Continuous Flight Auger Piles

SPECIFICATION 814

CONTINUOUS FLIGHT AUGER PILES

Copyright MAIN ROADS Western Australia

REVISION REGISTER Clause Authorised Description of Revision Issue Date Number By 814.02 AS 3582 title updated SDSE 07/09/2017 AS 5100 and Specification 801 added ASTM C1611 removed 814.04 Years of experience changed to 10 years 814.08 Self-compacting concrete added Binder requirement removed Slump flow requirements added Concrete placing time requirement removed

814.20 Strength of concrete changed 814.21 Sequencing requirement added 814.24 Reinforcement cage inspection and hold point added 814.30 ‘Every truck’ changed to ‘each pile’ ‘ASTM C1611’ changed to ‘AS 1012.3.5’ 814.34 Testing requirement at 56 days removed Concrete strength requirement for PDA test changed Whole document Reformatted SCO 26/04/2017 814.02 AS 5100 deleted SDSE/A 06/05/2015 AS 1478, AS 3582, AS 3972 and ASTM C1611 added 814.03 A section added for definition 814.04 A section added for competency of piling contract 814.08 Percentage of admixtures and the allowable time from batching to placing are recommended 814.26 Adjustment to tolerances on piles Whole document Significant editing Whole document Issue 1.0 SDSE/A 17/01/2011 CONTENTS

Clause Page No SPECIFICATION 814

CONTINUOUS FLIGHT AUGER PILES GENERAL 814.01 SCOPE 1. The work under this specification consists of piles constructed in the ground by excavation with a continuous hollow flight auger (CFA) which is subsequently and progressively withdrawn whilst replacing the excavated spoil below the auger tip with concrete injected under pressure. 814.02 REFERENCES 1. Australian Standards, Main Roads Western Australia Standards and Main Roads Western Australia Test Methods are referred to in abbreviated form (e.g. AS 1012, MRS 67-08-43 or WA 123). For convenience, the full titles are given below:

Australian Standards AS 1012 Methods of Testing Concrete AS 1012.3.5 Methods of testing concrete - Determination of properties related to the consistency of concrete - Slump flow, T500 and J-ring test AS 1478 Chemical Admixtures for Concrete. Mortar and Grout AS 2159 Piling - Design and Installation AS 3582 Supplementary Cementitious Materials AS 3972 General Purpose and Blended Cements AS 5100 Bridge Design

