Optimisation of hybrid eco-efficient mortars with aggregates from construction and demolition waste and olive biomass ash

• Published in: Construction & building materials 2023-10, Vol.400, p.132634, Article 132634
• Main Authors: Rosales, M., Agrela, F., Sánchez de Rojas, M.I., Cabrera, M., Rosales, J.
• Format: Article
• Language: English
• Subjects: Cement mortars; Construction and demolition waste; Mixed recycled aggregates; Olive biomass bottom ash
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2023.132634

[Display omitted] •Improved mechanical performance of mortar mixes with BBA without fine particles.•Use of BBA and RMA significantly increases long-term mechanical strength.•Control of water/cement ratio and admixture to achieve mixes with improved mechanical properties. Materials considered as waste, such as Construction and Demolition Wastes (C&DW) and Biomass Bottom Ash (BBA) are the subject of this study to implement them in cement-based materials. After basic and advanced characterization, as well as leaching studies to assess the environmental impact, they are implemented in mortars as a replacement for standard silica sand. In this way, their mechanical behaviour, durability and micro-properties in hardened state are tested. The feasibility of implementing Mixed Recycled Aggregates (MRA) from C&DW and BBA to replace natural sand in high substitution rates is studied by substituting the wastes alone and in combination. Mortar mixes in which 50% of the aggregate is replaced, reaching more than 80% of the standard mortar strength. Mixtures in which 10% of the aggregate is replaced reaching more than 95% of the standard mortar strength.