Comparison of short and long-term performances of lightweight aggregate mortars made with polyurethane foam waste and expanded polystyrene beads

This article is part of a study on the valorization of rigid polyurethane foam (PUR) waste for the development of lightweight cementitious materials. Mortars were made with volume replacement rates of sand with plastic lightweight aggregates equal to 25 and 50%. To compare the benefits of the use of PUR foam in comparison with commercial lightweight aggregates, two types of aggregates were considered: PUR foam particles and expanded polystyrene beads. The workability, early-age hydration rate, mechanical properties (compressive strength and dynamic Young's modulus), thermophysical properties (thermal conductivity and specific heat), drying shrinkage and gas permeability were measured on the different mortars investigated. A comparative analysis of these properties was then proposed, which showed that it was possible to produce lightweight aggregate mortars for structural use using PUR foam waste and that PUR foam particles had a high potential for reducing the thermal conductivity mortars.