I plan on water-curing a concrete slab (4' x 8' x 4"). I figured I would just spray it with some water to keep it wet. How often do I need to spray water on the slab? When should I start spraying it?
Cover fresh concrete with some foil to prevent the water from evaporating. After one day you can start to spray. The duration depends on the quality of the concrete. It could be from one to seven days.
The most important part is to keep the concrete wet so there is enough water for the hardening process.