The following flowchart demonstrates the operation of our formwork business :
Level survey and setting out at the area
To ensure that the formwork will be erected in accordance with the construction drawings. It is important that the reference points and the setting out points are protected against accidental movement or damage. Incorrect reference points give incorrect deviations therefore creating unnecessary work for the formwork erection. An independent checking engineer may be called upon to measure and verify the load bearing of a formwork structure to ensure that it is of the strength required and expected.
Preparation of formwork (Note)
Plywood are cut into panels of desired size to suit the planned formwork erection. Thereafter, the formwork panels are coated with the form release agent, a kind of chemical which is used to prevent the plywood from bonding to the concrete finishes, before erection.
All formwork begins at a corner and proceeds from there. This is to provide temporary lateral stability. A single panel at a corner will give sufficient lateral support to a very long section of wall. We have to ensure all edges of the formwork or falsework system and their contact face are properly cleaned and oiled prior to be fixed in place. The formwork panels and falsework system are erected to form the mould of the walls, columns, beams and soffits. The form panels are connected by timber struts and waling with the help of nails and bolts. Timber joists are fixed at even internal to the plywood panel to support the loading against the plywood panel when concrete is poured.
The vertical and horizontal alignments are being checked to ensure the formwork erected will not deviate from the original design.
Concrete pouring (Note)
Reinforcement will be performed, fabricated and fixed in accordance with the requirements in the construction drawings and specification. The formwork will then be inspected to ensure that it is in the right alignment after such reinforcement. We have to ensure that the condition of formwork is firm enough to withstand the concreting process.
Removal of formwork
Commence after the concrete has gained the required strength. Normally, a wall formwork and column formwork can be struck after 12 hours, but the striking times vary from project to project. Materials will then be assessed for suitability for re-use.
Note: This step of the formwork sequence is executed by a party other than our Group.