MAIN ROADS Specifications Specification 801 EXCAVATION AND BACKFILL FOR STRUCTURES Specification 820 CONCRETE FOR STRUCTURES Specification 822 STEEL REINFORCEMENT 814.03 DEFINITIONS 1. Piling Contractor: Any party that has entered into a contract to undertake installation of CFA piles on a MRWA project. 2. Designer: The qualified professional Engineer who designs the CFA piles on a MRWA project. 814.04 COMPETENCY OF PILING CONTRACTOR 1. Prior to award of piling contract, the Piling Contractor shall submit to the Past projects Principal or delegated authority evidence of past projects in the construction of CFA piles (and/or secant pile wall construction if applicable). Reference to successful completion of projects with similar pile sizes in similar soil conditions using the proposed equipment and procedures should be included. 3. The Piling Contractor shall provide evidence that all CFA piling operators Operator on the project have adequate training and experience in producing good competency quality CFA piles in similar ground conditions to those anticipated at the site. 4. The Piling Contractor shall provide for the duration of the CFA piling Supervision operations, a full-time supervisor with a minimum of 10 years’ experience in the construction of CFA piles. 814.05 PILE INSTALLATION PLAN 1. At least 4 weeks prior to commencing installation of piles, the Piling HOLD POINT Contractor must supply to the Principal or delegated authority full details of the pile installation plan including methodology, material, equipment, testing methods and contingencies in accordance with Annexure 814A, and competency as per 814.04 for approval to commence. 814.06 NOT USED MATERIALS 814.07 GENERAL 1. Materials used in the construction of CFA piles must be in accordance with the design requirements shown on the drawings. 814.08 CONCRETE 1. CFA piles shall only be used at sites where an uninterrupted supply of Concrete concrete can be ensured for each pile. 5. Except as modified below, concrete used for piling shall be self- compacting in accordance with Specification 820 CONCRETE FOR STRUCTURES, which specifies minimum strength and other requirements for the concrete classes as nominated in the drawings to achieve the required durability. For CFA piles the provisions of this clause override any conflicting requirements of Specification 820. 6. The maximum aggregate size shall be 14 mm unless otherwise approved. 7. The slump flow shall be in accordance with Specification 820 CONCRETE FOR STRUCTURES. 8. Mix design shall conform to Specification 820 and this specification. Any variation shall be reviewed and approved by the Principal or delegated authority. 9. The Piling Contractor shall ensure that the proposed concrete mix design suits his proposed method of construction. 10. Mix design shall be submitted to the Principal or delegated authority in accordance with Annexure 814A (6) for approval. 814.09 REINFORCEMENT 1. Reinforcement must be in accordance with Specification 822 STEEL Reinforcement REINFORCEMENT. 814.10 – 814.19 NOT USED OPERATIONS 814.20 GENERAL 1. Piles must be constructed in accordance with the installation procedure for Installation continuous flight auger piles in AS 2159. 11. CFA piles shall only be installed vertically. 12. An adequate site surface must be provided as a safe working platform for piling equipment at a suitable level above pile cut-off levels. 13. Ensure that installation of piles is timed so that other construction activities will not occur within vicinity that could dislodge or damage the concrete of the CFA piles until the pile concrete strength reaching 25MPa. 814.21 SET OUT 1. All piles shall be set out in accordance with design requirements and Set Out appropriate procedures taken to protect adjacent services, structures and piles. 14. Check the horizontal position and verticality of the piling/drilling rig prior to the construction of each pile. 15. The piling Contractor shall sequence the works in such a way as to provide sufficient distance between piles to ensure that adjacent piles are not damaged during drilling and construction of subsequent piles. 16. Locate construction equipment at sufficient distance from the pile being drilled and from recently constructed piles to avoid any displacement of the concrete column caused by the surcharge load of the equipment. 17. Confirm set out of all piles before commencing installation. HOLD POINT 814.22 AUGERING 1. The piling rig must have adequate power and torque capacity to install a pile to the depth of the piles shown on the approved drawings with provision for contingencies. 18. Suitable cutting heads and augers shall be used to auger to the design diameter and depth shown on the drawings. The Piling Contractor shall regularly check that worn components are replaced. 19. Augering must be carried out at a rate that prevents drawing of the surrounding material laterally into the pile hole. 20. Automatic continuous measurements shall be made and recorded during the drilling operation including depth of the auger injection point, speed of revolution, penetration per revolution, torque delivered to the auger, and progressive total number of auger revolutions. All measurements must be referenced to (or plotted against) the depth of auger injection point. 21. If the measurements or records indicate that lateral subsidence of the ground inside the hole has occurred, the Piling Contractor shall immediately stop augering, fill the hole with concrete and then re-drill the pile shaft after the concrete has had its initial set. 22. If during the installation process the pile auger refuses at a level above the specified toe level, rotation of the auger must be stopped and the Piling Contractor must determine the need for remedial works, in consultation with the Principal or delegated authority. 814.23 CONCRETING AND WITHDRAWAL OF AUGER 1. The concreting must commence immediately upon reaching the agreed pile toe elevation. The auger shall be pre-charged with concrete under suitable pre-agreed pressure prior to lifting. 