Self-compacting concrete demonstration project.

PDFTech Report33898-4TIRESelf compacting concreteRheologyMix designHigh performance concreteTestsGirdersMeasurementLouisianaLouisiana State University. Department of Civil and Environmental EngieeringMukai, D. J.Ehrgott, John Q.Louisiana State University (Baton Rouge, La.). Dept. of Civil and Environmental EngineeringLouisiana Transportation Research CenterUS Transportation CollectionSelf-compacting concrete is a type of concrete currently being developed that does not need vibration to be placed, even in very congested areas. The primary objective of this study was to compare the rheology, or flowing characteristics, of three different self-compacting concrete mixes to a high performance concrete mix and a flowing concrete mix proportioned in accordance with ASTM C-1017-92. To this end, five simple tests were used to evaluate the rheology of the different mixes. While all five mixes exhibited high slumps, the high performance and flowing concrete mixes could not achieve the same flowability as the self-compacting concrete mixes. A full size Type-I girder model was used to determine which mixes qualified asa self-compacting, and only the mixes specifically proportioned to be self-compacting filled the girder without voids. Two different tests, a U-Test and a modified Khayat Horizontal flow tests, clearly differentiated between the self-compacting mixes and the non-self-compacting mixes. The U-Test measured the ability of the concrete to flow through a vertical gate of reinforcing steel in a U-shaped apparatus. The Horizontal test measured the ability of the concrete to flow horizontally through repeated grids of vertical and horizontal reinforcing steel. Also, the different self-compacting concrete mixes are compared and contrasted with each other, a high performance concrete mix, and a flowable concrete mix. It was found that three characteristics of self-compacting concrete are: a high cementitious material content, a low coarse aggregate content, and a high dosage of high range water reducer