Lightweight masonry mortars made with expanded clay and recycled aggregates

• Aggregate from concrete waste and rubble are used to fabricate sustainable lightweight mortars.
• Materials are evaluated by means of physical, chemical and mechanical properties.
• Recycled materials show potential to be used.
• The economic study demonstrates the viability of this alternative.

One of the most extensive applications of recycled construction and demolition waste is as recycled aggregate in substitution of natural aggregate. An application for the fine fraction is investigated in this study by preparing lightweight mortars with different types of fine recycled aggregate from concrete waste and rubble. The properties of the materials are evaluated by means of physical and chemical characterization, their mechanical properties are tested, and the economic viability of the final product evaluated. In conclusion, despite the significant differences noted between the lightweight mortars and those incorporating natural aggregates, the former remain a technically and economically viable alternative.