STANDARD WORK PROCEDURE FOR CFA - Amplus …

1 Amplus Ltd Foundation and Geotechnical Specialists Amplus LTD QUALITY SYSTEM Contract No: Page: 1 of 4 Issue Date: Approved By: GNH STANDARD work PROCEDURE FOR CFA PILING PRELIMINARIES Works Supervisor shall confirm that the access, piling platform, attendances, details of underground services and protection, as provided by the Main Contractor, are satisfied. If not he shall inform the Main Contractor (using CVI/RFI form) and obtain instructions in writing. Agree sequence of work with Main Contractor. H Works Supervisor For contracts where Amplus Ltd are responsible for the design, the piling will not commence until a pile schedule has been prepared. This is to be approved and signed by the Design Engineer. In addition the pile design and schedule shall be submitted to the client and approval requested.

2 H Design Engineer 1. CFA RIG AND AUGER CONSTRUCTION The rig mast shall be raised to its full extent, secured to the base frame and made ready for piling mode. Rig Operator A suitable position, free of underground services and obstructions will be located in order to construct the auger string. Permit to dig must be signed by main contractor prior to any drilling. Piling Foreman & Main Contractor The lead auger shall be attached to the rig rotary head and drilled into the ground at the agreed position. Rig Operator & Frontman Additional lengths added using the same as section until auger string is fully constructed. Rig Operator & Frontman 2. PILE LOCATION The position of each pile shall be marked by a steel pin driven vertically into firm ground and referenced with a number.

3 Main Contractor With the mast in a vertical position and the gates closed, the auger tip shall be lowered and manoeuvred to be directly and precisely over the setting out pin. The mast shall then be lowered. Frontman 3. PILE DRILLING Before drilling commences the mast shall be checked for verticality in both orientations by reference to the integral bubble gauge or spirit level. H Frontman With the auger tip at ground level the depth gauge is to be zeroed. The pile number shall be entered into the data logging system if required under the contract. H Rig Operator A Controlled Zone must be identified with barriers, erected to protect persons from the working areas Frontman Amplus Ltd Foundation and Geotechnical Specialists Amplus LTD QUALITY SYSTEM STANDARD work PROCEDURE FOR CFA PILING Contract No: Page: 2 of 4 Issue Date: Approved By: GNH The auger shall be drilled down to the required depth or refusal.

4 When firm ground is reached the gates may be opened. Frontman Whilst drilling, ground conditions must be regularly inspected and checked with the site investigation report if possible. Any concerns in pile construction or ground quality must be reported to the Amplus Limited office, Tel 01534 863545 H Rig Operator & Frontman After reaching the prescribed depth or refusal, the auger shall be held and the depth checked. H Rig Operator 4. PILE CONCRETING The concrete pump and hose shall be primed with cement grout at the commencement of each days piling work . Pumpman The pump man shall check the concrete delivery docket. R Pumpman If required, plasticizer will be added before accepting discharge of the concrete. The pump operative will then visually inspect and confirm the satisfactory condition of the concrete prior to pumping.

5 H Pumpman Ready mix concrete shall be discharged into the pump hopper. When signalled by the driver pumping shall commence. Driver & Pumpman The auger is withdrawn only when pumping has commenced. Rig Operator As the auger is withdrawn, concrete shall be pumped through the auger stem to construct the pile. This stage of the operation shall be controlled directly by the rig operator using signals to the pump man. The rig operator shall monitor concrete flow, pressure, depth and rate of extraction during the concreting process. Rig Operator & Pumpman Rig Operator During the concreting operation, the concrete within the auger stem shall be kept at a positive pressure. Rig Operator As the auger is being withdrawn, the flights above shoulder height shall be cleaned of spoil, either by spade or auger cleaner.

6 At regular intervals during withdrawal, spoil built up at the foot of the auger shall be withdrawn clear by machine to allow auger cleaning to continue. Frontman & Machine Driver When the auger tip is withdrawn from the ground the rig shall be tracked away. The spoil at the pile head shall be drawn to one side by machine to expose the pile top. Frontman & Machine Driver When all concreting is complete at the end of shift, the pump shall be washed out with a high pressured jetwash and the concrete lines are blown through with compressed air. Pumpman & Frontan 5. REINFORCEMENT INSTALLATION The reinforcement cage shall be fabricated, in line with the design specification. Steelfixer Amplus Ltd Foundation and Geotechnical Specialists Amplus LTD QUALITY SYSTEM STANDARD work PROCEDURE FOR CFA PILING Contract No: Page: 3 of 4 Issue Date: Approved By: GNH The cage shall be checked to ensure correct fabrication H Piling Foreman Any spoil shall be shovelled from the pile head and position of the pile determined.

7 The pile cage shall be lowered vertically into the fluid concrete. Longer or lightweight cages may be "surged in" or pushed/tapped in using the excavator bucket. The cage will be centralised within the pile. If applicable, bar end protection caps will be fitted if reinforcing bar is protruding. Frontman & Machine Driver 6. AFTER PILE CONSTRUCTION The main Contractor shall check the position of each pile shortly after construction and advise Amplus Ltd if the pile is outside tolerance: 75mm in plan position. Main Contractor Care shall be taken to ensure the pile is not tracked over or the nearby ground surcharged until the concrete has achieved sufficient strength to withstand such additional stress. All site personnel The Main Contractor shall ensure that traffic is kept off piling area.

8 Main Contractor Pile logs shall be completed daily and submitted for signature. Rig Operator 7. DE-RIGGING OF PILING RIG AND DISMANTLE OF AUGER STRING A suitable position, free of underground services and obstructions will be located in order to de-rig the piling rig and dismantle the auger string. Piling Foreman/ Main Contractor The tip of the auger shall be lowered directly over the agreed position and drilled down to the required depth for auger dismantle. Rig Operator The auger string is dismantled in stages until the drill head is free of the auger string. Rig Operator & Frontman The mast lowered and secured into transport mode. Rig Operator & Frontman 8. RECORDS The following records will be completed at the appropriate time and submitted for approval where necessary.

9 CFA Pile Construction Log & Daily Diary Confirmation of verbal instructions/request for further information/site letter Rig Operator Works Supervisor Amplus Ltd Foundation and Geotechnical Specialists Amplus LTD QUALITY SYSTEM STANDARD work PROCEDURE FOR CFA PILING Contract No: Page: 4 of 4 Issue Date: Approved By: GNH SAFETY All personnel on site operating as a crew with the CFA machines are trained in the safety aspects of the piling procedures with these types of machines, in particularly to stand clear of the front of the machine whilst in operation. INDEX R REVIEW POINT is a stage where documents are reviewed, checking that all materials certificates are in order. H HOLD POINT is defined as a specific stage in the construction process beyond which the works will not proceed without an inspection or check being made and recorded by Amplus Ltd personnel.

10 W WITNESS POINT is defined as a Hold Point for Amplus Ltd personnel but where the Client's (or other) representative has requested to witness the inspection. Should the Client's (or other ) representative not be present, the work may proceed. N NOTIFICATION POINT is defined as a specific stage where the Client's (or other) representative is given notice that an activity will take place.