- 465 - SECTION 703 -- PILES AND PILE DRIVING
703.01 Description
1.This work shall consist of furn ishing, driving, cutting, and extending all bearing and sheet piles. They shall be driven or placed in accordance with the requirements of these Specific ations at the locations, elevation, penetration, and bearing shown in the contract.
2.Only one type of concrete piling may be used in any one structure. Before construction begins, the Contra ctor shall advise the Engineer in writing which type is to be furnished at each structure.
703.02 Material Requirements
1.All materials shall conform to the requirements in Table 703.01. Table 703.01 Material Requirements Applicable Materials Section Portland Cement Concrete ....................................... 1002 Reinforcing Steel ....................................................... 1020, 1023, 1024 Epoxy Coated Reinfo rcing Steel ............................... 1021 Structural Steel (B earing Pile s) ................................. 1045 Steel Sheet Piles and Sheet Pile Corners ................. 1056 Sheet Zinc ................................................................. 1053 Sheet Alum inum........................................................ 1054 Precast P iles ............................................................. 705
2.Steel Piling:
a.Pipe pile shall meet the requirements in ASTM A 252, Grade 2.
b.Sheet pile and sheet pile corners shall meet the requirements in ASTM A 328/A 328M.
c."H" pile shall meet the requirements in ASTM A 6/A 6M.
3.Pre-Cast Piling:
a.Pre-cast concrete piling shall meet the requirements in Section 705.
4.Cast-In-Place Concrete Piles:
a.Piles shall be constructed in accordance with the details shown in the contract.
b.Materials: (1) The class of concrete used in cast-in-place concrete piles shall be as shown in the contract. Maximum slump for concrete used in cast- in-place piling shall be 6 inches (150 mm).
2.When the contract allows for the use of more than one class of concrete, the Contractor shall ad vise the Engineer, in writing, of the class of concrete to be used 14 da ys before the date of beginning the concrete work.
3.No change shall be made in the concrete class without written permission of the Engineer.
4.Reinforcement shall be furnished, handled, stored, and placed in accordance with the r equirements of Section 707.
703.02 Piles and Pile Driving
- 466 - (5) Pile shells for cast-in-place concrete bearing piles shall be metal shells of the type, size, and gauge indicated in the contract.
c.Concrete Placement:
1.After driving and before the placing of any concrete, the Engineer shall examine each shell throughout its entire length. If any shell is broken or otherwise defective, the C ontractor shall remove and replace the shell or abandon the defective shell and drive a new shell. The Engineer will choose the location of the new shell.
2.All shells for cast-in-place concrete piles supporting bents, piers, or abutments shall be fully driven before any pile in that unit is filled with concrete.
3.Water inside the shells shall be removed before the concrete is placed.
4.Concrete shall be placed in accordance with the requirements of Section 705.
5.Concrete shall be placed continuously and shall be vibrated only in the areas wh ich contain reinforcing steel.
6.The shells shall be overfilled, the surplus concrete struck- off, and the top surface finished to a uniform, even texture.
5.Order requirements:
a.The Contractor shall furn ish piles for each structure in accordance with the itemized list in the contract showing the number and lengths of all piles required.
b.The Contractor may, without additional compensation, increase the lengths given in order to suit the Contractor's method of operation.
c.Heat numbers shall be clearly visible on each pile.
d.Prefabricated pile points sh all conform to the requirements of ASTM A27 Grade 70-36. A list of approved manufacturers of prefabricated pile points are on the Department ’s Approved Products List.
6.Downgraded or salvaged piles are not to be used. 7. Storing and Handling Piling: a. Piles shall be stored on suitable skids or platforms. Piles shall be kept free from accumulations of di rt, oil, or other foreign matter.
b.If the Contractor uses bearing piles or sheet piles for falsework, trackways, or any other purpose than sh own in the contract, such use will be at his/her own risk and any damaged piles shall be rejected for use as material in the permanent structure.
