Comparative analysis of existing prediction models on the creep behaviour of recycled aggregate concrete

• State of the art review on the effect of recycled aggregates in concrete creep.
• Correction factors proposal for creep increase with recycled aggregate content.
• Application and viability of existing prediction models for compliance in RAC.
• The ACI 209R prediction model demonstrated the best results in terms of accuracy.

This paper provides a systematic literature review, based on the identification, appraisal, selection and synthesis of publications relating to the effect of incorporating recycled aggregates sourced from construction and demolition wastes, on the creep behaviour of concrete. It identifies various influencing aspects related to the use of recycled aggregates such as replacement level, size and origin, as well as mixing procedure, exposure to different environmental conditions, use of chemical admixtures and additions, and creep of recycled aggregate concrete after unloading. A statistical analysis on the collated data is also presented with the purpose of understanding the creep behaviour of concrete, based on the replacement level of recycled aggregates. The evidence gathered was also compared to a model for compliance prediction. Correction factors of the creep coefficient of concrete with varying recycled aggregate content are presented in this paper. Some of the prediction models are feasible for use in recycled aggregate concrete.