This method statement details the proposed works connected with the off loading, loading and installation of sheet pile retaining wall using a 25tn excavator and Movax vibratory pile drivers unit to construct a retaining wall at the project.
The purpose of this method statement is to identify potential hazards and to provide a safe and considered method of work.
Sheet piling works will be completed in accordance with the program of works.
Piling Foreman will be responsible for ensuring that the operations are completed in accordance with this method statement and applicable project specifications.
Operations Manager will be responsible for ensuring the Piling Foreman has the necessary support for works.
The Operations Manager will be responsible for ensuring the Method Statement and Risk assessments are in place and, together with the Piling Foreman that site conditions match those envisaged for the works.
Safety and task lighting will be required at the start and end of the shift during the winter months. Lighting units will be positioned to ensure the lights do not shine directly onto the lower bund.
Pre-requisites to starting on site
A site safety induction is to be provided by contractor which will include the site emergency procedures and personnel authorised to give instructions.
All piling personnel will be inducted into this Method Statement and Risk Assessment and will be briefed by the Operations Manager/Piling Supervisor and a copy given to the client project manager.
Clear and safe access and egress to and from the site for working personnel shall be provided, adequate demarcation from other operations also to be arranged (Site clearance etc.)
Suitable haul road & access to be provided to all areas for the works, including stable and well maintained piling platforms.
This will be detailed in the Traffic Management Plan.
Removal of obstructions.
Adequate Welfare facilities.
Setting out of the pile line and levels.
A signed Permit to Work for pile installation operations.
Other permits as necessary (eg Hot Works permit for cutting/ burning operations).
Clear delineation and notification of any live overhead or underground services.
Site Mobilization
a) Deliveries
The Piling Foreman will inspect the platform prior to the Movax setting up.
If satisfactory, he will get the certificate signed off by the client project manager prior to any operations commencing.
Offloading of the plant and ancillary equipment will be carried out within the site boundary.
The low loader will reverse to the works area, the low loader will then be tracked off by the rig operator and track onto the cycle path. A banksmen is to be present at all times and the speed of the excavator is to be limited to a walking speed.
Goalposts will be erected under the cables to establish a minimum height.
All deliveries will be made to the main site compound.
No plant/materials are to be stored on the lower berm.
All delivery vehicles will arrive with suitable edge protection.
b) Equipment
Operations Manager will make the necessary arrangements (i.e. movement orders where necessary) for the delivery of the piling equipment to site.
The proposed plant to be used on the project will be as follows:
50v Movax unit
Telehandler
Weld set
Trailer unit
c) Labor and Small Tools
The labor shall travel in a Transit Van carrying any necessary small tools and oxygen / propane / cutting / burning equipment. The transit van will be required access into the main site compound.
The Movax operator will travel separately in his own transport.
Methodology for Sheet Pile Installation
Delivery of sheet piles to works area:
Piles will be transported from the laydown area in the site compound to the works area, this method will utilize a trailer unit which will be transported by either the telescopic handler or dumper.
Where live road will need to be crossed traffic control management to be provided.
Sheet piles will be loaded onto a trailer unit by means of the telescopic hander in the compound storage area.
The trailer unit will then deliver the piles to the works area using the existing road.
Once the trailer unit reaches the works area the 25tn Movax will unload the trailer and lay the piles along the cycle path ready to install.
Works will be carried out in close proximity of live overheads, a safe working zone will be established and the excavator will be fitted with a slew restrictor.
Contractor shall mark the minimum safe working area on the footpath.
Pitching and driving sheet piles using Movax
The Piling Foreman will liaise with main contractor/client and agree the setting out locations of the piles and associated levels.
Piling Foreman will inspect the platform provided for the Movax unit, if satisfactory he will obtain endorsement of the certificate by client representative before commencing any operations.
Sheet piles will be transported to the piling area by the trailer unit and offloaded using the 25tn Excavator.
The sheets will be stacked in bundles of three to allow the Movax to manoeuvre them if required.
Up to 8 meter long, single sheet pile will be picked up by the Movax side grip.
Pile will be placed on the track to allow the driver to manoeuvre the hammer over the pile and grip the section on the side.
The pile will then be lifted and positioned onto the required line for the retaining wall.
Pile will then be driven using the side grips of the hammer as far as possible depending on prevalent underlying ground conditions.
The jaws of the hammer will then be released and the hammer moved up the pile and re-gripped onto the section and driven further.
This will continue until the pile is driven far enough to allow the hammer to be positioned on top of the pile.
