Shrinkage and porosity in concretes produced with recycled concrete aggregate and rice husk ash

  • Vinício Cecconello Universidade do Vale do Rio dos Sinos - Unisinos.
  • Bruno Rommel Cattani Sartori Universidade do Vale do Rio dos Sinos - Unisinos.
  • Marlova Piva Kulakowski Universidade do Vale do Rio dos Sinos - Unisinos.
  • Claudio de Souza Kazmierczak Universidade do Vale do Rio dos Sinos - Unisinos.
  • Maurício Mancio Universidade do Vale do Rio dos Sinos - Unisinos.

Abstract

The admixture of recycled concrete aggregates (RCA) in new concretes is an interesting alternative in the efforts to mitigate environmental impacts. RCA may increase porosity and change properties of concretes. Rice husk ash (RHA) is employed as supplementary cementitious material may improve concrete properties. The present study investigated the shrinkage of concrete prepared with RCA and RHA, proposing a mathematical model to explain the phenomenon. Concretes were produced with 25% and 50% of coarse recycled aggregate as replacement of natural aggregate, 0%, 10%, and 20% of RHA as replacement of cement, and a water-to-binder ratio of 0.64. Water absorption and capillary and total porosities were analyzed on day 28. Shrinkage tests were conducted on days 1, 4, 7, 14, 28, 63, 91, and 112. The results point to a significant interaction between RHA and RCA.
Published
Mar 19, 2019
How to Cite
CECCONELLO, Vinício et al. Shrinkage and porosity in concretes produced with recycled concrete aggregate and rice husk ash. RIEM - IBRACON Structures and Materials Journal, [S.l.], v. 12, n. 3, mar. 2019. ISSN 1983-4195. Available at: <http://revistas.ibracon.org.br/index.php/riem/article/view/1163>. Date accessed: 20 june 2019.
Section
Artigos