Title: Crystal Growth In Entrained-Air Voids
Author(s): Bryant Mather
Publication: Symposium Paper
Appears on pages(s): 105-106
Crystals are found in some entrained-air voids of all concrete that has been "left out in the rain" or stored while damp. These crystals can be observed through petrographic examination of thin or ground concrete sections at normal magnification. If the concrete was made using a cement with a high tricalcium aluminate (C3A) content (over 8%), it is likely that areas in it will be covered with ettringite crystals - secondary ettringite.