International Concrete Abstracts Portal

Title: Properties of Concrete with Recycled Concrete Coarse Aggregates

Author(s): A.M. Buttler and E.F. Machado, Jr.

Publication: Special Publication

Volume: 229

Issue:

Appears on pages(s): 497-510

Keywords: physical and mechanical properties; recycled coarse aggregate; recycled concrete

Date: 9/1/2005

Abstract:
A great quantity of construction and demolition wastes are produced every day in Brazil, representing about 60% of the total solid waste stream. A high proportion of demolition waste, particularly the fraction derived from concrete, is well suited to being crushed and recycled as a substitute for natural aggregates. This paper presents the results of an experimental study to evaluate the physical properties of the recycled concrete coarse aggregates and the physical and mechanical properties of the concretes produced with these aggregates. Results indicate that the residues of concrete that were recycled right after generation exhibit higher compressive and tensile strengths when compared to those concretes with natural aggregates because of the presence of a large amount of nonhydrated cement particles. On the other hand, the mechanical properties of recycled aggregate concrete (for example, modulus of elasticity and drying shrinkage) were not as favorable when compared to reference concrete.