Title: Performance and Properties of Structural Concrete Made with Recycled Concrete Aggregate

Author(s): Ahmad Shayan and Aimin Xu

Publication: Materials Journal

Volume: 100

Issue: 5

Appears on pages(s): 371-380

Keywords: aggregate; alkali-aggregate reaction; chloride; concrete; corrosion resistance; durability; high strength.

DOI: 10.14359/12812

Date: 9/1/2003

Abstract:
Previous investigations on recycled concrete aggregate (RCA) have largely been limited to the manufacture of nonstructural-grade concrete of up to 32 MPa-strength grade, due to undesirable physical properties of RCA—for example, high water absorption leading to high water demand of concrete. The restriction seriously limits its market and consequently diminishes the use of RCA as a construction material. The use of RCA in higher-strength (50 MPa) structural concrete has beneficial environmental consequences by further conserving rock resources currently used to produce concrete aggregate. This study attempts to improve the surface properties of RCA and report on the influence of the improved RCA on the strength development and durability properties of 50 MPa-strength grade concrete. In addition to strength development, drying shrinkage, alkali-aggregate reaction (AAR), sulfate resistance, and chloride permeability were also investigated. The results are encouraging and show that RCA can be used to produce 50 MPa structural concrete with durability properties similar to those of concrete made with virgin aggregate.