A proposal for the maximum use of recycled concrete sand in masonry mortar design

• Main Authors: E. Fernández-Ledesma, J. R. Jiménez, J. Ayuso, V. Corinaldesi, F. J. Iglesias-Godino
• Format: Article
• Language: English
• Published: Consejo Superior de Investigaciones Científicas 2016-03-01
• Series: Materiales de Construccion
• Subjects: mortar; compressive strength; mechanical properties; retraction; waste treatment
• Online Access: http://materconstrucc.revistas.csic.es/index.php/materconstrucc/article/view/1976

Natural sand mining from rivers and seashores is causing serious environmental problems in many parts of the world, whereas the fine fraction from recycling concrete waste is underutilized as a construction material. The aim of this paper is to determine the maximum replacement level of natural sand by recycled sand in the manufacturing of masonry mortar (M-10). For this purpose, five replacement levels were tested: 0%, 25%, 50%, 75% and 100% by volume. The mixes were made using cement CEM II/BL 32.5 N in a volumetric proportion of cement-to-aggregate of 1:5. A commercial admixture was used at a constant content. The amount of water was variable to achieve a consistency of 175±10 mm. The short- and long-term mortar properties were evaluated. The data were analyzed using a one-way ANOVA. In conclusion, a maximum percentage of 50% recycled concrete sand can be used in an indoor environment.