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This paper analyses the influence of the fine fraction of two types of construction and 5 demolition waste (CDW1 and CDW2) on the properties of recycled aggregates (RA) and 6 masonry mortars. The CDW1's main component was ceramic while the CDW2 were 7 concrete. Three different kinds of fine RA were produced from each source of CDW; the 8 first type was produced by only using the fraction finer than 4.76 mm, the second one by 9 employing only the coarser fraction than 4.76 mm, and the third type was a mix of both 10 fractions of CDW. The masonry mortars were produced employing the 100% substitution 11 of natural aggregates. The results show that all the recycled mortars achieved a higher 12 water retentivity capacity than that of the conventional mortars. However, the sole use of 13 the fine fraction of the CDW was found to have a deleterious effect over the hardened 14 mortar properties, thus making it only adequate for the rendering or bonding of interior 15 walls at or above ground level. In contrast a combination of both the fine fraction and 16 coarse fraction of the CDW in the production of the RA achieved all the minimum 17 requirements for rendering and bonding masonry mortar. 18 Highlights 20  Two sources of CDW, one with ceramic and other with concrete as main components, 21 were employed. 22  Three different RA were obtained from two different sources of CDW. 23  Masonry mortars employing 100% of recycled aggregate were validated. 24  Ceramic high content recycled aggregates mortars achieved the most adequate 25 properties. 26  The employment of the coarse fraction of the CDW guarantee high quality aggregates 27 for masonry mortar. 28

This paper details the research work carried out on masonry mortars produced employing recycled aggregates in 100% substitution for natural sand aggregates. The main objective of the work being the validation of the resulting recycled aggregate mortar for use as a new construction material in Cuba. The recycled aggregates were acquired from the crushing of demolition material obtained from four different houses of distinct construction types. The work was carried out in two experimental stages. In stage 1, mortars with different percentages of recycled aggregates were produced and analysed. The analysis was carried out in order to achieve the optimal mix dosage, while employing the largest usable volume of recycled aggregates and in compliance with the functional requirements established by Cuban regulations. In stage 2, all mortars were produced employing the defined optimal mix proportion The fresh state properties (water retentivity) and hardened state (flexural, compression and bond strengths and capillary absorption capacity) were evaluated in the mortars produced with the other three mixed recycled aggregates of different compositions. It was concluded that the mortars produced with recycled aggregates needed less filler than that of the control mortar in order to obtain adequate properties in their fresh state. However, these recycled aggregate mortars obtained lower mechanical properties and higher capillary absorption that those of the control mortar. Nevertheless they were in compliance with the minimum requirements established in the Cuban regulation.Keywords: construction and demolition waste, recycled fine aggregate, masonry mortars, properties in fresh and hardened state Resumen En el presente trabajo se detalla la investigación llevada a cabo sobre morteros de albañilería utilizando áridos reciclados en sustitución al 100% de la arena natural. El objetivo principal del trabajo es la validación del mortero fabricado con árido reciclado como nuevo material de construcción en Cuba. Los áridos reciclados fueron obtenidos de la trituración del material de demolición de cuatro tipos de viviendas de diferente tipología de construcción. El trabajo se llevó a cabo en dos etapas experimentales. En la etapa 1, se fabricaron y analizaron morteros fabricados con diferentes porcentajes de un tipo de árido reciclado. El análisis se llevó a cabo con el fin de obtener la dosificación óptima del mortero utilizando el mayor porcentaje de árido reciclado posible y en cumplimiento con los requerimientos establecidos por las normas cubanas. En la etapa 2, todos los morteros se fabricaron utilizando la óptima dosificación definida en la etapa anterior. En cada mortero fabricado con los otros tres tipos de áridos reciclados obtenidos, se determinó la retención de agua en estado fresco, y las propiedades de resistencia a flexión, compresión y adherencia así como la absorción capilar en estado endurecido. Se concluyó que los morteros producidos con árido reciclados necesitan menos filler que el de mortero de contro...

RESUMENLos estudios de viabilidad realizados recientemente en La Habana, Cuba, muestran elevadas cifras de producción de residuos de construcción y demolición (RCD). Los últi-mos datos conocidos de generación de escombros de hormigón alcanzan valores cercanos a los 1.800 m 3 /mensual. Esta situación unida al agotamiento de los áridos en las zonas cercanas a la capital hace necesaria la utilización de estos escombros como áridos en la fabricación de hormigones. En el trabajo realizado se trituraron escombros de hormigón de cuatro orígenes diferentes, después de su caracterización se fabricaron hormigones con 25%, 50% y 100% de árido reciclado y con relaciones agua-cemento de 0,45, 0,50 y 0,55. A partir de la evaluación de las propiedades físico-mecánicas y de durabilidad obtenidas por los hormigones reciclados, se define la aplicabilidad de los mismos como hormigón estructural para ser utilizados en los diferentes tipos de ambientes de agresividad que tiene definido la normativa cubana.Palabras clave: residuos, reciclado, áridos, hormigón. SUMMARYThe recent viability studies carried out in Havana, Cuba, according to natural or recycled aggregates, exhibited high volume production of construction and demolition waste (CDW). The last well-known data of concrete waste generation reached to 1800 m 3 /month. This situation, together with the depletion of the quarry aggregates closed to the capital, requires the use of such debris as aggregate for concrete production. In this work, four origin recycled concrete aggregates (RCA) were produced and characterized. Recycled aggregate concrete with 25%, 50% and 100% of RCA and 0.45, 0.50 and 0.55 of water-cement ratio were produced. Physical, mechanical and durabilidty properties of thoses concretes were determined and evaluated, and their applicability as structural material in different aggressive environments according to Cuban normative was defined.