703.03 Construction Methods
1.Preparation for Driving Piles: a. The Hammer Data sheet shall be required for the wave equation analysis. (The wave equation is a computer program that analyzes the hammer-pile system.) The Contra ctor shall submit a completed data sheet for each hammer to be used, to the Engineer, at least 21 days before its use. The Engineer will notify the Cont ractor, within 10 days of the receipt Piles and Pile Driving 703.03 - 467 - of the hammer data, as to whether or not the hammer is acceptable. A typical Hammer Data sheet is shown in Figure 703.01.
b.The wave equation analysis may indicate that the hammer system may not be able to drive the pile to minimum penetration without damage to the pile. In this case, the Contractor shall modify the hammer system and submit a new Hammer Data sheet to the Engineer. The new data will be analyzed to determine if t he modifications to the hammer system are adequate to allow the pile to be driven to minimum penetration without damage.
c.Hammers shall not be replaced or changed unless authorized by the Engineer. The Contractor shall submit a new Hammer Data sheet if hammers are changed.
d.The Contractor shall comple te foundation pile pit excavations before driving the piles. After the piles are driven, all loose and displaced material shall be removed, leaving a smooth solid bed to serve as a concrete form.
e.The Engineer will use a saximeter to measure the height of the fall of the ram on a single acting diesel hammer. If a saximeter is not available, the Contractor, when using a single-acting diesel hammer, shall be required to have a measuring rod rigidly fixed to the hammer which will indicate the ram stroke in feet (meters). The measuring rod shall be divided into 3 inch (75 mm) increments and shall be readable from the ground.
1.The Contractor may provide a saximeter for the Department's use.
f.The Contractor, when using a double-acting diesel hammer, shall furnish an appropriate gauge and chart to measure the bounce chamber pressure and resulting hammer output. The gauge shall be readable from the ground.
g.Cushioning Material: (1) Wood or steel cable shall not be allowed for use as a hammer cushion.
2.Wood can be used as a pile cushion. (3) If fresh cushioning material has been inserted over the head of the pile, the penetration measurements for the purpose of determining the final bearing values shall not be made until at least 10 blows are struck.
j.Piles shall not be driven with out the use of a closely fitting cap or driving head. This cap or driving head shall be of such design as to distribute the blow of the hammer thr oughout the cross section of the pile.
703.03 Piles and Pile Driving
- 468 - HAMMER DATA Hammer Manufacturer: ........... Model: ...................... Type: ........................ Serial No.: ................ Ram Wt.: .................. Hammer Cushion Material: ................... Thickness: ................ Area: ......................... Pile Cap Weight: ..................... Cap Inse rt: ................ Pile Cushion (For Concrete Piles Only) Material: ................... Thickness: ................ Area: ......................... NOTE: Proposed pile cushion thickness and/or area may be modified by the engineer after wave equation analysis. Figure 703.01 Ram Anvil Piles and Pile Driving 703.03 - 469 - k. Full length piles shall be used where practical. Optional field splices will be allowed for steel "H" pili ng, pipe piling, and cast-in-place pile shells as follows:
1.One optional field splice will be allowed on piling more than 40 feet (12.2 m) long and less than 80 feet (24.4 m) long. Two optional field splices will be allowed for piling over 80 feet (24.4 m) long and less than 120 feet (36.6 m) long. Three optional fi eld splices will be allowed for piling over 120 feet (36.6 m) long. The method of splicing shall be as shown in the contract.
2.Prefabricated pile splices of an approved type and source will be allowed for use on steel "H" pili ng, pipe piling, and cast-in-place pile shells. The splices shall be attached and welded in place in accordance with the manufacturer's recommendations.
3.Preidentified splices shall be made before driving the pile, and the shortest side of the splice will be placed in the ground first.
l.Except where piles are dr iven through water, the use of a follower pile will not be allowed.
m.Welding:
1.All welding to be done on steel piles shall be in accordance with the contract and the a pplicable requirements of Section 708 in the Standard Specifications. Welder qu alification certific ation is required and must be submitted to the Bridge F abrication Manager for approval prior to any welding. All field welding on steel piles shall be done in the SMAW process using electrode E7018.
2.Welders shall be experienced in pile welding. 2. Pile Driving Methods:
a.Concrete and Steel Bearing Pile:
1.Concrete and steel bearing piling shall be driven with a steam, air, or diesel hammer developin g a manufacturer's rated energy such that when all known values are substituted in the applicable dynamic formula, "P" (bearing capacity in kips) shall be not less than 125% of the required design bearing when an "S" (penetration rate) of 0.05 inch (1 mm) per blow is assumed. In no case shall a power hammer have a ram weight of less than 2,000 pounds (900 kg) nor develop a manufacturer's rated energy of less than 8 Ft.-Tons (20 KJ).
