Assessment of the variability and uncertainty of using post-customer plastics as natural aggregate replacement in concrete

Abstract This paper presents a comprehensive assessment of the performance of concrete containing post-customer plastic as natural aggregate replacement. An experimental database of 370 individual concrete mix designs is collated from 60 studies and covers a large variety of plastic aggregate types and concrete mixing factors. This database is used to: evaluate the overall variability of plastic aggregate concrete (PAC), quantify the uncertainty of applying models developed for natural aggregate concrete (NAC) to predict the compressive strength of PAC, and to identify the influential PAC mixing factors. The database is also used to develop a new design-oriented model to predict the 28-day compressive strength of each type of PAC. A significant change in the failure mechanism of PAC at different strength grades is identified based on these analyses. Moreover, comparisons of mechanical properties of PAC with models given in major design codes for conventional NAC are performed. It is shown that the existing models cannot adequately predict PAC mechanical properties due to the significant differences in the characteristics of PA and NA.