After backfilling works the next is casting or pouring concrete on slab on grade (ground), make sure that all the area beneath grade slab have been properly backfilled and compacted.
Approval must be obtained from the Engineer for waterproofing and backfilling works prior to start slab on grade casting.
Here is the method statement for pouring concrete on Slab on Grade preparation and concrete pouring.
1. Title
Method Statement for Casting or pouring concrete on Slab on Grade.
2. Purpose and scope
The purpose of this method statement for casting or pouring concrete on slab on grade is to explain the proper procedure on how to prepare and cast slab on grade or any horizontal element or member including fixation of steel reinforcement, MEP embedment’s, fixing of shutter etc. without injuries.
3. Work procedure
3.1 Site planning
• Delivery – fresh concrete shall be batched from the approved supplier of concrete. Concrete will be delivered direct to the site and to be received by assistant Quality Engineer for checking of the required criteria of concrete. The assistant QC Engineer will make sure the concrete delivered is as per the approved design mix for the situated member to be casted.
• All data for testing on fresh concrete at site shall be recorded on the concrete pour card.
3.2 Preparation for pouring concrete on slab on grade
• After the blinding is casted and placement of waterproofing is done, the preparation and casting for slab on grade shall be done.
• Fix the reinforcement steel as per the approved drawings, sometimes A393 BRC mesh is indicated in the drawing and most commonly use in 250mm thick concrete grade slab.
• Any loose binder or ties along the splices reinforcement steel shall be re-tightened. Bend inward the free ends of the binding wire or ties.
• Use PVC spacer for vertical bars and concrete spacer for bottom as concrete covers.
• Ensure and coordinate with MEP staff for any MEP works required on the area as per approved drawings.
• Fix the forms such; supports, sleeves etc., if any.
• Any damaged materials used for form work or shutter like plywood shall not be used.
• All surface of forms or shutter facing concrete shall be treated with shuttering oil and dampen with water few minutes before concrete will be poured.
• Clean the slabs on grade using air compressor for dust or any small particles or deleterious materials that may impair the workability of concrete.
• The surveyor will then checked the level of the projected top surface of the slab and place level strips if necessary to mark the exact level.
• The concreting are as must be arranged with necessary equipment or tools for concreting use such as vibrators, power float machine, shovel etc.
• Skilled and unskilled labor shall need to use safety requirements such as safety helmet, safety shoes, goggles, gloves, vest etc.
• Safety devices and safety warnings shall be provided starting from the site entrance gate till the casting area.
• Proper lighting must be available in case of night concreting.
3.3 Concrete pouring on slab on grade
• The concrete mixer must be stopped at the check point for the inspection of slump test and to obtain sample cubes for test.
• One set of cubes shall be taken every 50 cubic meter concrete, each set consisting of 6 cubes, 3 cubes to be tested on 7th days and 3 cubes to be tested for 28th days.
• Extra three cubes can be made for re-checking if in case circumstances may happen.
• Unload the concrete within 90 minutes from the batching plant loading time.
• Compact the concrete properly by using mechanical vibrators, extra vibrator shall be available in case of any shortage or mechanical problems.
• Use approved hardener material after casting concrete when required. Make sure applications shall be as per manufacturer’s recommendation.
• Use the power float for the smooth finish surface purpose. Store extra power float near the casting area in case of any mechanical malfunctioning.
• Cure the casted area properly with covering concrete with hessian cloth and polythene sheet on top but before placing the concrete wet the hessian with water.
• Cure the concrete by spraying water three times per day for a period of 7 days.
• The casted area or member shall be protected by placing barricades to prevent plants and machineries damaged the concrete.
• Concrete pour card shall be filled by Quality Engineer and to be submitted to the Engineer including concrete delivery notes, this task will be done whenever required.
• Concrete cube test report shall be submitted to the Engineer
4. Safety
- All works shall comply with safety procedure or instruction set out in project safety plan and municipality rules and regulations.
- Basic PPE to be worn by all staff and laborers.
- Trained operator and banksman would be engaged to control or operate heavy equipment machine.
- Provide sufficient lighting whenever night casting.
5. Equipment and tools
- Concrete Pump
- Concrete Mixer
- Mini truck
- Bob cat
- Concrete vibrators
- Wheel borrow
- Slump tray
- Slump cone and other associated tools
- Rubber hammer
Related Article:
- Method Statement for Footing Concrete Pouring
- Method Statement for Blinding Works
- Why Understanding About Method Statement Is Important To Engineers In Construction
6. Materials and References
- C40/20 Concrete Grade with additives
- Deformed bars or A393 BRC mesh
- Approved drawing
Thank you am grateful for your site
Thanks for stopping by.
Thank you for this site.
Any method statement for fixing a concrete reservoir which is leaking due to honeycombing and segregation on some sections?
Please, do you have any concrete method statement of the sloped foundation?
Considering a big volume and distance, can we pour concrete one time and one place/form from two different batching plants?
There is nothing wrong as long as the concrete has the same strength and make sure that your engineer agrees on that.
I can gain the knowledge from your site which is really interesting. Thank you for this article because it is really informative about cement mortar mix it is really informative and gives best suggestion about it. Thanks a lot and have a great day.
As seen around, most of the exterior plastered walls seems to be wavy/undulation when completed with painting works during some part of the day sunlight. Would you please tell us what will be the acceptance criteria for this painting works/plastered walls?
My work is rejected due to the above problem.
You can find out here on one of my blog posts the “Tolerances” just type in “tolerance” on the search tab and the website will reveal it for you. I’ve taken that from our specification. The plaster should be properly checked and should be within tolerance before the application of paint if it deviates more than the tolerance then it is really not acceptable.
Thank you Mr.Noel for the response.
Today i received an NCR with description for the waviness in exterior walls textured paints.
During my absence the external plastered walls were not inspected via IR and been painted. When i checked the wall surface, alignments and found to be within tolerances. Now the difficulty is that the construction team doesn’t want to take out the paint for rectifying the waviness in wall/paint. Please guide me what will be the corrective measures should be taken inorder to close out the NCR.
Hope i will get answer for this.
Please advise
You are welcome.
Now, it is also NCR if you did not raise an IR before applying paint. It should have been inspected and approved by the Engineer before the application of any coats of paint.
This is my idea and perspective. Go first with the diplomatic way. If you checked the area and found the surface is within the tolerance, establish the evidence, gather the standard that shows the limit of deviation and then create a survey report that your site investigation is true. There should be something proof and evidence and then if survey report is ready bring that to the Engineer along with the standard and show to them that the wall is within the tolerance. Convince them and let you see what they will do and tell you.
Dear Sir,
I Requested method statement for UG sump step by step from excavation
UG stands for what?
How you test slump for SLAB ON GRADE….,? I think it is FLOOR PCC….Vibrator is used or not? For Floor PCC used SRC 300 Kg/cu.m.
I wrote a blog post about slump test you can search that here. PCC is not required of vibrator. Yes, sometimes 250kg/cu. m. but it depends on the approved design mix.
After backfilling works the next is casting slab on grade (ground), make sure that all the area beneath grade slab have been properly backfilled and compacted. Nice post!