NATURAL CARBONATION OF MULTIPLELY RECYCLED AGGREGATE CONCRETE

Author(s): C.J. Zega , J.M. Etcheverry, Y.A. Villagrán-Zaccardi
Paper category: Proceedings
Book title: CO2STO2019 - International Workshop CO2 Storage in Concrete
Editor(s): Assia Djerbi, Othman Omikrine-Metalssi, Teddy Fen-Chong
ISBN:
e-ISBN: 978-2-35158-232-9
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 109-115
Total Pages: 7
Language : English

Abstract: Recycling of concrete is a widespread practice in many countries. Documentation of this
practice is not always feasible, and in some cases, waste concrete might have been already
produced with recycled concrete aggregates. The conventional concrete design method will
originate concretes with increasing mortar content with successive recycling. With a lower
content of stone, this situation may result in a significant affectation of the durability of the
concrete being produced, including carbonation. In this paper, recycled aggregate concrete
was produced with coarse recycled concrete aggregates obtained from successively recycling
concrete up to five times. Each time, 75% vol. of the total content of coarse aggregate was
consisting of recycled concrete aggregate from the preceding concrete. The successive
recycling process produced not only an increasing content of mortar in the resulting concrete,
but also a multiplicity of interfacial transition zones. Natural carbonation of samples exposed
in La Plata city, Argentina, was evaluated after 14 years of exposure. The carbonation depth
is contrasted with transport and mechanical properties in order to verify prediction models
based on technological properties of concrete evaluated at 28 days of age.

Online publication : 2019
Publication type : full_text
Public price (Euros) : 0.00