2.Water or air jets may be used to assist in driving the piling. (3) Concrete and steel bearing piles may be driven with a gravity hammer for the first half of the pile’s penetration below ground provided that the bearing of the driven pile does not exceed one-third of the design bearing.
4.Steel pipe, "H" pile, and cast-in-place piling may be driven with a vibratory hammer for the first half of the driven length.
b.Steel Sheet Pile: (1) Steel sheet piling shall be driven with a steam hammer, air hammer, diesel hammer, vibrator y hammer, gravity hammer, or a combination of water or air jets and hammer.
703.03 Piles and Pile Driving
- 470 - (2) Steel sheet piles shall not be driven without the use of a closely fitting cap or driving head. This cap or driving head shall be of such design as to distribute the blow of the hammer throughout the cross section of the pile.
c.When gravity hammers are allowed the following requirements will apply:
1.The minimum weight of gravity hammers which may be used for driving shells for cast-in-place concrete , pipe piles, and steel bearing piles shall be as shown in Table 703.02. Table 703.02 Minimum Gravity Hammer Weight Design Bearing Capacity of Pile in Kips (kN) Gravity Hamme r Weight in Pounds (kg) 16 – 24 (70-105) .............................. 2, 000 (900) More than 24 – 30 (105- 135) ............................. 2, 500 (1100) More than 30 – 44 (135- 195) ............................. 2, 800 (1250) More than 44 – 56 (195- 250) ............................. 3, 000 (1350) More than 56 – 74 (250- 330) ............................. 3, 500 (1600) More than 74 – 100 (330 -445) ........................... 4, 000 (1800)
2.The weight of the gravity hammer for driving precast concrete bearing piles shall not be less than 30% of the weight of the pile and never less than 2,000 pounds (900 kg).
3.The fall of gravity hammers shall be operated so as to avoid damage to the piles.
d.Leads:
1.No pile shall be driven without the use of leads. Pile driver leads shall be designed to afford free movement of the hammer and shall support the pile and hammer in proper pos ition during driving. The stroke of the hammer shall be accurately in line wi th the axis of the pile. Leads, pile, and hammer shall be held in proper vertical or battered alignment to place the piles within the tolerances allowed.
2.Swinging leads may be used with steam, air, or diesel hammers if the results obtained meet all requirements of these Specifications.
3.Pile driver leads used with gravity hammers shall be guyed, braced, or fixed.
e.When water or air jets are used, the number of jets and the volume and pressure at the jet nozzles shall be sufficient to freely erode the material adjacent to the pile. Before the desired penetration is reached, the jets shall be withdrawn and the piles shall be driven with the hammer to secure the final penetration.
f.Augured Holes: (1) The Contractor has the opt ion of starting piling in augured holes. Piles and Pile Driving 703.03 - 471 - (2) Augured hole length shall not exceed 30% of the below-ground length of the pile.
3.Augured hole diameters shall not be more than 2 inches (50 mm) larger than the pile.
3.Tolerance for Bearing and Sheet Piles: a. Piles shall be driven to the depth and bearing shown in the contract or to "practical refu sal", whichever occurs first.
b.Piles shall be driven plumb or to the batter indicated in the contract. Piles that do not meet the following criteria shall be rejected.
1.No variation greater than 1/4 inch per foot (6mm per 300 mm) (2%) from vertical or the batter line indicated shall be allowed.
2.In no case shall the top of a bearing pile be out of line more than 3 inches (75 mm).
3.The tops of sheet piles s hall not be out of position by more than 2 inches (50 mm).
4.Adjacent sheets shall not be out of line with each other by more than 0.4 inch (10 mm).
c.(1) Broken, split, or misplaced piles shall be withdrawn and properly replaced; or, with the permission of the Engineer, a second pile may be driven in place thereof.
2.Piles driven below cutoff grade shall be withdrawn and replaced with new piles.
d.Should the driving of any pile cause previously driven piles to rise, the Contractor shall drive them back to their described elevations.
4.Determination of Bearing Capacity: a. The Engineer will compute the bearing capacity of every pile. b. The Engineer will comput e the bearing capacity of at least 1 pile in each substructure (i.e., bent, abutment, or pier) at 5 foot (1.5 m) penetration intervals.
c.The Contractor sha ll drive piles continuously.
