504Bearing Piles and Sheet Piling

Bearing Piles and Sheet Piling

504.1DESCRIPTION

1 This section describes the requirements for furnishing and driving steel bearing piles and steel sheet piling.

504.2MATERIALS

1 Provide materials in accordance with the following:

Material Subsection Steel Piles 815.7 Cutwater Angles and Pile Splices 815.1 Paint 809 Sheet Piling 815.8

2 Ensure that sheet piling has a minimum section modulus (SM), (in3/ft [cm3/m]) as specified.

504.3EQUIPMENT

504.3.1 Pile Driving for Bearing Piles

1 Provide hammers capable of driving piles to specified length and required bearing capacity.

2 Use fixed or swinging leads constructed to allow free movement of the hammer and rigged to hold the pile and hammer in alignment during driving. To distribute the hammer blow, fit a helmet around the pile head as needed to prevent the transfer of torsional forces during driving; maintain the proper hammer and pile alignment. Provide hammer cushions of durable manufactured materials in accordance with the hammer manufacturer’s guidelines. Equip diesel hammers with a device, such as rings on the ram, that allows the engineer to visually determine hammer stroke at all times during pile driving.

3 Do not use gravity pile hammers. The engineer may approve the use of air, steam, hydraulic, or closed end diesel hammers.

4 Submit hammer specifications to the engineer, including the following information:

of the pile hammer;

Bearing Piles and Sheet Piling SECTION 504

elastic modulus in kips per square inch [megapascals], and coefficient of restitution of cushioning material;

5 When the department requires dynamic pile testing, supply an electrical generator capable of producing 1 kW of power to operate the testing equipment.

504.3.1.1 Approval of Pile-Driving Equipment

1 The Geology Program will determine the adequacy of the pile hammer through wave equation analysis. If the hammer is deemed inadequate, provide other equipment. At least 14 calendar days before driving piles, using the “Pile Driving Hammer Configuration” (Form E-74A) give the engineer the data for each hammer to be used. The department will not allow the use of hammers for which the wave equation indicates pile stresses that exceed 90 percent of the minimum yield strength for steel piling.

504.3.2 Pile Driving for Sheet Piling

1 Use a vibratory hammer to drive sheet piling unless otherwise approved in writing by the engineer.

504.4CONSTRUCTION

504.4.1 Determination of Length

1 Use bearing piles long enough to provide the specified bearing capacity, penetration, and extension into the cap or footing block. The length of piling specified is an estimate only.

2 For sheet piling, provide the specified area indicated on the department’s ““Proposal” (Form E-91), unless site conditions prevent installation to those limits. Proposal ” (Form E- 91), unless site conditions prevent installation to those limits.

504.

4.2Predrilled Holes

1 When specified or approved by the engineer, use predrilled holes. Extend to the elevation specified and obtain the remaining penetration with the pile driver. Do not allow the hole diameter to exceed the pile width. Place the pile in the hole and drive it to set the point firmly into bearing material, and secure full bearing. Fill the space around the pile to the

Bearing Piles and Sheet Piling SECTION 504

ground surface with dry sand, pea gravel, flowable fill, or other material approved by the engineer. Do not use water or air jets without written approval from the engineer.

504.4.3 Pile Driving

except with the engineer’s written approval. The engineer will consider changes in the driving system only after the necessary i nformation for a revised wa ve equation analysis is submitted. Support long piles to prevent lateral buckling during driving.

Support pile hammers in leads while driving piles. Maintain hammers to obtain the operating length of the stroke and number of blows per minute for which the hammer is designed. Maintain cushions in good condition. The engineer will observe the hammer’s initial operations to verify its adequac y. Repair or replace inadequate hammers.

Cut the heads of steel piles squarely. Ensure that the helmet closely fits the top of the pile and extends down the sides to maintain alignment of the pile head under hard driving conditions.

Drive piles to within ¼ in/ft [20 mm/m] of vertical or the specified batter. Drive foundation piles in footings of piers and abutments so that their tops are within 6 in [150 mm] of position in any direction.

1.1Pile Bents. Drive piles for bents so that the center of each pile’s top is within

6 in [150 mm] of that specified when measured parallel to the centerline of the bent.

1.

For pile bents with steel bent caps, ensure that the centerline of the

tops of the piles is not out of position by more than 2 in [50 mm] measured perpendicular to the specified centerline of the bent or more than 1 in [25 mm] from a stringline stretched between the centerline of the exterior piles.

