There are several requirements that formwork structure need to meet otherwise it would not serve its purpose adequately. In order to make sure that the form structure fulfill its design goals, the designer and site engineer should take technical, functional, economical, and safety requirements of the forms into consideration.
The fulfillment of these requirements would guarantee safe, strong, and robust formwork structure and provide safe working condition for labors. Formwork is a temporary mould into which fresh concrete and reinforcement are placed to form a particular reinforced concrete element. It supports part or the whole of a permanent structure until it is self-supporting.
1. Technical Requirements of Formwork
- Formwork should be of the desired shape, size and fit at the location of the member in structure according to the drawings.
- It should be carefully selected for required finish surface and linings to produce the desired concrete surface.
- Formwork need to withstand the pressure of fresh concrete and working loads and should not distort or deflect from their position during the concrete placement operation.
- The formwork must not damage the concrete edge or surface; or themselves during removal from structure.
- Panels of the formwork should be tightly connected to minimize gap at the formwork connection to prevent leakage of cement paste.
2. Functional Requirements of Formwork
- Formwork sections should be sized in a manner that can be lifted and transported easily from one job site to another.
- It should be dismantled and moved as easily as possible.
- Interchangeability of formwork units is another functional requirement. This enables units to be used for forming different members.
- Formwork shall be designed such that it fits and fastens together with reasonable ease.
- Simplicity in erection is another valuable functional requirement of forms.
- Formwork should be as lightweight as possible without any strength reduction.
3. Economic Requirements of Formwork
- Formwork shall be made of low-cost materials.
- Energy consumption and labor cost should be as minimum as possible.
- Repetitive utilization of formwork is another economic requirement that must not be compromised. So, they must be able to withstand a good number of reuses without losing their shape.
- Formwork structure must be designed so that the whole formwork system can be assembled and dismantled with unskilled or semi-skilled labor.
- Maintenance of formwork is required to be conducted based on applicable standards.
4. Safety Requirements of Formwork
- Formwork needs to be manufactured such that workers can handle them without any safety issue.
- Health, safety, and hygiene regulation should be considered while forms are made.
- Stability of the whole structure should be checked and ensured to avoid any undesired events which may cause loss of life, delay construction, and increase cost.
- Emergency escape route shall be provided.
- Emergency response plan need to be established.
- All reasonably practicable steps shall be taken to eliminate any foreseeable risk arising from the work to be done.
- If it is not possible to eliminate the expected risk totally, then control measures and safe work procedures shall be implemented to minimize and control the risk.