Once the Movax is positioned on top of the pile and attached via the bottom jaw of the hammer the pile will be driven to it’s final level or refusal, whichever shall be the lesser.
Main contractor will provide a machine to remove any material to allow the piles to be driven to finished level.
Next pile will be handled in a similar manner and pitched into the clutch of the previous pile.
The pile will be driven in the same manner as the first.
Pile installation will be continued in the same manner until the end of the pile line or a change in direction.
Pile installation records will be kept on a daily basis together with daily record sheets and provided to client at the end of each day for verification.
If sheet pile refuses due to obstructions, the ‘what if’ table will be reviewed for a possible solution.
The Project Manager will be informed by contractor.
Pile Back driving Sequence
If the piles refuse during driving with the Movax, impact driving may be required to drive the piles to final level to meet the project requirements.
An impact hammer will be mobilized to site and attached to the excavator.
The hammer will commence driving under operation by the piling operative.
Driving will be monitored throughout the driving process.
Driving will stop upon the pile final level being reached or refusal of the pile under the driving process.
Controls & Monitoring
Main contractor/Consultant will be responsible for clearly marking the line and level of all pile wall sections and confirming the levels prior to the rig moving to the next pile.
Each pile will be checked for verticality as work proceeds by the Piling Foreman using a sprit level.
The Piling Foreman will ensure that the piles are installed in accordance with the pile schedule and in accordance with the relevant drawings.
Records will be kept of any piles which fail to achieve the required drive depth.
Labor Requirements
Operatives engaged in the site works will be a piling foreman, Movax operator, and a piling operative.
All operatives are trained and experienced in piling works.
Training records of the operatives involved in the works will be provided at the pre commencement induction.
To ensure compliance with this method statement a briefing will be held for all personnel involved.
No visitors will be allowed within the immediate working area unless they are deemed experienced in this work.
All operatives shall be qualified for their appropriate role and carry their cards with them.
Safety and COSHH Requirements
Appropriate Risk and COSHH assessments are provided along with this method statement.
Generic COSHH Assessments included for the installation are as follows :
• Diesel
• Hydraulic oil
• Oxygen
• Propane.
• Grease
Housekeeping
All vehicles and plant will be kept in a clean condition.
The working area will be kept clean and clear of trip hazards.
Any spillages will be reported to main contractor and cleared immediately.
All waste will be deposited into skips provided by main contractor for disposal.
All plant will carry a comprehensive spill kit.
Environmental Information / Waste and Pollution Control
Fuel: Client will refuel (gas oil) plant and equipment from approved storage facilities. Refueling will be completed at the designated areas.
Plant Maintenance: Any essential plant maintenance required while on site will be undertaken either at the working area or at a designated bunded area as directed by the client.
Contractor will provide a spill kit in the form of absorbent mats and granules to soak up any accidental spillage during refueling or plant maintenance work. These will be bagged up and disposed off properly.
Should there be any cause of pollution to the water courses the main contractor will be informed immediately.
Drip trays will be used under small plant items at all times.
Noise & Vibration Control
Piling contractor will provide details of anticipated noise and vibration levels anticipated for proposed plant and equipment on request.
Actual site levels may vary from those stated depending on actual ground conditions and the degree of exposure at the work location.
Noise and vibration monitoring will be carried out during the installation of the sheet piles.
Fuel & Oils
Fuel is to be provided by client in a mobile bunded bowser and held within approved storage facilities. Refueling will be carried out away from the water course if any nearby.
Personal Protective Equipment (PPE)
All personnel shall be issued with the following PPE which shall be worn at all times:
Hard Hats Safety Boots – lace up only.
High Visibility Trouser and Vest (function designated)
Light Eye Protection
Gloves
Ear Defenders
Additional PPE will be worn as required for activities such as burning and welding and as required by the risk assessments.
Lifting Equipment
All craneage, chains, slings, shackles and shoes will have valid certification for inspection at all times. Present color of all in test lifting equipment is Red.
Daily checks to be made on chain clamp / lock-nut pitching chain and component connectors together with the standard daily rig check carried out by the operator.
Lighting
Safety and Task lighting will be provided as necessary by contractor.
Site lighting to allow safe movement around the site if needed is also to be provided by contractor.
Lighting units will be positioned to ensure the lights do not shine directly onto the lower bund.
Emergency Procedures
Emergency Procedures will be briefed by contractor as part of the site induction, including the responsible person, contact numbers and hospital directions.
Designated First Aider for the project will be known to all site personnel.
Third Parties
Third party assets are the responsibility of main contractor as indicated on the Permit to Work.
The site works described above will be completed out in a secure working area provided by client.