31 41 16.pdf

Charleroi Locks and Dam - Upper and Lower Guard Walls

SECTION TABLE OF CONTENTS

DIVISION 31 - EARTHWORK

SECTION 31 41 16

METAL SHEET PILING

PART 1 GENERAL

1.1 REFERENCES

1.2 SUBMITTALS

1.3 DELIVERY, STORAGE AND HANDLING

1.4 QUALITY ASSURANCE

1.4.1 Material Certificates

1.5 EQUIPMENT

1.6 SUPERVISION, INSPECTION, AND SAFETY

1.6.1 Supervision

1.6.2 Inspection

1.6.3 Safety

1.7 GEOLOGIC INVESTIGATIONS AND PREREQUISITE EXPLORATORY DRILLING

1.7.1 Geologic Investigations and Prerequisite Testing

1.7.2 Inspection of Geologic Samples

1.7.3 Interpretation of Geologic Information, Data and Samples

1.7.3.1 Ordering of Piles

PART 2 PRODUCTS

2.1 GOVERNMENT-FURNISHED METAL SHEET PILING

2.1 METAL SHEET PILING

2.2 Interlocks

2.3 General Requirements

2.4 APPURTENANT METAL MATERIALS

2.5 TESTS, INSPECTIONS, AND VERIFICATIONS

2.5.1 Materials Tests

PART 3 EXECUTION

3.1 EARTHWORK

3.2 PILE DRIVING EQUIPMENT

3.2.1 Driving Helmets and Pile Cushions

3.2.2 Pile Driving Leads

3.2.3 Pile Extractors

3.2.4 Followers

3.2.5 Guide Template

3.3 INSTALLATION

3.3.1 General

3.3.2 Alignment

3.3.3 Damaged Piles

3.3.4 Lengths of Permanent Piles

3.3.5 Placing and Driving

3.3.5.1 Placing

3.3.5.2 Driving

3.3.6 Refusal

SECTION 31 41 16 Page 1 W911WN-09-B-0004 Revised by Amendment No. 0002

3.3.7 Cutting-Off and Splicing

3.4 TOLERANCES

3.4.1 General

3.4.2 Control of Alignment and Size

3.5 QUANTITIES

3.6 INSTALLATION RECORDS

3.7 SPECIAL REQUIREMENTS FOR MEMBERS TO BE FURNISHED BUT NOT ERECTED

3.8 CONTRACTOR QUALITY CONTROL

3.8.1 Contractor Quality Control

3.8.2 Inspection of Driven Piling

3.8.3 Pulling and Redriving

3.8.4 Inspection Reports

3.9 RETURN OF UNUSED GOVERNMENT-FURNISHED PILING

3.9.1 Sorting, Cleaning, Inventorying and Storing

-- End of Section Table of Contents --

SECTION 31 41 16 Page 2

SECTION 31 41 16

METAL SHEET PILING

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AMERICAN WELDING SOCIETY (AWS)

AWS D1.1/D1.1M (2008) Structural Welding Code - Steel

ASTM INTERNATIONAL (ASTM)

ASTM A 328/A 328M (2007) Standard Specification for Steel Sheet Piling

ASTM A 572/A 572M (2007) Standard Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel

ASTM A 6/A 6M (2007) Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, and Sheet Piling

ASTM A 690/A 690M (2007) Standard Specification for High-Strength Low-Alloy Nickel, Copper, Phosphorus Steel H-Piles and Sheet Piling with Atmospheric Corrosion Resistance for Use in Marine Environments

THE SOCIETY FOR PROTECTIVE COATINGS (SSPC)

SSPC Paint 22 (1982; E 2004) Paint Specification No. 22 Epoxy-Polyamide Paints (Primer, Intermediate, and Topcoat)

U.S. ARMY CORPS OF ENGINEERS (USACE)

EM 385-1-1 (2008) Safety -- Safety and Health Requirements

1.2 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. The following shall be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-02 Shop Drawings

SECTION 31 41 16 Page 3

Metal Sheet Piling; G, RE

Detail drawings for Government-furnished and Contractor-furnished sheet piling, including fabricated sections, shall show complete piling dimensions and details, driving sequence and location of installed piling. Detail drawings shall include details of top protection, special reinforcing tips, tip protection, lagging, splices, fabricated additions to plain piles, cut-off method, corrosion protection, and dimensions of templates and other temporary guide structures for installing piling.

Detail drawings shall provide details of the method of handling piling to prevent permanent deflection, distortion or damage to piling interlocks.

