The purpose of this civil work method statement is to define the procedure for piling construction works at a project in accordance with the requirements specified in the relevant specifications, procedures and drawings, considering safety and quality of the work activities.
The scope of work may include piling construction works at the existing ground level, dewatering and excavation for the pile cut off level.
Before starting the piling work at the site ensure the availability of below list of equipment and tools.
- Drilling Rigs
- Concrete Pump
- Concrete Pressure Hose
- Vibro Hammer
- JCB
- Dump Trucks used for disposal of debris
- Plate Compactor
- Pumps
- Bobcat
- Telehandler
- Manual Shovel
Roles & Responsibilities
Project Manager
Ensures that the project works in his zone are carried out in accordance with company policies and in accordance with the requirements of the project quality plan.
Ensuring the full compliance of subcontractor operations with corporate quality policies and with the requirements of quality plan.
Make sure that all the equipment requirement to execute the works according to the construction program are available, in good condition, and provide any additional equipment.
Coordinate with the Construction Manager, Project Engineer, Safety Engineer, Foreman and Surveyor for a safe and proper execution of the works.
To guide specific attention to all safety measures in co-ordination with the safety officer/engineer.
Construction Manager
Ensure area is ready and safe to start the works.
Set up necessary equipment and plant through discussion with the Project Manager and Project Engineer/Works Supervisor.
Ensure the works are carried out according to the specification, quality and approved shop drawings.
Liaise and coordinate with the project manager for the agreed sequence of works with respect to the construction methodology and program.
Allocation of required manpower through co-ordination with the PM.
Ensure the availability of the risk assessments for the works activities in hand.
Provide sufficient and safe access for operatives, trucks and pumps.
Take precautionary measures with regards to protecting works from hot weather, wind, rain and sun etc. as applicable.
Project Engineer
The engineer will carry out his duties in a manner that will be coordinated by the project manager on a daily basis, and will ensure proper distribution of the workforce and equipment at different site locations.
To be aware of test frequencies related to the formation level.
Control disposal of waste excavation material according to the instructions from the project manager/director.
Coordinate with the Safety Officer to maintain safe working and proper housekeeping of the site. To comply with the safety measures and ensure that all the HSE team is aware of the same to prevent accident and loss.
To monitor and check all activities and ensure that works will be carried out according to specifications, quality and approved drawings.
To inform the QC Inspector of the areas ready for inspection.
QA/QC Engineer / Inspector
Ensuring that Consultant/Client inspection requests are implemented.
Compilation of all necessary quality control checklists.
Assisting consultants during the Inspections.
Coordinating with the third party lab regarding tests and results.
The control of work performance by means of checking the work before consultants’ inspection and issuing RFIs & punch lists as necessary.
Completion of documentation to verify the work performed.
Controlling all inspection activities on site in line with ITP’s.
Ensuring that all test equipment including surveying equipment is calibrated and is suitable for use on the project site.
Surveyor
To establish benchmarks from agreed reference points, provide required setting out and level markings and follow up with regular checks.
Co-ordinate with the Project Engineer / Foreman and ensure the approved shop drawings/construction drawings will be implemented properly.
Maintain survey details and reports, periodically check the progressing works and advise the project manager of any deviation from the drawings.
HSE Engineer/Officer
To ensure implementation of all safety measures related to the nature of works being carried out, and in accordance with the Project Safety Plan.
Ensure that all the persons involved in the works are aware of their responsibilities, and that they have enough understanding of the safety procedures.
The safety officer in co-ordination with the Project Manager will ensure that all the implemented safety measures are effective enough to maintain safe working conditions on the site.
To maintain continuous inspections of the site activities, advise and train persons on a daily basis to prevent accidents and personnel injury.
Give special concern to housekeeping, and ensure that the site is well maintained clean and tidy.
To ensure all the relevant safety sign boards for different works are in place.
Foremen/ Works Supervisor
Ensure the work progress inline with the targets and sequence as per the PM directions and orders.
Liaise with the Project / Construction Manager for the allocation of the work force, ensuring adequate manpower is available.
Liaise with the site manager to ensure all the plant/materials are available to perform the construction works.
Full time supervision to ensure the works are in accordance to specifications, quality and IFC drawings.
Piling Works from the existing Ground Level – Casting and Boring of Piles
Prior to piling works, the site platform should be prepare and maintained in a dry and safe condition.
