Method for evaluating segregation in self-consolidating concrete using electrical resistivity measurements

摘要

Self-consolidating concrete requires a highly fluid binder with sufficient segregation resistance in the fresh mixture. However, careless mix proportioning with various chemical and mineral admixtures can cause instability among the components in the fresh state, including aggregate segregation. The fully or partially segregated mix expectedly exhibits low durability after it hardens. This study attempted to nondestructively evaluate the degree of static segregation in self-consolidating concrete. A column type test mold was fabricated, which allowed cross-sectional electrical resistivity to be measured in the top and bottom sections using a total of 24 electrodes. The electrical resistivity can sensitively evaluate the relative degree of segregation in concrete mixtures. The experimental results were also compared and discussed using the coarse aggregate segregation index obtained using the conventional method, that requires wet-sieving of self-consolidating concrete in the fresh state. (C) 2019 Elsevier Ltd. All rights reserved.