SD-03 Product Data

Driving

Records of the completed sheet piling driving operations. These records shall provide a system of identification which shows the disposition of approved piling in the work, driving equipment performance data, piling penetration rate data, piling dimensions and top and bottom elevations of installed piling, the sheet pile tip elevation at vibratory refusal and the sheet pile tip at driven refusal. The Contractor shall utilize the sample "Pile Driving Record" attached to the end of this Section of the Specifications.

Pile Driving Equipment; G, ED

Complete descriptions of sheet piling driving equipment including hammers, extractors, protection caps and other installation appurtenances, prior to commencement of work. Submit the following information for each impact hammer proposed:

a. Make and model.

b. Ram weight (pounds).

c. Anvil weight (pounds).

d. Rated stroke (inches).

e. Rated energy range (foot-pounds).

f. Rated speed (blows per minute).

g. Steam or air pressure, hammer, and boiler or compressor (psi).

h. Pile driving cap, make, and weight (pounds).

i. Cushion block dimensions and material type.

j. Power pack description.

Pulling and Redriving; G, RE

SECTION 31 41 16 Page 4

The proposed method of pulling sheet piling, prior to pulling any piling.

SD-06 Test Reports

Materials Tests

Certified materials tests reports. Reports showing that sheet piling and appurtenant metal materials meet the specified requirements shall be submitted for each shipment and identified with specific lots prior to installing materials. Material test reports shall meet the requirements of ASTM A 6/A 6M.

SD-11 Closeout Submittals

Pile Driving Record

Record for each sheet pile driven, as specified.

1.3 DELIVERY, STORAGE AND HANDLING

Contractor-furnished materials delivered to the site shall be new and undamaged and shall be accompanied by certified test reports. The manufacturer's logo and mill identification mark shall be provided on the sheet piling as required by the referenced specifications. All sheet piling shall be stored and handled in the manner recommended by the manufacturer to prevent permanent deflection, distortion or damage to the interlocks; as a minimum, support on level blocks or racks spaced not more than 10 feet apart and not more than 2 feet from the ends. Storage of sheet piling should also facilitate required inspection activities and prevent damage to coatings and corrosion prior to installation. Sheet piling over 80 feet in length shall be handled using a minimum of two pickup points.

1.4 QUALITY ASSURANCE

1.4.1 Material Certificates

For each shipment, submit certificates identified with specific lots prior to installing piling. Identification data should include piling type, dimensions, chemical composition, mechanical properties, section properties, heat number, and mill identification mark.

1.5 EQUIPMENT

Submit descriptions of pile driving equipment to be employed in the work to the Contracting Officer for approval. Descriptive information includes manufacturer's name, model numbers, capacity, rated energy, hammer details, cushion material, helmet, templates, and jetting equipment.

1.6 SUPERVISION, INSPECTION, AND SAFETY

1.6.1 Supervision

The Contractor shall provide for the supervision of all phases of pile installation. Overall supervision of the work shall be the Contractor's responsibility and shall be considered a function of the Contractor's CQC program as outlined in Section 01 45 01 USACE QUALITY CONTROL.

SECTION 31 41 16 Page 5

1.6.2 Inspection

The Contractor shall provide for all CQC inspection of all pile installation. Overall inspection of the work shall be the Contractor's responsibility and shall be considered a function of the Contractor's CQC program as outlined in Section 01 45 01 USACE QUALITY CONTROL. Each aspect of the operation shall be checked by the Contractor's CQC staff for conformance with all tolerances required by the drawings and these specifications.

The Contracting Officer will also inspect the work for conformance with the requirements. The Contractor shall provide the Contracting Officer access and use of all instruments which are used to ascertain the alignment, plumb and any other devices which would assist the Contracting Officer in the inspection of the piles.

1.6.3 Safety

All work shall be conducted in accordance with EM 385-1-1.

1.7 GEOLOGIC INVESTIGATIONS AND PREREQUISITE EXPLORATORY DRILLING

1.7.1 Geologic Investigations and Prerequisite Testing

The Government has performed an exploratory drilling program. Logs of various core borings are provided within the set of contract drawings. The tip elevations for the sheet piles have been estimated from this exploratory program and the available core boring information.

The Contractor shall perform pile driving tests in accordance with Section 02 32 13.11 EXPLORATORY PILE DRIVING. Actual pile lengths for ordering sheet piles shall be determined from the exploratory pile driving tests specified in Section 02 32 13.12 EXPLORATORY PILE DRIVING.

1.7.2 Inspection of Geologic Samples

Core samples from the site are available for inspection in accordance with SECTION 01 30 00.10 GENERAL REQUIREMENTS, paragraph "INSPECTION OF GEOLOGIC

SAMPLES".