The platform level should be installed at the existing ground level. The Surveyor checks and verifies the platform level, cut-off level, concrete and steel cage levels.
The Surveyor shall carry out the setting out of the pile centre positions as per approved shop drawings. The setting out of pile locations should be approved by the Consultant. The setting out pegs will consist of steel reinforcing bar that will be driven slightly below the surface of the platform so they will not be disturbed by the piling activities. The pegs will be marked with a color ribbon so that they can be easily located.
Drilling shall be carried out with the use of C.F.A rig. Continuous Flight Auger piles are installed by drilling rig with rotary Continuous Flight Auger. The drilling rig auger shall be set over the pile point location and soil will be drilled to the predetermined pile base elevation using continuous flight auger with hollow stem. During drilling process as soon as the auger touches the rock level the pressure gauge in the cabin operator will show the starting of the hard layer. From the level we will make two times the diameter of the pile as socket length. We will make sure to have the same toe level for all piles in one building.
The ready mix concrete will be supplied by the approved Ready Mix Concrete supplier as per approved mix design for C.F.A. piles. The concrete of suitable workability to ensure satisfactory emplacement within the bore hole is then pumped under pressure through the hollow centre of the auger to the bottom of piles.
Placing of reinforcement cage
As soon as the bore hole is filled with concrete, the concreting of pile is complete and the steel cage will be placed in the filled hole, the readymade rebar cage shall be lifted by the service winch of the drilling rig and then lowered into the bore hole by Vibro hammer until the required depth and maintaining sufficient cover by PVC spacers as approved. The length of cages shall be in accordance to the approved pile design.
Pile Numbering: All piles will be numbered for each location for easy reference and the as built drawings to be submitted.
This procedure is based on the approved method statement for C.F.A piling prepared by piling subcontractor and approved by the consultant.
Installation of Shoring
The Contractor Surveyor shall mark and establish the location of shoring for each structure.
Contractor shall install the shoring as per the Surveyor setting out for the location of each shoring.
Shoring will be installed in the three sides of the building and the one side is open for the access of equipment’s.
The contractor ensures that all shoring have capability to prevent the soil to fall down or collapse.
Excavation for Pile Cap Location
Using JCB, excavate the pile cap as per level and guidelines shown in the approved for construction drawings and approved shop drawings. The contractor workers shall trim all permanent excavation to the convenience slopes and shall leave the surfaces smooth and even.
The contractor is also responsible for ensuring that adequate safety measures are taken to protect the existing concrete structures, such as concrete pile and Site Personnel from any excavation hazards. If the excavation works are carried out beyond true lines and level other than shown in the approved shop drawings, the Contractor shall fill with approved materials to the required line and level.
The Contractor to submit the inspection request to the consultant after all necessary excavation works/earthworks for pile cap is complete and ready to receive permanent materials like concrete works/termite control etc.
For termite control, please refer to approved method statement for termite control
For Concrete Works please refer to method statement for Cast in place concrete for pile cap.
For waterproofing and protection board please refer to approved method statement for waterproofing works.
Backfilling works and compaction for pile cap location
Backfilling works for pile cap shall consist of suitable materials.
Prior to backfilling works for pile cap, the contractor ensure that the areas to be backfill are clean, the waterproofing and protection board are 100% complete and ready to receive the filling materials.
Remove the unsuitable materials prior to start backfilling works.
Using Bobcat or JCB and Telehandler, the Contractor start backfilling works using suitable materials as stated in specifications and place in one layer until completed to the top level of pile cap.
The backfilling material to be compacted by hand tempers near the perimeter of pile cap and manual compaction to prevent damage to waterproofing on the pile cap.
Spray water during compaction.
The Contractor can use plate compactor for the compaction of big areas and without concrete and waterproofing obstruction.
When backfilling and compaction against foundation/walls, special care shall be taken to prevent damage to waterproofing on walls.
The Contractor Surveyor should be checked the require backfill/compaction level as shown in the approved shop drawings.
The Contractor to submit the inspection request to the consultant after all necessary compaction was completed on the pile cap level and ready to receive the backfill materials for tie beams.
Earthworks for Tie Beams and Footings
Site Works Preparation prior to excavate the Tie Beams and Footings
The Contractor shall conduct a site survey prior to start any excavation works.
