Delayed Ettringite Formation

• The primary ettringite formation during the initial hydration does not lead to damage, because this ettringite formation occurs in the plastic matrix and thus no stresses will be produced.
• If the ettringite formed primarily or delayed inside the micro-structure is micro-crystalline, than in hardened concrete it may develop an expansion pressure due to adsorption of water, which can cause damages if the tensile strength of the micro-structure is exceeded.