I am a civil engineer in a construction enterprise in Tangshan, and I would like to ask if there is a minimum carbonation depth of concrete. Please ask the master for advice.

Concrete has no minimum carbonation depth. The smaller the better, the slower the development of carbonization depth. The carbonation of concrete is because calcium hydroxide in concrete reacts with carbon dioxide in the air to produce calcium carbonate, and the PH value decreases, and the carbonation shrinkage cracks cause the corrosion of steel bars in concrete. Carbonization of concrete is the basis of the thickness of reinforced protective layer.