1.When the driving has been interrupted for more than 2 hours, the pile shall be driven at least 12 inches (300 mm) before the determination of the bearing value is made.
2.Should the 2 hour interruption occur when the piling is within 12 inches (300 mm) of cutoff, then the bearing capacity shall be taken in the last 10 blows just bef ore reaching cutoff elevation.
3.An explanatory note should be included on the pile driving report when the pile was driven less than 12 inches (300 mm) or when less than 10 blows were averaged for the bearing capacity due to an unforeseen interruption.
4.Driving the pile at least 12 inches (300 mm) is to determine the uniformity of bearing capacity between piling and is not intended to determine a setup factor.
703.03 Piles and Pile Driving
- 472 - (5) The head of the pile shall not have any broomed or crushed fibers.
6.The pile penetration shall be quick and at uniform rate. (7) Deviations or problems shall be noted by the Engineer on the driving report.
d.The bearing capacity of pile s shall be computed from one of the following formulas: Dynamic Formulas (English) 3.5 WH W P = S+0.35 x W+M For gravity hammers. 3.5 E W P = S+0.1 x W+M For steam hammers. 3.5 E W For driving steel, steel shell and P = S+0.1 x W+M pipe piles with diesel hammers. 1.6 E P = S+0.1 For driving mandrel driven pile shells. 7.0 E W For driving concrete bearing pile P = S+0.1 x W+M with diesel hammers. Where: P = the bearing capacity, in tons W = the weight of the ram, in tons M = the weight of the pile and driving cap, in tons S = the average penetration, in inches of the last 10 blows. H = the height of fall of the ram, in feet (less twice the height of bounce for gravity and steam hammers) E = the energy per blow in foot-tons For double-acting steam hammers, E = W x H. For diesel hammers, the value of E in foot-tons shall be in accordance with Manufactures recommendations. Unless permitted by the Department’s Geotechnical Section, all piles driven with hammers other than single-acting diesel hammers shall be tested with the Pile Driving Analyzer to verify capacity. Piles and Pile Driving 703.03 - 473 - Dynamic Formulas (Metric) 2.9 WH W P = S+9.0 x W+M For gravity hammers. 290 E W P = S+2.5 x W+M For steam hammers. 250 E W For driving steel, steel shell, and P = S+2.5 x W+M pipe piles with diesel hammers 130 E P = S+2.5 For driving mandrel driven pile shells. 580 E W For driving concrete bearing pile P = S+2.5 x W+M with diesel hammers. Where: P = the bearing capacity, in kN. W = the mass of the ram, in kN. M = the mass of the pile and driving cap kN. S = the average penetration, in m illimeters of the last 10 blows. H = the height of fall of the ram, meters (less twice the height of bounce for gravity and steam hammers) E = the energy per blow in meter-kilogram. For double-acting steam hammers, E = W x H. For diesel hammers, the value of E in kilojoules shall be in accordance with Manufactures recommendations. Unless permitted by the Department’s Geotechnical Section, all piles driven with hammers other than single-acting diesel hammers shall be tested with the Pile Driving Analyzer to verify capacity.
1.For bridges with design live load “HL-93”: Dynamic Formulas (English) Diesel Hammers: P = 4.0 E S+0.5 For all piles driven from the top with a single-acting diesel hammers (English) Where: P = the bearing capacity, in kips S = the average penetration per blow, in inches of the last 10 blows E = the energy per blow in foot-kips (English) or meter-kilogram (Metric). For single-acti ng diesel hammers, E = W x H W = the weight of the ram, in kips H = the height of fall of the ram, in feet (less twice the height of bounce for gravity and steam hammers) Unless permitted by the Department’s Geotechnical Section, all piles driven with hammers other than single-acting diesel hammers shall be tested with the Pile Driving Analyzer to verify capacity.
e.When using double-acting diesel hammers, the hammer energy shall be read from the bo unce chamber pressure gauge and computed from the bearing chart. The hammer energy used to compute pile bearing shall not exceed the manufacturer's energy rating.
f.If piling driven to the described depth fails to obtain the required bearing capacity, the Engineer will temporarily suspend driving.
703.03 Piles and Pile Driving
- 474 - (1) The Engineer will reevaluate pile requirements and notify the Contractor of proposed revisions wi thin 2 NDOT work days from the time driving was suspended.
g.Soil-Setup Factor:
1.In certain silt, clay, or very fine sand soils, the initial bearing computed by the formulas in this Section may not accurately represent the long-term bearing capacit y of the pile. In such cases, the Engineer will request data to ca lculate soil-setup factors.