1.7.3 Interpretation of Geologic Information, Data and Samples

Subsurface records are included with the contract drawings. Logs of borings and test data are made available for the Contractor's information and for his interpretation. Logs and test data are not represented as a complete description of the site soil, rock, and water information, but only display what was found in borings at the indicated locations on the date holes were drilled. The soil and groundwater conditions may be different from those interpreted by the subsurface investigation. The Contractor has the right to obtain additional information, if necessary in his judgment.

1.7.3.1 Ordering of Piles

Quantities and necessary equipment, for bidding purposes, shall be based on the dimensions indicated on the contract drawings. Actual orders of sheet piles shall be restricted as follows:

The Contractor shall order sheet piles in conjunction with the completion

SECTION 31 41 16 Page 6 of an exploratory pile-driving program as described in Section 02 32 13.12 EXPLORATORY PILE DRIVING. All sheet piles shall be ordered AFTER the exploratory pile-driving program is completed along wall alignment. The Contractor assumes all risk for materials that are ordered prior to being released by the Contracting Officer. No additional payment will be made for splices, cutoff or reorders resulting from premature order of the materials. All costs for such work for materials incorrectly ordered shall be at the Contractor's expense, at no cost to the Government.

PART 2 PRODUCTS

2.1 GOVERNMENT-FURNISHED METAL SHEET PILING

The Government has purchased metal sheet piling for construction of closures, Upper Guard Wall Nose Cell, Lower Guard Wall cells, and the Downstream Protection Cell, as specified in Section 01 30 00.10 GENERAL REQUIREMENTS, paragraph GOVERNMENT-FURNISHED PROPERTY. This piling has been purchased longer than the anticipated length required to allow for determination of actual required length in accordance with paragraph "Lengths of Permanent Piles". The following sheet piling has been stored at the Victory Hollow site:

1. Lower Guard Wall -- 252 Sheets of Metal Sheet Piling: PS 31, ASTM A 572/A 572M, Grade 50, 69.569 ft. long, hot-rolled, sheets.

Sheets are painted with epoxy primer and two-coat abrasion-resistant epoxy paint system

2. Upper Guard Wall -- 104 Sheets of Metal Sheet Piling: PS 31, ASTM A 572/A 572M, Grade 50, 69.569 ft. long, hot-rolled, sheets.

Sheets are painted with epoxy primer and two-coat abrasion-resistant epoxy paint system

The painted piling is coated with a ferrous metal primer conforming to SSPC Paint 22 similar to BAR RUST 235, as manufactured by DEVOE Coatings Company, and two coats of abrasion resistant epoxy coating similar to DEVGRIP 238, as manufactured by DEVOE Coatings Company. The dry film thickness of each abrasion resistant epoxy coating is approximately 10 mils. No fabricated piling will be furnished by the Government. Any fabricated piles shall be fabricated by the Contractor using the Government-furnished piling.

The Contractor shall be responsible for furnishing all equipment, labor, and supplies required for loading the materials at the storage site, transporting the materials to the project, and installing the materials as shown on the drawings and as specified.

2.1 METAL SHEET PILING

Metal sheet piling shall be hot-rolled steel sections conforming to ASTM A 328/A 328M, ASTM A 572/A 572M, Grade 50, and ASTM A 690/A 690M, as applicable.

2.2 Interlocks

The interlocks of sheet piling shall be free-sliding, provide a swing angle suitable for the intended installation but not less than 5 degrees when interlocked, and maintain continuous interlocking when installed.

SECTION 31 41 16 Page 7

2.3 General Requirements

Based on the results of the exploratory drilling, as required in Section 02 32 13.11 EXPLORATORY DRILLING, and exploratory pile driving, as required in Section 02 32 13.12 EXPLORATORY PILE DRIVING, the tip elevations of the piling will be known fairly accurately. This will allow the sheet piling to be cut to the proper length and any fabrications to occur at the proper location prior to driving. Sheet piling including special fabricated sections shall be full-length sections of the dimensions shown. Fabricated sections shall conform to the requirement and the piling manufacturer's recommendations for fabricated sections. Fabricated sections connecting cofferdam cells and adjacent arcs composed of pilings from different manufacturers shall be Wye-sections fabricated from the respective manufacturer's pilings. Fabricated tees, wyes and cross pieces shall be fabricated of piling sections with a minimum web thickness of 1/2 inch.

Sheet piling to be placed in a circular cell or a connecting arc shall be of the same manufacture. Sheet piling shall be provided with standard pulling holes. Metalwork fabrication for sheet piling shall be as specified and in Section 05 50 14 STRUCTURAL METAL FABRICATIONS.

