Formwork for concrete construction is used as a mould for the needed structure where the fresh concrete is poured to harden subsequently. Formworks also are named by the type of structural construction used: slab formwork, beam formwork, column formwork, columns respectively etc. Having a good formwork means that it should fill several requirements: to be strong enough to withstand every type of dead and live loads. Rigidly constructed and efficiently propped and braced (horizontally and vertically), so it can retain its shape. All used joints for the formwork should be tight against leakage of cement grout. Its construction should permit removing parts in desired sequences that will not damage the concrete. The material used for its construction should be cheap, available and suitable for reuse. It should be set accurately to the desired line and levels should have plane surface.
The framework should be as light as possible. Its material should not warp or get distorted when is exposed to the elements. It should rest on firm base. More about types, economy in the cost and similar, in the link bellow.

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