2.Whenever a setup factor is to be established for a group (i.e., abutment and wings, grade beam, ben t, or pier), 2 representative piles shall be driven to within 2 feet (600 mm) of the cutoff elevation shown in the contract and the bearing shall be co mputed on the basis of the average penetration of the last 10 blows, this will be considered the bearing achieved at the End of Original Drive (EOD). T he piles will then be allowed to rest undisturbed for 36 hours. In the case of twin bridges, each shall be considered a separate bridge for the determination of soil setup factors.
3.Soil-Setup Determination: (i) After 36 hours have elapsed, the hammer shall be warmed up on the first Pile. This pile shall be driven to cutoff elevation. The bearing of the first Pile is not relia ble if the hammer is not warmed up. (ii) The hammer shall then be placed on the second Pile and the bearing computed on the basis of the average penetration of the first 10 blows. This pile shall be driven to cutoff and the bearing also computed on the basis of the averag e penetration of the last 10 blows required to bring the pile to cutoff elevation. (iii) The bearing capacity computed on the basis of the first 10 blows shall be reported to t he Engineer, and the Engineer will determine a setup factor. This factor may then be used to increase the computed bearing of the ot her piles in the group. (iv) The soil-setup factor shall be determined by a ratio of two computed bearing loads for the same pile. The computed bearing load determined for the first 10 blows after a piling that has rested undisturbed for a minimum of 36 hours is bearing achi eved at the Beginning of Restrike (BOR) as determined in paragraph (3) (ii). The soil-setup factor is the ratio of the BOR divided by the EOD as determined in paragraph (2).
4.The Engineer may monitor the pile driving during the set up determination with the Pile Driving Analyzer. The Engineer shall prepare the pile for dynamic testing, and the Contractor shall attach and detach the gauges.
5.Test Piles: a. Test Piles shall be driven at the locations shown in the contract. The Contractor shall give t he Engineer a 7 day notice as to when he/she proposes to drive each test pile. The Engineer will monitor each test pile with a Pile Driving Analyzer.
b.When the pile order lengths ar e indicated as "tentative" in the contract, the final order lengths will be based on results obtained from the test pile driving. Piles and Pile Driving 703.03 - 475 - c. The Department will provi de the Pile Driving Analyzer and gauges.
d.The test piles shall be restruck a minimum of 36 hours after initial driving to determine a soil-setup factor. Restriking shall be subsidiary to the test pile. The restrike will be monitored with the Pile Driving Analyzer.
e.The Contractor shall bolt two accelerometers and two strain transducers to the pile before driving is started. The holes or anchors for the accelerometers and strain transducers will be predrilled by Department personnel while the pile is still on the ground.
f.The Contractor may be required to stop the hammer for wave speed determination after the first few blows.
g.The Contractor shall drive the pile until the transducers are near the ground surface or as directed by the Engineer, at which time the Contractor shall stop the hammer and re move the accelerometers and strain transducers.
h.The Contractor shall continue driving the pile to cutoff elevation or as directed by the Engineer.
i.The time delay occurring when driving a pile monitored by the Pile Driving Analyzer will normally range from 30 to 60 minutes.
j.The test pile shall be incorporated into the foundation and become a load bearing pile.
k.The Engineer will provide final order lengths to the Contractor within 3 NDOT work days after the test pile is driven.
l.Test piles and the service piles shall be driven with the same hammer for each structure.
6.Practical Refusal: a. "Practical refusal" occurs when the actual bearing capacity is 2.0 times the Design Pile Bearing.
b.If a pile is at "practical refusal", driving shall be suspended. When "practical refusal" is reached bef ore the pile has been driven to the specified minimum depth, the Engineer may require the Contractor to supplement the equipment with an adequate jetting system. By this means, the Contractor shall loosen the pile an d continue to drive to the specified depth.
c.The Engineer may require pr edrilling through the material that is causing premature refusal for subsequent piling.
7.Elevation of Piles and Cutoff: a. Piles shall be driven to t he specified depth and cut off at the elevation shown in the contract. The ent ire order length may be driven if the pile top is not damaged.
b.Prestressed concrete piling shall be cut off to the shape specified.
i.A saw cut, to the depth of the prestressing strands, shall be made at cutoff elevation ar ound the perimeter of the pile.