Special and custom sheet pile cross sections and shapes shall be fabricated as shown on the drawings, accounting for actual existing field conditions.

The Contractor shall verify all critical existing field conditions and dimensions prior to fabricating special and custom sheets. Any connections required to fabricate special and custom sections and shapes shall be bolted connections in accordance with the sheet pile manufacturer's recommendations. All cut edges, bolt holes and areas where the existing coating is damaged shall be cleaned and painted with coating equivalent to the existing. Surface preparation shall be recommended by the coating manufacturer.

2.4 APPURTENANT METAL MATERIALS

Metal plates, shapes, bolts, nuts, sheet pile connectors, and other appurtenant fabrication and installation materials shall conform to manufacturer's standards and to the requirements specified in the respective sheet piling standards and in Section 05 50 15 CIVIL WORKS

FABRICATIONS.

2.5 TESTS, INSPECTIONS, AND VERIFICATIONS

Requirements for material tests, workmanship and other measures for quality assurance shall be as specified and in Section 05 50 14 STRUCTURAL METAL FABRICATIONS. Testing requirements apply only to piling furnished by the Contractor.

2.5.1 Materials Tests

Materials tests shall conform to the following requirements. Sheet piling and appurtenant materials shall be tested and certified by the manufacturer to meet the specified chemical, mechanical and section property requirements prior to delivery to the site. Testing of sheet piling for mechanical properties shall be performed after the completion of all rolling and forming operations. Testing of sheet piling shall meet the requirements of ASTM A 6/A 6M, including weldability requirements.

SECTION 31 41 16 Page 8

PART 3 EXECUTION

3.1 EARTHWORK

Perform in accordance with Section 35 20 23.10 DREDGING AND UNDERWATER EXCAVATION. Pre-excavation will be permitted as indicated.

3.2 PILE DRIVING EQUIPMENT

The Contractor shall select the proposed pile driving equipment, including hammers and other required items, and submit complete descriptions of the proposed equipment in accordance with paragraph SUBMITTALS. Final approval of the proposed equipment and accessories are subject to the satisfactory completion and approval of the exploratory pile driving tests per Section 02 32 13.12 EXPLORATORY PILE DRIVING) and completion of the exploratory drilling program per Section 02 32 13.11 EXPLORATORY DRILLING. Changes in the selected pile driving equipment will not be allowed after the equipment has been approved except as directed. No additional contract time will be allowed for Contractor proposed changes in the equipment. Remedial action due to failure of the Contractor's hammer equipment to satisfy the requirements and achieve the specified results will be at the Contractor's expense. Such remedial action may consist of, but need not be limited to, adjustment or replacement of hammer cushion and/or follower, or of pile cushion, or to adjustment or replacement of hammer.

The Contractor shall utilize the results of the Government-performed and Contractor-performed exploratory pile driving program, (See Section Section 02 32 13.12 EXPLORATORY PILE DRIVING), the boring logs and the results of the Contractor-performed Exploratory drilling program (See Section 02 32 13.11 EXPLORATORY DRILLING) to determine the type and size of equipment to be employed. Vibratory hammers shall be used to advance the piles and obtain an elevation of vibratory refusal, but final seating into rock to reach the specified embedments shall be performed using impact equipment. Vibratory hammers shall provide for maintaining a rigid connection between the hammer and the pile. Impact hammers shall be steam, air, or diesel hammers of the single acting, double-acting, or differential acting type. The impact hammer used shall have a delivered energy suitable for the total weight of the pile, the character of subsurface material to be encountered, and the pile capacity to be developed. The size or capacity of hammers shall be as recommended by the manufacturer for the pile type and weight, soil type, driving configuration, and subsurface conditions to be penetrated. Hammers shall be capable of, and so demonstrated during the development of refusal criteria, sustained hard driving in excess of 20 blows per inch at the normal working rate. Boiler, compressor, or engine capacity shall be sufficient to operate hammers continuously at the full rated speed. Hammers shall have a calibrated pressure gauge on the hammer side of all valves to monitor hammer bounce chamber pressure for diesel hammers or pressure at the hammer for air and steam hammers. This gauge shall be operational during the driving of piles and shall be mounted in an accessible location for monitoring by the Contractor and the Contracting Officer.

