METHOD STATEMENT FOR PILE CAP CONCRETING
1.0 INTRODUCTION
This Method statement describes the way of doing concrete casting for Pile caps. Quality Assurance and Quality controlling plan also enclosed in the method statement.
2.0 REFERENCES
· Structural Construction Drawings
· Inspection sheet for structural work
· Mixed design reports
3.0 RESOURCES
3.1. Material
1. Cement Blocks (100 mm thk. Solid )
2. Ordinary Portland Cement
3. Aggregate
4. Sand
5. Water
6. Admixtures
7. Ready mix Concrete
8. Reinforcement
The mix proportions are designed by mix design and verified by Trial mix and trial workability tests
3.2. Machinery and Equipment
1. Batching plants
2. Truck Mixers
3. Concrete Distributor
4. Shovel
5. Porker/Shutter Vibrator
6. Concrete Chute
7. Mason Trowel
8. Level Bar
9. Level Machine with staff
10. Wooden Float
11. Plumb bob
12. Water pressure gun m/c 15.wire brush
3.3 Man Power
1. Site Engineer
2. Assistant Engineer
3. Technical officers
4. Survey helper
5. Mason
6. Skilled workers
7. Unskilled workers
8. Standby carpenter
9. Standby MEP service workers
10. Machine operators
4.0 Formwork
This is a major activity, which bear the weight of concrete until it gets the required strength. Therefore, it is essential to take care of the correct methodology for fixing and supporting.
4.1 Type of formwork
· Sides of Pile caps
4.2 Preparation of formwork
· After laying screed concrete, setting out work will be stared for pile cap 100 mm thick solid cement blocks used as a form work for pile caps.
· Verticality of block walls will be checked using plumbs
5.0 Re bar Work
· Mill reports and test reports for steel will be submitted to the consultant before execution of work.
· Re bar schedules will be prepared by an Engineer and checked by QA/QC Engineer before sending to consultant’s approval.
· Cutting and bending will be done at site or bar bending yard (Sanken head office) accordingly bar schedule approved by consultant.
· All laps, joints and anchorage will be kept to the standard given in drawing by design Engineer.
5.1 Equipment
· Bar bending machine
· Bar cutting machine
· Chop saw m/c
5.2 Reinforcement placing
· All steel bars will be cleaned before placing
· Cover blocks will be used to maintain the adequate cover to reinforcement
· Chairs or Stools will be used to maintain the gap between top and bottom bars
5.3 Cover to reinforcement
Cover to reinforcement main bar will be as follows.
· Pile cap top 75 mm
· Pile cap bottom 150 mm
· Pile caps sides 75 mm
Minimum lap length as specified by design Engineer
5.5 Check List of Re bar
· Steel sizes, spacing and position
· Steel tying and binding
· Lap length, anchorage length
· Covering
· Chairs or stools between top and bottom net
· Cleanliness
6.0 CONCRETE WORK
6.1 Materials
· All concrete grades will be used as specified in drawings.
6.2 Concrete Used
· Using concrete mixtures done by manually using drum mixture at site for G15
· Batching Plant Mixed (Concrete batching plants Mix Designs approval gets from consultant)
6.3 Transportation of concrete
· Concrete will be transported to the site by truck mixers from batching plant
· Site mixed concrete done by at site using drum mixture for G15
6.4 Placement of Concrete for pile cap
· Consultant will be informed at least 12 hours before approval required
· After the approval of consultant for reinforcement and form work, concreting will
be done with all necessary equipment
· Dust and debris, which exist inside the formwork, shall be blown and cleaned well, prior to commence the concreting. Cavities if there are any, shall be sealed to avoid grout leakages.
· Concrete shall be poured in to the pile cap by manually with using wheel barrows.
· Proper compaction shall be done by using poker vibrators. Level of the pile cap and the surface finish shall be maintained while doing the concreting.
· Chute will be used where required keeping slopes not to cause segregation
· Poker vibrators shall be used to compact the concrete well
6.5 Leveling of Concrete
· Height gauges will be used to maintain the correct level
· Concrete finish level will be marked at column reinforcement to control the pouring on pile caps
· Concrete finish levels will be checked after concreting using leveling instrument.
6.6 Compaction of concrete
· After pouring one layer, the compaction of about 3 secto 5sec shall be done inserting vibrator based on the marks. The vibrator needle should not disturb previously concreted layer.
6.7 Testing related to the concrete work
· Slump will be checked for each truck mixer and record with consultant/client representative
· 150mmx150mmx150mm test cubes will be produced for compressive strength checks for 7 days and 28 days
· Test cubes will be checked in approved labs
6.8 Curing of concrete
· Curing shall be started as soon as possible and practical after placement of concrete
· The concrete shall be coved with a sand and kept constantly wet for a period of 7 days
7.0 Quality Assurance/ Inspection and testing
7.1 Material
Slump Value: Specified slump value +/-25mm
Grade of concrete: Grade C30
7.2 Concrete Sampling and testing plan
Samples shall be taken for cube crushing test as follow by specification.
7.3 Inspection for construction
All kinds of inspection for construction shall be carried out by the QA/QC Engineer of Sanken along with consultant representative as per the standard and specification.
However, prior information shall be given to consultant representative at site to proceed necessary checking periodically and make final comment.
Inspection shall be carried out while progressive of work and approval shall be granted without affecting to the progress of work.
Following are used for the quality assurance and control work.
01. Request for inspection
02. Approval sheet for structural works
03. MEP inspection sheets if available
8.0 SAFETY PLAN
· All the dangerous areas must be barricaded
· Safe flat forms for working at higher levels shall be provided.
· Safety Guard rails shall be provided at the perimeter run.
· All the electrical wires and sockets such a way that must be covered to safety regulation
· Very good site illumination will be provided, if concrete pouring continues at night
· Water pumps must be ready at any time for immediate use.
· First aid facilities and vehicles for emergency cases shall be available at site