The Contractor ensure that all excavation works shall carried out in accordance to the lines and grades / levels shown in the issued for construction drawings and approved shop drawings.
Using JCB, Bobcat and Dump Trucks, contractor shall remove all unsuitable materials found above and below the tie beam and footings level and immediately replace with suitable materials/approved backfill materials.
The Contractor Surveyor provides setting out, axis and level for the location of tie beams / footings.
Excavation for tie beams and footings location
Excavate the tie beams / footings as per level and grade shown in approved shop drawings and using JCB.
The Contractor workers shall trim the all permanent excavation to the convenience slopes and shall leave the surfaces smooth and even.
The Contractor also responsible for ensuring that adequate safety measures are taken to protect the Site Personnel from any excavation hazards.
If the excavation works are carried out beyond true lines and level other than shown in the approved shop drawings, the contractor shall fill with approved materials to the required line and level.
Backfilling for tie beams and footings location
Backfilling works for tie beams and footings shall consist of suitable materials as stated in specification.
Prior to backfilling works for tie beams and footings, the contractor ensure that the areas to be backfill are clean, the waterproofing and protection board are 100% complete and ready to receive the filling materials.
Remove the unsuitable materials prior to start backfilling works.
Backfilling Works without MEP Pipes:
Using Bobcat or JCB and Telehandler, the contractor start backfilling works using suitable materials as stated in specification and placed in one layer until reached to the bottom level of blinding for ground floor slab.
The backfilling material is compacted by hand tempers near the perimeter of tie beams and footings and manual compaction to prevent damage to waterproofing works.
Spray water during compaction.
The Contractor can use plate compactor for the compaction of big areas and without concrete and waterproofing obstruction.
When backfilling is against foundation/walls, take special care to prevent damage to waterproofing on walls.
Backfilling Works with MEP Pipes:
Using JCB/Bobcat and Telehandler, the contractor starts backfilling works using suitable materials as stated in specification and placed in one layer until achieved the invert level for the location of pipes.
The backfilling materials are compacted using plate compactor and spray water during compaction.
Then the contractor starts installation of pipes for MEP works.
Contractor shall submit the inspection request to the Consultant after all necessary piping works is complete including concrete formworks for the protection of pipes.
Concrete protection of pipes to be provided according to contractor BOQ.
The strength of concrete to be used in pipe protection is 20 N/mm² same in blinding concrete.
After the installation of pipes, the opening between the pipe sleeves and pipes should be closed using approved materials.
After the approval of MEP works, the contractor starts backfilling of pipes using JCB/Bobcat and Telehandler and places the backfilling materials in one layer until achieves the bottom level of blinding for ground floor slab. When backfilling against MEP pipes, special care shall be taken to prevent damage to pipes.
The contractor Surveyor shall check and ensure the backfill/compaction level as shown in the approved shop drawings.
Earthworks for Ground Floor Slab
Site Works preparation and Removal of Unsuitable Materials:
The Contractor Surveyor provides setting out, axis and level for the location of blinding for ground floor slab.
Contractor will remove the unsuitable materials found on the backfilling works and immediately replace with suitable materials.
The contractor ensures that all MEP pipes are complete and approved by the consultant.
Backfilling and Compaction works under the blinding of ground floor slab
Prior to start the backfilling activities for all substructures, the lab technician shall submit the test result for backfilling materials.
The backfilling works for ground floor slab shall consist of suitable materials as stated in specification.
Using Bobcat or JCB, the contractor starts backfilling works using suitable materials and places in one layer until reaches to the final level.
The backfilling material is compacted using plate compactor and spray water during compaction to attain the require value of compaction test.
When backfilling against MEP pipes, special care shall be taken to prevent damage to the pipes.
Compaction Test for the final layer and level
The contractor to submit the IR to Consultant prior to start the compaction test and after all necessary earthworks for ground floor slab are complete and ready to receive the permanent works such as termite control and blinding.
The Lab Technician shall be responsible to conduct the compaction test.
Compaction test IN-Situ Dry Density BS 1377 Test 15 will be conducted in two points per building in the final layer and compaction level.
Contractor surveyor shall check the required backfill/compaction level as shown in the approved shop drawings.
The Contractor will start the application of termite control after the approval of compaction test by the consultant.