23. The Piling Contractor shall use construction techniques which minimise disturbance at the pile toe. The auger stem shall be locked against rotation at the commencement of withdrawal. If it is necessary to rotate the auger to ease extraction, the auger must be rotated slowly forward, never reversed. 24. Lifting of the auger prior to blowing the plug closing off the hollow auger shall be avoided. If and in any case it shall not exceed 75 mm and prior to starting withdrawal, the auger must be re-penetrated to the original pile tip elevation while maintaining pressure on the concrete. 25. Extraction of the auger must be smooth without jerks, whilst maintaining the required concrete pressure and oversupply at all times. The concrete oversupply must not be less than 5% in accordance with AS 2159. 26. Concreting must be continuous to achieve concrete that is monolithic from the top of the pile to the base of the design cross section, without segregation and free of entrapped debris. 27. Any ground water must be displaced during concreting operations. 28. During auger extraction, if the concrete pressure or oversupply drops to zero or less, note the depth at which this occurred, stop the extraction, re- auger to 500 mm below that depth and then recommence the extraction. 29. If auger extensions are used, check the level of the concrete in the extensions, which as a minimum must be able to balance the overburden pressure at the discharge point at the tip of the auger. After removing an extension and after reconnecting the auger stem to the drive head, pre- charge the auger and re-auger one metre down prior to continuing auger extraction. 30. Continue concrete pumping until the auger tip rises to the working platform level or 300 mm above the designed pile cut off level, whichever is higher. A form at the pile top extending above the working platform shall be applied where it is necessary to achieve the required concreting level. 31. On completion of concrete placing and prior to reinforcement cage installation, the top of the pile shall be cleared of debris and any contamination shall be removed. 32. As a minimum, continuous automatic measurements must be made and recorded during the withdrawal and concreting operation for extraction rate (m/minute), volume and oversupply of concrete, flow profile, concrete pressure, auger revolution (if any, but not preferred), and depth of the injection point. All measurements must be referenced to (or plotted against) the depth of auger injection point. 33. The equipment and the concrete pump efficiency shall be calibrated in advance for each concrete mix to be used to ensure the accuracy of the reported concrete volumes to within 5%. 814.24 PLACEMENT OF REINFORCEMENT CAGE 1. The reinforcement cage shall be free from oil, rust or debris and HOLD POINT straight. It shall not be placed until inspected and accepted by the Superintendent or delegated authority. 34. The reinforcement cage shall be ready to be inserted immediately after concreting. 35. Reinforcement must be carefully aligned as shown on the drawings to allow the satisfactory construction of the pile caps. 36. Minimum nominal cover to reinforcement shall be 100 mm but cover spacers provided on the bars shall be 25 mm less than the nominal cover to facilitate insertion of the cage. 37. Prior to placement, check the reinforcement cage to ensure that it is clean and straight. Cages may be worked into the concrete by hand, supplemented by the use of approved vibratory drive head where required. Driving or hammering using plant is not permitted. Keep cage vertical during installation. 38. Spacers and ties shall be sufficiently robust to withstand the forces and vibration needed to install the reinforcement cages. 39. If the reinforcement cage cannot be placed to the specified depth, the cage must be removed and the pile re-augered and re-concreted. Re-use of the cage is permitted only if it is recovered to meet all requirements as per items 1 to 5 and Clause 814.09 of this specification. 814.25 TOLERANCES ON PILES 1. Piles must comply with the following tolerances Tolerances a. Variation from specified position in plan unless otherwise specified: ± 75 mm b. Deviation of pier piles from pier centreline: ± 50 mm c. Variation in c/c spacing of top of adjacent piles in secant pile wall construction (if applicable): ± 15 mm d. Variation from vertical in a 3m template unless otherwise specified ± 30 mm e. Variation from vertical in a 3m template from plan of pier centreline ± 15 mm f. Variation from vertical in a 3m template within plan of secant pile wall construction ± 15 mm g. Variation in specified cut-off level: ± 10 mm h. Variation in pile diameter: (see below) 40. The pile diameter shall not be less than shown on the drawings. The pile diameter may generally be larger than shown on the drawings, providing that the minimum distance from the outside of any pile to the edge of a concrete pile cap/pier/abutment as shown on the drawings is satisfied after taking into account construction tolerances. 814.26 PILE INSTALLATION RECORDS 1. The Piling Contractor must maintain accurate records for each pile Annexure 814B constructed. These records must include data shown at Annexure 814B. 41. The records for each pile including plots as specified in Clause 814.22(4) and 814.23(11) must be provided to the Principal or delegated authority within 24 hours of the completion of the pile. 814.27 PILE CUT-OFF 1. The Piling Contractor must trim the tops of pile to elevations indicated on the design drawings prior to construction of the pile caps. All contaminated and weak concrete or laitance must be removed to expose sound concrete over the full cross sectional area of the pile during trimming. 42. Piles must not be trimmed earlier than 24 hours after casting the concrete. TESTING 814.29 GENERAL 1. Prior to pile cap construction commencing, the Piling Contractor HOLD POINT must submit written pile test results to the Principal or delegated authority for acceptance. 