Wet concrete pushes on forms like a heavy fluid, about 150 lb per sq ft for every foot of depth, so pouring too fast, overvibrating, missing ties or weak bracing can split a panel or pop a tie. A blowout dumps concrete, throws the wall out of line and stops the pour while the crew patches and braces. Someone watching ties and bracing during the placement is standard practice on wall pours.
We had a blowout at the corner, shut the pump down and get some 2x4s and screw jacks over here.
Also heard as
- form failure
- blew out
- blowing a form
Related terms
Formwork
The temporary molds, supports and bracing that hold fresh concrete in shape until it can carry itself.
Lift
One layer of concrete placed in a wall, column or mass pour, or the height cast between horizontal joints.
Stinger
An internal concrete vibrator, or specifically the vibrating head on the end of its flexible shaft.
Pour
The act of placing concrete, or one placement itself, in everyday jobsite speech.