What are formworks?

Formworks (or Forms) are an arrangement of wooden boards, bolts, etc., used to shape reinforced concrete while it is setting. They are also known as Shuttering. The conventional formworks are made of wood or metals like steel or aluminum.

Functions:

1. Forms mould the concrete to desired size and shape and control its position and alignment. 
2. Formworks also act as a temporary structure that support its own weight + the freshly placed concrete + live loads (material, human, equipment).

Formwork is a perfect temporary structure as:

1. It can be erected quickly. 
2. Highly loaded for a few hours during the concrete placement. 
3. Within a few days it is disassembled for future use.

A good formwork would have the following characteristics that is:

• Safe 
• Cost effective or economical 
• High Quality – finished concrete surface is of acceptable quality (position and size)

Common Material for Formwork Construction:

1. Timber 
2. Steel 
3. Glass Reinforced Plastic 
4. Aluminum

In this article, we are going to discuss about another material – Plastic Formworks – and its advantages over conventional materials.

Advantages of Plastic Formworks over traditional Wood/Steel are:

• Plastic formwork can be used more than 100 times (if handled properly), which is not possible with timber.
• The panels are light weight, sturdy and easier to handle than steel or timber.
• The concrete does not stick to it; making it easy to clean after use just by spraying water.
• No shuttering oil is required as the surface tension is low and the concrete does not stick. In slabs though
one can brush the form panels with oil since the panels would be fixed for a longer period of time.
• Unlike steel and timer, plastic is neither damaged in water nor their is the problem of rusting.
• It can be locked by a locking handle which ensures tight fixation of panels that ensures no leakage of
concrete; thus by joining the panels it makes it one single panel. Hence locking the panel is easier and more
accurate than the arrangement in timber and steel.

A typical Plastic Form for a concrete wall

(Salient Features: Ensures zero seepage of concrete mix and water, Accurate angles maintained, Easy to ensure locking arrangement, Easy maintenance and cleaning of plasforms etc.)

• It ensures a good finish of walls, slabs, columns, beams etc. reducing the need to plaster the surfaces.
• Its saves a lot of time and labor as it is easy to fix and hence results in financial savings.
• The panels are multi purpose as they can be used in all the elements namely walls, columns, slabs and beams.
• Even after being comparatively expensive than the timber or steel it still works out much cheaper due to its
repeatability and finish.
• These panels can be used to replace the brick walls by using this to make the total shuttering and then cast the
foamed concrete or low weight cellular concrete, which can be pumped directly into the situ.
• You do not need nails to fix them and over all it is eco friendly and can be recycled.

Plastic formworks are produced by the following companies:

1. Geoplast S.p.A, Padova, Italy (http://www.geoplast.it/eng/)
2. Moladi, Port Elizabeth, South Africa (http://www.moladi.net/)
3. NOVA Plas Mold Pvt. Ltd., India (http://www.starpac.in/index.php/products/plastic-formwork-system)

A typical Plastic formwork (requires minimum fixing arrangement and is versatile)

A typical Timber formwork (requires specific fixing arrangement with anchor hook)

Plastic formwork are versatile and can be used for a wide range of shapes with ease

Plastic formwork for pavements and roads. (Widely used for landscaping with minimised labor cost)

Frames for mullions are also very easy to make with plastic formwork

References:

• Aggregate Research (http://www.aggregateresearch.com/)
• Plasmix (http://www.plasmix.in/index.php)
• GEOPLAST (http://www.geoplast.it/eng/)
• moladi construction (http://www.moladi.net/)
• NOVA Plas (http://www.starpac.in/index.php/products/plastic-formwork-system)