814.30 CONCRETE SAMPLING AND TESTING 1. Concrete samples must be obtained from each pile, and must be tested for consistency and temperature prior to discharging into the pump hopper. Consistency shall be measured by slump flow in accordance with AS 1012.3.5. Additional samples may be required at the discretion of the Principal or delegated authority at times corresponding to reinforcement cage installation. 43. 44. Density measurement shall be undertaken on the samples prior to strength testing. 814.31 PRE-PRODUCTION TESTING 1. Prior to commencement of production pilling, a test pile shall be HOLD POINT constructed and tested with integrity testing and static load or dynamic load testing at the discretion of the Designer. Piling records for the pre-production pile installed must be made available to the Principal or delegated authority for review prior to commencement of the installation of production piles. 45. The test pile shall be located and detailed as shown on the drawings and shall include all construction, reinforcing, concrete, monitoring and inspection requirements of production piles. 46. After installation and testing, the soil adjacent to the test pile shall be excavated to a depth of not less than 3 meters for visual assessment of the concrete integrity and cover shall be verified by cover meter. The designer or the Principal or delegated authority may require the depth of excavation and cover checking to increase to 6 meters. 47. Installation plan and design correlations of the pile resistance with the site specific soil parameters shall be reviewed by the Designer and the Principal or delegated authority based on the pre-production installation and testing. This may result in a change of design of piles. 48. The Piling Contractor must comply with any additional requirements that result from this review. 814.32 INTEGRITY TESTING 1. The Piling Contractor shall carry out integrity testing using the method Integrity approved by the Designer and the Principal or delegated authority on the Testing test pile and the samples of production piles as nominated on the drawings or by the Principal or delegated authority on site. 49. The designer shall determine the percentage of the pile shafts to be tested for integrity in accordance with AS 2159, but not less than 10% when design load is governed by pile geotechnical capacity, or 20% when design load is governed by pile structural capacity. 50. Integrity testing and reporting shall be carried out in accordance with AS 2159 Appendix D - Integrity Testing. 51. Integrity testing equipment and technique must be capable of checking cross-section irregularities in piles and identifying the location and characteristics of any significant anomalies such as voids or contaminants. 52. Piles giving anomalous results must be subject to alternative testing by the Piling Contractor and may be rejected if the testing results indicate a lack of structural integrity, disadvantageous change in physical dimensions, or inconsistency in material. Alternative testing is at the discretion of the Principal or delegated authority but may include static load testing in accordance with AS 2159 to ensure the pile serviceability and ultimate geotechnical strength. All alternative testing is at no cost to the Principal. 53. Additional integrity tests on all piles at a particular pier or abutment may be required by the Principal or delegated authority if any of the tested piles give anomalous results, and all additional tests are at no cost to the Principal. 814.33 STATIC LOAD TESTING 1. The option of static load testing and frequency of the testing shall be Static Load determined by the Designer based on the nature of the project. Testing 54. If static load testing is specified as a result of 814.31.1, 814.32.5 or 814.33.1, testing and reporting shall be carried out in accordance with AS 2159 including Appendix A – Static Load Test, unless otherwise specified. 814.34 PILE DYNAMIC LOAD TESTING 1. The Piling Contractor must carry out pile dynamic load testing and analysis PDA Testing on the test pile and the samples of production piles as nominated on the drawings or by the Principal or delegated authority on site. 55. The Designer shall determine the percentage of the production piles to be tested, but it shall not be less than 10% of all production piles and not less than 1 per pier or abutment. 56. Additional dynamic load testing must also be carried out on piles in the event that pile toe levels vary by more than 2 metres from the test pile or designed toe level. 57. Pile dynamic testing and reporting shall be carried out in accordance with AS 2159 including Appendix B – High Strain Dynamic Pile Testing. 58. The Piling Contractor shall design and construct pile head extension required to prevent damage to the pile. Pile dynamic testing shall be carried out after the pile concrete has gained sufficient strength to prevent damage under the required hammer impact, and not less than 25 MPa and no less than one week after casting of the pile unless otherwise specified on the drawings. 59. The Piling Contractor shall supply all the appropriate pile driving equipment including hammer, crane and pile driving rig, and all instrumentation, hardware and software to carry out the dynamic testing. 60. The Piling Contractor shall be responsible for the testing date analysis (and calibration with static load tests if applicable) and demonstrate the maximum mobilised shaft and end bearing resistance. 61. The Piling Contractor shall include details of all the equipment and instruments applied for the test including hammer mass and rated energy in his method statement as listed in Annexure 814A. 814.35 – 814.80 NOT USED AS BUILT AND HANDOVER REQUIREMENTS 814.81 – 814.90 NOT USED CONTRACT SPECIFIC REQUIREMENTS 814.91 – 814.99 NOT USED ANNEXURE 814A

