Research Opens Door to Broader Use of Recycled Concrete Aggregates in ConstructionPosted: Feb 23, 2021 The limited variability of test results in this University of Wyoming research should alleviate alkali-silica reaction concerns for those who wish to use recycled concrete aggregate (RCA). The Rocky Mountain Region has experienced considerable difficulty due to the presence of alkali-silica reaction in concrete construction. As natural aggregate resources become scarce, it is increasingly attractive to use RCA as a raw material in new concrete. However, a concern with using RCA as a sustainable building material is its potential for alkali-silica reaction, particularly if the concrete was removed from service due to alkali-silica reaction. The study suggests that there was no additional variation with using RCA instead of natural aggregates. Within-laboratory variability for the concrete prism test meets the within-laboratory precision limits. So no recommendation has been proposed to modify existing ASTM within-laboratory precision limits. This research helps confirm that using RCAs combined with natural aggregates produces durable long-term concrete that will benefit the transportation network in this region. This study provides experimental data that permit RCAs to be used in applications beyond base fill for roads. Jennifer Tanner, Ph.D. |