Method Statement for Formwork

formwork method statement

Scope

Method Statement for Formwork defines the installation of formwork and the controls that must be performed during assembly, erection, and final positioning of shutters for structural concrete activity.

References

Project Specifications
Formwork System
Approved Shop Drawings
Material Approval
Lifting Plan & Procedure
HSE Plan-Health, Safety & Environment Plan
Project Quality Plan
BS 8666: 2020

Tools

Total station
Level machine
Plywood base plates
Water level
Nylon chord
Masking tape
Spanners

Equipment

Mobile Crane/Tower Crane

Formwork Design Requirements

The construction drawings indicate the structure’s dimensions.

During or after concrete pour, the formwork must remain stable (both vertically and laterally).

Surface finishing should conform to the type required. Concrete formwork should allow for proper placement and vibration.

Formwork must be well-tight to prevent mortar loss and concrete surface deformation.

In multi-story structures, the formwork must withstand the pressure of wet concrete, dead and live loads, and reshoring loads during concrete placement.

All embedded items must be supported solidly and inaccurate positions according to construction drawings.

Shutter Ties

Formwork will be tied at intervals that will not allow it to move or deform beyond the specified tolerance limits.

Forms for small section elements, such as columns, should be tied externally.

Through-ties must be used for large area forms.

Coating

Concrete forms must be cleaned and any foreign material removed before concreting.

The formwork shall be provided with openings so that foreign materials can be removed if necessary.

It will be coated with the approved release agent before the formwork is placed.

The properties and coating procedure must be in accordance with project specifications.

Propping and Shoring

Propping and shoring requirements shall be submitted to the consultant for approval.

Procedure

All formwork tasks will be carried out according to the specifications during reinforced concrete construction.

If necessary, the Project Engineer will consult the Structural Engineer regarding the size, type, and the number of formwork to be used in accordance with the structural drawings. The number of repetitions will be determined by the program.

For specific systems, external designers may be needed.

Formwork availability will be checked with the procurement department and a decision will be made whether to buy, hire, or repurpose formwork.

During the fabrication of shutters, all dimensions should be cross-checked to avoid having to make corrections during the erection process.

Make sure that the props, shores, waling, bearers, clamps, and tie rods are the right size and at the right spacing. The Formwork designer shall check the falsework system with respect to the loads imposed on it and design parameters, as specified in the specifications.

Make sure the concrete form is securely braced and on a stable foundation during construction.

It is essential to firmly fix forms to previously cast concrete to prevent grout loss. The seal can be made by using cellular foam plastic strips.

installation of formworks for slabs and columns
Installation of the formworks for slabs, beams, and columns for reinforced structure

Inspect the quality of the shutter lining, the tightness of bolts and wedges, and the embedded items and inserts.

The tie-rod holes in the concrete formwork should be neat so they can later be patched or plugged.

It will be vital to pay attention to the rigidity of the stop ends and the line of the joint formers.

Be sure to remove all tie-wire clippings and nails, which may stain both the formwork and concrete.

The falsework should be stable and securely braced prior to concrete pouring.

Slabs, walls, columns, beams, joists, and concrete stair shutters will be provided with integral scaffolding and shoring.

Make sure that toe boards and guardrails are provided for the concreting gang, as well as adequate access and working platforms.

Spreaders and lifting beams should be used when placing form work to avoid distortion.

The erection of adjustable steel props shall be plumb and the verticality of the props should be checked with a spirit level.

Props that are bent, creased, or rusted should not be used, as well as those with bent heads, damaged pins, etc.

The release agent should be used properly so that it can be removed without damaging the surface finish of the concrete.

The first coat of release agent should be applied to new plywood and timber formwork 36 hours in advance, followed by the second coat just before they are used. Use the release agent sparingly so as not to stain or delay the concrete.

Wedge and fastening locations should be closely monitored. Ensure that they do not become loose. Grout loss indicates movement.

Unsleeved tie bars should be eased slightly before concrete sets, and then removed after its setting.

Formwork Removal

Be sure to obtain approval from the consultant before striking formwork for concrete work.

Make sure the concrete has reached minimum sufficient strength before removing the formwork.

While removing the formwork, ensure adequate safety measures are taken.

Forms shall be cleaned as soon as they have been struck.

A good storage system is crucial to ensure that the formwork can be reused.

Identify them easily when they are needed by painting code numbers on them.

Removal of shuttering / deshuttering time period should be as detailed below:

Walls, columns, and vertical sides of the beams24-48 hours
Beam soffits 7days
Removal of props under the slab spanning up to 4.5 m7 days
Removal of props under the slab spanning more than 4.5 m14 days
Removal of props under beams and arches spanning up to 4.5 m14 days
Removal of props under beams and arches spanning over 4.5 m 21 days

Essential Form Configurations

The outline configuration of the Method Statement for Formworks to be implemented are further hereto:

  • All works will be performed using timber formwork.
  • A 18mm laminated plyboard will be used for the main panel of the form. In the case of minor items, a thinner form might be used.
  • Forms will be constructed so that they can withstand pressures from fresh concrete and to ensure that they are water-tight in any case.
  • Aluminum and/or timber beams will be fixed along the length and width of the planks to stiffen the panels.
  • In cases where the form is taller than 1.5 m, steel soldiers may be used to hold the panels together.
  • A 25mm chamfer will be formed on the external corners of structures above ground level.
  • Openings will be provided for vertical elements like walls, etc., to facilitate pouring in and compacting.
  • Rebar will be supported with the correct coverings using cover blocks made of the same mix as the parent material.
  • Stripping of forms will be done very carefully so that no damage is caused to the casted structure.
  • The quality assurance for formwork will be followed as per the approved inspection and test plan.

Safe Work Method Statement for Formwork Process

It is advisable to mark the weight of large prefabricated sections of formwork so that the crane’s lifting capacity is not exceeded at the working radius. A lifting point is usually provided.

In order to prevent distortion, a spreader or lifting beam should be used.

If the vertical soldiers are lifting, make sure they are properly connected to the waling.

Close to the stored formwork should be fire extinguishers in working order.

Attachments-Method Statement for Formwork

ITP Checklist

Inspection Form

Risk Assessment

Tags:

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removal, forms, supports, form work, propping, fabric formwork, clamps , tie, coating, work method statement formwork, safety, concrete construction, plywood, plyboard, formwork
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