Ground beam is commonly used by a structural engineer for the design of a concrete building in order to withstand the sudden change of level of any part of the ground slab. Practically, settlement cannot be avoided but it can be minimized. This is used to achieve a tolerable amount of settlement when there is earth-shaking or earth movement.
It is much better if the building settles at equal amount of displacement or what we call settlement.
So without further ado here is the method statement for construction of ground beams.
Method Statement for Construction of Ground Beams
2. Purpose and Scope
This method statement describes how to install the ground beams’ reinforced concrete in order to meet project requirements.
• Shop drawing (Reference no. here)
• Specification (Reference no. here)
• Trial mix & supplier approval
• Concrete (Grade here)
• Steel rebar (Sizes here)
• Construction Manager
• Project Engineer
• Site Engineer
• Surveyor with helper
• Safety officer with helpers
• Skilled/unskilled labors
• Equipment operator
• Steel Fixers
• Skilled Laborer
6. Equipment and tools
• Total station
• Level machine
• Water tanker
• Concrete pumps
• Concrete trucks
• Concrete vibrators
• The Construction Manager has the overarching responsibility to implement the method statement of ground beams RCC. He must ensure the adequate education of Engineers and foremen regarding this method statement and the immediate availability of all resources – human, material and equipment – so the plan proceeds without unnecessary delays.
• Ensures on-site availability of all the required manpower and equipment.
• Oversees his on-site team, including site engineers, surveyors, and foremen.
• Provides his site team with final drawings for execution.
• Deals with the supplier of the ready-mix regarding concrete quantity and delivery.
• Monitors the casting operation.
• Ensures the preparation of the curing process.
• Ensures that the safety requirements are met on site.
• Checks the reinforcement steel as per approved drawings and materials such as beam type, length, bars diameter, spacing, number, overlap for the bottom, side, top, extra reinforcement steel, stirrups number, shape and spacing, concrete cover blocks or spacers and the stiffener columns reinforcement steel.
• Checks with MEP coordinator before closing the shutter for any MEP works to be installed.
• Prepares the reinforcement steel’s inspection request and checklist as per ITP.
• Check the shutter works of ground beams including shutter materials, shutter alignment, concrete, shutter support and cleaning inside the shutter.
• Deals with the approved testing laboratory supervisor regarding the cubes compressive test.
• Deals with the lab supervisor of the ready-mix supplier for the number of cubes.
• Conducts checkup for the concrete truck such as climate temperature, slump test, and concrete temperature.
8.1 Steel Reinforcement and Shuttering:
8.1.1. First finish the required blinding plus waterproof asphalt underneath the ground beams.
8.1.2. Make sure that the cut and the bent steel schedules are prepared, submitted and approved by the Engineer.
8.1.3. Make sure that the cut and bend materials reach the site in good condition for each building separately as per cut and bent schedules.
8.1.4. Deposit the delivered materials properly near each related building, covered appropriately.
8.1.5. Discard any rusted bars.
8.1.6. Use approved shop drawings by Engineer to start reinforcement installation.
8.1.7. Follow the reinforcement layouts, sections and schedules to fix the steel.
8.1.8. Fix the reinforcement steel of the stiffener columns as per approved layouts and dimensions.
8.1.9. Bind the steel properly.
8.1.10. Reject any loose binders in the reinforcement steel.
8.1.11. Bent the free ends of the binding wire inward.
8.1.12. Use stirrups to tight the steel properly.
8.1.13. Discard any loose stirrups.
8.1.14. Ensure the stirrups are fixed as per approved drawings.
8.1.15. Fix the stirrups straight and aligned.
8.1.16. Fix the compressible filler board according to the thickness stated in the approved drawings for expansion joints.
8.1.17. Use tips coated metal chairs for the horizontal bars and circular spacers for verticals bars as a concrete cover.
8.1.18. Clear all the items relating to MEP works necessary according to approved MEP drawings.
8.1.19. MEP Engineer shall check and approve all MEP works prior to shutter closure.
8.1.20. The Engineer shall check and approve the reinforcement steel of ground beams before closing the shutter, and also the stiffener columns’ reinforcement.
8.1.21. Shutter works is ongoing as per approved layouts and dimensions.
8.1.22. Use proper materials.
8.1.23. Discard all damaged materials intended for shutter works.
8.1.24. Treat all forms with oil and saturate with water immediately before concrete placement.
8.1.25. Conduct proper fixing, alignment and leveling of the forms of the ground beams before concreting as per approved drawings.
8.1.26. Properly and accurately support the forms to avoid and prevent any distortion due to the pressure of the concrete.
87.1.27. Fix the required concrete level of ground beams before casting.
8.1.28. Use polythene sheets to cover the stiffener columns reinforcement steel to prevent any concrete touch during casting.
8.1.29. Make sure that the forms are totally clean and clear of any obstructions, missed tools, binding wires, loose cover blocks or spacers.
8.1.30. Use an air compressor to clean the forms from any dust or soil gathered inside before concreting.
8.1.31. The forms will be checked and approved by the Engineer before casting.
8.2 Concreting Stage:
8.2.1. A sketch shall be drawn by the contractor that will display the casting areas, pump location, pump and trucks access and concrete trucks checkpoints, which will be submitted to the Engineer.
8.2.2. The concrete trucks will stop at the checkpoints for inspection, such as slump test and cubes made.
8.2.3. The slump must follow the pre-approved mix design.
8.2.4. A set of six cubes shall be tested after 50 cubic meters (but that depends on your specification). Three at the 7-days test and the remaining at the 28-days test.
8.2.5. An additional three cubes can be made to avoid any doubt in the regular cubes test.
8.2.6. The concrete must be unloaded from the concrete truck within two hours from the plant loading.
8.2.7. During the concreting operation, mechanical vibrators shall be used to properly compact the concrete.
8.2.8. To deal with unexpected failures, additional vibrators must be readily available.
8.3 Curing Stage:
8.3.1. Proper curing of the casted area includes covering the concrete with wet hessian cloth and polythene sheets.
8.3.2. Curing should take place 4-5 times daily for at least 10 days.
8.3.3. Clean and clear water must be used for the curing process. Alternatively, apply waterproofing asphalt.
9.1. Provide staff and laborers with all safety equipment, including safety helmet, safety shoes overalls, gloves, goggles, vests etc.
9.2. Safety precautions, such as warning tapes, signboards and barricades, shall apply from the site entrance gate, including the trucks access and pump, to the casting area surroundings.
9.3. Proper light must be available in case there is any night concreting.
9.4. The casting area shall be protected; to avoid damages, use proper barrier.
End of Method Statement