Investigation on the use of PET and XLPE plastic wastes as aggregates in cement-based mortars

Abstract

End-of-life plastics are an increasing environmental problem that needs to be addressed. Within the scope of utilizing secondary and recycled materials as aggregate in the construction industry, recycled XLPE and PET plastics were used as aggregates in cement-based mortars. The recycled plastics were reduced to fine aggregate granulometry and were used to partially replace natural sand in mortars. The replacement rates tested were 20% and 30% for XLPE, 30%, 50%, and 80% for PET, while a test mortar with 90% combined replacement with XLPE and PET was also tested. The workability of the mortars reduced with XLPE use and increased with PET use and the same pattern was observed regarding the porosity and water absorption of the hardened mortars. Compressive strength and density, on the other hand, reduced for both alternative aggregates, but recycled PET showed better performance overall and could be considered as an alternative for the production of lightweight mortars.