Title: Functional Equivalency in the Comparative Life Cycle Assessment of Solid Waste Concrete: Implication of Mechanical Performance and Durability

Author(s): Alireza Haji Hossein, Hessam AzariJafari, and Rahil Khoshnazar

Publication: Symposium Paper

Volume: 361

Issue:

Appears on pages(s): 1-15

Keywords: Solid waste concrete, Life cycle assessment (LCA), Recycled concrete aggregate (RCA), Municipal solid waste incineration (MSWI), Scrap tire rubber (STR), Polyethylene terephthalate (PET)

DOI: 10.14359/51740603

Date: 3/1/2024

Abstract:
Portland cement concrete has shown great potential for recycling different waste materials. Solid waste incorporated concrete (SWC) is considered to have positive environmental advantages. However, the utilization of solid wastes may negatively impact the mechanical performance and durability of concrete. Therefore, any change in the performance metrics of SWC should be accounted for in the comparative life cycle assessment (LCA). This article will review the functional equivalency with respect to the mechanical performance and durability metrics for SWC incorporating four main streams of solid wastes; recycled concrete aggregate, municipal solid waste incineration ashes, scrap tire rubber, and polyethylene terephthalate. It will be shown that while in most cases, SWC may have an inferior compressive strength and/or durability pre-treatment, sorting, and appropriate replacement rate of the solid wastes may solve the problem and make SWC functionally equal to the conventional concrete. Moreover, some types of SWC such as those incorporating scrap tire rubber and polyethylene terephthalate may be more advantageous if used in specific applications where dynamic loads are prevalent given their superior impact resistance. Finally, the article will discuss new insights into defining the functional unit based on the performance and application of SWC to conduct a reliable LCA.