Evaluation of ASR Potential in Wyoming Aggregates and the Stiffness Damage Test as a Method for Assessing Expansion in ASR Affected Concret

The ASR potential of eight different aggregate sources in Wyoming was analyzed as part of a project partially funded by the Wyoming Department of Transportation (WYDOT). The aggregates were subjected to the Accelerated Mortar Bar Test (AMBT) using three different concrete proportions: fines, crushed coarse and a 40 to 60 percent combination of fine to crushed coarse fractions. AMBT results were compared to previous findings to evaluate any variations in behavior when testing different size fractions of aggregate. A discussion of the correlation between the AMBT and Concrete Prism Test (CPT) results is presented. Petrographic analysis of aggregate previously classified as reactive was used to confirm the presence of ASR gel. The Stiffness Damage Test (SDT) was used to assess expansion in concrete damaged by ASR. Several potential parameters were used to examine the effectiveness of the SDT to predict measured expansions. Hysteresis area, plastic deformations and the modulus of elasticity provided good correlation to the amount of expansion experienced in the concrete.