1. Scope:
The intention of this document is to describe the various steps involved to be carried out during the erection of formworks for various concrete elements.
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2. Relevant Process/Specifications:
Tender Specifications
3. Tools and Equipment:
Carpentry tools, wood cutting machine, spirit level, rubber hammer, etc.
4. Procedure:
ADVERTISEMENTS:
Prior to commencement of all construction activities, necessary work permits shall be obtained.
All materials identified for the permanent work shall be approved by the Company, prior to the procurement.
All HSE activities related to the project will be based on the Company issued HSE Management System Guidelines.
ADVERTISEMENTS:
All Quality Assurance and Quality Control Activities will be on line with the specified requirements of the Contract.
5. Form Materials:
Conform to requirements of ACI 30, 318 and 347 unless stated otherwise.
For exposed (painted or unpainted) concrete surfaces use smooth faced undamaged plywood or other panel type materials producing a finish acceptable to the Engineer or Engineer’s Representative. Panels shall provide continuous straight, smooth as cast surfaces and shall be in largest practicable sizes to minimize the number of joints.
Grooves in exposed concrete to terminate the protection membrane shall be formed by attaching tapered planed timber battens accurately aligned, to the face of formwork.
ADVERTISEMENTS:
For concealed surfaces use sound grade, rough sawn boards, to provide a mechanical bond to receive plaster (where plaster work is indicated).
Form ties shall be factory fabricated, adjustable length, removable or snap off metal form ties, cone ends, designed to prevent formwork deflection and to prevent spilling concrete surfaces on removal. No metal will be left closer than 38 mm to the surface of the concrete. Do not leave a hole largest than 10 mm diameter in the concrete surface, when using snap ties.
Form coatings: commercial foundation form-coating compounds that will not bond with, stain, nor adversely affect concrete surface requiring bond or adhesion, nor impede the wetting of surfaces to be cured.
Fillet/Chamfer Strips: PVC or timber to approval.
Formwork for wall shutters: shall be with GAP wall shutter with gel coating in inner-side to have smooth surface.
6. Execution:
Formwork Erection:
Verify lines, levels and measurement before proceeding with formwork.
Hand trim sides and bottom of earth forms, remove loose dirt.
Align form joints.
Do not apply form release agent where concrete surfaces receive special finishes or applied coatings, which may be affected by agent. Avoid contact with reinforcement.
Co-ordinate work of other sections in forming and setting openings, slots, recesses, chases, sleeves, bolts, anchors and other inserts position ties passing through concrete to approval of Company’s Engineer
Where part of a metal tie remains embedded in concrete, it shall not have less cover than reinforcement. Fill holes with concrete or mortar.
Position chamfer molding strips on exposed corners of columns and beams.
Depth of beams at all points in the span shall be as indicated.
Strip formwork carefully to avoid sudden shocks from removal of wedges or vibration, which might damage concrete.
Where finished surfaces have re-entrant angles, remove formwork as early as possible to avoid shrinkage cracks.
Place re-shoring to beams and slabs, immediately after stripping formwork
Where re-shoring is required for early stripping whilst minimizing sag or creep, the capacity and spacing of such re-shore shall be adequate for the purpose.