3.2.1 Driving Helmets and Pile Cushions

A driving helmet or cap, including a pile cushion, shall be used between the top of the pile and the ram to prevent impact damage to the pile. The driving helmet, or cap and pile cushion combination, shall be capable of protecting the head of the pile, minimizing energy absorption and dissipation, and transmitting hammer energy uniformly over the top of the

SECTION 31 41 16 Page 9 pile. The driving helmet or cap shall fit loosely around the top of the pile so that the pile is not restrained by the driving cap if the pile tends to rotate during driving. The pile cushion may be made of solid wood or of laminated construction using plywood, softwood, or hardwood boards or other cushion material as approved by the Contracting Officer. The pile cushion shall completely cover the top surface of the pile and shall be retained by the driving helmet. The minimum thickness of the pile cushion shall be 3 inches and the thickness shall be increased so as to be suitable for the size and length of pile, character of subsurface material encountered, hammer characteristics, and required driving resistance.

3.2.2 Pile Driving Leads

Impact hammers shall be supported and guided with fixed extended leads or fixed underhung leads. Two intermediate supports for the follower in the leads shall be provided to reduce the unbraced length of the follower-pile system during driving and pulling.

Leads and follower shall allow the impact hammer to deliver impacts concentrically and in alignment with the pile longitudinal axis without inducing bending moment in the pile. Leads shall be fixed and shall be supported near the top and bottom. Leads shall be of sufficient length to accommodate the combined length of the follower and hammer. Performance of the leads will be subject to assessment of the Contracting Officer during the pile tests. Any remedial action required will be at the Contractor's expense.

3.2.3 Pile Extractors

Pile extractors may be vibratory and/or impact pile driving hammers. Impact hammers will be required for pulling piles that are not extractable with vibratory hammers.

3.2.4 Followers

Followers will be permitted if it is an accepted component of the Government-approved Installation Plan. Followers shall provide a constant dynamic impedance (EA/c) equal to that of the pile and of a shape and length enabling driving of the pile at the specified location and to the required depth and resistance. Followers shall be provided with a socket or hood which is carefully fitted to the pile cap to minimize loss of energy and prevent damage to the pile. The follower to be used on production king piles, corner piles and sheet piles shall be the same used for the exploratory test piles (per Section Section 02 32 13.12 EXPLORATORY PILE DRIVING). Proper design and performance of the follower shall be subject to the assessment of the Contracting Officer. Any subsequent remedial action will be at the Contractor's own expense.

3.2.5 Guide Template

The Contractor shall provide a fixed guide template for pile installation.

The template shall be designed by the Contractor and shall be suitably rigid to maintain the locations, relative positions and alignment of two or more adjacent piles during installation. The Contractor shall supply all materials and fabricate the template. The template shall remain the Contractor's property after completion of the pile installation and shall be removed from the site. The Contractor's design shall ensure that the template is movable and can be adjusted to accurately place the piles within the tolerances specified.

SECTION 31 41 16 Page 10

3.3 INSTALLATION

3.3.1 General

Pile driving shall conform to the requirements herein. Prior to installing piling, the Contractor shall submit a pile installation plan detailing the proposed methods for installing the piling. Piles shall not be driven within 50 feet of recently placed concrete that has not attained a strength of at least 2,000 psi. Hammers shall be operated at all times at the speed and under the conditions recommended by the manufacturer. Prior to driving and with the pile head (or follower, as applicable) seated in the hammer, each pile shall be checked to ensure that it has been aligned correctly.

Once pile driving has begun, conditions such as alignment shall be kept constant. Each pile shall be driven continuously and without interruption until the required depth of penetration has been attained. Deviation from this procedure will be permitted only when driving is stopped by causes that reasonably could not have been anticipated. A pile that cannot be driven to the required depth because of an obstruction shall be drilled out to remove or displace the obstruction, or pulled and redriven. After piles are driven, they shall be cutoff square as required at the indicated cutoff elevation. Any voids around piles or remnant holes at the location of pulled piles shall be backfilled specifically with AASHTO size No. 8 granular material, and densified to the same density as the surrounding soil.

3.3.2 Alignment

Piles shall be placed accurately in the correct location and alignments, both laterally and longitudinally, and to the vertical lines indicated.

The Contractor shall establish a permanent base line to provide for inspection of pile placement by the Contracting Officer during pile driving operations. The base line shall be established prior to driving permanent piles and shall be maintained during the installation of the permanent piles. A final location and alignment of each pile shall be within the allowable tolerances specified in paragraph "TOLERANCES FOR PILES". The correct relative position of all piles shall be maintained by the use of a temporary guide template as described under paragraph "PILE DRIVING EQUIPMENT", or by other approved means. Any piles not meeting all tolerances shall be pulled and redriven at the location directed at no additional cost to the Government.

3.3.3 Damaged Piles

Piles damaged or impaired for use during driving shall be pulled and replaced with new piles without additional cost to the Government. The Contracting Officer may require that any pile be pulled for inspection.

