Characterization of concrete affected by delayed ettringite formation using the stiffness damage test

The stiffness damage test (SDT) may provide more information than conventional mechanical tests used to assess concrete affected by expansive reactions. A new approach to analyzing SDT data involving the calculation of stiffness damage and plastic damage indices (SDI and PDI) has successfully characterized the expansion of concrete affected by alkali-silica reaction (ASR). This study is the first to implement SDI and PDI to characterize concrete affected by delayed ettringite formation (DEF). The SDI and PDI parameters have a nearly linear relationship to expansions under 0.40%. ANOVA confirms the statistical significance of the SDI and PDI parameters and that they provide information not available from standard elastic modulus tests.