703.03 Piles and Pile Driving
- 476 - (ii) After the saw cut is completed, a chipping tool shall be used to expose the prestressing strands for burning. (iii) The Contractor shall remove the excess portion of the concrete pile after cutting the prestressing strands. (iv) The Contractor shall remove and replace piles that have been broken or damaged.
8.Extensions, Splices, Build-Ups, and Overdriving of Precast Concrete Pile:
a.The Engineer shall approve all extensions, build-ups, or splices on concrete piles. When authorized, they shall be made as follows:
1.After driving is completed, the concrete at the end of the pile shall be cut away leaving the reinforcing bars exposed for 20 inches (500 mm).
2.The cut of the concrete shall be perpendicular to the axis of the pile.
3.Additional bars of the same size and number as original bars, together with spiral reinforcing, shall then be fastened securely to the projecting steel and the necessary formwork placed. Formwork shall be built to prevent leakage along the pile.
4.The concrete shall be of the same mix as that used in the original pile.
5.Just before placing concre te, the top of the pile shall be thoroughly wetted and covered with a thin coating of mortar (1 part cement and 2 parts fine aggregate for concrete).
6.The forms shall remain in place until test cylinders made during the progress of the work and subjec ted to the same curing conditions have attained a compressive strength of at least 2,000 psi (14 MPa).
b.A driving splice may be constr ucted instead of a build-up splice. The steel sleeve shall be fitted over t he top of the driven pile, and a length of the same type of piling shall be placed in the top section of the sleeve. The piling shall be seated together by short blows with the hammer before full driving forces are applied. The allo wable length of the extension will be determined by the Engineer.
9.Prefabricated Cast Steel Pile Points:
a.Piles requiring prefabricated pile point protection are shown in the contract.
b.The piles shall be cut off to provide a good fit with the prefabricated point.
c.Flanges shall be beveled 0. 3 inch (8 mm) to prepare for the attaching welds, and the points shall be at tached to the pile by an 0.3 inch (8 mm) (minimum) single bevel groove weld across the full wi dth of the pile flanges.
10.Painting: a. Exposed surfaces of all piles above finished ground line or stream shall be painted. Piles and Pile Driving 703.05 - 477 - b. Steel bearing piles, steel pile shells, pipe piles, and steel sheet piles shall be painted in accordance with the requirements of Section 709.
703.04 Method of Measurement
1.The unit of measurement for bearing piling will be the linear foot (meter). The quantity shall be the authoriz ed length of piles in the completed structure.
2.Sheet piling will be measured for payment by the square foot (square meter). The area is obtained by multiplying the length of the sheets driven by the manufacturer's nominal driving width of each sheet. The quantity paid will be the aut horized square feet (square meter) of sheet piling in the completed structure.
3."Test Pile" are measured by the each.
4.A pile allowance is not authorized for quantities greater than those ordered by the Engineer or for piles subs idiary to other items of work (i.e., test piles).
5.All cutoff material shall become the property of t he Contractor and shall be disposed of in a manner satisfactory to the Engineer.
703.05 Basis of Payment 1. P a y I t e m P a y U n i t
T e s t P i l e _ _ _ _ _ E a c h ( e a ) Concrete _____ Piling Linear Foot (LF) [Meter (m)] Pipe Piling Linear Foot (LF) [Meter (m)] _____ inch x _____ lb Steel Piling Linear Foot (LF) [Meter (m)] Steel Sheet Piling Square Foot (SF) [Square Meter (m 2)] S t a t i c P i l e L o a d T e s t E a c h ( e a )
2.a. (1) Provided that the C ontractor furnishes the Engineer signed purchase orders for bearing and sheet piling, authorized “cutoff” of bearing and sheet piling shall be made at the invoice price per linear foot (meter) of piling.
2.The signed purchase orders shall be furnished at the pre-construction conference.
b.In those cases where signed purchase orders for bearing and sheet piling are not furnished at the pre-construction conference, authorized “cutoff” of bearing and sheet piling sh all be made at 60% of the piling’s contract unit price.
c.No payment is made for “c utoff” beyond the order length.
d.When bearing or sheet pile are authorized for cutoff and are suitable for use as spliced material for the same purpose on the project, the length of material subsequently driven as service piling shall be deducted
703.05 Piles and Pile Driving
- 478 - from the payment for cutoff. No piece of piling can q ualify for more than one measurement as pay cutoff.