Piles pulled as directed and found to be in suitable condition shall be redriven as directed. Piles pulled as directed and found to be damaged shall be replaced by new piles at the Contractor's expense.

3.3.4 Lengths of Permanent Piles

The estimated quantities of piles listed in the unit price schedule are given for bidding purposes only. The Contracting Officer will determine the actual tip elevations of piles for the various locations in the work from the exploratory pile driving (See SECTION 02 32 13.12 EXPLORATORY PILE DRIVING) and will furnish the Contractor a quantities list indicating tip elevations and locations of all piles to be installed.

SECTION 31 41 16 Page 11

3.3.5 Placing and Driving

3.3.5.1 Placing

Any excavation required within the area where sheet pilings are to be installed shall be completed prior to placing sheet pilings. Pilings properly placed and driven shall be interlocked throughout their length with adjacent pilings to form a continuous diaphragm throughout the length or run of piling wall.

a. Pilings to be placed in cells shall be picked up and completely threaded to demonstrate that they slide freely in interlock.

b. Pilings shall be carefully located as shown. Pilings shall be within the tolerances specified in paragraph "TOLERANCES" after driving.

c. Temporary wales, templates, master pilings or guide structures shall be provided to insure that the pilings are placed and driven to the correct alignment. Use a system of structural framing sufficiently rigid to resist lateral and driving forces and to adequately support the sheet piling until design tip elevation is achieved. At least two templates shall be used in placing each piling not less than 20 feet apart. Templates shall not move when supporting sheet piling. Fit templates with wood blocking to bear against the web of each alternate sheet pile and hold the sheet pile at the design location alignment.

Provide outer template straps or other restraints as necessary to prevent the sheets from warping or wandering from the alignment. Mark template for the location of the leading edge of each alternate sheet pile. If in view, also mark the second level to assure that the piles are vertical and in position. If two guide marks cannot be seen, other means must be used to keep the sheet pile vertical along its leading edge.

3.3.5.2 Driving

Prior to driving pilings in water, a horizontal line shall be painted on both sides of each piling at a fixed distance from the bottom so that it shall be visible above the water line after installation. This line shall indicate the profile of the bottom elevation of installed pilings and potential problem areas can be identified by abrupt changes in its elevation. Pilings shall be driven with the proper size hammer and by approved methods so as not to subject the pilings to damage and to ensure proper interlocking throughout their lengths.

a. Driving hammers shall be maintained in proper alignment during driving operations by use of leads or guides attached to the hammer.

Caution shall be taken in the sustained use of vibratory hammers when a hard driving condition is encountered to avoid interlock-melt or damages. The use of vibratory hammers should be discontinued and impact hammers employed when the penetration rate due to vibratory loading is one foot or less per minute.

b. A protecting cap shall be employed in driving when using impact hammers to prevent damage to the tops of pilings. Pilings damaged during driving or driven out of interlock shall be removed and replaced at the Contractor's expense. Government furnished pilings damaged during driving shall be returned to the storage site as directed.

SECTION 31 41 16 Page 12

c. Pilings shall be driven without the aid of a water jet.

d. Adequate precautions shall be taken to insure that pilings are driven plumb. Where possible, drive Z-pile with the ball end leading.

If an open socket is leading, a bolt or similar object placed in the bottom of the interlock will minimize packing material into it and ease driving for the next sheet. Any piles not meeting all tolerances shall be pulled and redriven at the location directed at no additional cost to the Government.

e. Pilings and pairs of piling in each run or continuous length of piling wall shall be driven alternately in increments of depth to the required depth or elevationuntil refusal has been reached. No piling or pair of piling shall be driven to a lower elevation than those behind it in the same run except when the pilings behind it cannot be driven deeper. Incrementally sequence driving of individual piles or pairs of piles such that the tip of any sheet pile shall not be more than 4 feet below that of any adjacent sheet pile. When the penetration resistance exceeds five blows per inch, the tip of any sheet pile shall not be more than 2 feet below any adjacent sheet pile. For cofferdam cells the driving increments shall be such that no piling leads the adjacent piling by more than 2 feet and the direction of advancing the driving hammer shall be reversed after each pass around the cell. If the piling next to the one being driven tends to follow below final elevation it may be pinned to the next adjacent piling.

f. If obstructions restrict driving a piling to the specified penetration the obstructions shall be removed or penetrated with a chisel beam. If the Contractor demonstrates that removal or penetration is impractical the Contractor shall make changes in the design alignment of the piling structure as directed to insure the adequacy and stability of the structure. Pilings shall be driven to depths shown and shall extend up to the elevation indicated for the top of pilings. Piling driven to rock shall be seated individually on the rock. At least the first two sheets of the connecting arcs adjacent to the main cells shall be driven in the cofferdam cells prior to filling the cells. Pilings shall not be driven within 100 feet of concrete less than 7 days old.

g. Pre-augering or spudding of piles will not be permitted.

