Formwork and Falsework Safety

About this course.

Formwork is the temporary moulding into which wet concrete is placed and shaped, and falsework is the temporary supporting structure — props, frames, beams and bracing — that holds the formwork, the wet concrete and the construction loads in position until the permanent structure has hardened enough to support itself. Their failure is so often catastrophic because they carry enormous loads at the precise moment the concrete has no strength of its own; when the support gives way, tonnes of wet concrete and the collapsing structure come down suddenly and without warning, burying workers and striking anyone below. There is rarely time to escape.

To understand the hazard, it helps to picture what these temporary works actually do. A concrete slab, beam, column or wall begins life as a fluid mixture poured into a mould. Until the concrete cures and gains strength, it cannot hold its own shape or weight — it behaves, for a time, like a heavy liquid. Formwork provides the faces of the mould that give the concrete its shape and surface finish, and falsework provides everything underneath and around it that keeps that mould in exactly the right position and resists the loads pressing on it. Together they are a complete temporary structure that must be engineered, erected, loaded and dismantled with the same care as any permanent one — arguably more, because they are loaded hardest at their most vulnerable moment and are dismantled while people work close by.