Effect of carbonation of modeled recycled coarse aggregate on the mechanical properties of modeled recycled aggregate concrete

Long Li, Jianzhuang Xiao, Dongxing Xuan, Chi Sun Poon

Research output: Journal article publicationJournal articleAcademic researchpeer-review

42 Citations (Scopus)


The modeled recycled aggregate concrete (MRAC) which is an idealized model for the real recycled aggregate concrete (RAC) was used in this study. The MRCAs prepared with two types of old mortars were modified by an accelerated carbonation process. The effects of carbonation of MRCA on the micro-hardness of MRCA and the mechanical properties of MRAC were investigated. The results indicated that the micro-hardness of the old interfacial transition zone (ITZ) and the old mortar in the carbonated MRCAs was higher than that in the uncarbonated MRCAs, and the enhancement of the old ITZ was more significant than that of the old mortar. The compressive strength and modulus of MRACs increased when the carbonated MRCAs were utilized, and the improvement was more significant for MRAC prepared with a higher w/c. In addition, a numerical study was carried out and it showed that the improvement in strength by carbonation treatment was less obvious when the difference between the new and old mortar was larger.

Original languageEnglish
Pages (from-to)169-180
Number of pages12
JournalCement and Concrete Composites
Publication statusPublished - 1 May 2018


  • Carbonation treatment
  • Compressive strength
  • Micro-hardness
  • Modeled recycled aggregate concrete (MRAC)
  • Simulation
  • Water-to-cement ratio

ASJC Scopus subject areas

  • Building and Construction
  • Materials Science(all)

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