3.Splices ordered by the Engineer shall be paid for at 5 times the unit bid price (2 times the unit bid price for Metric projects) for HP steel piling, pipe piling, and cast-in-place piling; and at 20 times the unit bid price (7 times the unit bid price for Metric projects) for driving and build-up splices for precast/prestressed concrete piling.
4.Separate payment, at the contract unit price, is provided for piling extensions needed to reach cutoff elevation, bearing capacity, and/or practical refusal.
5.Unless a soil-setup is specified on the contract, all pile soil-setup factors ordered by the Engineer will be paid for at a rate of $750.00 each. Multiple soil-setup factors taken for any one group and within one hour of each other will be considered one soil- setup factor, and payment will be a total of $750.00.
6.The work performed by the Contra ctor in conjunction with the use of the Department's Pile Driving Analyz er shall be considered subsidiary to the piling.
7.Overdriving:
a.A pile is overdriven when the Engineer determines that the pile must be driven deeper than the specif ied depth and no extension to the order length is necessary.
b.Overdriving length is paid fo r at 40% of the contract unit price of the piling.
c.Payment length shall be the difference between the original cutoff elevation and the actual elevation of the top of the pile in-place in the structure.
d.Additional concrete required, due to the void from the precast concrete piles, will be paid at the invoice price.
8.Furnishing and attaching cast steel pile points will not be paid for directly but shall be considered subsidiary to the piling.
9.Pile jetting or augering is a Contractor's option and shall be performed at no additional cost to the Department.
10.Optional field splices are subsidiary to the pile payment. 11. The pile used in the pay item "Test Pile _____" is subsidiary to this pay item.
12.The Contractor shall replace and redrive broken or damaged cast- in-place concrete pile shells at no additional cost to the Department.
13.The Contractor shall remove and replace piles that are broken or damaged at no additional cost to the Department.
14.No payment will be made for broken piles or piles that are ordered and are not used.
15.Payment is full compensation for all work described in this Section. - 479 - SECTION 704 -- CONCRETE CONSTRUCTION
704.01 Description
1.This work shall consist of fa lsework and form construction and the handling, placing, curing, and finishing of concrete for bridges, box culverts, arch culverts, headwalls, concrete seals, retaining walls and steps, foundations, substructures, and miscella neous structures. All work shall be done in accordance with these S pecifications and the contract.
2.Also included in this Section is all work necessary to adapt existing structures for extension or reconstruction.
704.02 Material Requirements
1.The class of concrete shall be sh own in the contract or specified in the special provisions.
2.When the contract or special pr ovisions allow the use of more than one class of concrete, the Contractor sh all advise the Engineer of the class of concrete to be used before the date of beginning of concrete construction on any project. No change shall be made in the class of concrete during the progress of the work without the written permission of the Engineer.
3.Materials shall conform to the requirements in Table 704.01. Table 704.01 Material Requirements Applicable Materials Section Anchor Bolts ..................................................... .1057, 1058 Curing Ma terials ................................................ .1010, 1011, 1012 Deformed Metal Center Joints and Metal Ke yway ................................................... . Dowel Ba rs ....................................................... .1022 Galvanized Ha rdware ....................................... .1059 Joint Sealing Filler ............................................. .1014 Paint and Pain t Materials .................................. .1077 Portland Cement Concrete ............................... .1002 Preformed Jo int Filler ........................................ .1015 Reinforcing Steel ............................................... .1020, 1023, 1024 Epoxy Coated Rein forcing Steel ....................... .1021 Structural Steel ................................................. . 708
704.03 Construction Methods
1.The Contractor shall construct c oncrete structures as described in the contract. All concrete rails on bridges and approach slabs shall be cast- in-place. Slip-forming will not be permitted for concrete rails on bridges and approach slabs.
2.Foundation Preparation:
a.Foundation excavations shall be as dry as practicable before concrete is placed.
b.In the event that the Contractor is required to excavate for spread footings to depths greater t han those shown in the contract, the Engineer will redesign the structure' s outline and reinforcement and provide the Contractor the appropriate revised plans.
Source: Nebraska Standard Specifications for Highway Construction, 2017 Edition. Pages 499–512 of 1,048.