The complex interaction between cement and chemical/mineral admixtures in concrete mixturesometimes causes unpredictable concrete performance in the field, which is generally defined as concreteincompatibilities. Cement paste rheology measurements instead of traditional workability tests caneffectively those incompatibilities in concrete before the concrete is placed to avoid setting time,workability, and curing-related issues which sometimes leads to severe early-age cracking especially insevere weather conditions. The objective of the present study was to examine the applicability of theSuperpave Dynamic Shear Rheometer (DSR) to measure cement paste rheology in one hand andidentifying cement and mineral/chemical admixtures incompatibilities based on cement paste rheologicalbehavior on the other hand. Based on the extensive laboratory investigation, it is observed that DSR inmodified form can measure cement paste rheology with permissible repeatability and sensitivity and has agreat potential to identify cement and mineral/chemical admixture incompatibilities. The heat ofhydration data from isothermal calorimeter test and setting time results for the studied mixtures hasstrongly supported the rheology results. A procedure to formulate rheology-based acceptance criteria hasbeen developed based on the available test results. Further refinement of these acceptance criteria basedon detailed work covering wide range of incompatibilities and validation through round robin testingprogram is warranted. This will ultimately help concrete producers and district laboratories to detectproblematic combinations of concrete ingredients during the mixture design process.
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