Effect of the quality of parent concrete on the properties of high performance recycled aggregate concrete

摘要

This paper presents the experimental results of a study on the effect of the quality of parent concrete (PC) on the properties of recycled aggregates (RAs) that are derived from them, and on the mechanical and durability properties of normal strength and high performance recycled aggregate concrete (NSRAC and HPRAC). PC with strength grades ranging from 30 to 100 MPa was crushed to the size of coarse aggregates (＜20 mm), and then used to produce new NSRAC and HPRAC mixes. The results indicated that the compressive strength of the NSRAC and HPRAC prepared with RA derived from 80 and 100 MPa PCs was similar or slightly higher than that of natural aggregate concrete. Moreover, the concrete mixtures made with RA are derived from parent concrete with higher strength had lower drying shrinkage and higher resistance to chloride ion penetration. The RA derived from 80 and 100 MPa PCs can be used to replace 100% natural aggregates for the production of high performance concrete.