Recycled Concrete in Weak Acidic Environments

Abstract:

Literature often concludes that the drop in mechanical properties of recycled concrete, compared to concrete made with natural aggregates, is unfavourable for concrete durability in aggressive environments. The agricultural industry is one of these environments where concrete floorboards and walls are confronted with weak organic acids. A research program was undertaken to determine the resistance of concrete, made with coarse recycled concrete aggregates (0-75%), against these acids. In this research two different qualities of recycled aggregates were used: while the first originated from road demolition and contained porphyry as main aggregate, the latter originated from mixed demolition and contained mostly limestone. One reference concrete mixture and six different recycled mixtures were made. These seven concretes were exposed to three different acids: acetic, tartaric and citric acid. Beside the acidic resistance tests, workability, density (fresh and hardened) and water absorption (both by capillarity and submersion) were also determined for each mixture. The results show that the increase of acid soluble material increases the resistance of concrete against erosion due to weak acids.

• Periodical: Key Engineering Materials (Volume 677)
• Pages: 224-232
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.677.224
• Online since: January 2016
• Authors: Miquel Joseph*, Luc Boehme, Christel Cornelly, Ian Anseeuw, Wouter Declercq, Lucie Vandenwalle
• Keywords: Acidic Environment, Durability, Recycling

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