3.3.6 Refusal

All PZ piling shall be driven to refusal into rock in pairs, all flat sheets shall be driven into rock individually. A piling shall be considered driven to refusal when refusal has been reached. Refusal is defined as 15 hammer blows per inch (bpi) or two consecutive inshes with counts of 10 bpi or higher using equipment meeting the requirements of paragraph "PILE DRIVING EQUIPMENT:, above.

3.3.7 Cutting-Off and Splicing

Pilings driven to refusal or to the point where additional penetration cannot be attained and are extending above the required top elevation in excess of the specified tolerance shall be cut off to the required elevation. Pilings driven below the required top elevation and pilings damaged by driving and cut off to permit further driving shall be extended

SECTION 31 41 16 Page 13 as required to reach the top elevation by splicing when directed at no additional cost to the Government. If directed, pilings shall be spliced as required to drive them to depths greater than shown and extend them up to the required top elevation.

a. Pilings adjoining spliced pilings shall be full length unless otherwise approved. If splices are allowed in adjoining pilings the splices must be spaced at least three feet apart in elevation.

Splicing of pilings shall be as indicated. Ends of pilings to be spliced shall be squared before splicing to eliminate dips or camber.

Pilings shall be spliced together with concentric alignment of the interlocks so that there are no discontinuities, dips or camber at the abutting interlocks. Spliced pilings shall be free sliding and able to obtain the maximum swing with contiguous pilings. Welding of splices shall conform to the requirements of Section 05 50 14 STRUCTURAL METAL FABRICATIONS. Shop and field welding, qualification of welding procedures, welders, and welding operators shall be in accordance with

AWS D1.1/D1.1M.

b. The tops of pilings excessively battered during driving shall be trimmed when directed, at no cost to the Government. Piling cut-offs except for Government furnished pilings shall become the property of the Contractor and shall be removed from the site.

c. The Contractor shall cut holes in pilings for bolts, rods, drains or utilities as shown or as directed. All cutting shall be done in a neat and workmanlike manner. A straight edge shall be used in cuts made by burning to avoid abrupt nicks. Bolt holes in steel piling shall be drilled or may be burned and reamed by approved methods which will not damage the surrounding metal. Holes other than bolt holes shall be reasonably smooth and the proper size for rods and other items to be inserted. All holes in steel pilings on the wet side of cofferdams shall be made watertight by welding steel plates over the holes after the piling installation is completed. Do not use explosives for cutting.

3.4 TOLERANCES

3.4.1 General

Completed sheet piles shall conform to the following tolerances:

TOLERANCES FOR METAL SHEET PILING

Tip Elevations: The final tip elevations for sheet piles shall be as shown or as modified by the Government as a result of the Contractor-performed exploratory pile driving program.

Horizontal Alignment: The horizontal tolerance at the top of the sheets shall be +6 inches at the point of cut off, unless noted otherwise.

Any pile out of horizontal tolerance shall be extracted and redriven at the Contractor's expense, at no additional cost to the Government.

Variation from Plumb: All piles shall be installed plumb within a

SECTION 31 41 16 Page 14

TOLERANCES FOR METAL SHEET PILING

tolerance of plus or minus 1/8 inch in 12-inches (1%), unless noted otherwise.

Any pile out of plumb shall be extracted and redriven at the Contractor's expense, at no additional cost to the Government.

Cutoff Elevations: The maximum permissible variation of the top of pile shall be within plus or minus 1 inch of theoretical sheet pile cutoff as shown on the contract drawings.

Any pile falling short of the required tolerance shall be extracted and redriven or corrected by alternate methods approved by the Contracting Officer.

3.4.2 Control of Alignment and Size

The Contractor shall maintain accurate positioning of all piles. The Contractor shall have on staff a qualified Professional Land Surveyor for performing all surveys to maintain vertical and horizontal alignments.

Each pile shall be checked for proper horizontal and vertical alignment as it is driven. A final check for horizontal and vertical alignment of the pile shall be made once it is seated or driven to the required refusal.

Any improperly aligned pile shall be corrected before the next pile is driven. The Contractor shall review all corrective measures with the Contracting Officer, before they are performed.

