What Are the Causes of Pitting in Concrete?
On rare occasions, premature pitting and degradation of a concrete slab can be attributed to an aggregate that is not suitable for use in concrete. This scenario typically happens quickly and in a variety of conditions and can usually only be determined in a lab. A bad aggregate will either create a chemical reaction that breaks down the concrete or has excess porosity that poorly resists the freeze-thaw cycle. Concrete materials are standardized and tested. If something slips through, many times it is from a small vein of material in the rock quarry that goes unnoticed.
