The work presented in this paper is part of a comprehensive study to evaluate the feasibility and performance of self-consolidating concrete (SCC) made with South Dakota local aggregates, and to develop SCC draft specifications, acceptance criteria, mix qualifications, and guidelines that the South Dakota Department of Transportation (SDDOT) can use for the construction of precast and cast-in-place non-prestressed structural applications. This paper summarizes the experimental results of a study to assess the fresh and hardened properties of the SCC mixtures that were prepared in the laboratory. Twelve SCC mixes were studied. The parameters were aggregate type, water-to-cementitious material ratio (w/cm), and mixing duration. The mixes were developed for two types of coarse aggregates: quartzite from eastern South Dakota, and limestone from western South Dakota. Two mixing durations were utilized to simulate precast and cast-in-place applications. Three w/cm ratios, 0.38, 0.42, and 0.46, were investigated. The experimental results show that South Dakota local aggregates having proper shape and size can be used to produce stable SCC. For cast-in-place applications, better control of SCC flowability can be achieved when the high range water reducing admixture (HRWRA) is added and mixed immediately before concrete discharge. It was observed that a longer mixing duration resulted in higher air content. The strength characteristics of the hardened SCC in this research followed a trend similar to that of conventional concrete.
Samenvatting