3.5 QUANTITIES

The estimated quantities of sheet piling listed in the unit price schedule of the contract as to be furnished by the Contractor are given for bidding purposes only. Sheet piling quantities for payment shall consist of the linear feet of piling acceptably installed and removed. Installed quantities shall consist of all piling including fabricated sections driven between the required top and bottom elevations of pilings plus any additions thereto resulting from changes in design or alignment as provided in paragraph DRIVING.

3.6 INSTALLATION RECORDS

Maintain a pile driving record for each sheet pile. Indicate on the installation record: installation dates and times, type and size of hammer, rate of operation, total driving time, dimensions of driving helmet and cap used, blows required per foot for each foot of penetration, final driving resistance in blows for final 6 inches, pile locations, vibratory refusal tip elevations, driven refusal tip elevations, ground elevations, cut-off elevations, and any reheading or cutting of piles. Record any unusual pile driving problems during driving. Submit complete records to the Contracting Officer.

3.7 SPECIAL REQUIREMENTS FOR MEMBERS TO BE FURNISHED BUT NOT ERECTED

As specified in Sections 35 49 23.23 25 UPPER GUARD WALL and 35 49 23.23 26 LOWER GUARD WALL, some of the piling for the Lower Guard Walls is to be furnished and delivered to the designated storage, but are not to be

SECTION 31 41 16 Page 15 installed. This piling shall be painted as specified in Section 09 97 02 PAINTING: HYDRAULIC STRUCTURES. Sheet piling shall be stored and handled in the manner recommended by the manufacturer to prevent permanent deflection, distortion or damage to the interlocks; as a minimum, support on level blocks or racks spaced not more than 10 feet apart and not more than 2 feet from the ends. Storage of sheet piling shall also facilitate required inspection activities and prevent damage to coatings and corrosion prior to installation. Piling shall be sorted and inventoried as specified in paragraph RETURN OF UNUSED GOVERNMENT-FURNISHED PILING.

3.8 CONTRACTOR QUALITY CONTROL

3.8.1 Contractor Quality Control

The Contractor shall establish and maintain a quality control system for all pile operations. The Contractor's QC system shall conform to the applicable provision of Section 01 45 01 USACE QUALITY CONTROL. The Contractor's QC staff shall perform all necessary inspections including those conducted for safety and conformance with this technical section, and shall report all findings and any problems to the Contracting Officer. All inspection and test result forms shall be designed by the Contractor and approved by the Contracting Officer.

3.8.2 Inspection of Driven Piling

Perform continuous inspection during pile driving. Inspect all piles for compliance with tolerance requirements. Bring any unusual problems which may occur to the attention of the Contracting Officer. The Contractor shall inspect the interlocked joints of driven pilings extending above ground. Pilings found to be out of interlock shall be removed and replaced at the Contractor's expense. The Contractor shall use divers to inspect underwater interlocked joints of cofferdam sheet piling. Government divers may also inspect the interlocked joints. The inspection of cofferdams shall be performed after driving is completed, prior to filling each cell and connecting arc, and within 48 hours after filling each cell and arc.

3.8.3 Pulling and Redriving

The Contractor shall pull, as directed, selected pilings after driving to determine the condition of the underground portions of pilings. Any piling so pulled and found to be damaged, to the extent that its usefulness in the structure is impaired, shall be removed and replaced at the Contractor's expense. Pilings pulled and found to be in satisfactory condition shall be redriven when directed. Government furnished pilings pulled and not redriven shall be stored as directed.

3.8.4 Inspection Reports

The Contractor's CQC staff shall conduct daily inspections of all operations during the period which piles are installed. The results of all inspections shall be recorded on the approved forms for the particular inspection and submitted as part of the Contractor's daily QC report as described in Section 01 45 01 USACE QUALITY CONTROL. The Contractor's CQC staff shall report any certain failures immediately as required. Such reports of failures and the action taken shall be confirmed in writing in the routine reports. Detailed driving records shall be kept for all pile driving. The original records shall be furnished to the Contracting Officer within 48 hours. Records shall be made available upon request by the contracting Officer.

SECTION 31 41 16 Page 16

3.9 RETURN OF UNUSED GOVERNMENT-FURNISHED PILING

Government-furnished sheet piling that is not used in the permanent construction shall remain the property of the Government and shall be returned to the storage area. Cutoffs shall not be returned, but shall be disposed of by the Contractor in accordance with Section 02 42 00 DISPOSAL

OF MATERIALS.

3.9.1 Sorting, Cleaning, Inventorying and Storing

Returned Government-furnished pilings and pilings which are furnished for the cutoff walls but not installed shall be sorted, cleaned, inventoried and stored by type into groups as:

a. Government-furnished piling.

b. Piling furnished by the Contractor.

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SECTION 31 41 16 Page 17