COMPONENT OF PILE INSTALLATION PLAN

The pile installation plan must include, but not be limited to, the following items:

1. List and performance characteristics of proposed equipment, including drilling rigs, augers and other drilling tools, pumps for concrete, mixing equipment, automated monitoring equipment, including details of procedures for calibrating equipment as required;

2. Description of pile installation procedures;

3. A plan of the sequence of pile installation so as to ensure adequate concrete strength is obtained before commencing drilling for adjacent piles;

4. Target drilling and concreting parameters for pile installation, including auger rotation speed, penetration rates, torque, and concrete volume factors;

5. Detail of methods of reinforcement placement, including supporting for reinforcing cages at the top of the pile and methods for centering the cages within the concrete column ensuring the required minimum cover to reinforcement is met;

6. Mix designs for concrete to be used on the project, including ratio of each component, aggregate grading curves, slump loss vs. time curves (which shall indicate a slump flow not less than 400 mm at 3.5 hours after batching) and strength development vs. time curves for mixes;

7. Equipment and procedures for monitoring and recording auger rotation speed, drill resistances, torque and auger depths during installation;

8. Equipment and procedures for monitoring and recording concrete pressures and volumes placed during installation;

9. Contingency plans for equipment failures during drilling, concreting or reinforcement installation, or the interrupted construction process;

10. Proposed recording forms to be used during construction and testing;

11. Methodology to ensure pile and pile reinforcement location and battering tolerance are met;

12. Details of the proposed integrity test and load test methods, including a method statement of each test type, the hammer size proposed, the test criteria and details of the record sheets proposed for monitoring results; and

13. Contingency plans for remediation and for piles deeper than design drawings. ANNEXURE 814B

PILE INSTALLATION RECORD

The records required under Clause 814.27 for each pile constructed must show:

1. Pile location;

2. Ground surface elevation (reference grade for pile length);

3. Pile toe depth or elevation;

4. Elevation of pile head;

5. Pile length;

6. Auger diameter;

7. Details of the reinforcing steel (number, size and grade of longitudinal bars, size and spacing of transverse steel; outside diameter and length of cage);

