The nozzleman builds the section up in passes on slopes, tunnel linings, pools, retaining walls and repairs, often against a single-sided form. In the wet-mix process ready-mixed concrete is pumped to the nozzle and air is added there; in the dry-mix process, also called gunite, dry material is blown through the hose and the nozzleman adds water at the tip. Material that bounces off, called rebound, is waste and must never be worked back into the wall.
Heard on the job
Shotcrete crew's on the pool tomorrow, so have the steel inspected and the rebound from the last shoot cleaned off the deck tonight.
Insider tip
The nozzleman's hands decide the quality of the wall, which is why specs ask for certified nozzlemen and preconstruction test panels.
Also heard as
- gunite
- sprayed concrete
- gunned concrete