Built from plywood, lumber, aluminum or steel panels with ties, walers and shores, formwork has to resist the full fluid pressure of fresh concrete plus the weight of crews and equipment. It is often the largest labor and cost item on a cast-in-place job, so contractors reuse gang forms and engineered panel systems wherever they can. Forms come off only after the concrete reaches the strength the engineer requires.
Formwork on the shear walls has to be plumbed and the ties checked by noon if we want to pour tomorrow.
Also heard as
- forms
- forming
Related terms
Blowout
A form failure where formwork bursts open or shifts under the pressure of fresh concrete.
Lift
One layer of concrete placed in a wall, column or mass pour, or the height cast between horizontal joints.
Bugholes
Small surface pits on vertical formed concrete left by air bubbles trapped against the form face.
Embeds
Steel plates, anchor bolts, sleeves and inserts cast into concrete for connections made later.