8. Slump and volume of concrete placed;

9. Theoretical volume of drilled hole;

10. Depth to which reinforcing steel was placed;

11. Date/Time of beginning of drilling;

12. Date/Time of completion of drilling;

13. Date/Time concrete was mixed;

14. Date/Time concrete truck arrived at project site, and copies of all concrete batch tickets used for the pile construction;

15. Date/Time of beginning of concrete pumping;

16. Date/Time of completion of concrete pumping;

17. Date/Time of placement of steel;

18. Weather conditions, including air temperature, at time of concrete placement;

19. Identification of all concrete samples taken from the pile;

20. All other pertinent data relative to the pile installation; and

21. All readings made by the automated measuring and recording equipment as listed in 814.22(6) and 814.23(11) together with pump efficiency calibration. GUIDANCE NOTES

FOR REFERENCE ONLY – DELETE GUIDANCE NOTES FROM FINAL DOCUMENT

1. All edits to downloaded Specifications shall be made using Track Changes, to clearly show added/deleted text.

62. If all information relating to a clause is deleted, the clause number should be retained and the words “NOT USED” should be inserted.

63. The proposed documents with tracked changes shall be submitted to the Project Manager for review, prior to printing the final batch of documents. When this final printing is carried out, the tracked changes option is to be turned off.

64. Before printing accept all changes in the document, turn off Track Changes and refresh the Table of Contents.

65. The Custodian of this specification is the Structures Design and Standards Engineer.

814.31 Pre-production testing

1. Static testing shall be specified in situations where piles are used in a pier, are fully utilised for capacity or the design factors of safety are minimal, and there is no redundancy allowed in case of pile failure. CONTRACT SPECIFIC REQUIREMENTS

The following clauses are to be placed under the CONTRACT SPECIFIC REQUIREMENTS, as required. After inserting the clause, change the clause number and heading to style “H2 SP” so it appears in the Table of Contents.

XXX.XX SUB HEADING (H2 SP) 1. Insert text (Main Table SP) Keyword SP 66. Insert text (Main Table SP) XXX.XX SUB HEADING (H2 SP) 1. Insert text (Main Table SP) 67. Insert text (Main Table SP) AMENDMENT CHECKLIST

Specification 81 Title: CONTINUOUS FLIGHT AUGER PILES Revision No. 4 No:

Project Signature: Date: Manager:

Checked by: Signature: Date:

Contract No: Contract Description:

ITEM DESCRIPTION SIGN OFF Note: All changes/amendments must be shown in Tracked Changes mode until approved. 1. Project Manager has reviewed Specification and identified Additions and Amendments. 68. CONTRACT SPECIFIC REQUIREMENTS addressed? Contract specific materials, products, clauses added? (Refer Specification Guidance Notes for guidance). 69. Any unlisted materials/products proposed and approved by the Project Manager? If “Yes” provide details at 16. 70. Standard clauses amended? MUST SEEK approval from Manager Commercial. 71. Clause deletes shows as “NOT USED”. 72. Appropriate INSPECTION AND TESTING parameters included in Spec 201 (Text Methods, Minimum Testing Frequencies verified). 73. ANNEXURES completed (refer Specification Guidance Notes). 74. HANDOVER and AS BUILT requirements addressed. 75. Main Roads QS has approved changes to SMM. 76. Project Manager certifies completed Specification reflects intent of the design. 77. Completed Specification – independent verification arranged by Project Manager. 78. Project Manager’s review completed. 79. SPECIFICATION GUIDANCE NOTES deleted. 80. TABLE OF CONTENTS updated. 81. FOOTER updated with Document No., Contract No. and Contract Name. 82. Supporting information prepared and submitted to Project Manager. Further action necessary:

Signe (Project Manager) Date d: :