1.1.2For pile bents with concrete bent caps, ensure that the centerline of

the tops of the piles is not out of position by more than 3 in [75 mm] measured perpendicular to the specified centerline of the bent.

When specified, cut weep holes at the factory or in the field.

504.4.4 Bearing Value and Penetration for Bearing Piles

1 Drive pile to the length specified and at least 12 ft [4 m] into the ground when no tip elevation is specified. The department defines ground within an area of roadway

Bearing Piles and Sheet Piling SECTION 504

embankment as the bottom of the roadway embankment or bottom of footing, whichever is lower. When a tip elevation is specified, drive piles to at least the specified elevation, unless otherwise allowed in writing by the engineer.

engineer will provide the following:

The stroke or hammer energy;

1.2The blow count criteria to prevent overstressing of piling; and

1.3The amount of pile “set” in blows per inch [mm] to achieve refusal at a

specified stroke or hammer energy for open end diesel hammers or hydraulic hammers respectively.

resistance factor, the engineer will provide the blow count per inch [mm] or per 12 in [300 mm] at a specified stroke or hammer energy to achieve design bearing capacity and to prevent overstressing of piling.

2.1Dynamic Load Tests. If specified, the department will take dynamic load

measurements. Before full production driving, drive test piling; the department will specify pile locations to be tested. Contact the engineer 14 calendar days before and again two days before installing test piles. The department will schedule a testing consultant to instrument and test piles during driving. The department’s consultant will test using the pile dynamic analyzer with the Case Pile Wave Analysis Program to determine when the desired load capacity is achieved.

When specified, restrike a minimum of 24 hours after the test pile has been driven to ensure the desired capacity has been achieved. Do not drive any additional pile until the restrike has been completed and the capacity of the test pile has been verified.

Allow sufficient time for required instrumentation and testing. Delay or standby time resulting from nonadherence of the contractor to the pile testing schedule will be at no additional cost to the department.

Provide an additional 10 ft [3 m] of piling for testing. The department may change the specified length of piles driven after the tests.

504.4.5 Cutoff

1 Cut steel piles off at the elevation specified and, when required, cap them with steel plates or other devices. Cut sheet piles off at the depth specified.

Bearing Piles and Sheet Piling SECTION 504

504.4.6 Pile Splices

1 Use steel piling of the size and weight [mass] specified. The department will allow the length of steel pile to be built up in sections by splicing. Splice before driving, during driving, or both. Ensure that spliced piles have identical cross-sections.

2 Make steel pile splices with pile splicer sections or welded splices as follows:

cut a ⅞ in × 2⅛ in [22 mm × 54 mm] notch in the web for the spacer bar. Slip the splicer onto the upper pile until the bar slides into the notch, then weld the splicer to the upper pile. Set the upper pile with the attached splicer on the driven pile. Weld the splicer and the outside edge of each flange to the driven pile.

3 Align the connected pile sections to ensure that the axis of the pile is straight. Weld splices in accordance with Subsection 501.4.2.5, Field Welding. Do not use a pile splicer section when the splice point is above ground unless piling is embedded in concrete.

4 All pile splices must be at least 6 ft [2 m] below the bottom of the pile cap.

504.4.7 Painting

1 Paint piles that will be visible in the completed structure. Clean and paint the exposed portion of the pile and the portion extending 24 in [600 mm] below ground or low water surface, whichever is higher, in accordance with Subsection 501.4.2.8, Field Painting. For the final coat, use the color specified.

504.

4.8Pile Points

1 Use and attach pile points as specified. Work necessary for pile points is considered incidental to the steel piling.

504.5MEASUREMENT and PAYMENT

1 The engineer will measure:

lengths per each; splices made for the contractor’s convenience will not be paid for. Only one splice per pile will be paid for when an overrun in the specified length occurs.

Bearing Piles and Sheet Piling SECTION 504

the length of a pile point.

2 When the total driven quantity of piling installed is less than the total contract quantity, the department will pay the di fference by the invoice price of the material and the transportation cost. Excess piling remains the property of the contractor.

3 If required by the engineer, he or she will measure piling installed in excess of the total contract quantity for payment.

4 The department will pay as follows:

Pay Item

Pay Unit Measure to the Nearest Pay to the Nearest Pile Splices EA [Ea] EA [Ea] EA [Ea] Predrilled Holes FT [m] 0.1 ft [0.05 m] FT [0.5 m] Steel Piling HP × FT [m] 0.1 ft [0.05 m] FT [0.5 m] Steel Sheet Piling (SM ) SF [m2] 0.1 ft [0.05 m] SF [0.1 m2]