Properties of self-compacting high-strength concrete containing multiple use of recycled aggregate

Abstract

Advances in recycling can exceed traditional practice in that a non-renewable resource can at least become a partially renewable resource. This research attempts to support the cradle-to-cradle concept by testing the effect of reused recycled concrete aggregates (RRCA) on the fresh, physical, mechanical, and microstructure properties of self-compacting high-strength concrete (SCHSC). Two generations of recycled aggregate concrete (RAC) are produced; the first and second are created by recycled concrete aggregate (RCA) and by RRCA, respectively. For each generation, two replacement amounts are used (25% and 50% by mass). Results show that using RRCA does not affect the fresh properties of SCHSC, and up to 50% RRCA replacement amount by mass can be adopted for enhancing the mechanical and microstructure properties of reused recycled aggregate concrete (RRAC). Computed tomography indicates that the porosity of RRCA is less than that of RCA. Keywords: Computed tomography (CT), Mechanical properties, Recycled aggregate concrete (RAC), Reused recycled aggregate concrete (RRAC), Self-compacting high-strength concrete (SCHSC)