spikes that penetrate the treating zone as well as

bolt holes for connections, shall be treated by applying coal-tar roof cement in820

accordance with ASTM D5643.

701.14Method of Measurement

The driven length of treated timber piles, untreated timber piles, steel pipe piles,

steel H piles, and concrete piles will be measured by the linear foot to the nearest 0.1

ft. This includes piles used as indicator test piles, dynamic test piles, or static load test

piles. Measurement will be made only for the actual number of linear feet of piling

complete in place. For concrete piles, this length will not include extensions or the

portion of the pile cutoff to make the extension.

830

Dynamic pile load test, static pile load test, indicator test pile restrike, dynamic

test pile restrike, pile shoes, and conical pile tips will be measured per each.

The limits of the epoxy coated steel pipe portion of the pile will be measured by

the linear foot to the nearest 0.1 ft as shown on the plans.

Prebored holes and cored holes in rock will be measured by the linear foot

complete in place of the diameter specified.

Class A concrete, reinforcing bars, epoxy coating, reaction piles if not used as840

production piles, splices, end plates, predrilling, cleaning of drilled holes, drilling

fluids, sealing materials, casing, jetting, followers, spudding, or other methods used to

facilitating pile driving will not be measured for payment.

Reinforced concrete encasement for steel H piles will be measured by the linear

foot as shown on the plans.

701.15Basis of Payment

All treated timber piles, untreated timber piles, steel pipe piles, steel H piles, and

concrete piles driven will be paid for by the linear foot. Payment will be made only for850

the actual number of linear feet of piling complete in place. Extensions for concrete

piles will be paid for in accordance with 109.05.

701.15

616

Driven piles used as indicator test piles or dynamic test piles that are left in place

and subsequently used as production piles will be paid for by the linear foot as either

production indicator test piles or production dynamic test piles. Reaction piles used in

a static pile load test that are left in place and subsequently used as a production pile

will be paid for by the linear foot as the type of production pile they represent. Driven

piles used as indicator test piles, dynamic test piles, or static load test piles that are not

used as production piles will be paid for by the linear foot as non-production dynamic,860

indicator, or static test piles respectively.

If the quantity of driven piling is less than the plan quantity or the quantity as

ordered by the Engineer, the Department will pay 50% of the cost to re-stock unused

piling if the Contractor elects to re-stock piling and provides a paid invoice showing

the re-stocking fee. Payment will be made for piling, restock.

The epoxy coated portion of the piles may be furnished and driven at lengths

greater than those shown on the plans. These additional lengths of epoxy coated piles

left in place and accepted will be paid for as the uncoated portion below the plan limits870

of required epoxy coating.

Prebored holes and cored holes in rock will be paid for at the contract price in

linear feet.

Payment will be made under:

Pay Item Pay Unit Symbol

Conical Pile Tip, ________ ....................................................... EACH880

pile size

Cored Hole in Rock, ______ in. ................................................ LFT

diameter

Dynamic Pile Load Test ............................................................ EACH

Pile Shoe, ________ .................................................................. EACH

pile size

Pile, Concrete _____ x _____.................................................... LFT

size

Pile, Prestressed Concrete _____ x _____ ................................. LFT

size890

Pile, Steel H, Epoxy Coated, HP _____ x _____ ...................... LFT

size

Pile, Steel H, HP _____ x _____ ............................................... LFT

size

Pile, Steel Pipe, ____________, ________ ............................... LFT

pipe wall thickness diameter

Pile, Steel Pipe, Epoxy Coated, ____________, ________ ...... LFT

pipe wall thickness diameter

Pile, Timber ............................................................................... LFT

701.15

617

Pile, Timber, Treated ................................................................. LFT900

Piling, Restock........................................................................... LS

Prebored Hole, _______ in. ....................................................... LFT

diameter

Reinforced Concrete Encasement for H Piles ........................... LFT

Static Pile Load Test, ________ ................................................ EACH

pile size

Test Pile, Dynamic, ________, Non-Production ....................... LFT

pile size

Test Pile, Dynamic, Production ................................................. LFT

Test Pile, Dynamic, Restrike ..................................................... EACH910

Test Pile, Indicator, ________, Non-Production ....................... LFT

pile size

Test Pile, Indicator, Production ................................................. LFT

Test Pile, Indicator, Restrike ..................................................... EACH

Test Pile, Static Load, ________, Non-Production ................... LFT

pile size

All costs associated with the dynamic pile load test except the cost of the test pile

and test pile restrike shall be included in the cost of the dynamic pile load test.

920

All costs associated with the static pile load test except the cost of the test pile

shall be included in the cost of the static pile load test. The cost of reaction piles used

in the static load test and not incorporated into the work as production piles shall be

included in the cost of the static load test.

The cost of furnishing and placing concrete, B borrow, or bentonite grout

necessary to fill pilot holes, and all necessary incidentals shall be included in the cost

of the pay items of this section.

The cost of the following shall be included in the cost of the piling.930

701.15

618

specifications,

No additional payment will be made if the Contractor elects to furnish and drive

thicker walled pipe piles than specified.

An increase in the size of a pile cap to satisfy edge distance clearance

requirements, when approved, shall be at no additional cost to the Department.

960

If the method for driving the piles is specified as 701.05(b) and the contract is a

local public agency contract, the Contractor shall include the cost of acquiring the PDA

consultant in the cost of the Dynamic Pile Load Test.

The cost of mobilization and demobilization for pile driving operations shall be

included in the cost of mobilization and demobilization in accordance with 110.04.

The cost to control sediment in water from jetting operations shall be included in

the cost of the piling.

970

The cost of forms, falsework, class A concrete, reinforcing bars, and necessary

incidentals shall be included in the cost of reinforced concrete encasement for H piles.